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sympathomimetic drug

(Encyclopedia)sympathomimetic drug sĭmpăthˌōmĭmĕtˈĭk [key], any of a group of substances whose actions resemble the response of stimulated sympathetic nerves (see nervous system). These drugs include epinep...

phallic worship

(Encyclopedia)phallic worship fălˈĭk [key], worship of the reproductive powers of nature as symbolized by the male generative organ. Phallic symbols have been found by archaeological expeditions all over the wor...

cartilage

(Encyclopedia)cartilage kärˈtəlĭj [key], flexible semiopaque connective tissue without blood vessels or nerve cells. It forms part of the skeletal system in humans and in other vertebrates, and is also known as...

adrenocorticotropic hormone

(Encyclopedia)adrenocorticotropic hormone ədrēˈnōkôrˌtəkōtrŏpˈĭk [key], polypeptide hormone secreted by the anterior pituitary gland. Its chief function is to stimulate the cortex of the adrenal gland to...

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...

meninges

(Encyclopedia)CE5 Meninges: Section of spine showing meningeal layers meninges mĭnĭnˈjēz [key], three membranous layers of connective tissue that envelop the brain and spinal cord (see nervous system). The ...

leishmaniasis

(Encyclopedia)leishmaniasis lēshˌmənīˈəsĭs [key], any of a group of tropical diseases caused by parasitic protozoans of the genus Leishmania. The parasites live in dogs, foxes, rodents, and humans; they are ...

Pavlov, Ivan Petrovich

(Encyclopedia)Pavlov, Ivan Petrovich ēvänˈ pētrôˈvĭch pävˈləf [key], 1849–1936, Russian physiologist and experimental psychologist. He was professor at the military medical academy and director of the p...

gland

(Encyclopedia)gland, organ that manufactures chemical substances. A gland may vary from a single cell to a complex system of tubes that unite and open onto a surface through a duct. The endocrine glands, e.g., the ...

glucagon

(Encyclopedia)glucagon glo͞oˈkəgŏn [key], hormone secreted by the α cells of the islets of Langerhans, specific groups of cells in the pancreas. It tends to counteract the action of insulin, i.e., it raises th...