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Related to keratinous: keratinous cyst


1. Any of a class of filamentous proteins that are abundant in the cytoskeleton of vertebrate epithelial cells and are the main constituents of the outer layer of skin and tough epidermal structures such as hair, nails, hooves, feathers, and claws.
2. Material composed principally of keratin proteins.

[Greek keras, kerāt-, horn; see ker- in Indo-European roots + -in.]

ke·rat′i·nous (kə-răt′n-əs) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biology) horny or made of keratin
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


a. queratinosa-a, rel. a o de la naturaleza de la queratina.
English-Spanish Medical Dictionary © Farlex 2012
References in periodicals archive ?
The influence of hydration on the tensile and compressive properties of avian keratinous tissues.
The ear canal was acutely inflamed and filled with keratinous debris, findings that are consistent with otitis externa.
Trichofolliculomas show squamous epithelium lined cystic cavity within dermis enclosing keratinous material and hair shafts with numerous small secondary hair follicles emanating from the cyst wall.
Occasional keratinous cysts and a matrix of varying composition can also be found.7
Aspirates of lymphoepithelial cyst reveal squamous cells, keratinous materials, lymphocytes, histiocytes, and cholesterol crystals.
Permanent sections were reported as "acellular keratinous debris" (figure 2, B).
The lesion was excised from base and specimen was sent for HPE, which showed only keratinous accumulation in epidermis, no specific pathology was found.
PC is a rare, autosomal dominant disorder characterized by triad of subungual hyperkeratosis with accumulation of hard keratinous material beneath the distal portion of the nails, lifting the nails from the nail bed, keratosis palmaris et plantaris with thick callosities, especially on the soles and thick white areas on the oral mucosa.4,5 Other associated features which may occur include keratosis pilaris, hyperkeratotic follicular papules on the sites of friction, hair abnormalities and hyperhidrosis of the palms and soles.
(4,6) Small, keratinous cysts are present around the skin surface.
(5) The rupture of a cholesteatoma sac and the spillage of keratinous substance into the subepithelial layer usually causes a marked granulomatous reaction of a foreign-body type, but it is not associated with cholesterol crystals and hemosiderin-laden macrophages.