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gonadotropic hormone

(Encyclopedia)gonadotropic hormone gōˌnădətrŏpˈĭk [key] or gonadotropin, any one of three glycoprotein (see protein) hormones released by either the anterior pituitary gland or the placenta (the organ in whi...

macaque

(Encyclopedia)macaque məkäkˈ [key], name for Old World monkeys of the genus Macaca, related to mangabeys, mandrills, and baboons. All but one of the 19 species are found in Asia from Afghanistan to Japan, the Ph...

mental retardation

(Encyclopedia)mental retardation, below average level of intellectual functioning, usually defined by an IQ of below 70 to 75, combined with limitations in the skills necessary for daily living. Daily living skills...

Periodic Table of the Elements: Rhodium

(Encyclopedia)Periodic Table of the Elements: Rhodium ...

Cohen, Stanley

(Encyclopedia)Cohen, Stanley, 1922–2020, American biochemist, b. New York City, Ph.D. Univ. of Michigan, 1948. Cohen did his most important work at Washington Univ. with Rita Levi-Montalcini in the 1950s. Studyin...

Cook, Ebenezer

(Encyclopedia)Cook, Ebenezer, fl. 1708, American author. Virtually nothing is known about his life. He is the author of The Sot-Weed Factor (1708), a satirical poem concerning an Englishman's visit to Maryland. Sot...

distortion

(Encyclopedia)distortion, in electronics, undesired change in an electric signal waveform as it passes from the input to the output of some system or device. In an audio system, distortion results in poor reproduct...

Levi-Montalcini, Rita

(Encyclopedia)Levi-Montalcini, Rita lāˈvē-mŏnˌtəlsēˈnē [key], 1909–2012, Italian-American neurologist, b. Turin, Italy, M.D. Univ. of Turin, 1936. A dual citizen of Italy and the United States, Levi-Mont...

Trans-Amazon Highway

(Encyclopedia)Trans-Amazon Highway, road, c.3,000 mi (4,830 km) long, traversing N central Brazil. The highway, stretching from the Atlantic coast to the Peruvian border, is an important factor in the economic deve...

hemolysis

(Encyclopedia)hemolysis hĭmŏlˈĭsĭs [key], destruction of red blood cells in the bloodstream. Although new red blood cells, or erythrocytes, are continuously created and old ones destroyed, an excessive rate of...