annulus


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Related to annulus: Annulus fibrosus, Annulus of Zinn

annulus

 [an´u-lus] (pl. an´nuli) (L.)
alternate spelling of anulus.

annulus

/an·nu·lus/ (an´u-lus) pl. an´nuli   [L.] anulus.

annulus

(ăn′yə-ləs)
n. pl. annu·luses or annu·li (-lī′)
1. A ringlike figure, part, structure, or marking, such as a growth ring on the scale of a fish.
2.
a. A ring or group of thick-walled cells around the sporangia of many ferns that functions in spore release.
b. The ringlike remains of a broken partial veil, found around the stipes of certain mushrooms.

annulus

annulus

Any ring-like structure (e.g., mitral valve annulus).

annulus

Any ring-like structure.

annulus

  1. the ring of cells in the moss or fern capsule which splits to allow the liberation of spores.
  2. a ring of tissue surrounding the stalk in the fruiting bodies of the BASIDIOMYCOTA fungi.

annulus, anulus

pl. annuli, anuli [L.] a small ring or encircling structure.

atrioventricular annulus
a ring of Purkinje cells around the right A-V orifice that serves the myocardium and valves locally and also serves as an alternative connection between the atria and the ventricles.
fibrocartilaginous annulus
the circular pad which connects the tympanic membrane to the external acoustic meatus.
annuli fibrosi
1. four fibrous rings at the base of the heart to which the myocardium is attached, one around each A-V orifice and one each around the aorta and the pulmonary artery.
2. the intervertebral disks consist of a soft central pulpy nucleus and a peripheral annulus fibrosus.
annulus iridis
the iris consists of two rings, an inner smooth annulus iridus minoris, and an outer plicated part, the annulus iridis major.
annulus preputialis
the ring of skin marking the entrance to the cavity of the prepuce.
annulus sclerae
a roll of connective tissue on the inside of the sclera at the corneoscleral junction.
spermatic annulus
a small ring condenses around the proximal centriole of the spermatid.
annulus vaginalis
the ring through which the peritoneal cavity connects with the cavity of the vaginal tunic.
References in periodicals archive ?
The insulation material is either pre-attached to the flowline prior to insertion into the jacket pipe or the annulus is filled once the flow line has been inserted inside the jacket pipe.
When this occurs, the disc protrudes into the IVF and can compress the nerve root, causing symptoms into the lower extremity on that side (midline posterior bulges/herniations occur less frequently because the annulus fibrosus is reinforced in the midline by the posterior longitudinal ligament).
Similarly, the numerical predictions of friction pressure gradients in the case of a power law fluid in an eccentric annulus (Table 2, case a) are compared in Figure 4 to the experimental data published by Mitsuishi and Aoyagi [26].
The birth date and date of annulus completion was assigned as 1 November, which represents the mid spawning period for both species (McPherson, 1993; Welch et al.
They become decoupled from the main annulus and don't come back," he added.
The innermost wall layer of wax in the annulus adjacent to the metal wall melts quickly as the temperature of water is greater than the melting point of wax, and a layer of melt surrounds the metal tube.
It is at the annulus that the powerful whip-like beat of a sperm's tail begins.
At the service point furthest from the inserted end of the PE, the main was drilled under 'no gas' conditions to allow the injection of Insertion Seal foam into the annulus.
As this was a variation on the previous experiences, further welding, manufacturing and inspection procedures were developed and full-scale trial assemblies were PE lined as individual pipe strings, welded as double joins for installation trials and subjected to pressure testing and leak detection of the PE annulus.
In contrast, participants with aortic annulus calcification or aortic sclerosis had no increased risk of either cardiovascular or all-cause mortality, according to Dr.
Answer from Tom Knowles at ARDL): An annulus is a donut-like ring cut from a standard tensile sheet.
Annuloplasty rings are indicated for repair of the mitral valve and are designed to remodel the anatomical shape of the mitral annulus, thus preventing further dilatation and minimizing the risk of late repair failures.