American Medical Association Family Medical Guide - American Medical Association [803]
antigens Proteins such as microorganisms or toxins that trigger the immune system to produce antibodies to fight them.
antioxidants Molecules that protect against cell damage caused by free radicals.
apheresis Also called pheresis. A procedure in which blood is removed, run through a machine that removes selected components such as platelets, white blood cells, or stem cells, and then reinfused into the person. The removed blood components are stored and later used in blood transfusions or stem cell transplants.
apnea Involuntary cessation of breathing that may be intermittent and temporary, or prolonged.
apnea, sleep Intermittent, temporary cessation of breathing during sleep. The condition often occurs in people who are overweight.
arrhythmia An abnormally fast or slow heartbeat or an irregular heartbeat. The two main types of arrhythmias are bradycardia and tachycardia.
artery A blood vessel that carries oxygen-filled blood away from the heart to the organs and tissues.
arthritis See osteoarthritis.
arthroplasty Also called joint replacement. A surgical procedure in which a damaged joint is replaced with an artificial joint made of metal and plastic. Arthroplasty is performed most often on the knee and hip, but is also used on the ankles, hands, wrists, and toes.
artificial respiration See artificial ventilation.
artificial ventilation Also called artificial respiration or assisted breathing. Introduction of air—either with mouth-to-mouth resuscitation or with a machine called a ventilator—into the lungs of a person who has stopped breathing.
aspiration A procedure in which fluid or tissue is removed from a body cavity with an instrument such as a needle and syringe. Aspiration also refers to accidentally inhaling an object or substance, such as food.
asymptomatic Without signs or symptoms of disease. Two conditions that are often asymptomatic, especially in the early stages, are high blood pressure and type 2 diabetes.
atheroma See plaque, arterial.
atherosclerosis The buildup of hardened fatty deposits called arterial plaque inside artery walls. Atherosclerosis can narrow the blood vessels, reducing or blocking blood flow to organs and tissues and increasing the risk of heart attack or stroke.
atrophy Shrinking or wasting of an organ or tissue as a result of disease or lack of use.
autoimmune disease A disease in which the immune system mistakenly produces antibodies that attack the body’s own cells and tissues. Rheumatoid arthritis is one type of autoimmune disease.
autologous blood donation Donation of a person’s own blood before scheduled elective surgery to ensure that the blood is available if a transfusion is necessary during or after surgery.
autologous bone marrow transplant See bone marrow transplant.
autologous stem cell transplant See stem cell transplant.
autopsy Also called a postmortem. The examination of a body after death to determine the cause of death. An autopsy is performed if death seems to have occurred under suspicious circumstances or if the family of the deceased requests it, or to provide information for research or medical education.
B
bacteremia A life-threatening condition in which bacteria are present in the bloodstream.
bacteria Single-celled microorganisms that multiply by division. Bacteria are classified according to their shape, such as cocci (round) or bacilli (rod-shaped or cylinder-shaped).
bacteriuria The presence of bacteria in urine.
basal cell carcinoma A slow-growing form of skin cancer in the outer layer of skin that rarely spreads to other parts of the body. Basal cell carcinoma accounts for about 90 percent of all skin cancers.
B cell Also called B lymphocyte. A type of white blood cell that has an important role in the immune system, protecting the body from infections and cancer.
benign Not cancerous.
beta carotene An antioxidant found in orange and deep-yellow fruits and vegetables that converts to vitamin A in the body.
bile A greenish yellow fluid produced by the liver, stored in the gallbladder,