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Menopause is presumed to have a causative role in the development of female urinary incontinence. While some clinical trials have shown that estrogen can affect urinary tract function, our knowledge of the pathophysiologic changes resulting from menopause and hormone replacement therapy is poor. The cynomolgus monkey is a well-established model for study of menopause and hormone replacement therapy, particularly in the cardiovascular arena. We have utilized this animal model to determine the histologic effects of estrogen and estrogen/progestin replacement therapy in the proximal urethra and vagina. Estrogen and estrogen/progestin replacement induced an increase in the amount of vaginal but not urethral epithelium. Hormone replacement also resulted in a significant increase in the loose, vascular component of the connective tissue layer of the urethra. The cynomolgus macaque shows promise as a useful model for further study of the effects of hormone replacement on the lower urinary tract. © 1996 Wiley-Liss, Inc.  相似文献   
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In order to analyse immune-stimulatory effects of infection of human tumor cells with Newcastle Disease Virus (NDV), gamma-irradiated human breast carcinoma, colon-carcinoma or glioblastoma cells from defined cell lines were modified either by true infection with live virus or by cell surface adsorption of UV-inactivated replication deficient virus. Modification with live but not inactive NDV induced in all human tumor cells IFN-beta and the chemokines RANTES and IFN-gamma-inducible protein-10 (IP-10). In addition, infection by live NDV induced upregulation of HLA-ABC-molecules in all tumor lines tested and HLA-DR molecules in breast carcinoma lines. Two cell adhesion molecules, ICAM-I (CD54) and LFA-3 (CD58), were also upregulated on human tumor cells after infection with live NDV. When infection of MCF-7 breast carcinoma cells by NDV was performed in the presence of neutralizing anti-IFN-beta antibodies no upregulation of HLA molecules was observed suggesting an important role of IFN-beta in this process. Forty-eight to 72 hours after infection of the irradiated tumor cells with live NDV, many tumor cells were dead or in early or late stages of apoptosis. These results provide explanations for the function of the virus-modified autologous tumor vaccine ATV-NDV with which promising clinical results have already been obtained.  相似文献   
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This paper focuses on the question of sampling (or selection of cases) in qualitative research. Although the literature includes some very useful discussions of qualitative sampling strategies, the question of sampling often seems to receive less attention in methodological discussion than questions of how data is collected or is analysed. Decisions about sampling are likely to be important in many qualitative studies (although it may not be an issue in some research). There are varying accounts of the principles applicable to sampling or case selection. Those who espouse 'theoretical sampling', based on a 'grounded theory' approach, are in some ways opposed to those who promote forms of 'purposive sampling' suitable for research informed by an existing body of social theory. Diversity also results from the many different methods for drawing purposive samples which are applicable to qualitative research. We explore the value of a framework suggested by Miles and Huberman [Miles, M., Huberman,, A., 1994. Qualitative Data Analysis, Sage, London.], to evaluate the sampling strategies employed in three examples of research by the authors. Our examples comprise three studies which respectively involve selection of: 'healing places'; rural places which incorporated national anti-malarial policies; young male interviewees, identified as either chronically ill or disabled. The examples are used to show how in these three studies the (sometimes conflicting) requirements of the different criteria were resolved, as well as the potential and constraints placed on the research by the selection decisions which were made. We also consider how far the criteria Miles and Huberman suggest seem helpful for planning 'sample' selection in qualitative research.  相似文献   
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Summary Forty three patients, admitted to the department of Neurological Surgery for management of central nervous system tumours, were studied pre-operatively for serum myelin basic protein immunoreactivity as a marker of central nervous system lesion and for circulating immunoglobulins and complement (C3) levels. Myelin basic protein concentration did not appear to correlate with tumour type or grade. Serum immunoglobulin levels were found to be within the normal range but the mean IgM level was significantly higher in the glioma group when compared with meningiomas.  相似文献   
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