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71.
72.
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography. 相似文献
73.
Background
Adolescents are at risk for acquiring sexually transmitted infections (STIs). However, test rates among adolescents in the Netherlands are low and effective interventions that encourage STI testing are scarce. Adolescents who attend vocational schools are particularly at risk for STI. The purpose of this study is to inform the development of motivational health promotion messages by identifying the psychosocial correlates of STI testing intention among adolescents with sexual experience attending vocational schools. 相似文献74.
G Godin A Colantonio G M Davis R J Shephard C Simard 《Journal of clinical psychology》1986,42(2):272-279
The aim of this study was to predict leisure time exercise behavior among a group of 62 lower-limb disabled adults. The theory of reasoned action proposed by Fishbein (Fishbein & Ajzen, 1975) provided a framework for the study. Variables measured included the Fishbein model variables, habit, education, disability type, fitness level, and a 7-day follow-up of exercise behavior. Some 35% of the variance in exercise behavior could be explained; intention was the strongest predictor (.31, p less than .05). In comparison, the ability to predict intentions to exercise by using the other variables was quite poor, with only 7% of the variance explained by habit. None of the Fishbein model variables contributed to this prediction. These results indicated the importance of specific factors, such as the strength of the exercise habit and the cause of disability, on exercise behavior. 相似文献
75.
The biology and medicine of sailing 总被引:2,自引:0,他引:2
R J Shephard 《Sports medicine (Auckland, N.Z.)》1990,9(2):86-99
The physiological demands of sailing are highly specific, varying with wind conditions, type of craft, and crew position. In a light wind, the only physiological variable yet shown to influence performance is the resting blood sugar. Under high wind conditions, the skipper should be light (less than 60 kg), but crew members should be heavy (greater than 80 kg). Height does not seem a great advantage to crew, possibly because they then lack the muscular strength to exploit the added leverage. Muscle strength, endurance and a tolerance of anaerobic metabolism are all desirable attributes of crew, and competitive performance can be improved by a winter training programme that develops these aspects of muscle performance in the abdominal and thigh regions. The skipper must meet intense and prolonged cerebral demands in the face of periodic isometric work; performance may thus be helped by ingestion of carbohydrate over the course of a race. The ability to sustain isometric contractions in the 'hiking' position may also be improved if the muscles are preloaded with glycogen. The combination of a heavy body build, above average age for an athlete and sustained isometric contraction probably makes the yachting enthusiast vulnerable to ischaemic heart disease. Advisors to a sailing team must further take account of the risks presented by immersion in cold water, loss of sleep, circadian variations of performance over an event, and problems of motion sickness in rough weather. 相似文献
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77.
History of Anaesthesia 总被引:1,自引:0,他引:1
David A. E. Shephard 《Journal canadien d'anesthésie》1989,36(2):224-241
John Snow's leadership in epidemiology as well as anaesthesia resulted from his research as much as his clinical practice. In anaesthesia, Snow's research concerned the regulation of concentrations of volatile agents and the development of efficient inhalers; the uptake and elimination of volatile agents; stages of anaesthesia; carbon dioxide metabolism and rebreathing; and metabolism in anaesthesia and the theory of anaesthesia. In epidemiology, Snow investigated the relationship of water supplies to mortality in cholera during the London epidemic in 1854, which led him to formulate an original and valid theory of the transmission of cholera. Snow's research, which has received less attention than anecdotes concerning his career (e.g., his anaesthetizing Queen Victoria and urging removal of the handle of a contaminated water pump), was always directed towards solving specific problems. The significance of his research is evident in its leading not only to improvements in health care but also to the evolution of anaesthesia and epidemiology as professional disciplines. 相似文献
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80.
J P Miller I D Heath S K Choraria N W Shephard R V Gajendragadkar A W Harcus G A Batson D W Smith R Saynor 《Clinica chimica acta; international journal of clinical chemistry》1988,178(3):251-259
A multicentre, double blind, randomised between-group study comparing the triglyceride lowering effect of MaxEPA, a natural marine oil, and a placebo control is described. Eighty-six patients with hypertriglyceridaemia (fasting serum triglyceride greater than or equal to 2 mmol/l) were studied for three months. There were no significant differences between the groups (48 active, 38 control) in respect of age, sex, height or weight, smoking habits or alcohol consumption. After one month triglyceride levels were reduced significantly from baseline in the treatment group and there was also a highly significant difference between the groups in favour of the marine oil. There was no significant change in serum total cholesterol in either group but there were fluctuations in high density lipoprotein (HDL) in both groups. Minor gastrointestinal side effects were reported by patients in both groups. Standard haematological and biochemical tests were done and there were no significant changes from baseline. 相似文献