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pyrimidine

(Encyclopedia)CE5 Pyrimidines found in deoxyribonucleic acid (DNA) pyrimidine pīrĭmˈĭdēnˌ [key], type of organic base found in certain coenzymes and in the nucleic acids of plant and animal tissue. The th...

emetic

(Encyclopedia)emetic əmĕtˈĭk [key], substance that produces vomiting. Direct, or gastric, emetics, which act directly on the stomach, include syrup of ipecac, sulfate of zinc or copper, alum, ammonium carbonate...

column

(Encyclopedia)column, vertical architectural support, circular or polygonal in plan. A column is generally at least four or five times as high as its diameter or width; stubbier freestanding masses of masonry are u...

aliphatic compound

(Encyclopedia)aliphatic compound ălˌəfătˈĭk [key], any of a large class of organic compounds whose carbon atoms are joined together in straight or branched open chains rather than in rings. The hydrocarbons o...

methotrexate

(Encyclopedia)methotrexate, drug used in halting the growth of actively proliferating tissues. Introduced in the 1950s, it is used in the treatment of leukemia, psoriasis, and non-Hodgkin's lymphoma. By binding to ...

Lindahl, Tomas

(Encyclopedia)Lindahl, Tomas, 1938–, Swedish-born British biochemist, grad. Karolinska Institute (Ph.D. 1967, M.D. 1970). Lindahl was a professor at the Univ. of Gothenburg from 1978 to 1982. In 1981 he joined th...

Khorana, Har Gobind

(Encyclopedia)Khorana, Har Gobind, 1922–2011, American biochemist, b. Raipur (now in Pakistan), Ph.D. Univ. of Liverpool, 1948. He became a U.S. citizen in 1966, and was a professor at the Massachusetts Institute...

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...

nitrocellulose

(Encyclopedia)nitrocellulose, nitric acid ester of cellulose (a glucose polymer). It is usually formed by the action of a mixture of nitric and sulfuric acids on purified cotton or wood pulp. The extent of nitratio...

silage

(Encyclopedia)silage ĕnˈsəlĭj [key], succulent, moist feed made by storing a green crop in a silo. The crop most used for silage is corn; others are sorghum, sunflowers, legumes, and grass. In a sealed silo, ty...