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1.
A randomised controlled trial of 554 women was carried out to compare the effects of late and early umbilical cord clamping on the time of cord separation. In addition data were collected on maternal and neonatal outcomes. There were no significant differences between the two groups in the duration of cord adherence and neonatal and maternal outcomes. There appeared to be a higher rate of jaundice in the late clamped group which did not reach statistical significance. There was an unexpectedly higher rate of breast feeding at home in the late clamped group which did reach statistical significance. Overall the trial provides no clear evidence for the benefit of early cord clamping (the current policy as part of the active management of the third stage in the UK) on the outcomes considered.  相似文献   
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1It has been suggested that lipophilic HMG CoA reductase inhibitors, like lovastatin and simvastatin, may cause sleep disturbance. 2Six hundred and twenty-one patients at increased risk of coronary heart disease were randomized in a single centre to receive 40 mg daily simvastatin, 20 mg daily simvastatin or matching placebo. To assess the effects of prolonged use of simvastatin on nocturnal sleep quality and duration, a sleep questionnaire was administered to 567 patients (95% of 595 survivors) at an average of 88 weeks (range: 44–129 weeks) after randomization. 3The main outcome measures were sleep-related problems and use of sleep-enhancing medications reported during routine study follow-up visits, and responses to the sleep questionnaire about changes in sleep duration and about various sleep events during the preceding month. 4No differences were observed between the treatment groups in the frequency of sleep-related problems reported, in the proportion of follow-up visits at which such problems were reported, or in the use of sleep-enhancing medications. The numbers who stopped study treatment were similar in the different treatment groups, and no patient stopped principally because of insomnia. In response to the sleep questionnaire, there were no significant differences between the treatment groups in reports of various sleep events during the preceding month, except that slightly fewer patients allocated simvastatin reported waking often. No differences in sleep duration were observed. 5This placebo-controlled trial does not indicate any adverse effects of prolonged treatment with simvastatin on systematically sought measures of sleep disturbance.  相似文献   
3.
Forty nine of the 149 boys (33%) at a preparatory school fell ill at the beginning of the autumn term 1986 with symptoms of influenza. One hundred and eighty two of the 470 pupils (39%) in the senior part of the same school had similar symptoms of influenza at the beginning of the spring term 1987. A new variant of influenza A H1N1 virus was isolated from both outbreaks and shown to be antigenically similar to A/Taiwan/1/86. The attack rate among pupils who had previously received trivalent influenza vaccine containing A/Chile/1/83 H1N1 antigen was not significantly different from the rate among those who had never been vaccinated. It is concluded that annual vaccination of all boarding school pupils may be inappropriate.  相似文献   
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Eighteen influenza A (H3N2) viruses were isolated during a single outbreak in a closed community of Carmelite nuns. Serological analysis of the virus haemagglutinin (HAs), using a panel of monoclonal antibodies, demonstrated antigenic microheterogeneity. In contrast, no significant biochemical differences were detected in viral genes by RNA:RNA hybridisation or in structural or nonstructural polypeptides analysed by high-resolution polyacrylamide gel electrophoresis (PAGE) or by limited proteolysis followed by PAGE. Influenza A (H3N2) viruses isolated in the vicinity of the convent were distinguishable from each other and from the epidemic viruses isolated in the convent both antigenically and biochemically.  相似文献   
7.
Summary An influenza B virus was passaged in man (virus A) and then in human embryo trachea (C) and into embryonated eggs (D) or directly into eggs (B). Virus A, B, and C had the same (cell-like) haemagglutinin phenotype on reaction with selected monoclonal antibodies while D had an egg-like phenotype. The viruses were administered at a dose of 1,000 TCD50 (for MDCK cells) by intranasal inoculation to groups of 27 or 28 volunteers. Viruses A, B, and C all produced disease in six to eight volunteers, whereas D produced no illness and only four volunteers were infected. The viruses shed by the volunteers were indistinguishable from those with which they were inoculated. The haemagglutinin genes of the viruses were sequenced and changes were detected indicating amino acid substitutions at position 196–198 in the attenuated egg-grown virus D whereby a potential glycosylation site present in the other viruses was lost.  相似文献   
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The Oxford Cholesterol Study is a randomized placebo-controlledtrial designed primarily to assess the effects of simvastatinon blood cholesterol levels and side-effects in preparationfor a large, long-term trial of the effects of cholesterol-loweringdrug therapy on mortality. At present there is only limitedevidence from randomized comparisons of the effects of HMG-CoAreductase inhibitors, such as simvastatin, on thrombogenic,as distinct from atherogenic, pathways in coronary heart disease.The present sub-study was carried out to assess the effectsof simvastatin on a range of haemostatic variables, as wellas on free fatty acids and on lipoprotein fractions not studiedin detail previously. At an average of about 2 years after starting study treatment,non-fasting blood samples were obtained from a sequential sampleof 162 participants who had been randomly allocated to receive40 mg (54 patients) or 20 mg (57 patients) daily simvastatinor matching placebo treatment (51 patients). Only patients whoreported taking their study treatment and who were not knownto be diabetic or to be taking some other lipid lowering treatmentwere to be included. The principal comparisons were to be ofthose allocated simvastatin (i.e. 20 and 40 mg doses combined)vs those allocated placebo. Among patients allocated simvastatin, marginally significantlower factor VII antigen levels (12·10%±6·08of standard; 2P<0·05) and non-significantly lowerfactor VII coagulant activity (8·24%±4·99of standard) and fibrinogen concentrations (0·10±0·08g.l–1) were observed. In contrast, plasminogen activatorinhibitor activity was significantly higher (2·62±1·03IU; 2P<0·01) among patients allocated simvastatin.No significant differences were seen in the other haemostaticfactors studied (e.g. prothrombin fragment 1·2, factorXII and C$$$ inhibitor). Total free fatty acid concentrationwas marginally significantly reduced (2P=0·02) with simvastatin,but none of the reductions in individual free fatty acids wassignificant. Lipoprotein fractions were only measured amongpatients allocated 40 mg daily simvastatin or placebo. Comparedwith placebo, simvastatin produced significant decreases notonly in LDL cholesterol (1·74±0·15 mmol.1–1;2P<0·0001) but also in VLDL cholesterol (0·28±0·08mmol.1–1; 2P<0·001) and IDL cholesterol (0·17±0·03mmol.1–1; 2P<0·0001). There were also lowertriglyceride levels associated with LDL (0·07±0·01mmol.1–1; 2P<0·0001), IDL (0·03±0·01mmol.1–1; 2P<0·01) and VLDL (0·27±0·14;2P=0·05). The effects of simvastatin on haemostatic variables appear tobe far less marked than its lipid effects. Given the associationsof haemostatic factors with coronary heart disease incidence,larger randomized comparisons of the HMG-CoA re1ductase inhibitors(and of the newer fibrates, which may produce greater effects)are needed to provide more reliable estimates of the extentto which they influence these variables.  相似文献   
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