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91.
92.
A postal survey of 434 clinicians at four local hospitals was undertaken in order to identify the methods by which clinicians learn how to request permission for hospital autopsies and to assess the preferred techniques and timing of relevant communication skills training. The majority of 128 responding clinicians had learnt through personal experience with some assistance from senior colleagues and peers. Few clinicians appeared to have learnt through formal training. The preferred methods for the provision of communication skills training were training in small groups (such as seminars or tutorials) and observation of clinicians at work. The most desirable time for the provision of this training was considered to be between the beginning of the final undergraduate year and the end of the pre-registration house officer year. The communication skills training provided within medical education is in need of improvement. More emphasis should be given to clinical-task- or situation-specific applications such as requesting permission for autopsies. 相似文献
93.
T cell responses to orbital antigens in thyroid-associated ophthalmopathy. 总被引:3,自引:1,他引:2 下载免费PDF全文
K Arnold N Tandon R S McIntosh R Elisei M Ludgate A P Weetman 《Clinical and experimental immunology》1994,96(2):329-334
Thyroid-associated ophthalmopathy (TAO) is most likely to be a T cell-mediated disease, in which cytokines released in the extraocular muscles activate fibroblasts, increasing glycosaminoglycan production. The nature of the orbital antigen recognized by the infiltrating T cells is unclear, although it is possible that there is cross-reactivity between this and a thyroid autoantigen to explain the close association with thyroid autoimmunity. We have tested the ability of human and porcine eye muscle antigen preparations to stimulate proliferation of circulating T cells from healthy subjects and patients with TAO or Graves' disease without clinical TAO. Occasional responses were seen, particularly after depletion of CD8+ T cells, and two out of 10 TAO patients responded to eye muscle proteins of 25-50 kD after fractionation of antigens on gels and subsequent elution. There was no disease-specific response of T cells to R1, R14, D1 and 1D3, recombinant proteins identified from screening an eye muscle cDNA library with sera from patients with autoimmune thyroid disease. We have also found that interferon-gamma (IFN-gamma) production by T cells from TAO patients was not stimulated by eye muscle membrane antigens or by 1D3. These results suggest that the frequency of circulating T cells responding to eye muscle antigens in TAO is low, and that several candidate orbital antigens, including the 64-kD protein 1D3, are unlikely to be important T cell autoantigens in this condition. 相似文献
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95.
BACKGROUND: Statistical power is a measure of the extent to which a study
is capable of discerning differences or associations which exist within the
population under investigation, and is of critical importance whenever a
hypothesis is tested by statistics. Conventionally, studies should reach a
power level of 0.8, such that four times out of five a false null
hypothesis will be rejected by a study. Statistical power may most easily
be increased by increasing sample size. OBJECTIVE: We aimed to assess the
level of statistical power of general practice research. METHODS: A total
of 1422 statistical tests in 85 quantitative original papers in the British
Journal of General Practice were analysed for statistical power. RESULTS:
The median power of tests analysed was 0.71, representing a slightly
greater than two-thirds likelihood of rejecting false null hypotheses. Of
85 studies, 37 (44%) attained power of 0.8 or more. Ten studies had power
of more than 0.99 suggesting 'over-powering'. Twenty- one of the papers
surveyed (25%) had a likelihood of gaining significant results poorer than
that obtained by tossing a coin when a null hypothesis is false.
CONCLUSION: While achieving higher power than studies in similar surveys of
other disciplines, the power of general practice research falls short of
the 0.8 convention. Adequate power is essential so that effects which exist
are not missed. Recommendations are made concerning power calculations
prior to the start of research and reporting of results in journal
articles.
相似文献
96.
97.
Efforts to understand the processes of change in psychotherapy have typically been based on either clinicians' experiences or on empirical studies somewhat removed from the day-to-day work and concerns of psychotherapists. This paper reviews selected examples of insights and issues derived from each of these sources. It is suggested that our understanding of change processes in psychotherapy will be enhanced by the growing convergence between the two approaches. 相似文献
98.
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