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(la-mel'a) plural.lamellae [L., a little plate]
1. A thin layer, sheet, or plate.
2. A medicated disk of gelatin inserted under the lower eyelid and against the eyeball; used as a local application to the eye.

bone lamella

Plates of collagen fibers, 3 to 7 µm thick, found in secondary (mature, adult) bone and surrounded by cementing substance, the mineralized bone matrix. Some lamellae are parallel to each other. Other lamellae are aligned concentrically around a vascular canal — a structure known as a haversian system or osteon.

circumferential lamella

A layer of bone that underlies the periosteum, encircling the medullary cavity.

concentric lamella

One of the cylindrical plates of bone surrounding a haversian canal. Synonym: haversian l

enamel lamella

Microscopic cracks or calcification imperfections in the enamel surface of a tooth. They may be shallow or extend into the underlying dentin and occur as a developmental defect or a microfracture caused by temperature change or shearing forces.

ground lamella

Interstitial lamella.

haversian lamella

Concentric lamella.

interstitial lamella

The bone lamella filling the irregular spaces within the haversian system. Synonym: ground l.

medullary lamella

An osseous lamella surrounding and forming the wall of the marrow cavity of long bones.

periosteal lamella

The bone lamella next to and parallel with the periosteum, forming the external portion of bone.

triangular lamella

The small fibrous lamina between the choroid plexuses of the third ventricle of the brain.

vitreous lamella

Bruch's membrane.
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
However, no peak is observed on the SAXS profiles during this period indicating that the crystalline entities formed are not in interaction or, in other words, are dispersed and isolated into the amorphous matrix (formation of isolated crystalline lamellae).
Among alterations observed there was an increase in blood cell volume in secondary lamellae (secondary lamellar dilation), characterizing aneurisms along with smaller and free pillar cells that normally should adhere to pavement cells to form a channel (Fig.
Several authors found that thickness of the lamellae measured in the eye bank preoperatively and post-operatively did not correspond.
Secondary lamellae from infected fish showed a strong increase in secretory cells, which was appreciably higher at the distal end of the primary lamellae (stained blue or purple) containing neutral and acids mucopolysaccharides.
WI) 7700 tool was used to artificially grind off lamellae on randomly selected lamellose N.
Diagnosis: Basidiomata clitocyboid, pileus 13-30 mm diam., infundibuliform to plano-convex, white to pastel grey, lamellae decurrent, stipe cylindrical, with mycelial pad and rhizomorphs, basidiospores 4-5 x 3-4.3 [mu]m, globose to subglobose, smooth to slightly angled in polar view, cystidia absent, pileipellis a transition between trichocutis and a trichoderm, clamp connection absent.
In this study, the gills Labeo rohita showed degenerative, necrotic, proliferative changes in gill filaments and secondary lamellae, and congestion in the blood vessels of gill filaments.
Gill anomalies of fish exposed to BPA included hyperplasia, fusion, clubbing and uplifting of secondary lamellae and degeneration of primary lamellae.
It is reported as a synonym of "Elongate sclerite" quoting Matthews (1974), who actually used the term in its most undefined sense ("flagellum or spicule"), in order to indicate some sclerotized structures, who really are accessory lamellae. The copulatory spicule was described by Zunino (1972) as "spicola copulatrice" for the genus Euonthophagus Balthasar.
The ExSolve WTP system is an automated, high-throughput sample preparation system that can prepare site-specific, 20nm thick lamellae on whole wafers up to 300mm in diameter.
This creates layers or lamellae that operate as a tunable Bragg reflector.