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colchicine

(Encyclopedia)colchicine kŏlˈchəsēnˌ [key], alkaloid extracted from plants of the genus Colchicum and especially from the corms of the autumn crocus, Colchicum autumnale (see meadow saffron). The metabolic eff...

antisense

(Encyclopedia)antisense, DNA or RNA manipulated in a laboratory so that its components (nucleotides) form a complementary copy of normal, or “sense,” messenger RNA (mRNA; see nucleic acid). Antisense techniques...

acetaldehyde

(Encyclopedia)acetaldehyde ĕthˈənălˌ [key], CH3CHO, colorless liquid aldehyde, sometimes simply called aldehyde. It melts at −123℃, boils at 20.8℃, and is soluble in water and ethanol. It is formed by th...

phosgene

(Encyclopedia)phosgene fŏsˈjēn [key], colorless poison gas, first used during World War I by the Germans (1915). When dispersed in air, the gas has the odor of new-mowed hay. The gas is highly toxic; when inhale...

printed circuit

(Encyclopedia)printed circuit, electric circuit in which the conducting paths connecting circuit components are affixed to a flat, insulating base board. The base is typically of plastic, glass, ceramic, or some ot...

Trail

(Encyclopedia)Trail, city (1991 pop. 7,919), SE British Columbia, Canada, on the Columbia River just N of the Wash. border. It is a metal-smelting center for a mining area that produces lead, zinc, silver, and gold...

ribosome

(Encyclopedia)ribosome: see cell; nucleic acid. ...

aqua fortis

(Encyclopedia)aqua fortis äkˈwə fôrˈtĭs [key]: see nitric acid. ...

methyl salicylate

(Encyclopedia)methyl salicylate səlĭsˈəlātˌ [key], methyl ester of salicylic acid. ...

Heiberg, Johan Ludvig

(Encyclopedia)Heiberg, Johan Ludvig yōhănˈ lo͞oᵺˈvē hīˈbâr [key], 1791–1860, Danish writer, director of the National Theater. In the play Christmas Fun and New Year's Jesting (1817), he satirized leadi...