Abdomen: The belly, that part of the body that contains all of the structures between the chest and the pelvis. The abdomen is separated anatomically from the chest by the diaphragm, the powerful muscle spanning the body cavity below the lungs. See the entire definition of Abdomen
Abdominal: Relating to the abdomen, the belly, that part of the body that contains all of the structures between the chest and the pelvis. The abdomen is separated anatomically from the chest by the diaphragm, the powerful muscle spanning the body cavity below the lungs. See the entire definition of Abdominal
Abdominal pain: Pain in the belly (the abdomen). Abdominal pain can come from conditions affecting a variety of organs. The abdomen is an anatomical area that is bounded by the lower margin of the ribs above, the pelvic bone (pubic ramus) below, and the flanks on each side. Although abdominal pain can arise from the tissues of the abdominal wall that surround the abdominal cavity (the skin and abdominal wall muscles), the term abdominal pain generally is used to describe pain originating from organs within the abdominal cavity (from beneath the skin and muscles). These organs include the stomach, small intestine, colon, liver, gallbladder, and pancreas. See the entire definition of Abdominal pain
Abnormal: Not normal. Deviating from the usual structure, position, condition, or behavior. In referring to a growth, abnormal may mean that it is cancerous or premalignant (likely to become cancer).
Absorb:1. To take something in, as through the skin or the intestine. 2. To react with radiation and reduce it in intensity, as with a dose of radiation or transmitted light. See also: Absorbed dose; Absorption; Malabsorption; Reabsorption.
Absorption: Uptake. In the biomedical sciences, absorption has diverse specific meanings. See the entire definition of Absorption
Acidosis: Too much acid in the body, a distinctly abnormal condition resulting from the accumulation of acid or from the depletion of alkaline reserves. In acidosis, the pH of the blood is abnormally low. Acidosis is associated with diabetic ketoacidosis, lung disease, and severe kidney disease. The opposite of acidosis is alkalosis in which there is too high a pH due to excess base or insufficient acid in the body.
Adhesion: The union of two opposing tissue surfaces (often in reference to the sides of a wound). Also refers to scar tissue strands that can form in the area of a previous operation, such as within the abdomen after a laparotomy. See the entire definition of Adhesion
Alanine: An amino acid, one of the 20 building blocks of protein. Alanine is not an "essential" amino acid. It is not essential to the diet, but can be made by the body from other substances. Alanine was discovered in protein in 1875. Symbol: Ala.
Albumin: The main protein in human blood and the key to the regulation of the osmotic pressure of blood. Chemically, albumin is soluble in water, precipitated by acid, and coagulated by heat. See the entire definition of Albumin
Alkaline phosphatase: An enzyme made in the liver, bone, and the placenta and normally present in high concentrations in growing bone and in bile. Alkaline phosphatase is released into the blood during injury and during such normal activities as bone growth and pregnancy. It is measured in a routine blood test. See the entire definition of Alkaline phosphatase
Alveoli: The plural of alveolus. The alveoli are tiny air sacs within the lungs where the exchange of oxygen and carbon dioxide takes place.
Aminotransferase: An enzyme that catalyzes the transfer of an amino group from a donor molecule to a recipient molecule. The donor molecule is usually an amino acid while the recipient (acceptor) molecule is usually an alpha-2 keto acid. An aminotransferase is also called a transaminase. Two of the better known enzymes in this class are serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT). Both of these transaminases (SGOT and SGPT) are normally found primarily in cells in the liver and heart, are released into the bloodstream as the result of liver or heart damage, and so are used as liver and heart tests.
Ammonia: A colorless gas with a very sharp odor. Made both by humans and by nature, ammonia dissolves easily in water and evaporates quickly. Liquid ammonia is found in many household cleaners. Ammonia is irritating to the skin, eyes, nose, throat, and lungs. Exposure to high concentrations in the air can severely burn the skin, eyes, throat, or lungs. In extreme cases, blindness, lung damage, or death can occur. Breathing lower concentrations causes coughing and nose and throat irritation. Swallowing ammonia may burn the mouth, throat, and stomach. See the entire definition of Ammonia
Analysis: A psychology term for processes used to gain understanding of complex emotional or behavioral issues.
Anemia: The condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased. See the entire definition of Anemia
Ankle: The ankle joint is complex. It is made up of two joints: the true ankle joint and the subtalar joint: See the entire definition of Ankle
Antibody: An immunoglobulin, a specialized immune protein, produced because of the introduction of an antigen into the body, and which possesses the remarkable ability to combine with the very antigen that triggered its production. See the entire definition of Antibody
Antigen: A substance that is capable of causing the production of an antibody. See the entire definition of Antigen
Ascites: Abnormal buildup of fluid in the abdomen. Ascites can occur as a result of a number of conditions, including severe liver disease and the presence of malignant cells within the abdomen.
Asymptomatic: Without symptoms. For example, an asymptomatic infection is an infection with no symptoms.
Atypical: Not typical, not usual, not normal, abnormal. Atypical is often used to refer to the appearance of precancerous or cancerous cells.
Autoantibody: An antibody directed against the patient's own body tissue.
Autoimmune: Pertaining to autoimmunity, a misdirected immune response that occurs when the immune system goes awry and attacks the body itself. See the entire definition of Autoimmune
Autoimmune disease: An illness that occurs when the body tissues are attacked by its own immune system. The immune system is a complex organization within the body that is designed normally to "seek and destroy" invaders of the body, including infectious agents. Patients with autoimmune diseases frequently have unusual antibodies circulating in their blood that target their own body tissues. See the entire definition of Autoimmune disease
Autoimmune hepatitis: A disease in which the body's immune system attacks liver cells, causing inflammation of the liver (hepatitis). If not treated, autoimmune hepatitis can lead to cirrhosis (scarring and hardening) of the liver and eventually to liver failure.
Autoimmunity: A misdirected immune response that occurs when the immune system goes awry and attacks the body itself. See the entire definition of Autoimmunity
Bacteria: Single-celled microorganisms which can exist either as independent (free-living) organisms or as parasites (dependent upon another organism for life). See the entire definition of Bacteria
Bacterial: Of or pertaining to bacteria. For example, a bacterial lung infection.
Bile: Bile is a yellow-green fluid that is made by the liver, stored in the gallbladder and passes through the common bile duct into the duodenum where it helps digest fat. The principal components of bile are cholesterol, bile salts, and the pigment bilirubin. See the entire definition of Bile
Bile acid: An acid made by the liver that works with bile to break down fats. See the entire definition of Bile acid
Biliary: Having to do with the gallbladder, bile ducts, or bile. The biliary system itself consists of the gallbladder and bile ducts and, of course, the bile. See the entire definition of Biliary
Bilirubin: A yellow-orange compound produced by the breakdown of hemoglobin from red blood cells.
Biopsy: The removal of a sample of tissue for purposes of diagnosis. (Many definitions of "biopsy" stipulate that the sample of tissue is removed for examination under a microscope. This may or may not be the case. The diagnosis may be achieved by other means such as by analysis of chromosomes or genes.) See the entire definition of Biopsy
Booster shot: An additional dose of a vaccine needed periodically to "boost" the immune system. For example, a booster shot of the tetanus and diphtheria (Td) vaccine is recommended for adults every 10 years.
Bowel: Another name for the intestine. The small bowel and the large bowel are the small intestine and large intestine, respectively. See the entire definition of Bowel
Brain: That part of the central nervous system that is located within the cranium (skull). The brain functions as the primary receiver, organizer and distributor of information for the body. It has two (right and left) halves called "hemispheres."
Breast cancer:Breast cancer is diagnosed with self- and physician-examination of the breasts, mammography, ultrasound testing, and biopsy. There are many types of breast cancer that differ in their capability of spreading to other body tissues (metastasis). Treatment of breast cancer depends on the type and location of the breast cancer, as well as the age and health of the patient. The American Cancer Society recommends that a woman should have a baseline mammogram between the ages of 35 and 40 years. Between 40 and 50 years of age mammograms are recommended every other year. After age 50 years, yearly mammograms are recommended.
Breathing: The process of respiration, during which air is inhaled into the lungs through the mouth or nose due to muscle contraction, and then exhaled due to muscle relaxation.
Bypass: An operation in which a surgeon creates a new tubular pathway for the movement of fluids and/or other substances in the body.
Calcification: The process of building bone by suffusing tissues with calcium salts. Also called ossification.
Calcium: A mineral found mainly in the hard part of bones, where it is stored. Calcium is added to bones by cells called osteoblasts and is removed from bones by cells called osteoclasts. Calcium is essential for healthy bones. It is also important for muscle contraction, heart action, nervous system maintenance, and normal blood clotting. Food sources of calcium include dairy foods, some leafy green vegetables such as broccoli and collards, canned salmon, clams, oysters, calcium-fortified foods, and tofu. According to the National Academy of Sciences, adequate intake of calcium is 1,200 milligrams a day (four glasses of milk) for men and women 51 and older, 1,000 milligrams a day for adults 19 through 50, and 1,300 milligrams a day for children 9 through 18. The upper limit for calcium intake is 2.5 grams daily.
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Cancer: An abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread). See the entire definition of Cancer
Carcinoma:Cancer that begins in the skin or in tissues that line or cover body organs. For example, carcinoma can arise in the breast, colon, liver, lung, prostate, and stomach.
Cell: The basic structural and functional unit in people and all living things. Each cell is a small container of chemicals and water wrapped in a membrane. See the entire definition of Cell
Chest: The area of the body located between the neck and the abdomen. The chest contains the lungs, the heart and part of the aorta. The walls of the chest are supported by the dorsal vertebrae, the ribs, and the sternum. See the entire definition of Chest
Cholesterol: The most common type of steroid in the body, cholesterol has gotten something of a bad name. However, cholesterol is a critically important molecule. See the entire definition of Cholesterol
Chromosome: A visible carrier of the genetic information. See the entire definition of Chromosome
Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time. See the entire definition of Chronic
Circadian: Refers to events occurring within a 24-hour period, in the span of a full (24-hour) day, as in a circadian rhythm. Circadian rhythmicity is a fundamental property possessed by all organisms. These rhythms are driven by an internal time-keeping system: a clock. Changes in the external environment, particularly in the light-dark cycle, entrain this biologic clock. Under constant environmental conditions devoid of time cues, rhythms driven by the clock show a period near, but usually not exactly equal to, 24 hours. See the entire definition of Circadian
Cirrhosis: An abnormal liver condition characterized by irreversible scarring of the liver. Alcohol and viral hepatitis B and C are among the many causes of cirrhosis. Cirrhosis can cause yellowing of the skin (jaundice), itching, and fatigue. Diagnosis of cirrhosis can be suggested by physical examination and blood tests, and can be confirmed by liver biopsy in some patients. Complications of cirrhosis include mental confusion, coma, fluid accumulation (ascites), internal bleeding, and kidney failure. Treatment of cirrhosis is designed to limit any further damage to the liver as well as complications. Liver transplantation is becoming an important option for patients with advanced cirrhosis.
Colitis: Inflammation of the large intestine (the colon). There are many forms of colitis, including ulcerative colitis, Crohn's disease, infectious, pseudomembranous, and spastic. For example, intermittent rectal bleeding, crampy abdominal pain and diarrhea can be symptoms of ulcerative colitis. Diagnosis can be made by barium enema, but direct visualization (sigmoidoscopy or colonoscopy) is the most accurate test. Long-standing ulcerative colitis increases the risk for colon cancer. Ulcerative colitis can also be associated with inflammation in joints, spine, skin, eyes, the liver and its bile ducts. Treatment of ulcerative colitis can involve medications and surgery.
Coma: A state of deep unarousable unconsciousness. See the entire definition of Coma
Common bile duct: The duct that carries bile from the gallbladder and liver into the duodenum (the upper part of the small intestine). The common bile duct is formed by the junction of the cystic duct that comes from the gallbladder and the common hepatic duct that comes from the liver.
Contrast: Short for "contrast media." Contrast media are X-ray dyes used to provide contrast, for example, between blood vessels and other tissue.
CREST syndrome: A limited form of scleroderma, a disease of connective tissue with the formation of scar tissue (fibrosis) in the skin and sometimes also in other organs of the body. See the entire definition of CREST syndrome
Crohn's disease: A chronic inflammatory disease, primarily involving the small and large intestine, but which can affect other parts of the digestive system as well. It is named for Burrill Crohn, the American gastroenterologist who first described the disease in 1932. See the entire definition of Crohn's disease
CT scan: Computerized tomography scan. Pictures of structures within the body created by a computer that takes the data from multiple X-ray images and turns them into pictures on a screen. CT stands for computerized tomography. See the entire definition of CT scan
Cytotoxic: Toxic to cells, cell-toxic, cell-killing. Any agent or process that kills cells. Chemotherapy and radiotherapy are forms of cytotoxic therapy. They kill cells. See the entire definition of Cytotoxic
Depression: An illness that involves the body, mood, and thoughts, that affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. A depressive disorder is not the same as a passing blue mood. It is not a sign of personal weakness or a condition that can be wished away. People with a depressive disease cannot merely "pull themselves together" and get better. Without treatment, symptoms can last for weeks, months, or years. Appropriate treatment, however, can help most people with depression. See the entire definition of Depression
Detoxify: To reduce or eliminate the toxicity of a substance or poison. To promote the recovery of a person from an addictive drug such as alcohol or heroin.
Diabetes: Refers to diabetes mellitus or, less often, to diabetes insipidus. Diabetes mellitus and diabetes insipidus share the name "diabetes" because they are both conditions characterized by excessive urination (polyuria). See the entire definition of Diabetes
Diagnosis:1 The nature of a disease; the identification of an illness. 2 A conclusion or decision reached by diagnosis. The diagnosis is rabies. 3 The identification of any problem. The diagnosis was a plugged IV. See the entire definition of Diagnosis
Diarrhea: A familiar phenomenon with unusually frequent or unusually liquid bowel movements, excessive watery evacuations of fecal material. The opposite of constipation. The word "diarrhea" with its odd spelling is a near steal from the Greek "diarrhoia" meaning "a flowing through." Plato and Aristotle may have had diarrhoia while today we have diarrhea. There are myriad infectious and noninfectious causes of diarrhea. See the entire definition of Diarrhea
Dilate: To stretch or enlarge. It comes from the Latin verb "dilatare" meaning "to enlarge or expand."
Dilation: The process of enlargement, stretching, or expansion. The word "dilatation" means the same thing. Both come from the Latin "dilatare" meaning "to enlarge or expand."
Dry mouth: The condition of not having enough saliva to keep the mouth wet. This is due to inadequate function of the salivary glands. Everyone has dry mouth once in a while when they are nervous, upset or under stress. But if someone has a dry mouth most all of the time, it can be uncomfortable and lead to serious health problems. See the entire definition of Dry mouth
Duct: A passage or a tube with well-defined walls suitable for the conveyance of air or liquids, as the bile duct and the pancreatic duct. See the entire definition of Duct
Edema: The swelling of soft tissues as a result of excess water accumulation. See the entire definition of Edema
Encephalopathy: Disease, damage, or malfunction of the brain. In general, encephalopathy is manifested by an altered mental state that is sometimes accompanied by physical changes. Although numerous causes of encephalopathy are known, the majority of cases arise from infection, liver damage, anoxia, or kidney failure. The term encephalopathy is very broad and, in most cases, is preceded by various terms that describe the reason, cause, or special conditions of the patient that leads to brain malfunction. For example, anoxic encephalopathy means brain damage due to lack of oxygen, and hepatic encephalopathy means brain malfunction due to liver disease. Depending upon the cause and severity of the condition, symptoms may range from mild alterations in mental status to severe and potentially fatal manifestations such as dementia, seizures, and coma.
Endorphin: One of the body's own painkillers, an opioid (morphine-like) chemical produced by the body that serves to suppress pain. See the entire definition of Endorphin
Endoscope: A lighted optical instrument used to get a deep look inside the body and examine organs such as the throat or esophagus. An endoscope can be rigid or flexible. See the entire definition of Endoscope
Endoscopy: Endoscopy is a broad term used to described examining the inside of the body using a lighted, flexible instrument called an endoscope. In general, an endoscope is introduced into the body through a natural opening like the mouth or anus. Although endoscopy can include examination of other organs, the most common endoscopic procedures evaluate the esophagus (swallowing tube), stomach, and portions of the intestine.
Enlarged liver: A liver that is greater in size than normal. Enlarged liver is also known as hepatomegaly. Enlargement of the liver can occur in a wide variety of diseases. Examples include congestive heart failure, congenital diseases of metabolism, infections, tumors, and alcohol use.
Enzyme: A protein (or protein-based molecule) that speeds up a chemical reaction in a living organism. An enzyme acts as catalyst for specific chemical reactions, converting a specific set of reactants (called substrates) into specific products. Without enzymes, life as we know it would not exist. See the entire definition of Enzyme
Enzymes: Proteins that act as a catalysts in mediating and speeding a specific chemical reaction. See the entire definition of Enzymes
Epithelial: Relating to the epithelium, the outside layer of cells that covers all the free, open surfaces of the body including the skin, and mucous membranes that communicate with the outside of the body.
Esophagus: The tube that connects the pharynx (throat) with the stomach. The esophagus lies between the trachea (windpipe) and the spine. It passes down the neck, pierces the diaphragm just to the left of the midline, and joins the cardiac (upper) end of the stomach. In an adult, the esophagus is about 25 centimeters (10 inches) long. When a person swallows, the muscular walls of the esophagus contract to push food down into the stomach. Glands in the lining of the esophagus produce mucus, which keeps the passageway moist and facilitates swallowing. Also known as the gullet or swallowing tube. From the Greek oisophagos, from oisein meaning to bear or carry + phagein, to eat.
Essential:1. Something that cannot be done without. 2. Required in the diet, because the body cannot make it. As in an essential amino acid or an essential fatty acid. 3. Idiopathic. As in essential hypertension. "Essential" is a hallowed term meaning "We don't know the cause."
Estrogens: Female hormones produced by the ovaries. Estrogen deficiency can lead to osteoporosis. See the entire definition of Estrogens
Etiology: The study of the causes. For example, of a disorder. See the entire definition of Etiology
Evolution: The continuing process of change, especially in reference to natural selection. See the entire definition of Evolution
Fatigue: A condition characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness and tiredness. Fatigue can be acute and come on suddenly or chronic and persist. See the entire definition of Fatigue
Fats: Plural of the word "fat". See the definition of fat.
Fetus: The unborn offspring from the end of the 8th week after conception (when the major structures have formed) until birth. Up until the eighth week, the developing offspring is called an embryo.
Fever: Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.). See the entire definition of Fever
Fungus: A single-celled or multicellular organism. Fungi can be true pathogens (such as histoplasmosis and coccidioidomycosis) that cause infections in healthy persons or they can be opportunistic pathogens (such as aspergillosis, candidiasis, and cryptococcosis) that cause infections in immunocompromised persons (including cancer patients, transplant recipients, and persons with AIDS). An example of a common fungus is the yeast organism which causes thrush and diaper rash (diaper dermatitis). Fungi are also used for the development of antibiotics, antitoxins, and other drugs used to control various human diseases.
Gallbladder: A pear-shaped organ just below the liver that stores the bile secreted by the liver. During a fatty meal, the gallbladder contracts, delivering the bile through the bile ducts into the intestines to help with digestion. Abnormal composition of bile leads to formation of gallstones, a process termed cholelithiasis. The gallstones cause cholecystitis, inflammation of the gallbladder.
Gallstones: Stones that form when substances in the bile harden. Gallstones can be as small as a grain of sand or as large as a golf ball. There can be just one large stone, hundreds of tiny stones, or any combination. See the entire definition of Gallstones
Gastric: Having to do with the stomach.
Genes: The basic biological units of heredity. Segments of deoxyribonucleic acid (DNA) needed to contribute to a function. See the entire definition of Genes
Genetic: Having to do with genes and genetic information.
Genetics: The scientific study of heredity. Genetics pertains to humans and all other organisms. So, for example, there is human genetics, mouse genetics, fruitfly genetics, etc. See the entire definition of Genetics
Gland:1. A group of cells that secrete a substance for use in the body. For example, the thyroid gland. 2. A group of cells that removes materials from the circulation. For example, a lymph gland.
Gluten: A protein found in wheat or related grains and many foods that we eat. Gluten can be found in a large variety of foods including soups, salad dressings, processed foods and natural flavorings. Unidentified starch, binders and fillers in medications or vitamins can be unsuspected sources of gluten.
Heart: The muscle that pumps blood received from veins into arteries throughout the body. It is positioned in the chest behind the sternum (breastbone; in front of the trachea, esophagus, and aorta; and above the diaphragm muscle that separates the chest and abdominal cavities. The normal heart is about the size of a closed fist, and weighs about 10.5 ounces. It is cone-shaped, with the point of the cone pointing down to the left. Two-thirds of the heart lies in the left side of the chest with the balance in the right chest. See the entire definition of Heart
Heart muscle: A type of muscle with unique features only found in the heart. The heart muscle, or cardiac muscle, is medically called the myocardium ("myo-" being the prefix denoting muscle).
Heartburn: An uncomfortable feeling of burning and warmth occurring in waves rising up behind the breastbone (sternum) toward the neck. It is usually due to gastroesophageal reflux disease (GERD), the rise of stomach acid back up into the esophagus. Heartburn has nothing whatsoever to do with the heart. It is a popular nonmedical term. It is medically called pyrosis.
Hemoglobin: The oxygen-carrying pigment and predominant protein in the red blood cells. Hemoglobin forms an unstable, reversible bond with oxygen. In its oxygenated state it is called oxyhemoglobin and is bright red. In the reduced state it is called deoxyhemoglobin and is purple-blue. See the entire definition of Hemoglobin
Hepatic: Having to do with the liver. Pronounced hi-'pa-tik. From the Latin hepaticus derived from the Greek hepar meaning (not too surprisingly) the liver.
Hepatic encephalopathy: Brain dysfunction directly due to liver dysfunction, most often recognized in advanced liver disease. Hepatic encephalopathy may cause disturbances of consciousness and progress to coma. See the entire definition of Hepatic encephalopathy
Hepatocellular carcinoma: A tumor in which the cancer starts during adulthood in cells in the liver. Also called adult primary liver cancer. See the entire definition of Hepatocellular carcinoma
Heredity: Genetic transmission from parent to child.
HIV: Acronym for the Human Immunodeficiency Virus, the cause of AIDS (acquired immunodeficiency syndrome). HIV has also been called the human lymphotropic virus type III, the lymphadenopathy-associated virus and the lymphadenopathy virus. No matter what name is applied, it is a retrovirus. (A retrovirus has an RNA genome and a reverse transcriptase enzyme. Using the reverse transcriptase, the virus uses its RNA as a template for making complementary DNA which can integrate into the DNA of the host organism). See the entire definition of HIV
HLA: The major human histocompatibility system. HLA-typing is done before transplantation to determine the degree of histocompatibility. HLA is an acronym for Human Leukocyte Antigens.
Hoarseness:Hoarseness is a term referring to abnormal voice changes. Hoarseness may be manifested as a voice that sounds breathy, strained, rough, raspy, or a voice that has higher or lower pitch. There are many causes of hoarseness, including viral laryngitis, vocal cord nodules, laryngeal papillomas, gastroesophageal reflux-related laryngitis, and environmental irritants (such as tobacco smoking). An accumulation of fluid in the vocal cords associated with hoarseness has been termed Reinke's edema. Reinke's edema may occur as a result of cigarette smoking or voice abuse (prolonged or extended talking or shouting). Rarely, hoarseness results from serious conditions such as cancers of the head and neck region.
Hormone: A chemical substance produced in the body that controls and regulates the activity of certain cells or organs. See the entire definition of Hormone
Human immunodeficiency virus: HIV, the cause of AIDS. HIV has also been called the human lymphotropic virus type III, the lymphadenopathy-associated virus and the lymphadenopathy virus. No matter what name is applied, it is a retrovirus. (A retrovirus has an RNA genome and a reverse transcriptase enzyme. Using the reverse transcriptase, the virus uses its RNA as a template for making complementary DNA which can integrate into the DNA of the host organism). Although the American research Robert Gallo at the National Institutes of Health believed he was the first to find HIV, it is now generally accepted that the French physician Luc Montagnier (1932-) and his team at the Pasteur Institute discovered HIV in 1983- 84.
Hypercalcemia: A higher-than-normal level of calcium in the blood. This can cause a number of nonspecific symptoms, including loss of appetite, nausea, thirst, fatigue, muscle weakness, restlessness, and confusion. Excessive intake of calcium may cause muscle weakness and constipation, affect the conduction of electrical impulses in the heart (heart block) lead to calcium stones (nephrocalcinosis), in the urinary tract, impair kidney function, and interfere with the absorption of iron predisposing to iron deficiency. According to the National Academy of Sciences, adequate intake of calcium is 1 gram daily for both men and women. The upper limit for calcium intake is 2.5 grams daily.
Hyperpigmentation: Dark spots on the skin. Hyperpigmentation is primarily a cosmetic concern that can be covered with make-up, although in some cases (such as the cafe au lait spots associated with neurofibromatosis) it can be a sign of an underlying medical problem. If treatment of hyperpigmentation is desired, a dermatologist may be able to use dermabrasion, laser treatments, or bleaching agents to effect change.
Hypertension: High blood pressure, defined as a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140 with a diastolic pressure above 90. See the entire definition of Hypertension
Hypoglycemia: Low blood sugar (glucose). When symptoms of hypoglycemia occur together with a documented blood glucose under 45 mg/dl, and the symptoms promptly resolve with the administration of glucose, the diagnosis of hypoglycemia can be made with some certainty. Hypoglycemia is only significant when it is associated with symptoms. See the entire definition of Hypoglycemia
Hypothyroid: Deficiency of thyroid hormone which is normally made by the thyroid gland which is located in the front of the neck:
Immune: Protected against infection. The Latin immunis means free, exempt.
Immune response: Any reaction by the immune system.
Immune system: A complex system that is responsible for distinguishing us from everything foreign to us, and for protecting us against infections and foreign substances. The immune system works to seek and kill invaders. See the entire definition of Immune system
Immunity: The condition of being immune. Immunity can be innate (for example, humans are innately immune to canine distemper) or conferred by a previous infection or immunization.
Immunization: Vaccination. Immunizations work by stimulating the immune system, the natural disease-fighting system of the body. The healthy immune system is able to recognize invading bacteria and viruses and produce substances (antibodies) to destroy or disable them. Immunizations prepare the immune system to ward off a disease. To immunize against viral diseases, the virus used in the vaccine has been weakened or killed. To immunize against bacterial diseases, it is generally possible to use only a small portion of the dead bacteria to stimulate the formation of antibodies against the whole bacteria. In addition to the initial immunization process, it has been found that the effectiveness of immunizations can be improved by periodic repeat injections or "boosters." Also see Immunizations (in the plural) and Immunization of a specific type (such Immunization, Polio).
Immunodeficiency: Inability to mount a normal immune response. Immunodeficiency can be due to a genetic disease or acquired as in AIDS due to HIV.
Immunoglobulin: A protein produced by plasma cells and lymphocytes and characteristic of these types of cells. Immunoglobulins play an essential role in the body's immune system. They attach to foreign substances, such as bacteria, and assist in destroying them. Immunoglobulin is abbreviated Ig. The classes of immunoglobulins are termed immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM), immunoglobulin D (IgD) and immunoglobulin E (IgE).
Immunoglobulin M: Abbreviated IgM. A major class of immunoglobulins. IgM includes the antibodies that are usually produced first in an immune response and are later replaced by other types of antibodies.
Incidence: The frequency with which something, such as a disease, appears in a particular population or area. In disease epidemiology, the incidence is the number of newly diagnosed cases during a specific time period. The incidence is distinct from the prevalence which refers to the number of cases alive on a certain date.
Indicate: In medicine, to make a treatment or procedure advisable because of a particular condition or circumstance. For example, certain medications are indicated for the treatment of hypertension during pregnancy while others are contraindicated.
Indication:1. In medicine, a condition which makes a particular treatment or procedure advisable. CML (chronic myeloid leukemia) is an indication for the use of Gleevec (imatinib mesylate). 2. A sign or a circumstance which points to or shows the cause, pathology, treatment, or outcome of an attack of disease. The presence of the Philadelphia chromosome in peripheral blood cells is an indication of a relapse in CML.
Infection: The growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person. See the entire definition of Infection
Inflammation: A basic way in which the body reacts to infection, irritation or other injury, the key feature being redness, warmth, swelling and pain. Inflammation is now recognized as a type of nonspecific immune response. See the entire definition of Inflammation
Inflammatory bowel disease: A group of chronic intestinal diseases characterized by inflammation of the bowel -- the large or small intestine. The most common types of inflammatory bowel disease (IBD) are ulcerative colitis and Crohn disease. See the entire definition of Inflammatory bowel disease
Injury: Harm or hurt. The term "injury" may be applied in medicine to damage inflicted upon oneself as in a hamstring injury or by an external agent on as in a cold injury. The injury may be accidental or deliberate, as with a needlestick injury. The term "injury" may be synonymous (depending on the context) with a wound or with trauma.
Insulin: A natural hormone made by the pancreas that controls the level of the sugar glucose in the blood. Insulin permits cells to use glucose for energy. Cells cannot utilize glucose without insulin. See the entire definition of Insulin
Intercellular: Between cells, as in an intercellular bridge.
Interstitial: Pertaining to being between things, especially between things that are normally closely spaced. See the entire definition of Interstitial
Intestine: The long, tubelike organ in the abdomen that completes the process of digestion. It consists of the small and large intestines.
Itching: An uncomfortable sensation in the skin that feels as if something is crawling on the skin or in the skin, and makes the person want to scratch the affected area. See the entire definition of Itching
Jaundice: Yellow staining of the skin and sclerae (the whites of the eyes) by abnormally high blood levels of the bile pigment bilirubin. The yellowing extends to other tissues and body fluids. Jaundice was once called the "morbus regius" (the regal disease) in the belief that only the touch of a king could cure it. See the entire definition of Jaundice
Joint: A joint is the area where two bones are attached for the purpose of motion of body parts. A joint is usually formed of fibrous connective tissue and cartilage. An articulation or an arthrosis is the same as a joint. See the entire definition of Joint
Kidney: One of a pair of organs located in the right and left side of the abdomen which clear "poisons" from the blood, regulate acid concentration and maintain water balance in the body by excreting urine. The kidneys are part of the urinary tract. The urine then passes through connecting tubes called "ureters" into the bladder. The bladder stores the urine until it is released during urination.
Laboratory: A place for doing tests and research procedures and preparing chemicals, etc. Although "laboratory" looks very like the Latin "laboratorium" (a place to labor, a work place), the word "laboratory" came from the Latin "elaborare" (to work out, as a problem, and with great pains), as evidenced by the Old English spelling "elaboratory" designating "a place where learned effort was applied to the solution of scientific problems."
Large intestine: Comes after the small intestine. Large because it is wider than the small intestine.
Larynx: The larynx is the portion of the breathing, or respiratory, tract containing the vocal cords which produce vocal sound. It is located between the pharynx and the trachea. The larynx, also called the voice box, is a 2-inch-long, tube-shaped organ in the neck.
Leg: In popular usage, the leg extends from the top of the thigh down to the foot. However, in medical terminology, the leg refers to the portion of the lower extremity from the knee to the ankle. See the entire definition of Leg
Lipids: Another word for "fats." (Please see the various meanings of Fat.) Lipids can be more formally defined as substances such as a fat, oil or wax that dissolves in alcohol but not in water. Lipids contain carbon, hydrogen and oxygen but have far less oxygen proportionally than carbohydrates. See the entire definition of Lipids
Liver: An organ in the upper abdomen that aids in digestion and removes waste products and worn-out cells from the blood. The liver is the largest solid organ in the body. The liver weighs about three and a half pounds (1.6 kilograms). It measures about 8 inches (20 cm) horizontally (across) and 6.5 inches (17 cm) vertically (down) and is 4.5 inches (12 cm) thick.
Liver biopsy: A procedure in which a small sample of the liver is removed for the diagnosis of abnormal liver conditions. See the entire definition of Liver biopsy
Liver disease: Liver disease refers to any disorder of the liver. The liver is a large organ in the upper right abdomen that aids in digestion and removes waste products from the blood. See the entire definition of Liver disease
Liver transplant: Surgery to remove a diseased liver and replace it with a healthy liver (or part of one) from a donor. The most common reasons for liver transplantation in children is biliary atresia (a disease in which the ducts that carry bile out of the liver are missing or damaged) while in adults the most common reason for a liver transplant is cirrhosis (a disease in which healthy liver cells are killed and replaced with scar tissue). See the entire definition of Liver transplant
Low blood sugar: A low blood level of the sugar glucose. Also called hypoglycemia. See the entire definition of Low blood sugar
Lungs: The lungs are a pair of breathing organs located with the chest which remove carbon dioxide from and bring oxygen to the blood. There is a right and left lung.
Lymphocytes: A small white blood cell (leukocyte) that plays a large role in defending the body against disease. See the entire definition of Lymphocyte
Magnetic resonance imaging: A special radiology technique designed to image internal structures of the body using magnetism, radio waves, and a computer to produce the images of body structures. In magnetic resonance imaging (MRI), the scanner is a tube surrounded by a giant circular magnet. The patient is placed on a moveable bed that is inserted into the magnet. The magnet creates a strong magnetic field that aligns the protons of hydrogen atoms, which are then exposed to a beam of radio waves. This spins the various protons of the body, and they produce a faint signal that is detected by the receiver portion of the MRI scanner. A computer processes the receiver information, and an image is produced. The image and resolution is quite detailed and can detect tiny changes of structures within the body, particularly in the soft tissue, brain and spinal cord, abdomen and joints. See the entire definition of Magnetic resonance imaging
Malabsorption: The impaired absorption by the intestines of nutrients from food. Malabsorption can be specific and involve sugars, fats, proteins, or vitamins. Alternatively, malabsorption can be general and nonspecific. See the entire definition of Malabsorption
Malignancy: A tumor that is malignant, that is cancerous, that can invade and destroy nearby tissue, and that may spread (metastasize) to other parts of the body.
Marker: A piece of DNA that lies on a chromosome so close to a gene that the marker and the gene are inherited together. A marker is thus an identifiable heritable spot on a chromosome. A marker can be an expressed region of DNA (a gene) or a segment of DNA with no known coding function. All that matters is that the marker can be detected and trailed. See the entire definition of Marker
Median: The middle. Like the median strip in a highway.
Melanin: A skin pigment (substance that gives the skin its color). Dark-skinned people have more melanin than light- skinned people. Melanin also acts as a sunscreen and protects the skin from ultraviolet light. See the entire definition of Melanin
Memory:1. The ability to recover information about past events or knowledge. 2. The process of recovering information about past events or knowledge. 3. Cognitive reconstruction. The brain engages in a remarkable reshuffling process in an attempt to extract what is general and what is particular about each passing moment. See the entire definition of Memory
Menopause: The time in a woman's life when menstrual periods permanently stop; it is also called the "change of life." Menopause is the opposite of the menarche. See the entire definition of Menopause
Metabolic: Relating to metabolism, the whole range of biochemical processes that occur within us (or any living organism). Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances). See the entire definition of Metabolic
Metabolism: The whole range of biochemical processes that occur within an organism. Metabolism consists both of anabolism and catabolism (the buildup and breakdown of substances, respectively). The biochemical reactions are known as metabolic pathways and involve enzymes that transform one substance into another substance, either breaking down a substance or building a new chemical substance. The term is commonly used to refer specifically to the breakdown of food and its transformation into energy.
Metastasize: The spread from one part of the body to another. When cancer cells metastasize and cause secondary tumors, the cells in the metastatic tumor are like those in the original cancer.
Microscope: An optical instrument that augments the power of the eye to see small objects. The name microscope was coined by Johannes Faber (1574-1629) who in 1628 borrowed from the Greek to combined micro-, small with skopein, to view. Although the first microscopes were simple microscopes, most (if not all) optical microscopes today are compound microscopes.
Microscopic: So small it cannot be seen without the aid of microscope. As opposed to macroscopic (large enough to be seen with naked eye). A tiny tumor is microscopic while a big tumor is macroscopic.
Miscarriage: Inadvertent loss of a pregnancy before the fetus is viable. A considerable proportion of pregnancies end in a miscarriage. Also called a spontaneous abortion.
Mitochondria: Normal structures responsible for energy production in cells. Mitochondria are located in the cytoplasm outside the nucleus of the cell. They consist of two sets of membranes, a smooth continuous outer coat and an inner membrane arranged in tubules or in folds that form plate-like double membranes (cristae). See the entire definition of Mitochondria
Mitochondrial: Referring to mitochondria. The mitochondria are normal structures called organelles in cells. They are located in the cell's cytoplasm outside the nucleus. See the entire definition of Mitochondrial
Morphine: A powerful narcotic agent with strong analgesic (painkilling) action and other significant effects on the central nervous system. It is dangerously addicting. Morphine is a naturally occurring member of a large chemical class of compounds called alkaloids. See the entire definition of Morphine
Mouth:1. The upper opening of the digestive tract, beginning with the lips and containing the teeth, gums, and tongue. Foodstuffs are broken down mechanically in the mouth by chewing and saliva is added as a lubricant. Saliva contains amylase, an enzyme that digests starch. 2. Any opening or aperture in the body. The mouth in both senses of the word is also called the os, the Latin word for an opening, or mouth. The o in os is pronounced as in hope. The genitive form of os is oris from which comes the word oral.
Muscle: Muscle is the tissue of the body which primarily functions as a source of power. There are three types of muscle in the body. Muscle which is responsible for moving extremities and external areas of the body is called "skeletal muscle." Heart muscle is called "cardiac muscle." Muscle that is in the walls of arteries and bowel is called "smooth muscle."
Muscular: Having to do with the muscles. Also, endowed with above average muscle development. Muscular system refers to all of the muscles of the body collectively.
Nausea:Nausea, is the urge to vomit. It can be brought by many causes including, systemic illnesses, such as influenza, medications, pain, and inner ear disease. When nausea and/or vomiting are persistent, or when they are accompanied by other severe symptoms such as abdominal pain, jaundice, fever, or bleeding, a physician should be consulted.
Neck: The part of the body joining the head to the shoulders. Also, any narrow or constricted part of a bone or organ that joins its parts as, for example, the neck of the femur bone.
Nerve: A bundle of fibers that uses chemical and electrical signals to transmit sensory and motor information from one body part to another. See: Nervous system.
Neuropathy: Any and all disease or malfunction of the nerves.
Nutrition: 1) The science or practice of taking in and utilizing foods. 2) A nourishing substance, such as nutritional solutions delivered to hospitalized patients via an IV or IG tube.
Onset: In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of rheumatoid arthritis. There is always an onset to a disease but never to the return to good health. The default setting is good health. See the entire definition of Onset
Organ: A relatively independent part of the body that carries out one or more special functions. The organs of the human body include the eye, ear, heart, lungs, and liver.
Osteomalacia: Softening of bone, particularly in the sense of bone weakened by demineralization (the loss of mineral) and most notably by the depletion of calcium from bone. See the entire definition of Osteomalacia
Osteopenia: Mild thinning of the bone mass, but not as severe as osteoporosis. Osteopenia results when the formation of bone (osteoid synthesis) is not enough to offset normal bone loss (bone lysis). Osteopenia is generally considered the first step along the road to osteoporosis, a serious condition in which bone density is extremely low and bones are porous and prone to shatter. Diminished bone calcification, as seen on plain X-ray film, is referred to as osteopenia, whether or not osteoporosis is present. The diagnosis of osteopenia may also be made by a special X-ray machine for bone density testing. See the entire definition of Osteopenia
Osteoporosis: Thinning of the bones with reduction in bone mass due to depletion of calcium and bone protein. Osteoporosis predisposes a person to fractures, which are often slow to heal and heal poorly. It is more common in older adults, particularly post-menopausal women; in patients on steroids; and in those who take steroidal drugs. Unchecked osteoporosis can lead to changes in posture, physical abnormality (particularly the form of hunched back known colloquially as "dowager's hump"), and decreased mobility. See the entire definition of Osteoporosis
Oxygen: A colorless, odorless and tasteless gas that makes up about 20% of the air we breathe (and at least half the weight of the entire solid crust of the earth) and which combines with most of the other elements to form oxides. Oxygen is essential to human, animal and plant life. See the entire definition of Oxygen
Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors. See the entire definition of Pain
Pancreas: A fish-shaped spongy grayish-pink organ about 6 inches (15 cm) long that stretches across the back of the abdomen, behind the stomach. The head of the pancreas is on the right side of the abdomen and is connected to the duodenum (the first section of the small intestine). The narrow end of the pancreas, called the tail, extends to the left side of the body.
Pancreatic: Having to do with the pancreas, a spongy, tube-shaped organ about 6 inches long. It is located in the back of the abdomen, behind the stomach. The head of the pancreas is on the right side of the abdomen. It is connected to the duodenum, the upper end of the small intestine. The narrow end of the pancreas, called the tail, extends to the left side of the body.
Pancreatic insufficiency: Not enough of the digestive enzymes normally secreted by the pancreas into the intestine. Pancreatic insufficiency is a hallmark of cystic fibrosis.
Parasite: An organism that lives in or on and takes its nourishment from another organism. A parasite cannot live independently. See the entire definition of Parasite
Pathogenesis: The development of a disease. The origin of a disease and the chain of events leading to that disease.
Pathology: The study of disease. Pathology has been defined as "that branch of medicine which treats of the essential nature of disease." The word "pathology" comes from the Greek words "pathos" meaning "disease" and "logos" meaning "a treatise" = a treatise of disease. The word "pathology" is sometimes misused to mean disease as, for example, "he didn't find any pathology" (meaning he found no evidence of disease). A medical doctor that specializes in pathology is called a pathologist. Pathologists are experts at interpreting microscopic views of body tissues.
Pelvis: The lower part of the abdomen located between the hip bones.
Pigment: A substance that gives color to tissue. Pigments are responsible for the color of skin, eyes, and hair.
Pigmentation: The coloring of the skin, hair, mucous membranes, and retina of the eye. See the entire definition of Pigmentation
Pitting edema: Observable swelling of body tissues due to fluid accumulation that may be demonstrated by applying pressure to the swollen area (such as by depressing the skin with a finger). If the pressing causes an indentation that persists for some time after the release of the pressure, the edema is referred to as pitting edema. See the entire definition of Pitting edema
Platelet: An irregular, disc-shaped element in the blood that assists in blood clotting. During normal blood clotting, the platelets clump together (aggregate). Although platelets are often classed as blood cells, they are actually fragments of large bone marrow cells called megakaryocytes.
Platelet count: The calculated number of platelets in a volume of blood, usually expressed as platelets per cubic millimeter (cmm) of whole blood. Platelets are the smallest cell-like structures in the blood and are important for blood clotting and plugging damaged blood vessels. Platelet counts are usually done by laboratory machines that also count other blood elements such as the white and red cells. They can also be counted by use of a microscope. Normal platelet counts are in the range of 150,000 to 400,000 per microliter (or 150 - 400 x 109 per liter). These values many vary slightly between different laboratories.
Portal vein: A large vein that carries blood from the stomach and the intestines to the liver. See the entire definition of Portal vein
Pregnancy: The state of carrying a developing embryo or fetus within the female body. This condition can be indicated by positive results on an over-the-counter urine test, and confirmed through a blood test, ultrasound, detection of fetal heartbeat, or an X-ray. Pregnancy lasts for about nine months, measured from the date of the woman's last menstrual period (LMP). It is conventionally divided into three trimesters, each roughly three months long. See the entire definition of Pregnancy
Pregnant: The state of carrying a developing fetus within the body. See the entire definition of Pregnant
Prevalence: The proportion of individuals in a population having a disease. Prevalence is a statistical concept referring to the number of cases of a disease that are present in a particular population at a given time.
Prognosis:1. The expected course of a disease. 2. The patient's chance of recovery. The prognosis predicts the outcome of a disease and therefore the future for the patient. His prognosis is grim, for example, while hers is good. See the entire definition of Prognosis
Progressive: Increasing in scope or severity. Advancing. Going forward. In medicine, a disease that is progressive is going from bad to worse.
Protein: A large molecule composed of one or more chains of amino acids in a specific order determined by the base sequence of nucleotides in the DNA coding for the protein. See the entire definition of Protein
Proteins: Large molecules composed of one or more chains of amino acids in a specific order determined by the base sequence of nucleotides in the DNA coding for the protein. See the entire definition of Proteins
Prothrombin: A coagulation (clotting) factor that is needed for the normal clotting of blood. A cascade of biochemical events leads to the formation of the final clot. In this cascade, prothrombin is a precursor to thrombin. See the entire definition of Prothrombin
Prothrombin time: A clotting test, the prothrombin time is done to test the integrity of part of the clotting scheme. The prothrombin time is commonly used as a method of monitoring the accuracy of blood thinning treatment (anticoagulation) with warfarin (Coumadin). Familiarly called the "pro time," the test is the time needed for clot formation after a substance called thromboplastin (+ calcium) has been added to plasma. See the entire definition of Prothrombin time
Pruritus: Itching. Pruritus can result from drug reaction, food allergy, kidney or liver disease, cancers, parasites, aging or dry skin, contact skin reaction, such as poison ivy, and for unknown reasons.
Pulmonary: Having to do with the lungs. (The word comes from the Latin pulmo for lung).
Raynaud's phenomenon: A condition resulting in discoloration of fingers and/or toes when a person is exposed to changes in temperature (cold or hot) or emotional events. See the entire definition of Raynaud's phenomenon
Recurrence: The return of a sign, symptom or disease after a remission. The reappearance of cancer cells at the same site or in another location is, unfortunately, a familiar form of recurrence. See the entire definition of Recurrence
Recurrent: Back again. A recurrent fever is a fever that has returned after an intermission: a recrudescent fever.
Red blood cell: The blood cell that carries oxygen. Red cells contain hemoglobin and it is the hemoglobin which permits them to transport oxygen (and carbon dioxide). Hemoglobin, aside from being a transport molecule, is a pigment. It gives the cell its red color (and name). See the entire definition of Red blood cell
Red blood cells: The blood cells that carry oxygen. Red cells contain hemoglobin and it is the hemoglobin which permits them to transport oxygen (and carbon dioxide). Hemoglobin, aside from being a transport molecule, is a pigment. It gives the cells their red color (and their name). See the entire definition of Red blood cells
Reflux: The term used when liquid backs up into the esophagus from the stomach.
Renal: Having to do with the kidney. From the Latin renes (the kidneys), which gave the French les reins which mean both the kidneys and the lower back.
Resistance: Opposition to something, or the ability to withstand it. For example, some forms of staphylococcus are resistant to treatment with antibiotics.
Retrovirus: An RNA virus (a virus composed not of DNA but of RNA). Retroviruses have an enzyme called reverse transcriptase that gives them the unique property of transcribing RNA (their RNA) into DNA. The retroviral DNA can then integrate into the chromosomal DNA of the host cell to be expressed there. The human immunodeficiency virus (HIV), the cause of AIDS, is a retrovirus.
Rheumatic fever: An illness that occurs following a streptococcus infection (such as a "strep throat") or scarlet fever and predominantly affects children. Symptoms include fever, pain in the joints, nausea, stomach cramps, and vomiting. Rheumatic fever can cause long-lasting effects in the skin, joints, heart, and brain. See the entire definition of Rheumatic fever
Rheumatoid arthritis: An autoimmune disease which causes chronic inflammation of the joints, the tissue around the joints, as well as other organs in the body. Autoimmune diseases occur when the body tissues are mistakenly attacked by its own immune system. The immune system is a complex organization of cells and antibodies designed normally to "seek and destroy" invaders of the body, particularly infections. Patients with these diseases have antibodies in their blood which target their own body tissues, where they can be associated with inflammation. Because it can affect multiple other organs of the body, rheumatoid arthritis is referred to as a systemic illness and is sometimes called rheumatoid disease. While rheumatoid arthritis is a chronic illness (meaning it can last for years) patients may experience long periods without symptoms. See the entire definition of Rheumatoid arthritis
Rheumatoid factor:Rheumatoid factor is an abnormal antibody that is measurable in the blood. Rheumatoid factor is commonly used as a blood test for the diagnosis of rheumatoid arthritis. Rheumatoid factor is present in about 80% of adults (but a much lower proportion of children) with rheumatoid arthritis. It is also present in patients with other connective tissue diseases such as systemic lupus erythematosus and Sjögren's syndrome, and some with infections diseases including infectious hepatitis.
Risk factor: Something that increases a person's chances of developing a disease.
Saliva: a watery secretion in the mouth produced by the salivary glands that aids in the digestion of food. Saliva also serves to moisten and cleanse the mouth, including the tongue and teeth, and contains substances that can play a role in the prevention of infection. Saliva aids digestion by moistening food and contains enzymes that begin the digestion process. Also known as spit.
Scan: As a noun, the data or image obtained from the examination of organs or regions of the body by gathering information with a sensing device. See the entire definition of Scan
Sclerodactyly: Localized thickening and tightness of the skin of the fingers or toes. Sclerodactyly is commonly associated with atrophy of the underlying soft tissues. See the entire definition of Sclerodactyly
Scleroderma: A disease of connective tissue with the formation of scar tissue (fibrosis) in the skin and sometimes also in other organs of the body. See the entire definition of Scleroderma
Sensation: In medicine and physiology, sensation refers to the registration of an incoming (afferent) nerve impulse in that part of the brain called the sensorium, which is capable of such perception. Therefore, the awareness of a stimulus as a result of its perception by sensory receptors. (Sensory is here synonymous with sensation.) See the entire definition of Sensation
Serum: The clear liquid that can be separated from clotted blood. Serum differs from plasma, the liquid portion of normal unclotted blood containing the red and white cells and platelets. It is the clot that makes the difference between serum and plasma. See the entire definition of Serum
Sicca syndrome: An autoimmune disease, also known as Sjogren syndrome, that classically combines dry eyes, dry mouth, and another disease of connective tissue such as rheumatoid arthritis (most common), lupus, scleroderma or polymyositis. See the entire definition of Sicca syndrome
Small intestine: The part of the digestive tract that extends from the stomach to the large intestine.
Spinal cord: The major column of nerve tissue that is connected to the brain and lies within the vertebral canal and from which the spinal nerves emerge. Thirty-one pairs of spinal nerves originate in the spinal cord: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. The spinal cord and the brain constitute the central nervous system (CNS). The spinal cord consists of nerve fibers that transmit impulses to and from the brain. Like the brain, the spinal cord is covered by three connective-tissue envelopes called the meninges. The space between the outer and middle envelopes is filled with cerebrospinal fluid (CSF), a clear colorless fluid that cushions the spinal cord against jarring shock. Also known simply as the cord. See the entire definition of Spinal cord
Spine: 1) The column of bone known as the vertebral column, which surrounds and protects the spinal cord. The spine can be categorized according to level of the body: i.e., cervical spine (neck), thoracic spine (upper and middle back), and lumbar spine (lower back). See also vertebral column. 2) Any short prominence of bone. The spines of the vertebrae protrude at the base of the back of the neck and in the middle of the back. These spines protect the spinal cord from injury from behind.
Spleen: An organ located in the upper left part of the abdomen near the stomach. The spleen produces lymphocytes; it is the largest lymphatic organ in the body. The spleen also filters the blood, serves as a major reservoir for blood and destroys blood cells that are aged.
Stage: As regards cancer, the extent of a cancer, especially whether the disease has spread from the original site to other parts of the body. See also: Staging.
Staging: In regard to cancer, the process of doing examinations and tests to learn the extent of the cancer, especially whether it has metastasized (spread) from its original site to other parts of the body.
Stasis: Stasis refers to a stoppage or slowdown in the flow of blood (or other body fluid such as lymph). See the entire definition of Stasis
Stomach:1. The sac-shaped digestive organ that is located in the upper abdomen, under the ribs. The upper part of the stomach connects to the esophagus, and the lower part leads into the small intestine. See the entire definition of Stomach
Strep: Very commonly used shortened form of Streptococcus, a very common and important group of bacteria. See Streptococcus
Strep throat:Strep throat is an infection caused by a type of bacteria called streptococcus, which can lead to serious complications if not adequately treated.
Substance:1. Material with particular features, as a pressor substance. 2. The material that makes up an organ or structure. Also known in medicine as the substantia. 3. A psychoactive drug as, for example, in substance abuse.
Suicidal: Pertaining to suicide. the taking of ones own life. As in a suicidal gesture, suicidal thought, or suicidal act. An "online lifeline for suicidal undergrads" may help prevent college students from committing suicide.
Symptom: Any subjective evidence of disease. Anxiety, lower back pain, and fatigue are all symptoms. They are sensations only the patient can perceive. In contrast, a sign is objective evidence of disease. A bloody nose is a sign. It is evident to the patient, doctor, nurse and other observers.
Syndrome: A set of signs and symptoms that tend to occur together and which reflect the presence of a particular disease or an increased chance of developing a particular disease. See the entire definition of Syndrome
Tetanus: An often fatal infectious disease caused by the bacteria Clostridium tetani (C. tetani) which usually enters the body through a puncture, cut, or open wound. Tetanus is characterized by profoundly painful spasms of muscles, including "locking" of the jaw so that the mouth cannot open (lockjaw). C. tetani releases a toxin that affects the motor nerves, (the nerves which stimulate the muscles). See the entire definition of Tetanus
Therapeutic: Relating to therapeutics, that part of medicine concerned specifically with the treatment of disease. The therapeutic dose of a drug is the amount needed to treat a disease. See the entire definition of Therapeutic
Throat: The throat is the anterior (front) portion of the neck beginning at the back of the mouth, consisting anatomically of the pharynx and larynx. The throat contains the trachea and a portion of the esophagus.
Thrombocytopenia: A low platelet count. Platelets are irregular, disc-shaped element in the blood that assists in blood clotting. thrombocytopenia can arise due to decreased production of platelets in the bone marrow or increased breakdown of platelets in the bloodstream, spleen, or liver. Thrombocytopenia is characterized by easy bruising and increased bleeding.
Thyroid:1. The thyroid gland. Also, pertaining to the thyroid gland. 2. A preparation of the thyroid gland used to treat hypothyroidism. 3. Shaped like a shield. (The thyroid gland was so-named by Thomas Wharton in 1656 because it was shaped like an ancient Greek shield.) See the entire definition of Thyroid
Thyroid gland: A gland that makes and stores hormones that help regulate the heart rate, blood pressure, body temperature, and the rate at which food is converted into energy. Thyroid hormones are essential for the function of every cell in the body. They help regulate growth and the rate of chemical reactions (metabolism) in the body. Thyroid hormones also help children grow and develop. See the entire definition of Thyroid gland
Thyroid hormone: A chemical substance made by the thyroid gland for export into the bloodstream. The thyroid gland needs iodine to make thyroid hormones. The two most important thyroid hormones are thyroxine (T4) and triiodothyronine (T3). See the entire definition of Thyroid hormone
Thyroiditis: Inflammation of the thyroid gland which is located in front of the neck:
Titer: The degree of dilution of a substance such as an antibody, reflecting the strength of the solution. See the entire definition of Titer
Tonsillectomy: The surgical removal of both tonsils. A tonsillectomy may be performed in cases of recurrent tonsillitis, or treat sleep apnea and some speech disorders.
Toxicity: The degree to which a substance can harm humans or animals. See the entire definition of Toxicity
Transplant: The grafting of a tissue from one place to another, just as in botany a bud from one plant might be grafted onto the stem of another. The transplanting of tissue can be from one part of the patient to another (autologous transplantation), as in the case of a skin graft using the patient's own skin; or from one patient to another (allogenic transplantation), as in the case of transplanting a donor kidney into a recipient.
Trigger: Something that either sets off a disease in people who are genetically predisposed to developing the disease, or that causes a certain symptom to occur in a person who has a disease. For example, sunlight can trigger rashes in people with lupus.
Triglycerides: The major form of fat stored by the body. A triglyceride consists of three molecules of fatty acid combined with a molecule of the alcohol glycerol. Triglycerides serve as the backbone of many types of lipids (fats). Triglycerides come from the food we eat as well as from being produced by the body. See the entire definition of Triglycerides
Trimester: The nine months of pregnancy is traditionally divided into three trimesters: distinct periods of roughly three months in which different phases of fetal development take place. See the entire definition of Trimester
Tumor: An abnormal mass of tissue. Tumors are a classic sign of inflammation, and can be benign or malignant (cancerous). There are dozens of different types of tumors. Their names usually reflect the kind of tissue they arise in, and may also tell you something about their shape or how they grow. For example, a medulloblastoma is a tumor that arises from embryonic cells (a blastoma) in the inner part of the brain (the medulla). Diagnosis depends on the type and location of the tumor. Tumor marker tests and imaging may be used; some tumors can be seen (for example, tumors on the exterior of the skin) or felt (palpated with the hands). See the entire definition of Tumor
Ulcerative colitis: A relatively common disease that causes inflammation of the large intestine (the colon). The cause is unknown. See the entire definition of Ulcerative colitis
Ultrasound: High-frequency sound waves. Ultrasound waves can be bounced off of tissues using special devices. The echoes are then converted into a picture called a sonogram. Ultrasound imaging, referred to as ultrasonography, allows physicians and patients to get an inside view of soft tissues and body cavities, without using invasive techniques. Ultrasound is often used to examine a fetus during pregnancy. There is no convincing evidence for any danger from ultrasound during pregnancy.
UNOS: Acronym for the United Network for Organ Sharing, the nationwide umbrella for transplantation organ sharing in the U.S. See the entire definition of UNOS
Urinary: Having to do with the kidneys, ureters, and bladder. The urinary system represents the functional and anatomic aspects of the kidneys, ureters, and bladder.
Urinary tract: The organs of the body that produce and discharge urine. These include the kidneys, ureters, bladder, and urethra.
Urinary tract infection: Infection of the kidney, ureter, bladder, or urethra. Not everyone with a UTI has symptoms. Common symptoms include a frequent urge to urinate and a painful, burning when urinating. More females than males have UTIs. Underlying conditions that impair the normal urinary flow can lead to complicated UTIs. See the entire definition of Urinary tract infection
Urine: Liquid waste. The urine is a clear, transparent fluid. It normally has an amber color. The average amount of urine excreted in 24 hours is from 40 to 60 ounces (about 1,200 cubic centimeters). Chemically, the urine is mainly an aqueous (watery) solution of salt (sodium chloride) and substances called urea and uric acid. Normally, it contains about 960 parts of water to 40 parts of solid matter. Abnormally, it may contain sugar (in diabetes), albumen (a protein) (as in some forms of kidney disease), bile pigments (as in jaundice), or abnormal quantities of one or another of its normal components.
Vaccines: Microbial preparations of killed or modified microorganisms that can stimulate an immune response in the body to prevent future infection with similar microorganisms. These preparations are usually delivered by injection.
Vagina: The muscular canal extending from the cervix to the outside of the body. It is usually six to seven inches in length, and its walls are lined with mucus membrane. It includes two vaultlike structures, the anterior (front) vaginal fornix and the posterior (rear) vaginal fornix. The cervix protrudes slightly into the vagina, and it is through a tiny hole in the cervix (the os) that sperm make their way toward the internal reproductive organs. The vagina also includes numerous tiny glands that make vaginal secretions. See the entire definition of Vagina
Vein: A blood vessel that carries blood low in oxygen content from the body back to the heart. The deoxygenated form of hemoglobin (deoxyhemoglobin) in venous blood makes it appear dark. Veins are part of the afferent wing of the circulatory system which returns blood to the heart. See the entire definition of Vein
Viral: Of or pertaining to a virus. For example, "My daughter has a viral rash."
Viral hepatitis:Viral hepatitis is liver inflammation caused by viruses. Specific hepatitis viruses have been labeled A, B, C, D, E, F, and G. While other viruses can also cause hepatitis, their primary target is not the liver.
Virus: A microorganism smaller than a bacteria, which cannot grow or reproduce apart from a living cell. A virus invades living cells and uses their chemical machinery to keep itself alive and to replicate itself. It may reproduce with fidelity or with errors (mutations)-this ability to mutate is responsible for the ability of some viruses to change slightly in each infected person, making treatment more difficult. See the entire definition of Virus
Viruses: Small living particles that can infect cells and change how the cells function. Infection with a virus can cause a person to develop symptoms. The disease and symptoms that are caused depend on the type of virus and the type of cells that are infected.
Vitamin A: Vitamin A is retinol. Carotene compounds (found, for example, in egg yolk, butter and cream) are gradually converted by the body to vitamin A (retinol). A form of vitamin A called retinal is responsible for transmitting light sensation in the retina of the eye. See the entire definition of Vitamin A
Vitamin D: A steroid vitamin which promotes the intestinal absorption and metabolism of calcium and phosphorus. Under normal conditions of sunlight exposure, no dietary supplementation is necessary because sunlight promotes adequate vitamin D synthesis in the skin. Deficiency can lead to bone deformity (rickets) in children and bone weakness (osteomalacia) in adults. See the entire definition of Vitamin D
Vitamin E: Alpha-tocopherol, an antioxidant vitamin which binds oxygen free radicals that can cause tissue damage. Deficiency of vitamin E can lead to anemia. Vitamin E may play a possible role in preventing heart disease and cancer of the lung and prostate. See the entire definition of Vitamin E
Vitamin K: One of two naturally occurring fat-soluble vitamins (vitamin K1 and vitamin K2) needed for the clotting of blood because of an essential role in the production of prothrombin (a clotting factor). The term vitamin A may also refer to a synthetic compound that is closely related chemically to the natural vitamins K1 and K2 and has similar biological activity. See the entire definition of Vitamin K
Vitamins: The word "vitamin" was coined in 1911 by the Warsaw-born biochemist Casimir Funk (1884-1967). At the Lister Institute in London, Funk isolated a substance that prevented nerve inflammation (neuritis) in chickens raised on a diet deficient in that substance. He named the substance "vitamine" because he believed it was necessary to life and it was a chemical amine. The "e" at the end was later removed when it was recognized that vitamins need not be amines. See the entire definition of Vitamins
Weight loss: Weight loss is a decrease in body weight resulting from either voluntary (diet, exercise) or involuntary (illness) circumstances. Most instances of weight loss arise due to the loss of body fat, but in cases of extreme or severe weight loss, protein and other substances in the body can also be depleted. Examples of involuntary weight loss include the weight loss associated with cancer, malabsorption (such as from chronic diarrheal illnesses ), and chronic inflammation (such as with rheumatoid arthritis).
White blood cell: One of the cells the body makes to help fight infections. There are several types of white blood cells (leukocytes). The two most common types are the lymphocytes and neutrophils (also called polymorphonuclear leukocytes, PMNs, or "polys"). See the entire definition of White blood cell
White blood cell count (leukocyte count): The number of white blood cells (WBCs) in the blood. The WBC is usually measured as part of the CBC (complete blood count). White blood cells are the infection-fighting cells in the blood and are distinct from the red (oxygen-carrying) blood cells known as erythrocytes. There are different types of white blood cells, including neutrophils (polymorphonuclear leukocytes; PMNs), band cells (slightly immature neutrophils), T-type lymphocytes (T cells), B-type lymphocytes (B cells), monocytes, eosinophils, and basophils. All the types of white blood cells are reflected in the white blood cell count. The normal range for the white blood cell count varies between laboratories but is usually between 4,300 and 10,800 cells per cubic millimeter of blood. This can also be referred to as the leukocyte count and can be expressed in international units as 4.3 - 10.8 x 109 cells per liter. See the entire definition of White blood cell count
Windpipe: The trachea, a tube-like portion of the respiratory (breathing) tract that connects the larynx (the voicebox) with the bronchial parts of the lungs.
Gallstones are stones that form when substances in the bile harden. Gallstones (formed in the gallbladder) can be as small as a grain of sand or as large as a golf ball. There can be just one large stone, hundreds of tiny stones, or any combination. The majority of gallstones do not cause symptoms.
Hypothyroidism is any state in which thyroid hormone production is below normal. Normally, the
rate of thyroid hormone production is controlled by the brain at the pituitary.
Hypothyroidism is a very common condition and the symptoms of hypothyroidism are
often subtle.
Liver cancer is the fifth most common cancer in the world and the majority of patients with liver cancer will die within one year as a result. Patients with associated cirrhosis caused by chronic hepatitis B or C infections, alcohol, and hemochromatosis are at the greatest risk of developing liver cancer. Many patients with liver cancer do not develop symptoms until the advanced stages of the tumor which usually makes prognosis poor. The combination of an imaging study (ultrasound, CT, or MRI scans) and an elevated blood level of alpha-fetoprotein will most effectively diagnose liver cancer, while a liver biopsy can make a definitive diagnosis. Medical treatments, including chemotherapy, chemoembolization, ablation, and proton beam therapy, are not very effective. Surgical removal of the tumor or a liver transplant may be most effective in certain cases.
Cirrhosis of the liver refers to a disease in which normal liver cells are replaced by scar tissue caused by alcohol and viral hepatitis B and C. This disease leads to abnormalities in the liver's ability to handle toxins and blood flow, causing internal bleeding, kidney failure, mental confusion, coma, body fluid accumulation, and frequent infections. Symptoms include yellowing of the skin, itching, and fatigue.
Sjögren's syndrome is an autoimmune disease involving the abnormal production of extra antibodies that attack the glands and connective tissue. Sjögren's syndrome with gland inflammation (resulting dry eyes and mouth, etc.) that is not associated with another connective tissue disease is referred to as primary Sjögren's syndrome. Sjögren's syndrome that is also associated with a connective tissue disease, such as rheumatoid arthritis, systemic lupus erythematosus, or scleroderma, is referred to as secondary Sjögren's syndrome. Though there is no cure for Sjögren's syndrome, the symptoms may be treated by using lubricating eye ointments, drinking plenty of water, humidifying the air, and using glycerin swabs. Medications are also available to treat dry eye and dry mouth.
Edema is the swelling of tissues as a result of excess water accumulations. Peripheral edema occurs in the feet and legs. There are two types of edema, non-pitting edema and pitting edema. Causes of pitting edema is caused by systemic diseases, most commonly involving the heart, liver, and kidneys. Local conditions that cause edema are thrombophlebitis and varicose veins. Edema is generally treated with medication.
Itching can be a common problem. Itches can be localized or generalized. There are many causes of itching to include: infection (jock itch, vaginal itch), disease (hyperthyroidism, liver or kidney), reactions to drugs, and skin infestations (pubic or body lice). Treatment for itching varies depending on the cause of the itch.
Jaundice is a yellowish staining of the skin and whites of the eyes (sclerae) with bilirubin, the pigment found in bile. Jaundice can be an indicator of liver or gallbladder disease, or it may result from the rupture of red blood cells (hemolysis).
Ulcerative colitis is a chronic inflammation of the colon. Symptoms include abdominal pain, diarrhea, and rectal bleeding. Ulcerative colitis is closely related to Crohn's disease, and together they are referred to as inflammatory bowel disease. Treatment depends upon the type of ulcerative colitis diagnosed.
Learn about osteoporosis, a condition characterized by the loss of bone density, which leads to an increased risk of bone fracture. Unless one experiences a fracture, a person may have osteoporosis for decades without knowing it. Treatment for osteoporosis may involve medications that stop bone loss and increase bone strength and bone formation, as well as quitting smoking, regular exercise, cutting back on alcohol intake, and eating a calcium- and vitamin D-rich balanced diet.
Scleroderma is an autoimmune disease of the connective tissue. It is characterized by the formation of scar tissue (fibrosis) in the skin and organs of the body, leading to thickness and firmness of involved areas. Scleroderma is also referred to as systemic sclerosis, and the cause is unknown. Treatment of scleroderma is directed toward the individual features that are most troubling to the patient.
The liver is the largest solid organ in the body, and is actually an gland. The liver has a wide variety of critical functions such as manufacturing proteins and metabolizing fats and carbohydrates. The liver also eliminates harmful biochemical waste products from the body (alcohol, drugs, toxins). The liver secretes bile that aids in digestion. Examples of diseases of the liver include cirrhosis, hepatitis, cancer, and fatty liver. Symptoms of liver disease include bleeding, easy bruising, edema, fatigue, and jaundice.
Digestion is the complex process of turning food you eat into the energy you need to survive. The digestive process also involves creating waste to be eliminated, and is made of a series of muscles that coordinate the movement of food.
Thyroiditis is the inflammation of the thyroid gland. The inflamed thyroid gland can release an excess of thyroid hormones into the blood stream, resulting in a temporary hyperthyroid state. Some forms of thyroiditis can be diagnosed based on tenderness and enlargement of the thyroid gland. A thyroid scan sometimes is used in making the diagnosis. Thyroiditis can also be diagnosed with a biopsy of the thyroid gland.
Sjögren's syndrome involves inflammation of glands
and other tissues of the body.
About 90% of Sjögren's syndrome patients are female.
Sjögren's syndrome can be complicated by infections
of the eyes, breathing passages, and mouth.
Sjögren's syndrome is typically associated with
antibodies against a variety of body tissues (autoantibodies).
Diagnosis of Sjögren's syndrome can be aided by a
saliva-gland biopsy.
Treatment of patients with Sjögren's syndrome is directed toward the particular areas of the body that are involved and complications, such
as infection.
What is Sjögren's syndrome?
Sjögren's syndrome is an autoimmune disease characterized by dryness of the
mouth and eyes. Autoimmune diseases feature the abnormal pr...