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IJ Griffin TJ Cole KA Duncan AS Hollman MDC Donaldson 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(5):544-549
Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty. 相似文献
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The inter-connections between educational, family and social spheres of life are integral to the experiences and outcomes of mature student participation in education. This relationship highlights the need to understand the educational experience in the context of the life of the mature student. Mature nursing students have been shown to experience many difficulties during their course. These problems include childcare, relationship and financial difficulties. What is not well documented are the problems and coping strategies of future nursing students who are undertaking Access to Nursing courses and whether these mirror those found in mature nursing students. This small scale exploratory study investigated the course-related problems and coping strategies of mature students undertaking an access to nursing in a Further Education College. This study is one part of a larger programme of research investigating mature students in nursing. In-depth interviews were conducted on mature students and data were analysed using content analysis methods. Content analysis revealed particular concerns regarding the obstacles faced by mature nursing students. In particular the findings suggested that financial difficulties and re-entry into tertiary education were the prominent concerns for these individuals. The coping mechanisms identified to overcome these problems included; support networks, prioritizing and organising, and positive expectations and attitudes for the future. Understanding how students cope with their difficulties will provide the building block for future intervention strategies designed to minimise problems and increase retention rates. Further longitudinal research is required on the long term and cumulative nature of stress and coping in this group from access to post-qualification. 相似文献
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To investigate the putative role of serotonin (5-HT) in auditory brainstem development, the expression of the 5-HT transporter (5-HTT) was evaluated in the normal mouse brainstem at 6 different postnatal ages. The brains of C3H/HeJ mice at birth (P0) and P1, P8-P9, P13, P21-P22, P35-P36 and P48-P50 were collected and processed immunohistochemically with an antibody raised against the 5-HTT. 5-HTT immunoreactivity (5-HTT-IR) was first observed in P8 mice and was localized to cell bodies in the ventral cochlear nucleus (VCN) and principal nuclei of the superior olivary complex, including the medial nucleus of the trapezoid body. Labeled neurons were found in similar regions in older mice except at P48-50, where labeled neurons were observed in the VCN only. 5-HTT-IR was especially prominent in VCN neurons at P21 and was observed in all of the brains examined at this age. These results indicate that auditory brainstem neurons of the normal inbred mouse express the 5-HTT postnatally. The presence of 5-HTT-IR in neurons located in the VCN indicates a regional expression of the 5-HTT that is related to the ascending auditory pathway. The timing of 5-HTT expression indicates that 5-HT may modulate developmental processes that rely on cochlear input. 相似文献
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Kumana CR Cheung G Lauder IJ Cheung BM 《Journal of cardiovascular pharmacology and therapeutics》2004,9(4):223-225
The possible additive antiplatelet effects of aspirin and clopidogrel have been explored in the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) and Management of Atherothrombosis with Clopidogrel in High Risk Patients (MATCH) studies. To assess the overall absolute beneficial and/or harmful impact of aspirin and clopidogrel combination therapy compared with monotherapy with either drug, we analyzed the results from both trials in terms of number needed to treat per year. Treating between 35 and 204 at-risk patients for 1 year with combination therapy appeared to prevent 1 patient from experiencing an adverse primary cardiovascular outcome; whereas, about 1 in 63 such patients appeared liable to major bleeding during that period. We determined that the evidence to date indicates no overall advantage for combination therapy with anti-platelet drugs in preference to monotherapy. 相似文献
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Meta-analysis of large randomized controlled trials to evaluate the impact of statins on cardiovascular outcomes 下载免费PDF全文
AIMS: Since 2002, there have been five major outcome trials of statins reporting findings from more than 47,000 subjects. As individual trial results differed, we performed a meta-analysis to ascertain the effectiveness and safety of statins overall and in subgroups. The aim of the study was to estimate the effect of statins on major coronary events and strokes, all-cause mortality and noncardiovascular mortality, and in different subgroups. METHODS: PubMed was searched for trials published in English. Randomized placebo-controlled statin trials with an average follow up of at least 3 years and at least 100 major coronary events were included. For each trial, the statin used, number and type of subjects, proportion of women, mean age and follow up, baseline and change in lipid profile, cardiovascular and non-cardiovascular outcomes were recorded. RESULTS: Ten trials involving 79,494 subjects were included in the meta-analysis. Due to heterogeneity, ALLHAT-LLT was excluded from some analyses. Statin therapy reduced major coronary events by 27% (95%CI 23, 30%), stroke by 18% (95%CI 10, 25%) and all-cause mortality by 15% (95%CI 8, 21%). There was a 4% (95%CI -10, 3%) nonsignificant reduction in noncardiovascular mortality. The reduction in major coronary events is independent of gender and presence of hypertension or diabetes. The risk reduction was greater in smokers (P < 0.05). Coronary events were reduced by 23% (95%CI 18, 29%) in pravastatin trials and 29% (95%CI 25, 33%) in five trials using other statins. Pravastatin reduced strokes by 12% (95%CI 1, 21%) whilst other statins reduced strokes by 24% (95%CI 16, 32%) (P = 0.04). CONCLUSIONS: Statins reduce coronary events, strokes and all-cause mortality without increasing noncoronary mortality. The benefits accrue in men and women, hypertensives and normotensives, diabetics and nondiabetics, and particularly in smokers. Pravastatin appears to have less impact on strokes. 相似文献
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Kumana CR Tong MK Li CS Lauder IJ Lee JS Kou M Walley T Haycox A Chan TM 《British journal of clinical pharmacology》2003,56(6):670-678
BACKGROUND: Usage of cyclosporin (the Hong Kong Hospital Authority's single largest item of drug expenditure) continues to increase, mainly due to increasing numbers of renal allograft patients taking it as long-term antirejection therapy. Diltiazem, an antihypertensive agent, interferes with the first pass extraction of oral cyclosporin, thus serving to conserve its dosage. AIMS: In renal transplant patients, to assess whether diltiazem co-treatment could achieve worthwhile dosage conservation of Neoral (a relatively new microemulsified cyclosporin formulation), safely. METHODS: A randomized, placebo-controlled, double-blind clinical trial was undertaken at three local hospitals. Renal transplant recipients receiving Neoral as prophylactic immunosuppression were randomized to two treatment arms. Active treatment consisted of diltiazem tablets 30 or 60 mg twice daily for patients weighing < 60 or >or= 60 kg, respectively. One hundred and ten eligible patients gave their informed consent, and were followed up for at least six months. The mean difference in the dollar cost in the sixth month was the primary outcome. Secondary/ancillary outcomes included changes in cyclosporin dosage and blood level, and untoward clinical events including rejection. Outcomes were evaluated by intention to treat analyses. RESULTS: During weeks 23-26 (sixth month) post randomization, diltiazem co-treatment yielded an estimated average cost saving per patient on drugs of 15%[the 95% confidence interval (CI) of the difference being HK dollars 609 +/- 517 or pound 50 +/- 42], with no apparent excess of untoward or adverse events, complications, hospitalization, outpatient visits, or inferior quality of life. CONCLUSIONS: This diltiazem co-treatment regime applied to the nearly 1800 surviving renal allograft patients followed up in Hospital Authority hospitals could have saved approximately HK dollars 14.3 million ( pound 1.17 million) annually, without adverse sequelae. 相似文献