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parathyroid hormone

(Encyclopedia)parathyroid hormone or parathormone, a hormone secreted by the parathyroid glands that regulates the metabolism of calcium and phosphate in the body. It has been purified extensively and appears to be...

adhesive

(Encyclopedia)adhesive, substance capable of sticking to surfaces of other substances and bonding them to one another. The term adhesive cement is sometimes used in place of adhesive, especially when referring to a...

Wolfe, Tom

(Encyclopedia)Wolfe, Tom (Thomas Kennerly Wolfe, Jr.), 1931–2018, American journalist and novelist, b. Richmond, Va., B.A. Washington and Lee Univ., 1951, Ph.D. Yale, 1957. He began his writing career as a newspa...

caffeine

(Encyclopedia)caffeine kăfēnˈ [key], odorless, slightly bitter alkaloid found in coffee, tea, kola nuts (see cola), ilex plants (the source of the Latin American drink maté), and, in small amounts, in cocoa (se...

Adonis, Syrian poet

(Encyclopedia)Adonis or Adunis, pen name of Ali Ahmad Said Esber, 1930–, Syrian poet and essayist, generally considered the Arab world's greatest living poet. He began writing poetry in the 1950s. After being jai...

black fly

(Encyclopedia)black fly, name for any of the flies of the family Simuliidae. The black fly is about 1⁄8 in. (3.2 mm) long and has large eyes, short legs, a stout, humped back, broad gauzy wings, and piercing-suck...

stethoscope

(Encyclopedia)stethoscope stĕthˈəskōpˌ [key] [Gr.,=chest viewer], instrument that enables the physican to hear the sounds made by the heart, the lungs, and various other organs. The earliest stethoscope, devis...

vendetta

(Encyclopedia)vendetta vĕndĕtˈə [key] [Ital.,=vengeance], feud between members of two kinship groups to avenge a wrong done to a relative. Although the term originated in Corsica, the custom has also been pract...

bedbug

(Encyclopedia)bedbug, any of the small, blood-sucking bugs of the family Cimicidae, which includes about 30 species distributed throughout the world. Bedbugs are flat-bodied, oval, reddish brown, and about 1⁄4 in...

thyrotropin

(Encyclopedia)thyrotropin thīˌrätrōˈpĭn [key] or thyroid-stimulating hormone (TSH), hormone released by the anterior pituitary gland that stimulates the thyroid gland to release thyroxine. The release of thyr...