释义 |
sino-atrial, a. Anat.|saɪnəʊˈeɪtrɪəl| Also sinoatrial. [f. sino-2 + atrial a.] Of, pertaining to, or designating a small body of tissue (the sino-atrial node) in the wall of the right atrium of the heart that acts as a pacemaker by producing a contractile signal at regular intervals; (so called because it arises in the embryo at the junction of the sinus venosus and the atrium). Cf. sinuatrial a.
1913Gray's Anat. (ed. 18) 552 The sino-atrial node is situated on the anterior border of the opening of the superior vena cava. 1962Listener 10 May 810/1 A small mass of specialized muscle cells within the heart, the sino-atrial node, discharges a brief electric ‘spark’ regularly seventy-two times a minute or thereabouts. 1969[see dysrhythmia s.v. dys-]. |