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Vane, Sir John Robert

(Encyclopedia)Vane, Sir John Robert, 1927–2004, British pharmacologist, Ph.D. Oxford, 1953. With B. I. Samuelsson and Sune K. Bergström, Vane was awarded the 1982 Nobel Prize in Physiology or Medicine. The trio ...

Semenza, Gregg Leonard

(Encyclopedia)Semenza, Gregg Leonard, 1956–, American oncologist and molecular biologist, b. New York City, Ph.D. Univ. of Pennsylvania, 1984. Semenza has spent his entire career at the Johns Hopkins School of Me...

placenta

(Encyclopedia)placenta pləsĕnˈtə [key] or afterbirth, organ that develops in the uterus during pregnancy. It is a unique characteristic of the higher (or placental) mammals. In humans it is a thick mass, about ...

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. ...

prostaglandin

(Encyclopedia)prostaglandin prŏsˌtəglănˈdən [key], any of a group of about a dozen compounds synthesized from fatty acids in mammals as well as in lower animals. Prostaglandins are highly potent substances th...

pregnancy

(Encyclopedia)pregnancy, period of time between fertilization of the ovum (conception) and birth, during which mammals carry their developing young in the uterus (see embryo). The average duration of pregnancy in h...

drug poisoning

(Encyclopedia)drug poisoning, toxic effects caused by an administered drug. Worldwide more than 9 million natural and synthetic chemicals have been identified; fewer than 3000 cause more than 95% of acidental and d...

endocytosis

(Encyclopedia)endocytosis ĕnˌdōsītōˈsəs [key], in biology, process by which substances are taken into the cell. When the cell membrane comes into contact with a suitable food, a portion of the cell cytoplasm...

fluke

(Encyclopedia)fluke, parasitic flatworm of the trematoda class, related to the tapeworm. Instead of the cilia, external sense organs, and epidermis of the free-living flatworms, adult flukes have sucking disks with...

stimulant

(Encyclopedia)stimulant, any substance that causes an increase in activity in various parts of the nervous system or directly increases muscle activity. Cerebral, or psychic, stimulants act on the central nervous s...