| upper respiratory infection | Any number of viral or bacterial infections that includes infections of the throat, nasopharynx, sinuses, larynx, trachea or bronchi. (27 Sep 1997) |
|---|---|
| upper respiratory tract | The nasopharynx, oral cavity, and throat. (09 Oct 1997) |
| upper subscapular nerve | Two branches of the posterior cord of the brachial plexus, an upper and lower, supplying the subscapularis muscle; the lower subscapular nerve also supplies the teres major muscle. Synonym: nervi subscapulares. (05 Mar 2000) |
| upper thoracic splanchnic nerves | Part of the cardiopulmonary splanchnic nerves from the second to fifth segments of the thoracic sympathetic trunk that pass medially and anteriorly to enter the cardiac plexus; they convey postsynaptic sympathetic fibres to, and visceral afferent (pain) fibres from, the heart. Synonym: nervi cardiaci thoracici, upper thoracic splanchnic nerves. (05 Mar 2000) |
| upper uterine segment | The main portion of the body of the gravid uterus, the contraction of which furnishes the chief force of expulsion in labour. (05 Mar 2000) |
| anastomotic branch of middle meningeal artery to lacrimal artery | <anatomy, artery> A branch of the middle meningeal artery arising in the cranial cavity which runs anteriorly through the superior orbital fissure to anastomose with the lacrimal artery. See: orbital branch of middle meningeal artery. Synonym: ramus anastomoticus arteriae meningeae mediae cum lacrimali. (05 Mar 2000) |
| abdominal aortic aneurysm | <surgery> A distended and weakened area in the wall of the abdominal aorta, more common in those who suffer from atherosclerosis. Symptoms include sudden, severe abdominal pain with radiation to the back. (27 Sep 1997) |
| ampullary aneurysm | A saclike bulging on one side of an artery. Synonym: ampullary aneurysm. (05 Mar 2000) |
| aneurysm | <anatomy, surgery> A sac formed by the dilatation of the wall of an artery, a vein or the heart. The physical signs of arterial aneurysm are the formation of a pulsating tumour and often a bruit (aneurysmal bruit) heard over the swelling. Sometimes there are symptoms from pressure on contiguous parts. Origin: Gr. Aneurysma = a widening (18 Nov 1997) |
| aneurysm by anastomosis | A mass of dilated anastomosing vessels that produce a pulsating tumour usually in a superficial position. (05 Mar 2000) |
| aneurysm, dissecting | Splitting or dissection of an arterial wall by blood entering through an intimal tear or by interstitial haemorrhage. It is most common in the aorta. (12 Dec 1998) |
| aneurysm, false | An aneurysm in which the entire wall is injured and the blood is contained by the surrounding tissues, with eventual formation of a sac communicating with the artery or heart. (12 Dec 1998) |
| aneurysm, infected | Aneurysm due to growth of microorganisms in the arterial wall, or infection arising within preexisting arteriosclerotic aneurysms. (12 Dec 1998) |
| aneurysm of sinus of Valsalva | A congenital thin-walled tubular out pouching usually in the right or non-coronary sinus with an entirely intracardiac course that may rupture into the right or rarely the left heart chambers to form an aortocardiac fistula. (05 Mar 2000) |
| aneurysm, ruptured | The tearing or herniation of the weakened wall of the aneurysmal sac. (12 Dec 1998) |