释义 |
DictionarySeevalvethebesian valve
valve [valv] a membranous fold in a canal or passage that prevents backward flow of material passing through it.aortic valve a valve" >semilunar valve that separates the left ventricle and the aorta; it opens with end diastole, causing the second heart sound.atrioventricular v's the valves" >cardiac valves between the right atrium and right ventricle (tricuspid valve) and the left atrium and left ventricle (mitral valve).bicuspid valve mitral valve.bicuspid aortic valve a congenital anomaly of the aortic valve, caused by incomplete separation of two of the three cusps; it is generally asymptomatic early in life but is predisposed to calcification and stenosis later on.Braschi valve a one-way valve put into the inspiratory limb of a ventilator circuit in order to measure the pressure" >intrinsic positive end-expiratory pressure.cardiac v's valves that control flow of blood through and from the heart.coronary valve a valve at the entrance of the coronary sinus into the right atrium.flail mitral valve a valve" >mitral valve having a cusp that has lost its normal support (as in ruptured chordae tendineae) and flutters in the blood stream.heart v's cardiac valves.Heimlich valve a small one-way valve used for chest drainage, emptying into a flexible collection device; the valve prevents return of gases or fluids into the pleural space. The Heimlich valve is less than 13 cm (5 inches) long and facilitates patient ambulation; it can be used in many patients instead of a traditional water seal drainage system.ileocecal valve (ileocolic valve) the valve guarding the opening between the ileum and cecum.mitral valve the valve" >cardiac valve between the left atrium and left ventricle, usually having two cusps (anterior and posterior). Called also bicuspid valve.Valves of the heart. The right heart pumps the venous blood into the lungs. The oxygenated blood returns from the lungs into the left atrium and is propelled by the left ventricle into the aorta. The insets show closed valves: the tricuspid valve has three leaflets, whereas the mitral valve has two leaflets. The aortic and pulmonary artery valves have three leaflets and resemble one another except for the fact that the coronary arteries originate from behind the cusps in the aorta. From Damjanov, 1996.posterior urethral valve any of various types of congenital folds across the proximal part of the male urethra near the colliculus" >seminal colliculus, the most common cause of urethral obstruction in male infants.pulmonary valve (pulmonic valve) the pocketlike valve" >cardiac valve that protects the orifice between the right ventricle and the pulmonary artery.pyloric valve a prominent fold of mucous membrane at the pyloric orifice of the stomach.semilunar v's the valves" >cardiac valves that have cusps" >semilunar cusps; see aortic valve and pulmonary valve.thebesian valve coronary valve.tricuspid valve the valve" >cardiac valve guarding the opening between the right atrium and right ventricle.valve of vein (venous v's) any of the small cusps or folds found in the tunica intima of many veins, serving to prevent backflow of blood.valve of cor·o·nar·y si·nus [TA] a delicate fold of endocardium at the opening of the coronary sinus into the right atrium. Synonym(s): valvula sinus coronarii [TA], coronary valve, thebesian valvevalve (valv) [L. valva, leaf of a folding door] Any of various membranous structures in a hollow organ or passage that temporarily close to permit the flow of fluid in one direction only.aortic valve Abbreviation: AoV The valve at the junction of the left ventricle and the ascending aorta. It is composed of three segments (semilunar cusps) and prevents regurgitation. See: cardiac valve for illus. Bauhin valve See: Bauhin valveBéraud valve See: Béraud valvebicuspid valveMitral valve.Bjork-Shiley heart valveA synthetic artificial heart valve that is no longer commercially available but remains implanted in thousands of patients. The valve has been known to fracture at its struts during use, which results in death in the majority of cases. CARDIAC VALVES: with ventricles relapsedcardiac valveAny of the four valves that prevent the backflow of blood as it passes into, through, and out of the heart. In order of the entry of the venous blood into the right atrium, they are the tricuspid, pulmonary, mitral, and aortic. See: illustrationCarpentier-Edwards valve See: Carpentier-Edwards valve.check valveA valve that permits fluids or gases to flow in just one direction. Check valves are used in infusion sets to prohibit backflow of fluids during intravenous therapy. coronary valveThe coronary sinus valve at the entrance of the coronary sinus into the right atrium. Synonym: thebesian valveeustachian valveThe valve at the entrance of the inferior vena cava.external nasal valveThe outermost opening of the nose (the alar rim).flutter valveA one-way valve used in chest tube drainage systems that allows fluids or gases to flow out of the chest, but does not let them reenter the body Synonym: Heimlich flutter valve; Heimlich valveGerlach valve See: Gerlach valvehigh-pressure relief valveA safety device built into a ventilator circuit that protects the patient from excessively high airway pressures by venting excess pressure into the atmosphere.Houston valve See: Houston valveHuschke valveLacrimal plica.ileocecal valveA projection of two membranous folds of the ileum of the small intestine into the cecum of the colon. It prevents backup of fecal material into the small intestine. Synonym: valvula coliinspiratory impedance threshold valve See: inspiratory impedance threshold valveinternal nasal valveNasal valve.Krause valve See: Krause, Karlleft atrioventricular valveMitral valve.mitral valveThe valve that closes the orifice between the left cardiac atrium and the left ventricle during ventricular systole. Synonym: bicuspid valve; left atrioventricular valvenasal valveThe site of greatest obstruction to airflow through the nasal passages. It extends from the bony cave near the piriform aperture into part of the cartilaginous vestibule of the nose. Synonym: internal nasal valvepop-off valveA safety valve that releases gas into the atmosphere from a ventilator circuit when the pressure in the circuit exceeds a known, safe level.TYPES OF MECHANICAL HEART VALVES: A. caged ball valve; B. monoleaflet. C. bileafletprosthetic heart valveA substitute valve used to replace a diseased valve. There are two main types of prostheses: those made from biological tissues, e.g., the heart valves of animals, esp. pigs, and those made from biocompatible materials, e.g., metals or polymers. Biocompatible mechanical valves may be constructed in a variety of ways, e.g., from a ball that moves up and down in a cage; with bileaflet valves that close in the midline; or with a single leaflet (which tilts to open and close). See: illustrationpulmonary valveThe valve at the junction of the right ventricle and pulmonary artery. It is composed of three semilunar cusps and prevents regurgitation of blood from the pulmonary artery back into the right ventricle. See: cardiac valve for illus. pyloric valveThe prominent circular membranous fold at the pyloric orifice of the stomach. Synonym: valvula pylorireducing valveA device to reduce the pressure of gas that has been compressed in a cylinder.right atrioventricular valveTricuspid valve.semilunar valveThe type of valve separating the heart and aorta and the heart and pulmonary artery. See: cardiac valve for illus. thebesian valveCoronary valve.tricuspid valve Abbreviation: TV The valve that closes the orifice between the right cardiac atrium and right ventricle during ventricular systole. Synonym: right atrioventricular valve; valvula tricuspidalis See: cardiac valve for illus. valve of VaroliusIleocecal valve.Thebesius, Adam C., German physician, 1686-1732. thebesian foramina - a number of fossae in the wall of the right atrium containing the openings of minute intramural veins. Synonym(s): foramina of the venae minimaethebesian valve - a delicate fold of endocardium at the opening of the coronary sinus into the right atrium. Synonym(s): valve of coronary sinusthebesian veins - numerous small valveless venous channels that open directly into the chambers of the heart from the capillary bed in the cardiac wall, enabling a form of collateral circulation unique to the heart. Synonym(s): venae cordis minimae |