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991.
Aspects of capillary refilling time (CRT) in newborns, such as pressing time, sites of testing, normal values and difference between observers were assessed. CRT was measured in 280 term newborns, divided into 7 groups of 40 each, varying pressing time (from 1 to 7 s) was applied. CRT was measured in midpoints of forehead and sternum and plantar surface of heel (defined as head, chest and heel). No statistically significant difference was found between 3 and 7 s pressing time groups. The data points of the CRT of the head and chest approached normality, whilst those of the heel were widely scattered. Normal CRT in newborns is <3 s. No significant difference between two observers in head and chest CRT values was found.  相似文献   
992.
Nuclear magnetic resonance proton imaging was used to obtain images of goat fetuses in utero. The long T1 relaxation time of amniotic fluid makes it appear black on proton density images when examined using the Aberdeen imager, and so allows very good discrimination of the position and structure of the fetus. Some fetal internal tissues can be seen on T1 images. These findings suggest that NMR imaging has great potential in pregnancy studies.  相似文献   
993.
994.
In the Physicians' Health Study, a randomized, placebo-controlled, double-blind trial of aspirin in the reduction of cardiovascular mortality and beta-carotene in decreasing cancer incidence, 33,223 subjects were eligible and willing to enter the trial. Instead of randomizing this group immediately, all participants received identical calendar packs that contained active aspirin and beta-carotene placebo. Following an 18-week run-in, only 22,071 subjects who remained eligible and willing and had taken at least 2/3 of their pills were randomized. We estimated the effect of the run-in as follows: pill taking compliance increased 20-41 per cent; sample size decreased 34 per cent; duration of follow-up decreased 7 per cent which resulted in a 7 per cent decrease in the expected event rate for the placebo group. To estimate these changes, we made assumptions about compliance and outcome risk for those excluded by the run-in. Our conclusion, however, about the net effect of the run-in on the power of the study remains constant across variations in a number of those assumptions. The power with the run-in, with 22,071 good compliers was typically higher, and never more than negligibly lower, than the power without the run-in, with 33,223 good and poor compliers. In addition, savings from enrolling 11,152 fewer subjects in the trial resulted from the use of the run-in.  相似文献   
995.
D G Maki  C H Hennekens  J V Bennett 《JAMA》1972,221(11):1270-1271
  相似文献   
996.
In a retrospective study of 503 well-documented cases of primary malignant melanoma (stage I) clinical criteria were analysed for their prognostic relevance. The maximum elevation (in mm) of the tumour was found to be the most important single prognostic factor. There was a close association with tumour thickness, measured histologically by the method of Breslow (correlation coefficient = 0.73). A combination of elevation and three additional clinical criteria (site, nodule- or lesion-diameter, and surface defects such as erosion, ulceration or bleeding) allowed a further improvement in prognostic accuracy. This clinical classification into low-risk and high-risk melanomas was as effective as the use of tumour thickness measured histologically, and can therefore be used for the preoperative planning of treatment.  相似文献   
997.
998.
The nurses' health study.   总被引:2,自引:0,他引:2  
  相似文献   
999.
ABSTRACT. Forty-five high risk infants were examined in a neonatal nursery with a real-time ultrasound scanner. The relevant normal and abnormal intracranial features are described. There was a good correlation betwen the site and size of the 12 intraventricular haemorrhages (IVH) found on ultrasound scanning with subsequent computerised axial tomography (CAT) scans and postmortem results. There was also close agreement between CAT and ultrasound scan assessment of ventricular size. Our data suggest that IVH occurs within the first 48 hours of life. In the light of our experience and because of its convenience and safety we have largely abandoned CAT scanning in favour of real-time ultrasound scanning in the investigation of neonatal IVH and hydrocephaly.  相似文献   
1000.
Effects of beer, wine, and liquor in coronary deaths.   总被引:6,自引:0,他引:6  
C H Hennekens  W Willett  B Rosner  D S Cole  S L Mayrent 《JAMA》1979,242(18):1973-1974
For a series of 568 married men who died of coronary heart disease and an equal number of matched control subjects, information was collected on a large number of variables, including daily alcohol consumption classified by type of beverage, namely, beer, wine, or liquor. Daily consumption of small to moderate amounts of alcohol (2 oz [59.2mL] or less daily) was inversely related to coronary death. This inverse relation was present in both crude and adjusted matched-pair analyses and was similar for each type of alcohol, as indicated by adjusted relative risks of 0.3 for beer, 0.3 for wine, and 0.2 for liquor. In contrast, for heavy drinking, there was no association with coronary death in either crude or adjusted analyses.  相似文献   
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