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oxytocin

(Encyclopedia)oxytocin ŏksĭtōˈsĭn [key], hormone released from the posterior lobe of the pituitary gland that facilitates uterine contractions and the milk-ejection reflex. The structure of oxytocin, a cyclic ...

hydrogen peroxide

(Encyclopedia)hydrogen peroxide, chemical compound, H2O2, a colorless, syrupy liquid that is a strong oxidizing agent and, in water solution, a weak acid. It is miscible with cold water and is soluble in alcohol an...

Edelman, Gerald Maurice

(Encyclopedia)Edelman, Gerald Maurice, 1929–2014, American biochemist and neuroscientist, b. Queens, N.Y., M.D. Univ. of Pennsylvania, 1954; Ph.D. Rockefeller Institute, 1960. He was a professor at the Rockefelle...

Grignard reagent

(Encyclopedia)Grignard reagent grēnyärdˈ rēāˈjənt [key], any of an important class of extremely reactive chemical compounds used in the synthesis of hydrocarbons, alcohols, carboxylic acids, and other compou...

heartburn

(Encyclopedia)heartburn, burning sensation beneath the breastbone, also called pyrosis. Heartburn does not indicate heart malfunction but results from nervous tension or overindulgence in food or drink. The sensati...

keratin

(Encyclopedia)keratin kĕrˈətĭn [key], any one of a class of fibrous protein molecules that serve as structural units for various living tissues. The keratins are the major protein components of hair, wool, nail...

phospholipid

(Encyclopedia)phospholipid fŏsˌfōlĭpˈĭd [key], lipid that in its simplest form is composed of glycerol bonded to two fatty acids and a phosphate group. The resulting compound called phosphatidic acid contains...

borax

(Encyclopedia)borax or sodium tetraborate decahydrate sōˈdēəm tĕˌtrəbôrˈāt dĕkˌəhīˈdrāt [key], chemical compound, Na2B4O7·10H2O; sp. gr. 1.73; slightly soluble in cold water; very soluble in hot wa...

phenol

(Encyclopedia)phenol fēˈnōl [key], C6H5OH, a colorless, crystalline solid that melts at about 41℃, boils at 182℃, and is soluble in ethanol and ether and somewhat soluble in water. An aromatic alcohol, it ex...

hydrogen

(Encyclopedia)hydrogen hīˈdrəjən [key] [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; interval in which at. wt. ranges 1.00784–1.00811; m.p. −259.14℃; b.p. −252.87℃; density 0.08...