Columbia Encyclopedia

Search results

127 results found

amenorrhea

(Encyclopedia)amenorrhea āmĕnˌərēˈa, əmĕnˌ– [key], cessation of menstruation. Primary amenorrhea is a delay in or a failure to start menstruation; secondary amenorrhea is an unexpected stop to the menstr...

Schally, Andrew V.

(Encyclopedia)Schally, Andrew V., 1926–, American endocrinologist, b. Wilno, Poland (now Vilnius, Lithuania), as Andrzej Viktor Schally, grad. McGill Univ. (Ph.D., 1957). He spent most of his career at Tulane Uni...

pseudocyesis

(Encyclopedia)pseudocyesis so͞oˌdōsīēˈsĭs [key], imaginary pregnancy in women usually resulting from a strong desire or need for motherhood. In the absence of conception, the menstrual periods nevertheless c...

growth hormone

(Encyclopedia)growth hormone or somatotropin sōmătˌətrōˈpən [key], glycoprotein hormone released by the anterior pituitary gland that is necessary for normal skeletal growth in humans (see protein). Evidence...

ovary

(Encyclopedia)ovary, ductless gland of the female in which the ova (female reproductive cells) are produced. In vertebrate animals the ovary also secretes the sex hormones estrogen and progesterone, which control t...

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 ...

puberty

(Encyclopedia)puberty pyo͞oˈbərtē [key], period during which the onset of sexual maturity occurs. It usually takes place between the ages of 10 and 15 in both sexes but sometimes occurs as early as 7 or 8 years...

hormone

(Encyclopedia)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. ...

adolescence

(Encyclopedia)adolescence, time of life from onset of puberty to full adulthood. The exact period of adolescence, which varies from person to person, falls approximately between the ages 12 and 20 and encompasses b...