steroids definition of steroids in the Free Online Encyclopedia.

steroids, class of lipids lipids, a broad class of organic products found in living systems. Most are insoluble in water but soluble in nonpolar solvents. The definition excludes the mineral oils and other petroleum products obtained from fossil material.
..... Click the link for more information. having a particular molecular ring structure called the cyclopentanoperhydro-phenanthrene ring system. Steroids differ from one another in the structure of various side chains and additional rings. Steroids are common in both plants and animals. In humans, steroids are secreted by the ovaries and testes, the adrenal cortex (see adrenal gland adrenal gland (ədrēn`əl) or suprarenal gland
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The range of steroids is diverse, including several forms of vitamin D, digitalis, sterols (e.g., cholesterol cholesterol (kəlĕs`tərōl')
..... Click the link for more information. ), and the bile acids. Many steroids are biologically active hormones hormone, secretory substance carried from one gland or organ of the body via the bloodstream to more or less specific tissues, where it exerts some influence upon the metabolism of the target tissue.
..... Click the link for more information. that control a number of the body's metabolic processes. This group includes the male sex hormone testosterone testosterone (tĕstŏs`tərōn), principal androgen, or male sex hormone .
..... Click the link for more information. and the female sex hormones estrogen estrogen (ĕs`trəjən)
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..... Click the link for more information. . The steroid hormones of the adrenal cortex include glucocorticoids such as cortisone cortisone (kôr`tĭsōn'), steroid hormone whose main physiological effect is on carbohydrate metabolism.
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..... Click the link for more information. ) and mineralocorticoids such as aldosterone aldosterone (ăl'dōstĭrōn`), steroid secreted by the cortex of the adrenal gland.
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Natural or synthetic steroids are used in oral contraceptives and in the treatment of arthritis arthritis, painful inflammation of a joint or joints of the body, usually producing heat and redness. There are many kinds of arthritis. In its various forms, arthritis disables more people than any other chronic disorder.
..... Click the link for more information. , Addison's disease Addison's disease [for Thomas Addison ], progressive disease brought about by atrophy of the outer layer, or cortex, of the adrenal gland ; it is also called chronic adrenocortical insufficiency.
..... Click the link for more information. , and certain skin ailments. Side effects, related to dosage and length of treatment, can be serious and include high blood pressure, edema, unwanted hair growth, and menstrual cycle disruption. Anabolic steroids anabolic steroid (ăn'əbŏl`ĭk stĕr`oid, stĭr`–) or androgenic steroid
..... Click the link for more information. , male hormones given to build up strength in seriously ill patients, have been abused by bodybuilders and athletes in an attempt to increase muscle mass and strength.