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progesterone

(Encyclopedia)progesterone prōjĕsˈtərōnˌ [key], female sex hormone that induces secretory changes in the lining of the uterus essential for successful implantation of a fertilized egg. A steroid, progesterone...

Axelrod, Julius

(Encyclopedia)Axelrod, Julius ăkˈsəlrŏd [key], 1912–2004, American biochemist whose work was influential in the development of pharmaceuticals, b. New York City, grad. City College, N.Y. (B.S. 1933), New York...

honey badger

(Encyclopedia)honey badger or ratel rātˈəl [key], carnivore, Mellivora capensis, of the forest and brush country of Africa, the Middle East, and India; it is a member of the badger and skunk family. Related to t...

eye

(Encyclopedia)CE5 Cross section of human eye eye, organ of vision and light perception. In humans the eye is of the camera type, with an iris diaphragm and variable focusing, or accommodation. Other types of ey...

autoimmune disease

(Encyclopedia)autoimmune disease, any of a number of abnormal conditions caused when the body produces antibodies to its own substances. In rheumatoid arthritis, a group of antibody molecules called collectively RF...

seasonal affective disorder

(Encyclopedia)seasonal affective disorder (SAD), recurrent fall or winter depression characterized by excessive sleeping, social withdrawal, depression, overeating, and pronounced weight gain. SAD effects an estima...

chromosome

(Encyclopedia)chromosome krōˈməsōmˌ [key], structural carrier of hereditary characteristics, found in the nucleus of every cell and so named for its readiness to absorb dyes. The term chromosome is usually res...

cystitis

(Encyclopedia)cystitis sĭstīˈtĭs [key], common acute or chronic inflammation of the urinary bladder. The disease occurs primarily in young women and frequently results from bacterial invasion of the urethra fro...

radioactive isotope

(Encyclopedia)radioactive isotope or radioisotope, natural or artificially created isotope of a chemical element having an unstable nucleus that decays, emitting alpha, beta, or gamma rays until stability is reache...

hoopoe

(Encyclopedia)hoopoe ho͞oˈpo͞o, –pō [key], common name for a shy, solitary, Old World woodland bird, Upupa epops. Its body color ranges from cinnamon to chestnut, with white-barred, black wings and tail, and ...