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calcium-channel blocker

(Encyclopedia)calcium-channel blocker, any of a class of drugs used in treating hypertension, angina pectoris, and certain arrhythmias. They prevent the calcium ions needed for muscle contraction from entering the ...

Benedek, Ludwig von

(Encyclopedia)Benedek, Ludwig von lo͞otˈvĭkh fən bāˈnədĕkˌ [key], 1804–81, Austrian general. Entering the army in 1822, he served in the suppression of the Polish insurrection of 1846, in the Austrian ca...

wart

(Encyclopedia)wart, circumscribed outgrowth of the skin caused by a filterable virus that is readily transmitted. Warts may appear anywhere on the skin but are most common on the hands. Sexually transmitted disease...

West, Jerry

(Encyclopedia)West, Jerry (Jerome Alan West), 1938–, American basketball player, b. Cheylan, W.Va. One of the game's great shooting guards, he led West Virginia Univ. to the 1959 National Collegiate Athletic Asso...

lighthouse

(Encyclopedia)lighthouse, towerlike structure erected to give guidance and warning to ships and aircraft by either visible or radioelectrical means. Lighthouses were long built to conform in structure to their geog...

hygrometer

(Encyclopedia)hygrometer hīgrŏmˈətər [key], instrument used to measure the moisture content of a gas, as in determining the relative humidity of air. The temperature at which dew or frost forms is a measure of...

chemical equation

(Encyclopedia)chemical equation, group of symbols representing a chemical reaction. There are a number of other symbols used in chemical equations. A symbol written above or below the reaction arrow indicates spe...

magnetic levitation

(Encyclopedia)magnetic levitation or maglev măgˈlĕv [key], support and often propulsion of objects or vehicles by the use of magnets. The magnets used in magnetic levitation suspend an object free of contact wit...

bubble chamber

(Encyclopedia)bubble chamber, device for detecting charged particles and other radiation by means of tracks of bubbles left in a chamber filled with liquid hydrogen or other liquefied gas. It was invented in 1952 b...

metamorphism

(Encyclopedia)metamorphism, in geology, process of change in the structure, texture, or composition of rocks caused by agents of heat, deforming pressure, shearing stress, hot, chemically active fluids, or a combin...