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calcium

(Encyclopedia)calcium kălˈsēəm [key] [Lat.,=lime], metallic chemical element; symbol Ca; at. no. 20; at. wt. 40.078; m.p. about 839℃; b.p. 1,484℃; sp. gr. 1.55 at 20℃; valence +2. Calcium is a malleable, ...

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...

bleaching powder

(Encyclopedia)bleaching powder, white or nearly white powder that is usually a mixture of calcium chloride hypochlorite, CaCl(OCl); calcium hypochlorite, Ca(OCl)2; and calcium chloride, CaCl2. Sometimes called chlo...

calcium oxide

(Encyclopedia)calcium oxide, chemical compound, CaO, a colorless, cubic crystalline or white amorphous substance. It is also called lime, quicklime, or caustic lime, but commercial lime often contains impurities, e...

parathyroid glands

(Encyclopedia)parathyroid glands pârˌəthīˈroid [key], four small endocrine bodies, located behind the thyroid gland, that govern calcium and phosphorus metabolism. These four masses of tissue (each about the s...

calcium hydroxide

(Encyclopedia)calcium hydroxide, Ca(OH)2, colorless crystal or white powder. It is prepared by reacting calcium oxide (lime) with water, a process called slaking, and is also known as hydrated lime or slaked lime. ...

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 ...

Ca

(Encyclopedia)Ca, symbol for the element calcium. ...

lime-sulfur

(Encyclopedia)lime-sulfur, mixture of calcium polysulfides formed by reacting (e.g., by boiling) calcium hydroxide (slaked lime) with sulfur. It is used as an insecticide and fungicide. ...

tetany

(Encyclopedia)tetany tĕtˈənē [key], condition of mineral imbalance in the body that results in severe muscle spasms. Tetany occurs when the concentration of calcium ions (Ca++) in extracellular fluids such as p...
 

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