| AAT | Aachen Aphasia Test; academic aptitude test; alanine aminotransferase; alkylating agent therapy; alp... |
|---|---|
| AS | acetylstrophanthidin; acidified serum; acoustic schwannoma; acoustic stimulation; active sarcoidosis... |
| LAA | left atrial appendage; left atrial area; leukemia-associated antigen; leukocyte ascorbic acid |
| PAS | para aminosalicylate; Parent Attitude Scale; patient administration system; patient appointments and... |
| RAI | radioactive iodine; radioactive isotope; resident assessment instrument; resting ankle index; right ... |
| ectoplasmic tube contraction | <cell biology> Model for amoeboid movement in which it is proposed that protrusion of a pseudopod is brought about by contraction of the sub plasmalemmal region everywhere else in the cell thus squeesing the central cytoplasm forwards. See: frontal zone contraction theory. (18 Nov 1997) |
|---|---|
| tonic contraction | Sustained contraction of a muscle, as employed in the maintenance of posture. (05 Mar 2000) |
| escape contraction | Escaped beat, an automatic beat, usually arising from the A-V junction or ventricle, occurring after the next expected normal beat has defaulted; it is therefore always a late beat, terminating a longer cycle than the normal. Synonym: escape contraction. (05 Mar 2000) |
| escape ventricular contraction | An escape beat arising in the ventricle. (05 Mar 2000) |
| excitation contraction coupling | <physiology> Name given to the chain of processes coupling excitation of a muscle by the arrival of a nervous impulse at the motor end plate to the contraction of the filaments of the sarcomere. The crucial link is the release of calcium from the sarcoplasmic reticulum and the analogy is often drawn between this and stimulus secretion coupling, that also involves calcium release into the cytoplasm. (18 Nov 1997) |
| uterine contraction | Contraction of the uterine muscle. (12 Dec 1998) |
| frontal zone contraction theory | Model proposed to account for the movement of giant amoebae in which cytoplasmic contraction at the front of the leading pseudopod (fountain zone) pulls viscoelastic cytoplasm forward in the centre of the cell and forms a tube of more rigid cytoplasm immediately below the plasma membrane behind the active region. The peripheral contracted cytoplasm relaxes into a weaker gel at the rear and is pulled forward in its turn. Contrasts with the ectoplasmic tube contraction model. (18 Nov 1997) |
| front-tap contraction | Contraction of the calf muscles when the anterior surface of the leg is struck. Synonym: Gowers' contraction. (05 Mar 2000) |
| arrhythmias, atrial | Abnormal heart rhythm due to electrical disturbances in the atria (the upper chambers of the heart) or the AV node relay station , leading to fast heart beats. Examples of atrial arrhythmias includes atrial fibrillation, atrial flutter, and paroxysmal atrial tachycardia (PAT). (12 Dec 1998) |
| atrial | <anatomy> Pertaining to an atrium. (16 Dec 1997) |
| atrial appendage | The small projection from each atrium hanging over like a small ear, more marked on the left, with a small cavity of its own. (05 Mar 2000) |
| atrial arrhythmias | See Arrhythmias, atrial. (12 Dec 1998) |
| atrial arteries | Branches of the right and left coronary arteries distributed to the muscle of the atria. Synonym: arteriae atriales. (05 Mar 2000) |
| atrial auricle | The auricle of atrium. See: left atrium, right atrium. (05 Mar 2000) |
| atrial auricula | A small conical ("ear-shaped") pouch projecting from the upper anterior portion of each atrium of the heart, increasing slightly the atrial volume. See: auricle of left atrium, auricle of right atrium. Synonym: auricula atrialis, atrial auricle, atrial auricula, auricle, auricula, auricular appendage, auricular appendix, skin tag. (05 Mar 2000) |