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Rift Valley fever

(Encyclopedia)Rift Valley fever, acute viral disease that affects domestic livestock and can be transmitted to humans. The disease is most common in E and S Africa, but also occurs widely in sub-Saharan Africa and ...

cobalt, chemical element

(Encyclopedia)cobalt, metallic chemical element; symbol Co; at. no. 27; at. wt. 58.9332; m.p. 1,495℃; b.p. about 2,870℃; sp. gr. 8.9 at 20℃; valence +2 or +3. Cobalt is a silver-white, lustrous, hard, brittle...

cerebral palsy

(Encyclopedia)cerebral palsy sərēˈbrəl pôlˈzē [key], disability caused by brain damage before or during birth or in the first years, resulting in a loss of voluntary muscular control and coordination. Althou...

estrogen

(Encyclopedia)CE5 estrogen ĕsˈtrəjən [key], any one of a group of hormones synthesized by the reproductive organs and adrenal glands in females and, in lesser quantities, in males. The estrogens cause the th...

nicotine

(Encyclopedia)nicotine, C10H14N2, poisonous, pale yellow, oily liquid alkaloid with a pungent odor and an acrid taste. It turns brown on exposure to air. Nicotine, a naturally occurring constituent of tobacco, is t...

osteoporosis

(Encyclopedia)osteoporosis ŏsˌtēōˌpərōˈsĭs [key], disorder in which the normal replenishment of old bone tissue is severely disrupted, resulting in weakened bones and increased risk of fracture; osteopenia...

cortisone

(Encyclopedia)cortisone kôrˈtĭsōnˌ [key], steroid hormone whose main physiological effect is on carbohydrate metabolism. It is synthesized from cholesterol in the outer layer, or cortex, of the adrenal gland u...

cystic fibrosis

(Encyclopedia)cystic fibrosis sĭsˈtĭk fībrōˈsĭs [key], inherited disorder of the exocrine glands (see gland), affecting children and young people; median survival is 25 years in females and 30 years in males...

hemophilia

(Encyclopedia)hemophilia hēˌməfĭlˈēə, –fēlˈyə [key], genetic disease in which the clotting ability of the blood is impaired and excessive bleeding results. The disease is transmitted through females but...

arteriosclerosis

(Encyclopedia)arteriosclerosis ärtĭrˌēōsklərōˈsis [key], general term for a condition characterized by thickening, hardening, and loss of elasticity of the walls of the blood vessels. These changes are freq...