Vitamins and Calcium Supplements Glossary of Terms

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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.
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Acne: Localized skin inflammation as a result of overactivity of the oil glands at the base of hair follicles. Acne happens when oil (sebaceous) glands come to life around puberty, when these glands are stimulated by male hormones that are produced in the adrenal glands of both boys and girls.
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Alcohol: An organic chemical in which one or more hydroxyl (OH) groups are attached to carbon (C) atoms in place of hydrogen (H) atoms. Common alcohols include ethyl alcohol or ethanol (found in alcoholic beverages), methyl alcohol or methanol (can cause blindness) and propyl alcohol or propanol (used as a solvent and antiseptic ). Rubbing alcohol is a mixture of acetone , methyl isobutyl ketone, and ethyl alcohol. In everyday talk, alcohol usually refers to ethanol as, for example, in wine, beer, and liquor. It can cause changes in behavior and be addictive.
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Alcohol abuse: Use of alcoholic beverages to excess, either on individual occasions ("binge drinking") or as a regular practice. For some individuals-children or pregnant women, for example-almost any amount of alcohol use may be legally considered "alcohol abuse," depending on local laws. Heavy alcohol abuse can cause physical damage and death.

Alcoholism: Physical dependence on alcohol to the extent that stopping alcohol use will bring on withdrawal symptoms. In popular and therapeutic parlance, the term may also be used to refer to ingrained drinking habits that cause health or social problems. Treatment requires first ending the physical dependence, then making lifestyle changes that help the individual avoid relapse . In some cases, medication or hospitalization are needed. Alcohol dependence can have many serious effects on the brain , liver , and other organs of the body.
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Allergy : A misguided reaction to foreign substances by the immune system , the body system of defense against foreign invaders, particularly pathogens (the agents of infection ). The allergic reaction is misguided in that these foreign substances are usually harmless. The substances that trigger allergy are called allergen. Examples include pollens , dust mite, molds , danders , and certain foods. People prone to allergies are said to be allergic or atopic .
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Alzheimer's disease: See: Alzheimer disease.

Amino acid: One of the 20 building blocks of protein . The sequence of amino acids in a protein and, hence, the function of that protein are determined by the genetic code in the DNA .
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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.
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Antioxidant: Any substance that reduces oxidative damage (damage due to oxygen ) such as that caused by free radicals. Free radicals are highly reactive chemicals that attack molecules by capturing electrons and thus modifying chemical structures.
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Arms: An appendage in anatomy and in clinical trials. See: Arm.

Arteriosclerosis: Hardening and thickening of the walls of the arteries. Arteriosclerosis can occur because of fatty deposits on the inner lining of arteries (atherosclerosis), calcification of the wall of the arteries, or thickening of the muscular wall of the arteries from chronically elevated blood pressure (hypertension).

Ascorbic acid: Vitamin C, an essential nutrient found mainly in fruits and vegetables. The body requires it to form and maintain bones, blood vessels, and skin. Like other vitamins, ascorbic acid is an organic compound. An organic compound is a substance that (1) occurs in living things, or organisms (hence, the word "organic") and (2) contains the elements carbon and oxygen (hence, the word "compound," meaning combination of elements).
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Aspirin: A good example of a tradename that entered into the language, Aspirin was once the Bayer trademark for acetylsalicylic acid .
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Atherosclerosis: A process of progressive thickening and hardening of the walls of medium-sized and large arteries as a result of fat deposits on their inner lining.
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Atrophy: Wasting away or diminution. Muscle atrophy is wasting of muscle, decrease in muscle mass.
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Attention: The ability to focus selectively on a selected stimulus, sustaining that focus and shifting it at will. The ability to concentrate.
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Balance: A biological system that enables us to know where our bodies are in the environment and to maintain a desired position. Normal balance depends on information from the inner ear, other senses (such as sight and touch) and muscle movement.
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Beriberi: A syndrome characterized by inflammation of multiple nerves (polyneuritis), heart disease (cardiopathy), and edema (swelling) due to a deficiency of thiamine (vitamin B1) in the diet.
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Beta carotene: A vitamin that acts as an antioxidant, protecting cells against oxidation damage. Beta carotene is converted by the body to vitamin A. Food sources of beta carotene include vegetables such as carrots, sweet potatoes, spinach and other leafy green vegetables; and fruit such as cantaloupes and apricots. Excessive carotene in the diet can color the skin yellow, a condition called carotenemia. Carotenemia is sometimes seen in infants fed too many mashed carrots and is a reversible condition. Beta carotene supplements have been found not to reduce the risks for cancer or heart disease.
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Birth control : Birth control is the use of any practices, methods, or devices to prevent pregnancy from occurring in a sexually active woman. Also referred to as family planning, pregnancy prevention, fertility control, or contraception; birth control methods are designed either to prevent fertilization of an egg or implantation of a fertilized egg in the uterus.
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Birth defect: Any defect present in a baby at birth, irrespective of whether the defect is caused by a genetic factor or by prenatal events that are not genetic.
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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.
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Blood: The familiar red fluid in the body that contains white and red blood cells, platelets, proteins, and other elements. The blood is transported throughout the body by the circulatory system. Blood functions in two directions: arterial and venous. Arterial blood is the means by which oxygen and nutrients are transported to tissues while venous blood is the means by which carbon dioxide and metabolic by-products are transported to the lungs and kidneys, respectively, for removal from the body.

Blood pressure: The blood pressure is the pressure of the blood within the arteries. It is produced primarily by the contraction of the heart muscle. It's measurement is recorded by two numbers. The first (systolic pressure) is measured after the heart contracts and is highest. The second (diastolic pressure) is measured before the heart contracts and lowest. A blood pressure cuff is used to measure the pressure. Elevation of blood pressure is called "hypertension".

Bone: Bone is the substance that forms the skeleton of the body. It is composed chiefly of calcium phosphate and calcium carbonate . It also serves as a storage area for calcium, playing a large role in calcium balance in the blood.
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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.

Bowel: Another name for the intestine . The small bowel and the large bowel are the small intestine and large intestine , respectively.
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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."
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Breast : The breast refers to the front of the chest or, more specifically, to the mammary gland. The mammary gland is a milk producing gland. It is composed largely of fat. Within the mammary gland is a complex network of branching ducts. These ducts exit from sac-like structures called lobules, which can produce milk in females. The ducts exit the breast at the nipple.
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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.

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.

Cancer: An abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread).
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Carbohydrates: Mainly sugars and starches, together constituting one of the three principal types of nutrients used as energy sources (calories) by the body. Carbohydrates can also be defined chemically as neutral compounds of carbon, hydrogen and oxygen.
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Carpal tunnel syndrome: A type of compression neuropathy (nerve damage) caused by compression and irritation of the median nerve in the wrist. The nerve is compressed within the carpal tunnel, a bony canal in the palm side of the wrist that provides passage for the median nerve to the hand. The irritation of the median nerve is specifically due to pressure from the transverse carpal ligament.
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Celiac sprue: See: Celiac disease.

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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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.
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Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time.
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Chronic pancreatitis : A form of pancreatitis in which there is persistent inflammation of the pancreas .

Cod liver oil: An oil extracted from the liver of the cod. Cod liver oil was once given religiously to children every day as a rich source of vitamins A and D. It was also used to treat children with rickets, a bone disease due to vitamin D deficiency.
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Collagen: Collagen is the principal protein of the skin, tendons, cartilage, bone and connective tissue.

Colon: The part of the large intestine that runs from the cecum to the rectum as a long hollow tube that serves to remove water from digested food and let the remaining material, solid waste called stool , move through it to the rectum and leave the body through the anus . .
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Coma: A state of deep unarousable unconsciousness.
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Common cold: A viral upper respiratory tract infection. This contagious illness can be caused by many different types of viruses , and the body can never build up resistance to all of them. For this reason, colds are a frequent and recurring problem. In fact kindergarten children average 12 colds per year, while adolescents and adults have around seven colds per year.
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Condition: The term "condition" has a number of biomedical meanings including the following:

1. An unhealthy state, such as in "this is a progressive condition."
2. A state of fitness, such as "getting into condition."
3. Something that is essential to the occurrence of something else; essentially a "precondition."
4. As a verb: to cause a change in something so that a response that was previously associated with a certain stimulus becomes associated with another stimulus; to condition a person, as in behavioral conditioning.

Constipation: Infrequent (and frequently incomplete) bowel movements. The opposite of diarrhea, constipation is commonly caused by irritable bowel syndrome, diverticulosis, and medications (constipation can paradoxically be caused by overuse of laxatives). Colon cancer can narrow the colon and thereby cause constipation. The large bowel (colon) can be visualized by barium enema x-rays, sigmoidoscopy, and colonoscopy. Barring a condition such as cancer, high-fiber diets can frequently relieve the constipation.

Corneal: Pertaining to the cornea, the clear front window of the eye that transmits and focuses light into the eye.

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.
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Cysteine: An amino acid, one of the 20 building blocks of protein. Cysteine can be synthesized by the body and is not essential to the diet. Its key chemical feature is a thiol group that contains sulfur. This thiol group can combine with the thiol group of another cysteine to form a disulfide bridge, which helps structural proteins and enzymes maintain their configuration. Two cysteine molecules linked by a disulfide bridge make up the amino acid cystine. The symbol for cysteine is Cys.

Cystic fibrosis : One of the most common grave genetic (inherited) diseases, CF affects the exocrine glands and is characterized by the production of abnormal secretions, leading to mucous build-up.
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Dementia : Significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning.
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Dentin: Dentin is the hard tissue of the tooth surrounding the central core of nerves and blood vessels (pulp).

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.
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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).
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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.
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Disease: Illness or sickness often characterized by typical patient problems (symptoms) and physical findings (signs). Disruption sequence: The events that occur when a fetus that is developing normally is subjected to a destructive agent such as the rubella (German measles) virus.

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.)
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Dopamine: An important neurotransmitter (messenger) in the brain.
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Dry skin: Abnormally dry skin . Can be caused by a dry climate, winter weather, deficiency of vitamin A , systemic illness, overexposure to sunlight, or medication . The skin loses moisture. It may crack and peel. Or it may become irritated, inflamed, and itch . Bathing frequently, especially with soaps, can contribute to dry skin.
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Egg: Ovum (plural: ova).

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.
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Enzymes: Proteins that act as a catalysts in mediating and speeding a specific chemical reaction .
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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."

Estrogen: Estrogen is a female hormone produced by the ovaries. Estrogen deficiency can lead to osteoporosis .
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Familial: A condition that is tends to occur more often in family members than expected by chance alone. A familial disease may be genetic (such as cystic fibrosis ) or environmental (such as tuberculosis ).
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Familial hypercholesterolemia: The most common inherited type of hyperlipidemia (high lipid levels in blood). One in every 500 children is born with familial hypercholesterolemia. The condition predisposes to premature arteriosclerosis including coronary artery disease with heart attacks at an unusually young age.
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Family: 1. A group of individuals related by blood or marriage or by a feeling of closeness. 2. A biological classification of related plants or animals that is a division below the order and above the genus. 3. A group of genes related in structure and in function that descended from an ancestral gene. 4. A group of gene products similarly related in structure and function and of shared genetic descent. 5. Parents and their children. The most fundamental social group in humans.

Fat: 1 Along with proteins and carbohydrates, one of the three nutrients used as energy sources by the body. The energy produced by fats is 9 calories per gram. Proteins and carbohydrates each provide 4 calories per gram. 2 Total fat; the sum of saturated, monounsaturated and polyunsaturated fats. Intake of monounsaturated and polyunsaturated fats can help reduce blood cholesterol when substituted for saturated fats in the diet. 3 A slang term for obese or adipose. 4 In chemistry, a compound formed from chemicals called fatty acids. These fats are greasy, solid materials found in animal tissues and in some plants. Fats are the major component of the flabby material of a body, commonly known as blubber.

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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Fats: Plural of the word "fat". See the definition of fat.

Fiber : The parts of plants that cannot be digested, namely complex carbohydrates. Also known as bulk or roughage.
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Folate: Folic acid, one of the B vitamins that is a key factor in the synthesis (the making) of nucleic acid (DNA and RNA).
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Folic acid: One of the B vitamins that is a key factor in the synthesis (the making) of nucleic acid (DNA and RNA).
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Fracture: A break in bone or cartilage. Although usually the result of trauma, a fracture can be caused by an acquired disease of bone such as osteoporosis or by abnormal formation of bone in a disease such as osteogenesis imperfecta ("brittle bone disease"). Fractures are classified according to their character and location as, for example, a greenstick fracture of the radius.
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Gastritis: Inflammation of the stomach. From the Latin gastricus meaning stomach + -itis, meaning inflammation.

Genes: The basic biological units of heredity . Segments of deoxyribonucleic acid (DNA) needed to contribute to a function.
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Genetic: Having to do with genes and genetic information.

Germ: 1. A cell or group of cells (called a primordium ) capable of developing into an organ , a part or an organism in its entirety. Eggs and sperm are germ cells .

2. A pathogenic a microorganism. A microbe capable of causing disease . The germ theory of disease held, correctly, that these minute bodies can cause disease.

3. The figurative source or wellspring. Dr. Watson told Holmes he had the germ of an idea.
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Glucose: The simple sugar (monosaccharide) that serves as the chief source of energy in the body. Glucose is the principal sugar the body makes. The body makes glucose from proteins, fats and, in largest part, carbohydrates. Glucose is carried to each cell through the bloodstream. Cells, however, cannot use glucose without the help of insulin . Glucose is also known as dextrose.
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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.
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HDL: High density lipoprotein.
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HDL cholesterol: Lipoproteins, which are combinations of lipids (fats) and proteins, are the form in which lipids are transported in the blood. The high-density lipoproteins transport cholesterol from the tissues of the body to the liver so it can be gotten rid of (in the bile). HDL cholesterol is therefore considered the "good" cholesterol. The higher the HDL cholesterol level, the lower the risk of coronary artery disease.
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Headache : A pain in the head with the pain being above the eyes or the ears, behind the head (occipital), or in the back of the upper neck. Headache, like chest pain or back ache, has many causes.
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Health: As officially defined by the World Health Organization, a state of complete physical, mental, and social well-being, not merely the absence of disease or infirmity.

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 attack: The death of heart muscle due to the loss of blood supply. The loss of blood supply is usually caused by a complete blockage of a coronary artery, one of the arteries that supplies blood to the heart muscle. Death of the heart muscle, in turn, causes chest pain and electrical instability of the heart muscle tissue.
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Heart disease: Any disorder that affects the heart. Sometimes the term "heart disease" is used narrowly and incorrectly as a synonym for coronary artery disease. Heart disease is synonymous with cardiac disease but not with cardiovascular disease which is any disease of the heart or blood vessels. Among the many types of heart disease, see, for example: Angina; Arrhythmia; Congenital heart disease; Coronary artery disease (CAD); Dilated cardiomyopathy; Heart attack (myocardial infarction); Heart failure; Hypertrophic cardiomyopathy; Mitral regurgitation; Mitral valve prolapse; and Pulmonary stenosis.

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.
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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 .
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Hemolytic: Referring to hemolysis, the destruction of red blood cells which leads to the release of hemoglobin from within the red blood cells into the blood plasma .
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Hemolytic anemia: Anemia due to the destruction (rather than underproduction) of red blood cells.

Hemorrhage: Bleeding or the abnormal flow of blood.
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High blood pressure : Also known as hypertension, high blood pressure is, by definition, a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140 with a diastolic pressure above 90.
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Homocysteine : An amino acid produced by the body, usually as a byproduct of consuming meat. Homocysteine is made from another amino acid, methionine, and then in turn is converted into other amino acids.
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Hypercholesterolemia: High blood cholesterol. This can be sporadic (with no family history) or familial.
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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.

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.
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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.
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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 .
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Institute of Medicine: One of the National Academies of the United States. The Institute of Medicine conducts policy studies on health issues.
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Intestine: The long, tubelike organ in the abdomen that completes the process of digestion. It consists of the small and large intestines.

Intrinsic: 1. An essential or inherent part of a something such as a structure.
2. Coming from within, from the inside. Proteins have intrinsic signals that govern their transport and localization in the cell.
From the Latin intrinsecus meaning situated on the inside. The opposite of intrinsic is extrinsic.

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.

Iron deficiency anemia : The most common known form of nutritional disorder in the world, iron deficiency results in anemia because iron is necessary to make hemoglobin, key molecule in red blood cells responsible for the transport of oxygen. In iron deficiency anemia, the red cells appear abnormal and are unusually small (microcytic) and pale (hypochromic). The pallor of the red cells reflects their low hemoglobin content.
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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.

LDL cholesterol: Lipoproteins which are combinations of lipids (fats) and proteins are the form in which lipids are transported in the blood. The low-density lipoproteins transport cholesterol from the liver to the tissues of the body. LDL cholesterol is therefore considered the "bad" cholesterol.

Linus Pauling: See: Pauling, Linus.

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.

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.
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Marrow: The bone marrow.

Medication: 1. A drug or medicine. 2. The administration of a drug or medicine. (Note that "medication" does not have the dangerous double meaning of "drug.")

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.
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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.
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Metabolism: The whole range of biochemical processes that occur within us (or any living organism). Metabolism consists both of anabolism and catabolism (the buildup and breakdown of substances, respectively). The term is commonly used to refer specifically to the breakdown of food and its transformation into energy.

Methionine: An amino acid, one of the 20 building blocks of protein. A dietary essential amino acid, methionine provides methyl groups and sulfur for normal metabolism. Symbol: Met.

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.

National Academy of Sciences: One of the National Academies. Created in 1863 by a congressional charter approved by President Abraham Lincoln at the height of the Civil War.

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.

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.

Neural: Having to do with nerve cells.
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Neurological: Having to do with the nerves or the nervous system.

Neuropathy: Any and all disease or malfunction of the nerves.

New England Journal of Medicine: Despite its regional name, The New England Journal of Medicine (NEJM) is far from provincial. It is an eminent weekly national and international general medical journal, devoted to no single specialty, but to all of medicine. The Journal is published by the Massachusetts Medical Society and is closely associated with the medical schools (Boston University, Harvard and Tufts) in the Boston area.
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Niacin: Nicotinic acid, one of the B-complex B vitamins. Deficiency of niacin in the diet results in the disease pellagra. See: Pellagra.

Nose: The external midline projection from the face.
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Nursing: 1) Profession concerned with the provision of services essential to the maintenance and restoration of health by attending the needs of sick persons. 2) Feeding a infant at the breast.

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.
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Olive: In neuroanatomy, a rounded oval prominence on the surface of the medulla oblongata in the brain. There are two olives, corresponding to the two olivary bodies, one on each side of the medulla oblongata. Nerve fibers in the olivopontocerebellar pathway connect the olives to the pons and cerebellum .
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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.
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Organic: 1. A chemical compound that contains carbon.
2. Related to an organ.
3. Grown or prepared without the use of chemicals or pesticides, as in organic food.
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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.
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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.
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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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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 .

Pancreatitis : Inflammation of the pancreas. Of the many diverse causes of pancreatitis , the most common are alcohol and gallstones .

Parkinsonism: 1. Parkinson disease.
2. A syndrome similar to Parkinson disease, for example, as a side effect of an antipsychotic drug.

Pauling: See: Pauling, Linus

Pellagra: A disease due to deficiency of niacin, a B-complex vitamin. Pellagra is the "disease of the four D's" --

• Diarrhea;
• Dermatitis: A scaly rash on skin exposed to light or trauma;
• Dementia: Mental disorientation, delusions and depression ; and
• Death.

Peripheral: Situated away from the center, as opposed to centrally located.
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Peripheral neuropathy : A problem with the functioning of the nerves outside the spinal cord. Symptoms may include numbness, weakness, burning pain (especially at night), and loss of reflexes.
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Pernicious anemia : A blood disorder caused by inadequate vitamin B12 in the blood. Patients who have this disorder do not produce the substance in the stomach that allows the body to absorb vitamin B12. This substance is called intrinsic factor (IF).
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Pill: In pharmacy, a medicinal substance in a small round or oval mass meant to be swallowed. Pills often contain a filler and a plastic substance such as lactose that permits the pill to be rolled by hand or machine into the desired form. The pill may then be coated with a varnishlike substance.
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Placebo: A "sugar pill" or any dummy medication or treatment.
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Placebo-controlled: A term used to describe a method of research in which an inactive substance (a placebo) is given to one group of participants, while the treatment (usually a drug or vaccine) being tested is given to another group. The results obtained in the two groups are then compared to see if the investigational treatment is more effective than the placebo.

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.

Postmenopausal: After the menopause . Postmenopausal is defined formally as the time after which a woman has experienced twelve (12) consecutive months of amenorrhea (lack of menstruation) without a period.
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Precursor: Forerunner. That which precedes or is derived from an available source.
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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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Progressive: Increasing in scope or severity. Advancing. Going forward. In medicine, a disease that is progressive is going from bad to worse.
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Prospective: Looking forward. A prospective study or a prospective clinical trial is one in which the participants are identified and then followed forward in time.
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Prostate: A gland within the male reproductive system that is located just below the bladder. Chestnut shaped, the prostate surrounds the beginning of the urethra, the canal that empties the bladder.
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Prostate cancer: An uncontrolled (malignant) growth of cells in the prostate gland which is located at the base of the urinary bladder and is responsible for helping control urination as well as forming part of the semen. Prostate cancer is the second leading cause of death of males in the U.S.

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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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.
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Psoriasis : A reddish, scaly rash often located over the surfaces of the elbows, knees, scalp, and around or in the ears, navel, genitals or buttocks. Psoriasis is an autoimmune disease that is mediated by T lymphocytes. It is also a very common disease, Chronic plaque psoriasis affects approximately 2% of people around the world. About 10-15% of patients with psoriasis develop joint inflammation (inflammatory arthritis ). Treatment options include topical steroid creams, tar soap preparations, and exposure to ultraviolet light.
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Pyridoxine: One of the vitamin B6 group (which also includes pyridoxal and pyridoxamine) that is transformed in the body to pyridoxal phosphate, which functions as a coenzyme, a substance that enhances the action of an enzyme and thereby helps catalyze and speed a biochemical reaction. (A number of vitamins serve as coenzymes.)
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Randomized: The use of chance alone to assign the participants in an experiment or trial to different groups in order to fairly compare the outcomes with different treatments. Randomization is an important feature of experimental design.
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RDA: Abbreviation for the Recommended Dietary Allowance. Or, popularly, the Recommended Daily Allowance.

Recommended Daily Allowance: Popular name for the Recommended Dietary Allowance (RDA).

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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Resection: Surgical removal of part of an organ.

Respiratory: Having to do with respiration, the exchange of oxygen and carbon dioxide. From the Latin re- (again) + spirare (to breathe) = to breathe again.

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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Retinol: Retinol is vitamin A. 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. Deficiency of vitamin A leads to night blindness.
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Rickets: A disease of infants and children that disturbs normal bone formation (ossification). Rickets is a failure to mineralize bone. This softens bone (producing osteomalacia) and permits marked bending and distortion of bones. Up through the first third of the 20th century, rickets was largely due to lack of direct exposure to sunlight or lack of vitamin D. Sunlight provides the necessary ultraviolet rays. These rays do not pass through ordinary window glass. Once the role of vitamin D in rickets was discovered, cod liver oil (which is rich in vitamin D) became a favored, if not too tasty, remedy. Thanks to such supplements of vitamin D, nutritional rickets has become relatively rare in industrialized nations. It still occurs, for example, in breast-fed babies whose mothers are underexposed to sunlight and in dark-skinned babies who are not given vitamin D supplements. And in unindustrialized countries, vitamin D deficiency rickets continues to be a problem. Rickets in North America and Europe now is usually not nutritional.
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RNA: Short for ribonucleic acid, a nucleic acid molecule similar to DNA but containing ribose rather than deoxyribose. RNA is formed upon a DNA template. There are several classes of RNA molecules.
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Scurvy: A disorder caused by lack of vitamin C. Symptoms include anemia; soft, bleeding gums; and bumps under the skin near muscles. Scurvy in early childhood can cause musculoskeletal problems. Treatment is by including foods high in vitamin C in the diet, and by vitamin C supplements if needed. See also: Paprika.

Seizure: Uncontrolled electrical activity in the brain, which may produce a physical convulsion, minor physical signs, thought disturbances, or a combination of symptoms.
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Seizure disorders: One of a great many medical conditions that are characterized by episodes of uncontrolled electrical activity in the brain (seizures). Some seizure disorders are hereditary, but others are caused by birth defects or environmental hazards, such as lead poisoning. Seizure disorders are more likely to develop in patients who have other neurological disorders, psychiatric conditions, or immune-system problems. In some cases, uncontrolled seizures can cause brain damage, lowered intelligence, and permanent mental and physical impairment. Diagnosis is by observation, neurological examination, electroencephalogram (EEG), and in some cases more advanced brain imaging techniques. Treatment is usually by medication, although in difficult cases a special diet or brain surgery may be tried.
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Sensory: Relating to sensation , to the perception of a stimulus and the voyage made by incoming ( afferent ) nerve impulses from the sense organs to the nerve centers.
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Serotonin: A hormone , also called 5-hydroxytryptamine , in the pineal gland , blood platelets, the digestive tract, and the brain. Serotonin acts both as a chemical messenger that transmits nerve signals between nerve cells and that causes blood vessels to narrow.
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Side effects: Problems that occur when treatment goes beyond the desired effect. Or problems that occur in addition to the desired therapeutic effect.
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Skin: The skin is the body's outer covering. It protects us against heat and light, injury, and infection. It regulates body temperature and stores water, fat, and vitamin D. Weighing about 6 pounds, the skin is the body's largest organ. It is made up of two main layers; the outer epidermis and the inner dermis.

Small bowel: Another name for the small intestine .
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Small intestine: The part of the digestive tract that extends from the stomach to the large intestine.

Sore: 1. (adjective) A popular term for painful. I have sore fingers from typing dictionary terms. She has a sore throat . 2. (noun) A nondescript term for nearly any lesion of the skin or mucous membranes. He has a number of sores in his mouth.

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Spina bifida: A birth defect (a congenital malformation ) in which there is a bony defect in the vertebral column so that part of the spinal cord, which is normally protected within the vertebral column, is exposed. People with spina bifida can suffer from bladder and bowel incontinence , cognitive (learning) problems and limited mobility.
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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.
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Stomach cancer : Cancer of the stomach , the main organ that holds food for digestion. Worldwide, stomach cancer is the second most frequent cancer and the second leading cause of death from cancer. It can develop in any part of the stomach and spread to other organs. It is also known as gastric cancer.
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Sunscreen: A substance that blocks the effect of the sun's harmful rays. Using lotions that contain sunscreens can reduce the risk of skin cancer, including melanoma.

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.
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Synthesis: Putting together different entities to make a whole which is new and different. In biochemistry , synthesis refers specifically to the process of building compounds from more elementary substances by means of one or more chemical reactions.
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Therapy: The treatment of disease .
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Thiamine: Vitamin B1. Thiamine (vitamin B1) acts as a coenzyme in the metabolism of the body. Deficiency of thiamine leads to beriberi, a syndrome characterized by inflammation of multiple nerves (polyneuritis), heart disease (cardiopathy), and edema (swelling).
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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 .
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Tongue: The tongue is a strong muscle anchored to the floor of the mouth. It is covered by the lingual membrane which has special areas to detect tastes.
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Tooth: The structures within the mouth that allow for biting and chewing. Teeth have different shapes, depending on their purpose. The sharp canine and frontal teeth allow for biting, while the flattened, thick molars in the back of the mouth provide grinding surfaces for masticating food. All teeth have essentially the same structure: a hard crown above the gum line, which is attached to two or four roots by a portion called the neck. The roots are covered with a very thin layer of bone, and keep the tooth embedded in the bones of the jaw. The exposed exterior of the tooth is covered with tough enamel. Under the enamel is a thick layer of dentin, and in the center is the pulp. Blood vessels and nerves are found within the pulp.
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Toxicity: The degree to which a substance can harm humans or animals.
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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.
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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.

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.

Vessel: A tube in the body that carries fluids: blood vessels or lymph vessels.

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.
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Vitamin A deficiency: A lack of vitamin A.
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Vitamin B12: A vitamin important for the normal formation of red blood cells and the health of the nerve tissues. Undetected and untreated vitamin B12 deficiency can lead to anemia and permanent nerve and brain damage.
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Vitamin C: An essential nutrient found mainly in fruits and vegetables. The body requires vitamin C to form and maintain bones, blood vessels, and skin.
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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.
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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 .
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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.
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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.
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Warfarin : An anticoagulant drug (brand names: Coumarin, Panwarfin, Sofarin) taken to prevent the blood from clotting and to treat blood clots and overly thick blood. Warfarin is also used to reduce the risk of clots causing strokes or heart attacks .
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Xerophthalmia: Dry eyes. Xerophthalmia can be associated with systemic diseases such as Sjögren' s syndrome, systemic lupus erythematosus , rheumatoid arthritis , scleroderma , sarcoidosis , amyloidosis , and hypothyroidism ; deficiency of vitamin A; and the use of some medications including antihistamines, nasal decongestants, tranquilizers, and anti-depressant drugs. Xerophthalmia results from inadequate function of the lacrimal glands which produce tears. When xerophthalmia is due to vitamin A deficiency, the condition begins with night blindness and conjunctival xerosis (dryness of the eye membranes) and progresses to corneal xerosis (dryness of the cornea), and, in the late stages, to keratomalacia (softening of the cornea).
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From the Doctors at MedicineNet.com

Electroretinography - Read about electroretinography (ERG), an eye test where electrodes placed on the cornea measure electrical responses to light to try to detect abnormal retinal function. Source:MedicineNet Taking Dental Medications - Learn what questions to ask the dentist before taking dental medications. Be sure to tell your dentist if you're pregnant, taking other drugs, have drug allergies or medical conditions. Source:WebMD Medical Reference from The Cleveland Clinic Pernicious Anemia - Read about a blood disorder called pernicious anemia caused when the body does not make enough red blood cells due to lack of vitamin B12. Symptoms, diagnosis, treatment, and prevention information is included. Source:Government Read 321 more Vitamins and Calcium Supplements related articles ... Garlic & Vitamin Pill for Heart Disease? Glucosamine: No Help for Hip Arthritis? Folic Acid Doesn't Help the Heart Grapefruit Compound Inhibits Hepatitis C Virus Low Vitamin D Tied to Depression in Older Adults Vitamin D Deficiency Worsens Breast Cancer? Omega-3 Fatty Acids Won't Prevent Crohn's Relapse Health Tip: Potassium-Rich Foods Low Vitamin D Levels May Boost Men's Heart Attack Risk Cancer Patients Should Steer Clear of Antioxidants