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neoplasm

(Encyclopedia)neoplasm or tumor, tissue composed of cells that grow in an abnormal way. Normal tissue is growth-limited, i.e., cell reproduction is equal to cell death. Feedback controls limit cell division after a...

corticosteroid drug

(Encyclopedia)corticosteroid drug kôrˌtəkōstârˈoid [key], any one of several synthetic or naturally occurring substances with the general chemical structure of steroids. They are used therapeutically to mimic...

cystic fibrosis

(Encyclopedia)cystic fibrosis sĭsˈtĭk fībrōˈsĭs [key], inherited disorder of the exocrine glands (see gland), affecting children and young people; median survival is 25 years in females and 30 years in males...

epinephrine

(Encyclopedia)epinephrine ĕpˌənĕfˈrīn [key], hormone important to the body's metabolism, also known as adrenaline. Epinephrine, a catecholamine, together with norepinephrine, is secreted principally by the me...

iodine

(Encyclopedia)iodine īˈədīn, –dĭn [key] [Gr.,=violet], nonmetallic chemical element; symbol I; at. no. 53; at. wt. 126.90447; m.p. 113.5℃; b.p. 184.35℃; sp. gr. 4.93 at 20℃; valence −1, +1, +3, +5, o...

vasectomy

(Encyclopedia)vasectomy, male sterilization by surgical excision of the vas deferens, the thin duct that carries sperm cells from the testicles to the prostate and the penis. Vasectomy is a popular method of birth ...

corticosterone

(Encyclopedia)corticosterone kôrˌtəkōstĕrˈōn [key], steroid hormone secreted by the outer layer, or cortex, of the adrenal gland. Classed as a glucocorticoid, corticosterone helps regulate the conversion of ...

hypothalamus

(Encyclopedia)hypothalamus hīˌpəthălˈəməs [key], an important supervisory center in the brain, rich in ganglia, nerve fibers, and synaptic connections. It is composed of several sections called nuclei, each ...

boil

(Encyclopedia)boil or furuncle fyo͝orˈŭngkəl [key], tender, painful inflammatory nodule in the skin, which becomes pustular but with a hard center (see abscess). It may be caused by any of various microbes, the...

testis

(Encyclopedia)testis tĕsˈtĭkəl [key], one of a pair of glands that produce the male reproductive cells, or sperm. In fetal life the testes develop in the abdomen, then descend into an external sac, the scrotum....