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acetylcholine

(Encyclopedia)acetylcholine əsētˌəlkōˈlēn [key], a small organic molecule liberated at nerve endings as a neurotransmitter. It is particularly important in the stimulation of muscle tissue. The transmission ...

Nurse, Sir Paul Maxime

(Encyclopedia)Nurse, Sir Paul Maxime, 1949–, British biochemist, Ph.D. Univ. of East Anglia, 1973. Nurse was associated with the Imperial Cancer Research Fund (now Cancer Research UK London Research Institute) fo...

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...

lactic acid

(Encyclopedia)lactic acid, CH3CHOHCO2H, a colorless liquid organic acid. It is miscible with water or ethanol. Lactic acid is a fermentation product of lactose (milk sugar); it is present in sour milk, koumiss, leb...

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...

Pap test

(Encyclopedia)Pap test, Pap smear, or Papanicolaou test păpˌənēˈkəlou [key], medical procedure used to detect cancer of the uterine cervix (see uterus). A scraping, brushing, or smear, is taken from the surf...

blue baby

(Encyclopedia)blue baby, infant born with a congenital heart defect that causes a bluish coloration of the skin as a result of cyanosis (deoxygenated blood). The color is most noticeable around the lips and at the ...

tamoxifen

(Encyclopedia)tamoxifen təmŏkˈsĭfĕnˌ [key], synthetic hormone used in the treatment of breast cancer. Introduced in 1978, tamoxifen is used to prevent recurrences of cancer in women who have already undergone...

tonsils

(Encyclopedia)tonsils, name commonly referring to the palatine tonsils, two ovoid masses of lymphoid tissue situated on either side of the throat at the back of the tongue. The pharyngeal tonsils, or adenoids, are ...

optical character recognition

(Encyclopedia)optical character recognition (OCR), method for the machine-reading of typeset, typed, and, in some cases, hand-printed letters, numbers, and symbols using optical sensing and a computer. The light re...