islet


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Related to islet: islet cells

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.

is·let

(ī'let),
A small island.

islet

/is·let/ (-lit) an island.
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.

islet

[ī′lət]
Etymology: MFr, islette, little island
a cluster of cells or an isolated piece of tissue. Also called island.

is·let

(ī'lĕt)
A small island.

islet

an island.

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).
References in classic literature ?
Then he remembered in a flash what the Burgomaster gull had screamed to him when he was a little yearling at Walrus Islet, and he tumbled backward in the water, for he knew that he had found Sea Cow at last.
He sat long enough for the declining sun to dip behind the roofs of the town at his back, and throw the shadow of the houses on the lake front over the islet, before he pulled out of his pocket a fountain pen, opened a small notebook on his knee, and began to write quickly, raising his eyes now and then at the connecting arm of the bridge.
I thought it was going to pass it by, when, going back to north-west, it went through a large quantity of islands and islets little known, towards the Island Sound and Canal Mauvais.
At the place now mentioned it might measure about ninety miles in breadth, and at its southern extremity the captain found a group of islets, which he named the Archipelago of Bengal.
The precise point of destination was still undecided--the plan being to search out a suitable location upon one of the many little islets which dot the western shore of the Macassar Strait.
He did not know that this Meringe Lagoon, backed by high, forested mountains and fronted and sheltered by the off- shore coral islets, was anything else than the entire world.
The scent of the spice islands was in his nostrils as he had known it on warm, breathless nights at sea, or he beat up against the southeast trades through long tropic days, sinking palm-tufted coral islets in the turquoise sea behind and lifting palm-tufted coral islets in the turquoise sea ahead.
Below some small masses of guano at Ascension, and on the Abrolhos Islets, I found certain stalactitic branching bodies, formed apparently in the same manner as the thin white coating on these rocks.
His sisters had seen the family danger, and had never forgotten to discount the gold islets that raised them from the sea.
The rocky islets lay on the sea like the heaps of a cyclopean ruin on a plain; the centipedes and scorpions lurked un der the stones; there was not a single blade of grass in sight anywhere, not a single lizard sunning him self on a boulder by the shore.
A strange name wakes up memories; the printed words scent the smoky atmosphere of to-day faintly, with the subtle and penetrating perfume as of land breezes breathing through the starlight of bygone nights; a signal fire gleams like a jewel on the high brow of a sombre cliff; great trees, the advanced sentries of immense forests, stand watchful and still over sleeping stretches of open water; a line of white surf thunders on an empty beach, the shallow water foams on the reefs; and green islets scattered through the calm of noonday lie upon the level of a polished sea, like a handful of emeralds on a buckler of steel.
1846; The Red Skins, 1846; The Crater (Marks Reef), 1847; Captain Spike, or the Islets of the Gulf, 1848; Jack Tier, or the Florida Reefs, 1848; The Oak Openings, or the Bee-Hunter, 1848; The Sea Lions,