| alpha-blocker | An agent that competitively blocks alpha-adrenergic receptors; used in the treatment of hypertension. Synonym: alpha-blocker. (05 Mar 2000) |
|---|---|
| beta-blocker | <pharmacology> A large group of medications that act to block specific receptors in the nervous system. A drug that induces adrenergic blockade at either á1 or á2 adrenergic receptors or at both. The effect of beta-blockade results in slowing of the heart rate, reduction in blood pressure and reduced anxiety. Beta-blockers are used in the treatment of angina, heart arrhythmias, high blood pressure, mitral valve prolapse and other conditions. (06 Oct 1997) |
| blocker | 1. An instrument used to obstruct a passage. See: blocking agent. (05 Mar 2000) |
| calcium channel-blocker | <pharmacology> A class of drugs that act by selective inhibition of calcium ion influx through or across cell membranes or on the release and binding of calcium in intracellular pools. Calcium channel blockers are used primarily in the treatment of certain heart conditions and stroke. As they are inducers of vascular and other smooth muscle relaxation, they are also used in the treatment of hypertension and cerebrovascular spasms, as myocardial protective agents, and in the relaxation of uterine spasms. Synonym: calcium antagonist, calcium channel-blocker, slow channel-blocking agent. (12 May 2002) |
| medication, beta-blocker | Drugs that antagonise the action of adrenaline (a beta adrenergic substance) and relieve stress to the heart muscle. Beta-blockers are often used to slow the heart rate or lower the blood pressure. (12 Dec 1998) |
| H2 blocker | <pharmacology> A class of anti-ulcer medication which work through the inhibition of basal and nocturnal gastric acid secretion by competitive inhibition of the action of histamine at histamine H2 receptor sites on the parietal cells. Drugs of this type block gastric acid secretion and are therefore clinically useful in treating duodenal ulcers. Examples include cimetidine (Tagamet), famotidine (Pepcid), nizatidine (Axid) and ranitidine (Zantac). (27 Sep 1997) |
| bronchial | <anatomy> Pertaining to one or more bronchi. Origin: L. Bronchialis (13 Nov 1997) |
| bronchial adenoma | <radiology> Most common benign lung tumour (but only 1/50 as common as carcinoma), malignant potential, 75% resemble carcinoid tumour or cylindroma, possibly benign form of oaT-cell tumour, haemoptysis, bronchial obstruction most likely to be air-trapping (12 Dec 1998) |
| bronchial anatomy | <radiology> Normal anatomy: right bronchus: eparterial, left bronchus: hyparterial, may help determine situs (12 Dec 1998) |
| bronchial arteries | Left bronchial arteries arise from the thoracic aorta, the right from the first aortic intercostal or the upper left bronchial artery; they supply the bronchi and the lower trachea. (12 Dec 1998) |
| bronchial asthma | A condition of the lungs in which there is widespread narrowing of airways, varying over short periods of time either spontaneously or as a result of treatment, due in varying degrees to contraction (spasm) of smooth muscle, oedema of the mucosa, and mucus in the lumen of the bronchi and bronchioles; these changes are caused by the local release of spasmogens and vasoactive substances (e.g., histamine, or certain leukotrienes or prostaglandins) in the course of an allergic process. (05 Mar 2000) |
| bronchial atresia | Severe focal narrowing or obliteration of a segmental or lobar bronchus, usually associated with distal air trapping. (05 Mar 2000) |
| bronchial breathing | Breath sounds of a harsh or blowing quality, heard on auscultation of the chest, made by air moving in the large bronchi and barely, if at all, modified by the intervening lung; duration of the expiratory sound is as long as or longer than that of the inspiratory sound, and its pitch as high as or higher than that of the inspiratory sound; may be heard over a consolidated lung, above a pleural effusion due to an underlying compressed lung, and rarely over a pulmonary cavity; whispered pectoriloquy is another manifestation that usually can be elicited when bronchial breathing is present. (05 Mar 2000) |
| bronchial bud | One of the outgrowths from the primordial endodermal laryngotracheal tube giving rise to the primary bronchi. See: laryngotracheal diverticulum. (05 Mar 2000) |
| bronchial calculus | A hard concretion in a bronchus or bronchial tube. Synonym: bronchial calculus. Origin: broncho-+ G. Lithos, stone (05 Mar 2000) |