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Serum zinc and copper levels were measured longitudinally in 55 healthy middle and upper socio-economic group white mothers living in Cape Town from the birth of the baby to 12 months after parturition. Mean maternal serum zinc levels showed a significant rise (P less than 0.05) from delivery (66.34 +/- 21.07 micrograms/100 ml) to 12 weeks (87.88 +/- 15.93 micrograms/100 ml), but no further changes were detected at 24, 36 and 52 weeks after parturition. The mean maternal serum copper levels decreased from 217.73 +/- 64.34 micrograms/100 ml at delivery to 141.65 +/- 45.60 micrograms/100 ml at 12 weeks (P less than 0.05); they remained constant at all the other sampling periods. No differences (P greater than 0.05) were noted at all the different sampling periods between mean serum zinc levels of primiparous and multiparous mothers, but mean serum copper levels were significantly higher (P less than 0.05) in the primiparas. The mean serum zinc and copper levels of healthy white South African mothers at delivery and 12 months after parturition correspond with those for Northern American mothers. Normal non-pregnant adult serum zinc and copper levels were attained within 12 weeks of delivery.  相似文献   
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A scoring system for identification of men at high risk of a heart attack within 5 years of screening is presented. The full scoring system includes an electrocardiogram and blood cholesterol measurement and the top fifth of the distribution of this full score yields 59% of the major ischaemic heart disease events occurring in the 5 years after screening. An intermediate scoring system, without an electrocardiogram but retaining blood cholesterol, yields 58% of cases from the top fifth of the score distribution. A basic (GP) score, without electrocardiogram or blood cholesterol measurement, yields 54% of cases and is recommended for use in opportunistic screening in general practice. This high risk strategy would increase public awareness of the size of the problem, help to prevent premature death and provide a useful complement to the population strategies of health education and government policy.  相似文献   
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J B Barlow  W A Pocock 《Herz》1988,13(4):227-234
The syndrome of primary mitral leaflet billow, with or without prolapse, is associated with myxomatous degeneration of the mitral valve apparatus, mainly the posterior leaflet, and the syndrome may be familial. It manifests clinically with an isolated nonejection systolic click (billow), a murmur of mitral regurgitation that is usually late systolic (prolapse), or a combination of murmur and click. Echocardiography identifies and assesses the extent of the billowing of mitral leaflet bodies but there are no specific echocardiographic criteria that can differentiate normal from pathological billowing. Similarly, a prolapsed leaflet is not detected echocardiographically when there is localized and mild failure of leaflet edge apposition but a more severely prolapsed, or flail, leaflet can be demonstrated and confirmed by that technique. Symptoms of the syndrome include anxiety, chest pain and palpitations. The resting electrocardiogram may show ST segment and T wave abnormalities. The majority of patients have a benign course and require reassurance only. Complications include systemic emboli, infective endocarditis, progression to severe mitral regurgitation, arrhythmias and, rarely, sudden death. Patients with prolapse of a leaflet edge are more likely to develop complications than those with only billowing of the leaflet bodies. Surgery, preferably valvuloplasty, is required for severe regurgitation and may also be indicated for potentially lethal tachyarrhythmias unresponsive to medical therapy. Mitral leaflet billow and prolapse may be secondary to, or associated with, many conditions. The prognosis is then principally that of the underlying disease of which ischemic heart disease and hypertrophic cardiomyopathy are the most important.  相似文献   
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Blood lead concentration in children after gunshot injuries   总被引:1,自引:0,他引:1  
Blood lead and erythrocyte zinc protoporphyrin values were examined in 23 children who had suffered gunshot (including multiple shotgun) injuries. No child had any evidence of lead poisoning between 15 and 27 months after the injury despite, in some cases, the retention of multiple pellets. Reference to previous publications suggests that lead poisoning is an unlikely complication of gunshot injury, providing a bullet or pellet is not retained in contact with a synovial cavity.  相似文献   
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