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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 ...

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...

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. ...

vertigo

(Encyclopedia)vertigo vûrˈtĭgō [key], sensations of moving in space or of objects moving about a person and the resultant difficulty in maintaining equilibrium. True vertigo, as distinguished from faintness, li...

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...

conjunctivitis

(Encyclopedia)conjunctivitis kənjəngtəvīˈtəs [key], inflammation or infection of the mucosal membrane that covers the eyeball and lines the eyelid, usually acute, caused by a virus or, less often, by a bacill...

Cushing, Harvey Williams

(Encyclopedia)Cushing, Harvey Williams, 1869–1939, American neurosurgeon, b. Cleveland, B.A. Yale, 1891, M.D. Harvard, 1895. Associated with Johns Hopkins (1896–1912), Harvard (1912–32), and Yale (1933–37),...

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