| breath-holding | Voluntary or involuntary cessation of breathing; often seen in young children as a response to frustration. (05 Mar 2000) |
|---|---|
| breath-holding test | A rough index of cardiopulmonary reserve measured by the length of time that a subject can voluntarily stop breathing; normal duration is 30 seconds or more; diminished cardiac or pulmonary reserve is indicated by a duration of 20 seconds or less. (05 Mar 2000) |
| lion-jaw bone-holding forceps | A sturdy forceps with strong sharp teeth in the jaws, used for holding bone fragments. (05 Mar 2000) |
| vortex | Origin: L. Vortex, vertex, -icis, fr. Vortere, vertere, to turn. See Vertex. 1. A mass of fluid, especially of a liquid, having a whirling or circular motion tending to form a cavity or vacuum in the center of the circle, and to draw in towards the center bodies subject to its action; the form assumed by a fluid in such motion; a whirlpool; an eddy. 2. A supposed collection of particles of very subtile matter, endowed with a rapid rotary motion around an axis which was also the axis of a sun or a planet. Descartes attempted to account for the formation of the universe, and the movements of the bodies composing it, by a theory of vortices. 3. <zoology> Any one of numerous species of small Turbellaria belonging to Vortex and allied genera. <chemistry> Vortex atom, a hypothetical ring-shaped mass of elementary matter in continuous vortical motion. It is conveniently regarded in certain mathematical speculations as the typical form and structure of the chemical atom. Vortex wheel, a kind of turbine. Source: Websters Dictionary (01 Mar 1998) |
| vortex coccygeus | A spiral arrangement of coarse hairs sometimes present over the region of the coccyx. Synonym: coccygeal whorl. (05 Mar 2000) |
| vortex cordis | A spiral arrangement of muscular fibres at the apex of the heart. Synonym: vortex cordis, whorl. (05 Mar 2000) |
| vortex lentis | One of the stellar figures on the surface of the lens of the eye. Synonym: vortex. (05 Mar 2000) |
| vortex of heart | A spiral arrangement of muscular fibres at the apex of the heart. Synonym: vortex cordis, whorl. (05 Mar 2000) |
| vortex veins | Several veins (usually four) from the vascular tunic formed of veins accompanying the posterior ciliary arteries and the ciliary body; then drain into the superior or inferior ophthalmic vein. Synonym: venae vorticosae, venae choroideae oculi, choroid veins of eye, Stensen's veins, vasa vorticosa, vorticose veins. (05 Mar 2000) |
| Fleischer's vortex | Congenital whorl-like opacities in the cornea. Synonym: Fleischer's vortex. (05 Mar 2000) |
| abnormal heart chamber dimensions | <radiology> Left ventricular volume overload, left ventricular hypertrophy, right ventricular volume overload, right ventricular hypertrophy, fixed subvalvular aortic stenosis, hypoplastic left/right ventricle; common ventricle, congestive cardiomyopathy (12 Dec 1998) |
| air chamber | 1. A chamber or cavity filled with air, in an animal or plant. 2. A cavity containing air to act as a spring for equalizing the flow of a liquid in a pump or other hydraulic machine. Source: Websters Dictionary (01 Mar 1998) |
| altitude chamber | A decompression chamber for simulating a high altitude environment, particularly its low barometric pressure. Synonym: high altitude chamber. (05 Mar 2000) |
| anechoic chamber | A room designed to absorb all sound so as to eliminate all echoes; used for isolation and sound research on human subjects. (05 Mar 2000) |
| anterior chamber | The space in the eye, filled with aqueous humor, bounded anteriorly by the cornea and a small portion of the sclera and posteriorly by a small portion of the ciliary body, the iris, and that part of the crystalline lens which presents through the pupil. (12 Dec 1998) |