islet

islet /is·let/ (-lit) an island.

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islets of Langerhans  irregular microscopic structures scattered throughout the pancreas and comprising its endocrine portion. They contain the alpha cells, which secrete the hyperglycemic factor glucagon; the beta cells, which secrete insulin; the delta cells, which secrete somatostatin; and the PP (or F ) cells, which secrete pancreatic polypeptide. Degeneration of the beta cells is one of the causes of diabetes mellitus.

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is·let (lt)

n.

A small island.

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islet

[ī′lət]

Etymology: MFr, islette, little island

a cluster of cells or an isolated piece of tissue. Also called island.

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islet [i´let]

an island.

i's of Langerhans (pancreatic i's) irregular microscopic structures scattered throughout the pancreas and comprising its endocrine portion. They contain the alpha cells, which secrete the hyperglycemic factor glucagon; the beta cells, which secrete insulin, and whose degeneration is one of the causes of diabetes mellitus; and the delta cells, which secrete somatostatin.

Walthard's i's microscopic inclusions of the ovarian germinal epithelium, which have been implicated in the development of Brenner tumors.

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islet

an island.

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islet cell

one of the cells making up the islet of Langerhans.

islet cell neoplasia

occur mostly in old dogs and morphologically they occur as adenomas or adenocarcinomas. Functionally they appear only in the form of hyperinsulinism and hypoglycemia. Rarely there are gastrin-secreting tumors causing a zollinger-ellison syndrome.

i's of Langerhans

irregular microscopic structures scattered throughout the pancreas and comprising its endocrine portion. They contain the alpha cells, which secrete the hyperglycemic factor glucagon; the beta cells, which secrete insulin, and whose degeneration is one of the causes of diabetes mellitus; and the delta cells, which secrete somatostatin.

pancreatic islet

see islets of Langerhans (above).