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February 10, 2012

Sickle Cell Disease (Sickle Cell Anemia) Glossary of Terms

The following are health and medical definitions of terms that appear in the Sickle Cell Disease (Sickle Cell Anemia) article.

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.
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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).

Acute: Of abrupt onset, in reference to a disease. Acute often also connotes an illness that is of short duration, rapidly progressive, and in need of urgent care.
See the entire definition of Acute

Amniocentesis: Procedure used in prenatal diagnosis to obtain amniotic fluid which can be used for genetic and other diagnostic tests. Informally called an "amnio."

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

Anesthesia: Loss of feeling or awareness. A general anesthetic puts the person to sleep. A local anesthetic causes loss of feeling in a part of the body such as a tooth or an area of skin without affecting consciousness. Regional anesthesia numbs a larger part of the body such as a leg or arm, also without affecting consciousness. The term "conduction anesthesia" encompasses both local and regional anesthetic techniques. Many surgical procedures can be done with conduction anesthesia without significant pain. In many situations, such as a C-section, conduction anesthesia is safer and therefore preferable to general anesthesia. However, there are also many types of surgery in which general anesthesia is clearly appropriate.

Angiogram: An x-ray of blood vessels which can be seen because the patient receives an injection of dye to outline the vessels on the x-ray.

Antibiotic: A drug used to treat infections caused by bacteria and other microorganisms. Originally, an antibiotic was a substance produced by one microorganism that selectively inhibits the growth of another. Synthetic antibiotics, usually chemically related to natural antibiotics, have since been produced that accomplish comparable tasks.
See the entire definition of Antibiotic

Appendicitis: Inflammation of the appendix, the small worm-like projection from the first part of the colon. Appendicitis usually involves infection of the appendix by bacteria that invade it and infect the wall of the appendix. Appendicitis can progress to produce an abscess (a pocket of pus) and even peritonitis (inflammation of the lining of the abdomen and pelvis).
See the entire definition of Appendicitis

Arms: An appendage in anatomy and in clinical trials. See: Arm.

Arthritis: Inflammation of a joint. When joints are inflamed they can develop stiffness, warmth, swelling, redness and pain. There are over 100 types of arthritis. (see osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, lupus, gout, pseudogout).

Aseptic: The absence of microorganisms. By contrast, something that just discourages the growth of microorganisms is antiseptic.

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Aseptic necrosis: Condition in which poor blood supply to an area of bone leads to bone death. Also called avascular necrosis and osteonecrosis.

Aspirin: A good example of a tradename that entered into the language, Aspirin was once the Bayer trademark for acetylsalicylic acid.
See the entire definition of Aspirin

Autosomal: Pertaining to a chromosome that is not a sex chromosome; relating to any one of the chromosomes save the sex chromosomes.
See the entire definition of Autosomal

Autosomal dominant: A pattern of inheritance in which an affected individual has one copy of a mutant gene and one normal gene on a pair of autosomal chromosomes. (In contrast, autosomal recessive diseases require that the individual have two copies of the mutant gene.) Individuals with autosomal dominant diseases have a 50-50 chance of passing the mutant gene and therefore the disorder onto each of their children. Examples of autosomal dominant diseases include Huntington disease, neurofibromatosis, and polycystic kidney disease.

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

Biofeedback: A method of treatment that uses monitors to feed back to patients physiological information of which they are normally unaware. By watching the monitor, patients can learn by trial and error to adjust their thinking and other mental processes in order to control "involuntary" bodily processes such as blood pressure, temperature, gastrointestinal functioning, and brain wave activity.
See the entire definition of Biofeedback

Blindness: Loss of useful sight. Blindness can be temporary or permanent. Damage to any portion of the eye, the optic nerve, or the area of the brain responsible for vision can lead to blindness. There are numerous (actually, innumerable) causes of blindness. The current politically correct terms for blindness include visually handicapped and visually challenged.

Blood transfusion: The transfer of blood or blood components from one person (the donor) into the bloodstream of another person (the recipient). This may be done as a lifesaving maneuver to replace blood cells or blood products lost through bleeding. Transfusion of your own blood (autologous) is the safest method but requires advance planning and not all patients are eligible. Directed donor blood allows the patient to receive blood from known donors. Volunteer donor blood is usually most readily available and, when properly tested has a low incidence of adverse events. Blood conserving techniques are an important aspect of limiting transfusion requirements.
See the entire definition of Blood transfusion

Bone marrow: The soft blood-forming tissue that fills the cavities of bones and contains fat and immature and mature blood cells, including white blood cells, red blood cells, and platelets. Diseases or drugs that affect the bone marrow can affect the total counts of these cells.

Bone marrow transplantation: See: Bone marrow transplant.

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."

Carbon dioxide: A gas which is the byproduct of cellular metabolism and which collects in the tissues, is cleared from the tissues by the blood within the veins, is carried by the hemoglobin in the red blood cells, and removed from the body via the lungs in the exhaled air. Abbreviated CO2.

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.
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Cholecystitis: Inflammation of the gallbladder, a complication of gallstones which are formed by cholesterol and pigment (bilirubin) in bile. (Bile is produced in the liver and stored in the gallbladder). Cholecystitis is frequently associated with infection in the gallbladder. Risk factors for cholesterol gallstones include age, obesity, female gender, multiple pregnancies, birth control pills, and heredity. The most common symptom is pain in the upper abdomen. Diagnosis is usually made with ultrasound of the abdomen. Some patients have no symptoms. Patients with mild and infrequent symptoms may consider oral medication to dissolve gallstones. Surgery (standard or laparoscopic) is considered for patients with severe symptoms and for patient with cholecystitis.

Chorionic villus sampling: A procedure for first-trimester prenatal diagnosis. Chorionic villus sampling may be done between the eighth and tenth weeks of pregnancy. The aim is to diagnose severe abnormalities afflicting the fetus. In the procedure, tissue is withdrawn from the villi (vascular fingers) of the chorion, a part of the placenta, and examined. Chorionic villus sampling is referred to commonly as CVS.

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.
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Circulation: The movement of fluid in a regular or circuitous course. Although the noun "circulation" does not necessarily refer to the circulation of the blood, for all practical purposes today it does. Heart failure is an example of a problem with the circulation.

Coma: A state of deep unarousable unconsciousness.
See the entire definition of Coma

Congestion: An abnormal or excessive accumulation of a body fluid. The term is used broadly in medicine. Examples include nasal congestion (excess mucus and secretions in the air passages of the nose) seen with a common cold and congestion of blood in the lower extremities seen with some types of heart failure.

Cough: A rapid expulsion of air from the lungs typically in order to clear the lung airways of fluids, mucus, or material. Also called tussis.

Dactylitis: Inflammation of a digit (either a finger or a toe).
See the entire definition of Dactylitis

Dehydration: Excessive loss of body water. Diseases of the gastrointestinal tract that cause vomiting or diarrhea may, for example, lead to dehydration. There are a number of other causes of dehydration including heat exposure, prolonged vigorous exercise (e.g., in a marathon), kidney disease, and medications (diuretics).
See the entire definition of Dehydration

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.
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DNA: Deoxyribonucleic acid. One of two types of molecules that encode genetic information. (The other is RNA. In humans DNA is the genetic material; RNA is transcribed from it. In some other organisms, RNA is the genetic material and, in reverse fashion, the DNA is transcribed from it.)
See the entire definition of DNA

Elbow: The juncture of the long bones in the middle portion of the arm. The bone of the upper arm (humerus) meets both the ulna (the inner bone of the forearm) and radius (the outer bone of the forearm) to form a hinge joint at the elbow. The radius and ulna also meet one another in the elbow to permit a small amount of rotation of the forearm. The elbow therefore functions to move the arm like a hinge (forward and backward) and in rotation (outward and inward). The biceps muscle is the major muscle that flexes the elbow hinge, and the triceps muscle is the major muscle that extends it. The primary stability of the elbow is provided by the ulnar collateral ligament, located on the medial (inner) side of the elbow. The outer bony prominence of the elbow is the lateral epicondyle, a part of the humerus bone. Tendons attached to this area can be injured, causing inflammation or tendonitis (lateral epicondylitis, or tennis elbow). The inner portion of the elbow is a bony prominence called the medial epicondyle of the humerus. Additional tendons from muscles attach here and can be injured, likewise causing inflammation or tendonitis (medial epicondylitis, or golfer's elbow). See also: Elbow bursitis; Elbow pain; Nursemaid's elbow.

Electrophoresis: A process by which molecules (such as proteins, DNA, or RNA fragments) can be separated according to size and electrical charge by applying an electric current to them. Each kind of molecule travels through the medium at a different rate, depending on its electrical charge and molecular size.
See the entire definition of Electrophoresis

Father: (1) The male parent. (2) One who originates. For example, "Wilhelm Roentgen is considered the father of radiology." (3) To produce offspring as a male. (4) To provide paternal protection and guidance to children.

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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.
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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

Flu: Short for influenza. The flu is caused by viruses that infect the respiratory tract which are divided into three types, designated A, B, and C. Most people who get the flu recover completely in 1 to 2 weeks, but some people develop serious and potentially life-threatening medical complications, such as pneumonia. Much of the illness and death caused by influenza can be prevented by annual influenza vaccination.

Folic acid: One of the B vitamins that is a key factor in the synthesis (the making) of nucleic acid (DNA and RNA).
See the entire definition of Folic acid

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

Gene: The basic biological unit of heredity. A segment of deoxyribonucleic acid (DNA) needed to contribute to a function.
See the entire definition of Gene

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.

Genetic counseling: An educational counseling process for individuals and families who have a genetic disease or who are at risk for such a disease. Genetic counseling is designed to provide patients and their families with information about their condition and help them make informed decisions.
See the entire definition of Genetic counseling

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.
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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).

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

Hemoglobin S: The most common type of abnormal hemoglobin and the basis of sickle cell trait and sickle cell anemia.
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Hemolysis: The destruction of red blood cells which leads to the release of hemoglobin from within the red blood cells into the blood plasma.
See the entire definition of Hemolysis

Hemorrhage: Bleeding or the abnormal flow of blood.
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Hepatitis: Inflammation of the liver from any cause.
See the entire definition of Hepatitis

Hepatomegaly: An enlarged liver. "Hepato-" comes from the Greek "hepatikos" (of the liver) + "megaly" from the Greek "megas" (big or great) = bigness of the liver.

Hydroxyurea: A drug that inhibits the synthesis of DNA and so is classified as an antimetabolite. Hydroxyurea is used to treat a number of diseases, including chronic myeloid leukemia (CML), polycythemia vera, carcinoma of the head and neck, ovary, and cervix, melanoma, and sickle cell disease. Hydroxyurea is taken orally and is inexpensive.

Ibuprofen: A non-steroidal anti-inflammatory drug (NSAID) commonly used to treat pain, swelling, and fever. Common brand names for Ibuprofen include Advil, Motrin, and Nuprin.

Immune: Protected against infection. The Latin immunis means free, exempt.

Impotence: A common problem among men characterized by the consistent inability to sustain an erection sufficient for sexual intercourse or the inability to achieve ejaculation, or both. Impotence can vary. It can involve a total inability to achieve an erection or ejaculation, an inconsistent ability to do so, or a tendency to sustain only very brief erections.
See the entire definition of Impotence

Infarction: The formation of an infarct, an area of tissue death due to a local lack of oxygen.
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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

Influenza: The flu is caused by viruses that infect the respiratory tract which are divided into three types, designated A, B, and C. Most people who get the flu recover completely in 1 to 2 weeks, but some people develop serious and potentially life-threatening medical complications, such as pneumonia. Much of the illness and death caused by influenza can be prevented by annual influenza vaccination.

Inheritance: Not something that is contained in a will, but rather a gene, chromosome or genome that is transmitted from parent to child.
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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.

Internal medicine: A medical specialty dedicated to the diagnosis and medical treatment of adults. A physician who specializes in internal medicine is referred to as an internist. A minimum of seven years of medical school and postgraduate training are focused on learning the prevention, diagnosis, and treatment of diseases of adults. Subspecialties of internal medicine include allergy and immunology, cardiology (heart), endocrinology (hormone disorders), hematology (blood disorders), infectious diseases, gastroenterology (diseases of the gut), nephrology (kidney diseases), oncology (cancer), pulmonology (lung disorders), and rheumatology (arthritis and musculoskeletal disorders).

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Iron: An essential mineral. Iron is necessary for the transport of oxygen (via hemoglobin in red blood cells) and for oxidation by cells (via cytochrome). Deficiency of iron is a common cause of anemia. Food sources of iron include meat, poultry, eggs, vegetables and cereals (especially those fortified with iron). According to the National Academy of Sciences, the Recommended Dietary Allowances of iron are 15 milligrams per day for women and 10 milligrams per day for men. Iron overload can damage the heart, liver, gonads and other organs. Iron overload is a particular risk in people who may have certain genetic conditions (hemochromatosis) sometimes without knowing it and also in people receiving recurrent blood transfusions. Iron supplements meant for adults (such as pregnant women) are a major cause of poisoning in children.

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.
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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.


See the entire definition of Kidney

Knee: The knee is a joint which has three parts. The thigh bone (the femur) meets the large shin bone (the tibia) to form the main knee joint. This joint has an inner (medial) and an outer (lateral) compartment. The kneecap (the patella) joins the femur to form a third joint, called the patellofemoral joint. The patella protects the front of the knee joint.
See the entire definition of Knee

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."

Laser: A powerful beam of light that can produce intense heat when focused at close range. Lasers are used in medicine in microsurgery, cauterization, for diagnostic purposes, etc. For example, lasers are employed in microsurgery to cut tissue and remove tissue.
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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

Lethal: Deadly, fatal, capable of causing death, death-dealing. The word "lethal" comes from the Latin "letum" meaning "death or destruction."

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.


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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.

Magnesium: A mineral involved in many processes in the body including nerve signaling, the building of healthy bones, and normal muscle contraction. About 350 enzymes are known to depend on magnesium.
See the entire definition of Magnesium

Malaria: An infectious disease caused by protozoan parasites from the Plasmodium family that can be transmitted by the sting of the Anopheles mosquito or by a contaminated needle or transfusion. Falciparum malaria is the most deadly type.
See the entire definition of Malaria

Marrow: The bone marrow.

Meningitis: Inflammation of the meninges, usually due to a bacterial infection but sometimes from viral, protozoan, or other causes (in some cases the cause cannot be determined).
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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.

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.

Molecule: The smallest unit of a substance that can exist alone and retain the character of that substance.

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."

Narcotic: 1. A drug that causes insensibility or stupor. A narcotic induces narcosis, from the Greek "narke" for "numbness or torpor."
2. A drug such as marijuana which is subject to regulatory restrictions comparable to those for addictive narcotics.

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.

Necrosis: The death of living cells or tissues. Necrosis can be due, for example, to ischemia (lack of blood flow). From the Greek "nekros" (dead body).

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.

Offspring: The offspring are strictly speaking the progeny, or young, born to a person.
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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.

Osteomyelitis: Inflammation of the bone due to infection, for example by the bacteria salmonella or staphylococcus. Osteomyelitis is sometimes a complication of surgery or injury, although infection can also reach bone tissue through the bloodstream. Both the bone and the bone marrow may be infected. Symptoms include deep pain and muscle spasms in the area of inflammation, and fever. Treatment is by bed rest, antibiotics (usually injected locally), and sometimes surgery to remove dead bone tissue.

Osteonecrosis: Bone death resulting from poor blood supply to an area of bone. Also known as aseptic necrosis or avascular necrosis.

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.
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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.
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Pathogenesis: The development of a disease. The origin of a disease and the chain of events leading to that disease.

Pelvic: Having to do with the pelvis, the lower part of the abdomen, located between the hip bones.

Pelvic pain: Pain perceived in the area of the pelvis, the lower part of the abdomen located between the hip bones. The term pelvic pain is most commonly used to refer to pain arising from reproductive organs (uterus, fallopian tubes, ovaries, vagina) in women. In this sense pelvic pain can have numerous causes, including menstrual cramps; pain from a rupture of an ectopic pregnancy, ovarian cyst, or other mass; endometriosis; and pelvic inflammatory disease . Nongynecologic sources of pelvic pain can include urinary tract infections, intestinal obstruction, colitis, tumors, appendicitis, or a number of other conditions.

Penis: The external male sex organ used to copulate and ejaculate semen and to convey urine outside the body.
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Physical therapy: A branch of rehabilitative health that uses specially designed exercises and equipment to help patients regain or improve their physical abilities. Physical therapists work with many types of patients, from infants born with musculoskeletal birth defects, to adults suffering from sciatica or the after- effects of injury, to elderly post-stroke patients.

Placenta: A temporary organ joining the mother and fetus, the placenta transfers oxygen and nutrients from the mother to the fetus, and permits the release of carbon dioxide and waste products from the fetus. It is roughly disk-shaped, and at full term measures about seven inches in diameter and a bit less than two inches thick. The upper surface of the placenta is smooth, while the under surface is rough. The placenta is rich in blood vessels.
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Pneumonia: Inflammation of one or both lungs with consolidation. Pneumonia is frequently but not always due to infection. The infection may be bacterial, viral, fungal or parasitic. Symptoms may include fever, chills, cough with sputum production, chest pain, and shortness of breath.

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.
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Pregnant: The state of carrying a developing fetus within the body.
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Prenatal: Occurring or existing before birth.
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Prenatal diagnosis: Diagnosis before birth. Methods for prenatal diagnosis include ultrasound of the uterus, placenta, and/or developing fetus; chorionic villus sampling (CVS) to obtain tissue for chromosome or biochemical analysis; and amniocentesis to obtain amniotic fluid for the analysis of chromosomes, enzymes, or DNA. A growing number of birth defects and diseases can be diagnosed prenatally, and in some cases treated before birth. Also known as antenatal diagnosis.

Priapism: Abnormally persistent erection of the penis in the absence of sexual desire. Priapism can occur in persons with sickle cell anemia.
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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.
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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.
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Pulmonary: Having to do with the lungs. (The word comes from the Latin pulmo for lung).

Range of motion: The range through which a joint can be moved, usually its range of flexion and extension. Due to an injury, the knee may for example lack 10 degrees of full extension.

Recessive: A condition that appears only in individuals who have received two copies of a mutant gene, one copy from each parent. The individuals with a double dose of the mutated gene are called homozygotes. Their parents, each with a single dose of the mutated gene, appear normal and are called heterozygotes, or gene carriers.
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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).
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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).
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Remedy: Something that consistently helps treat or cure a disease. From the Latin "remedium" meaning that which heals again (and again).
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Retina: The retina is the nerve layer that lines the back of the eye, senses light, and creates impulses that travel through the optic nerve to the brain. There is a small area, called the macula, in the retina that contains special light-sensitive cells. The macula allows us to see fine details clearly.
See the entire definition of Retina

Retinal: Pertaining to the retina, the extraordinary layer of neurons (nerve cells) that line the back of the eye, which can sense light and create impulses capable of voyaging through the optic nerve to the brain where the impulses are recognized as an image.
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Retinal detachment: A separation of the retina from its connection at the back of the eye. The separation usually results from a tear (that is, a rent or rip, not a tear drop) in the retina. The tear often occurs when the vitreous gel pulls loose or separates from its attachment to the retina, usually in the outside edges of the eye. The vitreous is a clear gel that fills most of the inside of the eye between the retina and the lens. If the retina is weak when the vitreous gel pulls loose, the retina will tear. This rip is sometimes accompanied by bleeding, or hemorrhage, if a blood vessel is also torn.
See the entire definition of Retinal detachment

Retinopathy: Any disease of the retina, the light-sensitive membrane at the back of the eye. The type of retinopathy is often specified. Arteriosclerotic retinopathy is retinal disease due to arteriosclerosis ("hardening of the arteries"). Diabetic retinopathy is retinal disease associated with diabetes. Hypertensive retinopathy is retinal disease due to high blood pressure. Etc.

Rupture: A break or tear in any organ (such as the spleen) or soft tissue (such as the achilles tendon). Rupture of the appendix is more likely among uninsured and minority children when they develop appendicitis.

Salmonella: A group of bacteria that cause typhoid fever and a number of other illnesses, including food poisoning, gastroenteritis and enteric fever from contaminated food products.
See the entire definition of Salmonella

Sex chromosome: The X chromosome or the Y chromosome, in humans. The sex chromosomes determine the sex of an individual. As a general rule, normal females have two X chromosomes while normal males have an X and a Y chromosome. The sex chromosomes evolved from an ancient pair of autosomal chromosomes. The X is considerably larger and richer in genes than the Y. The X contains 153 M bp (mega base pairs) and 1095 genes while the Y contains 50 M bp and 148 genes. The sex chromosomes, by convention, are the 23rd and last pair of chromosomes in a normal human karyotype.

Shock: In medicine, shock is a critical condition brought on by a sudden drop in blood flow through the body. There is failure of the circulatory system to maintain adequate blood flow. This sharply curtails the delivery of oxygen and nutrients to vital organs. It also compromises the kidney and so curtails the removal of wastes from the body. Shock can be due to a number of different mechanisms including not enough blood volume (hypovolemic shock) and not enough output of blood by the heart (cardiogenic shock). The signs and symptoms of shock include low blood pressure (hypotension), overbreathing (hyperventilation), a weak rapid pulse, cold clammy grayish-bluish (cyanotic) skin, decreased urine flow (oliguria), and mental changes (a sense of great anxiety and foreboding, confusion and, sometimes, combativeness).
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Sibling: A brother or sister.

Sickle cell anemia: A genetic blood disease due to the presence of an abnormal form of hemoglobin, namely hemoglobin S. Hemoglobin is the molecule in red blood cells that transports oxygen from the lungs to the farthest areas of the body.
See the entire definition of Sickle cell anemia

Sickle cell disease: A genetic blood disorder caused by the presence of an abnormal form of hemoglobin. These hemoglobin molecules tend to aggregate after unloading oxygen forming long, rod-like strictures that force the red cells to assume a sickle shape. Unlike normal red cells, which are usually smooth and malleable, the sickle red cells cannot squeeze through small blood vessels. When the sickle cells block small blood vessels, the organs are deprived of blood and oxygen. This leads to periodic episodes of pain and damages the vital organs. Sickle red cells die after only about 10 to 20 days. Instead of the usual 120 days or so. Because they cannot be replaced fast enough, the blood is chronically short of red cells, causing anemia. The gene for sickle cell anemia must be inherited from both parents for the illness to occur in children. A child with only one copy of the gene may have sickle-cell traits but no symptoms of illness.
See the entire definition of Sickle cell disease

Sickle cell trait: The condition in which a person has one copy of the gene for sickle cell (and is called a sickle heterozygote) but does not have sickle cell disease (which requires two copies of the sickle cell gene). If two people with sickle cell trait mate and have children together, each of their children has a one in four chance (25%) of having sickle cell disease.
See the entire definition of Sickle cell trait

Sodium: The major positive ion (cation) in fluid outside of cells. The chemical notation for sodium is Na+. When combined with chloride, the resulting substance is table salt.
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Speech therapy: The treatment of speech and communication disorders. The approach used depends on the disorder. It may include physical exercises to strengthen the muscles used in speech (oral-motor work), speech drills to improve clarity, or sound production practice to improve articulation.
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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.

Splenomegaly: Enlargement of the spleen.
See the entire definition of Splenomegaly

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

Stress: Forces from the outside world impinging on the individual. Stress is a normal part of life that can help us learn and grow. Conversely, stress can cause us significant problems.
See the entire definition of Stress

Stroke: The sudden death of some brain cells due to a lack of oxygen when the blood flow to the brain is impaired by blockage or rupture of an artery to the brain. A stroke is also called a cerebrovascular accident or, for short, a CVA.
See the entire definition of Stroke

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.

Therapy: The treatment of disease.
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Topical: Pertaining to a particular surface area. A topical agent is applied to a certain area of the skin and is intended to affect only the area to which it is applied. Whether its effects are indeed limited to that area depends upon whether the agent stays where it is put or is absorbed into the blood stream.

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Trait: In genetics, a trait refers to any genetically determined characteristic. In technical terms, a genetic trait is amenable to segregation analysis rather than quantitative analysis.
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Transfusion: The transfer of blood or blood products from one person (the donor) into another person (the recipient's) bloodstream. In most situations, this is done as a lifesaving maneuver to replace blood cells or blood products lost through severe bleeding. Transfusion of your own blood (autologous) is the safest method but requires planning ahead and not all patients are eligible. Directed donor blood allows the patient to receive blood from known donors. Volunteer donor blood is usually most readily available and, when properly tested has a low incidence of adverse events.
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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.

Trauma: Any injury, whether physically or emotionally inflicted. "Trauma" has both a medical and a psychiatric definition. Medically, "trauma" refers to a serious or critical bodily injury, wound, or shock. This definition is often associated with trauma medicine practiced in emergency rooms and represents a popular view of the term. In psychiatry, "trauma" has assumed a different meaning and refers to an experience that is emotionally painful, distressful, or shocking, which often results in lasting mental and physical effects.
See the entire definition of Trauma

Tubes: The "tubes" are medically known as the Fallopian tubes. There are two Fallopian tubes, one on each side, which transport the egg from the ovary to the uterus (the womb). The Fallopian tubes have small hair-like projections called cilia on the cells of the lining.
See the entire definition of Tubes

Ulceration: The process or fact of being eroded away, as by an ulcer.

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.

Vaccination: Injection of a killed microbe in order to stimulate the immune system against the microbe, thereby preventing disease. Vaccinations, or 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 only immunize against bacterial diseases, it is generally possible to use 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 Vaccines (in the plural) and Vaccine of a specific type (such Vaccine, Polio).

Vertebrae: The preferred plural of vertebra. (The alternate plural is vertebras.) See also: Cervical vertebrae; Coccygeal vertebrae; Lumbar vertebrae; Sacral vertebrae; and Thoracic vertebrae.

Villus: 1. A tiny finger-like or hair-like projection. 2. A small vascular protrusion.
Villus is the Latin word for shaggy hair or fleece. The plural is villi.

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.

X-ray: 1. High-energy radiation with waves shorter than those of visible light. X-rays possess the properties of penetrating most substances (to varying extents), of acting on a photographic film or plate (permitting radiography), and of causing a fluorescent screen to give off light (permitting fluoroscopy). In low doses X-rays are used for making images that help to diagnose disease, and in high doses to treat cancer. Formerly called a Roentgen ray. 2. An image obtained by means of X-rays.

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Sickle Cell Disease (Sickle Cell Anemia)

Aseptic necrosis facts

  • Aseptic necrosis is a bone condition that results from poor blood supply to an area of bone, causing localized bone death.
  • Aseptic necrosis can be caused by trauma, damage to the blood vessels that supply bone its oxygen, poor blood circulation to the bone, abnormally thick blood (hypercoagulable state), and atherosclerosis or inflammation of the blood vessel walls (vasculitis).
  • Steroid medications (cortisone, such as prednisone [Deltasone, Liquid Pred] and methylprednisolone [Medrol, Depo-Medrol]) are the most common medications to cause aseptic necrosis.
  • Risk factors for aseptic necrosis include alcoholism, cortisone medications, Cushing's syndrome, radiation exposure, sickle cell disease, pancreatitis, Gaucher disease, and systemic lupus erythematosus.
  • Aseptic necrosis may or may not cause pain.
  • The treatment of aseptic necrosis is critically dependent on the stage of the ...

Read the Aseptic Necrosis article »







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