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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...

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 ...

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 ...

Kawasaki disease

(Encyclopedia)Kawasaki disease or Kawasaki syndrome, acute illness characterized by inflammation of the blood vessels that primarily affects young children; it is more common in boys and children of Asian descent. ...

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...

James, Saint (the “brother” of Jesus)

(Encyclopedia)James, Saint, in the Bible, the “brother” of Jesus. The Gospels make several references to the brothers of Jesus, and St. Paul speaks of “James the Lord's brother.” While Protestants generally...

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...

trichina

(Encyclopedia)trichina trĭkīˈnə [key], common name for species of roundworm of the phylum Nematoda. The species Trichinella spiralis is an important parasite, occurring in rats, pigs, and man, and is responsibl...

menstruation

(Encyclopedia)menstruation, periodic flow of blood and cells from the lining of the uterus in humans and most other primates, occurring about every 28 days in women. Menstruation commences at puberty (usually betwe...