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carotene

(Encyclopedia)carotene kârˈətēnˌ [key], long-chained, unsaturated hydrocarbon found as a pigment in many higher plants, particularly carrots, sweet potatoes, and leafy vegetables. Carotene is thought to assist...

tamoxifen

(Encyclopedia)tamoxifen təmŏkˈsĭfĕnˌ [key], synthetic hormone used in the treatment of breast cancer. Introduced in 1978, tamoxifen is used to prevent recurrences of cancer in women who have already undergone...

tonsils

(Encyclopedia)tonsils, name commonly referring to the palatine tonsils, two ovoid masses of lymphoid tissue situated on either side of the throat at the back of the tongue. The pharyngeal tonsils, or adenoids, are ...

bighorn, in zoology

(Encyclopedia)bighorn or Rocky Mountain sheep, wild sheep, Ovis canadensis, of W North America, formerly plentiful in mountains from SW Canada to N Mexico. Indiscriminate hunting, disease, and scarcity of food enor...

reserpine

(Encyclopedia)reserpine rĕsûrˈpēn [key], alkaloid isolated from the root of the snakeroot plant (Rauwolfia serpentina), a small evergreen climbing shrub of the dogbane family native to the Indian subcontinent. ...

meningitis

(Encyclopedia)meningitis sĕrˌəbrōspīˈnəl [key], acute inflammation of the meninges, the membranes that cover and protect the brain and spinal cord. It can be caused by bacteria, viruses, fungi, or other orga...

e-commerce

(Encyclopedia)e-commerce, commerce conducted over the Internet, most often via the World Wide Web. E-commerce can apply to purchases made through the Web or to business-to-business activities such as inventory tran...

corticosteroid drug

(Encyclopedia)corticosteroid drug kôrˌtəkōstârˈoid [key], any one of several synthetic or naturally occurring substances with the general chemical structure of steroids. They are used therapeutically to mimic...

genetic testing

(Encyclopedia)genetic testing, medical screening for genetic disorders, by examining either a person's DNA directly or a person's biochemistry or chromosomes for indirect evidence. Testing may be done to identify a...

Dugdale, Richard Louis

(Encyclopedia)Dugdale, Richard Louis dŭgˈdāl [key], 1841–83, American social investigator, b. Paris. While inspecting (1874) county jails for the New York Prison Association, he developed data for his famous s...