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Relating to an operculum.
Farlex Partner Medical Dictionary © Farlex 2012


Relating to an operculum.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


(ō-pĕr′kū-lŭm) plural.opercula [L., a cover]
1. Any lid or covering.
2. The narrow opening at the top of the thoracic cage bordered by the sternum and first ribs.
3. The plug of mucus that fills the opening of the cervix on impregnation.
4. The convolutions of the cerebrum, the margins of which are separated by the lateral cerebral (sylvian) fissure. The opercula cover the insula. opercular (ō-pĕr′kū-lăr), adjective

dental operculum

The soft tissue overlying the crown of a partially erupted tooth.

trophoblastic operculum

The plug of fibrin that covers the opening in the endometrium made by implantation of the blastocyst.
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
However Acrostichum and Ceratopteris showed different features: 1) Acrostichum is typically found in brackish or saline habits near coasts, true halophyte or semi-halophyte, while Ceratopteris inhabits fresh or occasionally brackish wetlands and rarely in terrestrial situations on poorly drained soils worldwide of tropics and subtropics (Dettmann & Clifford, 1991); 2) Spores in Acrostichum and Ceratopteris are trilete, tetrahedral-globose to nearly globose, but they differ in ornamentation, 3) Antheridia in Acrostichum have an asymmetric opercular cell whereas Ceratopteris showed undivided cap cell.
Pomatostegus stellatus has scattered simple ocelli appearing on the radioles (type S) as well as on the opercular brim (type oS).
Opercular abnormalities may be caused by genetic factors, as usually seen in Miller-Dieker syndrome,[sup][23] glutaric aciduria type 1,[sup][24],[25] methylmalonic acidaemia,[sup][26] and nonsyndromic microencephaly.[sup][27] However, abnormal operculization on prenatal imaging does not systematically reflect the underlying cortical dysplasia.
The most remarkable differences regard opercular angle (approximately 45[degrees] towards dorsal surface in P.
En las regiones de la mejilla, nuca, area opercular y flancos corporales se encuentran salpicados por pequenas manchas azul iridiscentes, dispuestas en un patron complejo, el cual se vuelve mas intenso durante la fase reproductiva y en organismos machos.
There are many different structures for fish age estimation, such as scales, otoliths, vertebrae and opercular bones (Khan et al.
The clinical signs observed for the fish were increased opercular beat, erratic swimming, inquietude, position along the water column, lethargy, muscle spasm (trembling), corrosion at the body surface (skin and fin) and skin and eyes color (Murty, 1998).
These behaviors are: opercular flaring, swim away (disengaging courtship), biting, lateral roll, caudal sweeping, and most notably, courtship by a single male simultaneously with multiple females at the nest site.
Flatheads were dormant, remaining motionless, with little or no opercular movement.