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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...

transplantation, medical

(Encyclopedia)transplantation, medical, surgical procedure by which a tissue or organ is removed and replaced by a corresponding part, usually from another part of the body or from another individual. A life-saving...

Mollusca

(Encyclopedia)Mollusca məlŭsˈkə [key], taxonomic name for the one of the largest phyla of invertebrate animals (Arthropoda is the largest) comprising more than 50,000 living mollusk species and about 35,000 fos...

chloramphenicol

(Encyclopedia)chloramphenicol klōrˌămfĕnˈəkŏlˌ [key], antibiotic effective against a wide range of gram-negative and gram-positive bacteria (see Gram's stain). It was originally isolated from a species of S...

ergot

(Encyclopedia)ergot ûrˈgət [key], disease of rye and other cereals caused by the fungus Claviceps purpurea. The cottony, matlike body, or mycelium, of the fungus develops in the ovaries of the host plant; it eve...

Ignarro, Louis Joseph

(Encyclopedia)Ignarro, Louis Joseph, 1941–. American pharmacologist, b. Brooklyn, N.Y., Ph.D. Univ. of Minnesota, 1966. He was on the faculty at Tulane Univ. from 1979 to 1985, when he became a professor at the U...