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serotonin

(Encyclopedia)serotonin sĕrˌətōˈnĭn [key], organic compound that was first recognized as a powerful vasoconstrictor occurring in blood serum. It was partially purified, crystallized, and named in 1948, and it...

probiotic

(Encyclopedia)probiotic, live microorganism administered to a host with the intention of providing a health benefit, or a food, supplement, or treatment containing such microorganisms. Many of the microbes found in...

criminology

(Encyclopedia)criminology, the study of crime, society's response to it, and its prevention, including examination of the environmental, hereditary, or psychological causes of crime, modes of criminal investigation...

duck

(Encyclopedia)duck, common name for wild and domestic waterfowl of the family Anatidae, which also includes geese and swans. It is hunted and bred for its meat, eggs, and feathers. Strictly speaking, duck refers to...

autism

(Encyclopedia)autism ôˈtĭzəm [key], developmental disability resulting from a neurological disorder that affects the normal functioning of the brain. It is characterized by the abnormal development of communica...

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...

Ottocar II

(Encyclopedia)Ottocar II or Přemysl Ottocar II, c.1230–1278, king of Bohemia (1253–78), son and successor of Wenceslaus I. Ottocar shrewdly exploited the disorders of the great interregnum in the Holy Roman Em...

pneumonia

(Encyclopedia)pneumonia no͝omōnˈyə [key], acute infection of one or both lungs that can be caused by a bacterium, usually Streptococcus pneumoniae (also called pneumococcus; see streptococcus), or by a virus, f...

blindness

(Encyclopedia)blindness, partial or complete loss of sight. Blindness may be caused by injury, by lesions of the brain or optic nerve, by disease of the cornea or retina, by pathological changes originating in syst...

biotechnology

(Encyclopedia)biotechnology, the use of biological processes, as through the exploitation and manipulation of living organisms or biological systems, in the development or manufacture of a product or in the technol...