| 释义 |
pace-maker
[pace n.1]
1. a. A rider (boat's crew, etc.) who makes or sets the pace for another in racing or training for a race. Also, one of the leading runners in a race. Also transf.
1884Pall Mall G. 29 Mar. 2/2 The same scratch-crew acted as pace-maker for both the university eights. 1891Ibid. 6 Aug. 1/3 To establish a record for a mile without pace-makers, in order that comparisons may be drawn between the times of an unassisted rider and one paced. 1900Field 4 Aug. 186/1 Up to this he had been one of the pacemakers, but even now he was not to be left behind. Ibid. 8 Sept. 384/1 The value of the pacemaker as a mere leader who set a racing pace..was lost sight of when his utility as a wind-shield became recognized. 1942Sun (Baltimore) 29 Apr. 19/1 El Toreador scored by three parts of a length over Seaway, pacemaker for most of the mile and 70-yard route of the seventh event. 1951R. & N. McWhirter Get to your Marks! iii. 66 Latching on to an over-awed local pace-maker in a 3-man field, Whitfield swept through. 1957J. Peters et al. Mod. Middle- & Long-Distance Running xii. 55 He..missed a great opportunity of using Hansenne as a pace⁓maker. 1961Times 11 Apr. 14/5 An athlete training with an automatic pacemaker. 1978G. A. Sheehan Running & Being xii. 174 A pacemaker..had zeroed in on the perfect pace.
b. One who sets the rate of working for others or the standards to be achieved by others; a ‘trend-setter’. Also transf., of things.
1906U. Sinclair Jungle xi. 130 They would get new pace-makers and pay them more. 1967Daily Tel. 17 May 17/7 Public schools may well continue to act as pace⁓makers and trend-setters for this country's education as a whole. 1970Ibid. 14 Feb. 9/8 Both Rameau and Gluck were pacemakers in their day, progressive composers who consciously set out to change the musical landscape of the society in which they lived. 1976Star (Sheffield) 30 Nov. 14/4 Chris Guthrie's hopes of a return to face the Second Division's pacemakers Chelsea at Bramall Lane on Friday night soared today. 1977Times 22 Dec. 12/5 Pacemakers to watch in 1978 are..good Victorian dining furniture, early Continental oak and walnut, and tallboys.
2. An apparatus fixed to a bicycle to indicate when the rider is going at the required pace.
1896Godey's Mag. Apr. 377/1 On the same lines is a pace⁓maker that can be set at any desired rate... While this rate is maintained, it rings a bell.
3. Physiol.
a. That part of an animal's heart which determines the rate at which it contracts and where the contractions begin (in man and other mammals normally the sino-atrial node).
1910Heart II. 39 The normal auricular complex is most closely simulated by beats excited from the neighbourhood of Keith and Flack's node. The pace-maker of the heart is therefore situated in the neighbourhood of the superior cavo-auricular junction. 1927Haldane & Huxley Animal Biol. vii. 146 In a mammal the beat starts at the entrance of the great veins to the right auricle in a special piece of tissue known as the ‘pace⁓maker’ which does not contract but stimulates the neighbouring muscle. 1951Ann. Surg. CXXXIV. 8/2 Pratt..stated that the pacemaker is governed, at least in part, by the chemical content of venous blood returning to the right auricle. 1961Lancet 9 Sept. 574/1 After a 550-volt shock complete auriculo-ventricular dissociation with a nodal or high bundle pacemaker at a rate of 30 per minute evolved spontaneously. 1968Passmore & Robson Compan. Med. Stud. I. xxviii. 10/2 If the rate of discharge of the SA node is depressed, the portion of the heart with the next highest spontaneous discharge rate becomes the pacemaker, usually the AV [sc. atrioventricular] node.
b. A structure which controls the rate of rhythmic activity of an organ other than the heart.
1949Koestler Insight & Outlook xx. 138 A certain region near the sinus end of the heart controls the rate of beat, and similar ‘pacemakers’ function in the stomach, the ureters, and so forth. 1963R. P. Dales Annelids vi. 132 If there are two pacemakers maintaining two muscular activities it may well be asked if one can dominate the other. 1966S. Ochs in E. E. Selkurt Physiol. (ed. 2) vi. 147 A pacemaker for rhythmicity of the EEG wave was located in the thalamus. 1974McLennan & Sandberg Synopsis Obstetr. (ed. 9) x. 145 Any group of excited myometrial cells anywhere in the uterus may serve in the pacemaker role and initiate electrical propagation throughout the myometrium.
c. A man-made device which supplies electrical signals to the heart, stimulating it to beat at an appropriate rate.
1951Ann. Surg. CXXXIV. 9/1 Our attention has been directed to the study of the problem of cardiac arrest to determine if the use of an electrical artificial pacemaker in resuscitation would be of value. 1963Daily Tel. 16 Apr. 17/1 A transistorised pacemaker little bigger than a match box and weighing only a few ounces has been devised for implanting in the abdominal wall. 1967New Scientist 9 Feb. 331/1 Battery-powered pacemakers normally need their batteries replacing after no more than 2–3 years, needing a surgical operation each time. 1974Times 4 Mar. 6/6 He is to undergo an operation for the installation of a pacemaker to help him overcome a heart condition which has affected him on several recent occasions.
Add:[3.] [c.] Cf. *pacer n. 5. |
