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heart, in anatomy

(Encyclopedia)CE5 Cross section of heart, with arrows indicating direction of blood flow heart, muscular organ that pumps blood to all parts of the body. The rhythmic beating of the heart is a ceaseless activit...

Furies

(Encyclopedia)Furies or Erinyes ērĭnˈē-ēz [key], in Greek and Roman religion and mythology, three daughters of Mother Earth, conceived from the blood of Uranus, when Kronos castrated him. They were powerful di...

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 ...

anticoagulant

(Encyclopedia)anticoagulant ănˌtēkōăgˈyələnt [key], any of several substances that inhibit blood clot formation (see blood clotting). Some anticoagulants, such as the coumarin derivatives bishydroxycoumarin...

aorta

(Encyclopedia)CE5 Aorta aorta āôrˈtə [key], primary artery of the circulatory system in mammals, delivering oxygenated blood to all other arteries except those of the lungs. The human aorta, c.1 in. (2.54 c...

pulse, in anatomy

(Encyclopedia)pulse, alternate expansion and contraction of artery walls as heart action varies blood volume within the arteries. Artery walls are elastic. Hence they become distended by increased blood volume duri...

hypertension

(Encyclopedia)hypertension or high blood pressure, elevated blood pressure resulting from an increase in the amount of blood pumped by the heart or from increased resistance to the flow of blood through the small a...

histology

(Encyclopedia)histology hĭstŏlˈəjē [key], study of the groups of specialized cells called tissues that are found in most multicellular plants and animals. Histologists study the organization of tissues at all ...

Huston, John

(Encyclopedia)Huston, John hyo͞osˈtən [key], 1906–87, American motion picture director, writer, and actor, b. Nevada, Mo. In many of his films, such as The Treasure of the Sierra Madre (1948) and Moby Dick (19...

stimulant

(Encyclopedia)stimulant, any substance that causes an increase in activity in various parts of the nervous system or directly increases muscle activity. Cerebral, or psychic, stimulants act on the central nervous s...