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Pharmacokinetic profiles were obtained for 16 heart or lung recipients following the administration of identical doses of cyclosporin as oral solution and capsules on consecutive days. A comparison of pharmacokinetic parameters (AUC, Cmax, Cmin and tmax) showed that there were no significant differences between the two formulations except for the tmax, which was significantly longer for the capsules. The mean variation in day-to-day trough levels produced by the two different forms was 25.6%. A retrospective study was carried out of consecutive cyclosporin levels in patients at steady state on oral solution. The mean variation in day-to-day trough levels was 32.3%. This was not significantly different from the variation in consecutive trough levels seen in the oral solution/capsule comparison. This study shows that cyclosporin capsules can be substituted for oral solution without causing acute changes in cyclosporin blood levels, and that the pharmacokinetics of the two formulations are similar.This work was carried out in partial fulfillment of the requirements for the Master of Science Degree in Clinical Pharmacy, University of London  相似文献   
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OBJECTIVES: To evaluate the sensitivity to change of the Endometriosis Health Profile-30 (EHP-30) questionnaire. SETTING: The Women's Center, John Radcliffe Hospital, Oxford. DESIGN: Postal survey to 66 women undergoing conservative surgery for the treatment of endometriosis-associated pain. The EHP-30 and the Short Form-36 (SF-36) were administered 2 weeks before the operation, and 4 months post-operatively. At T2 a transition question was included to evaluate changes in patients health status. To evaluate responsiveness effect sizes, standardised response means, the index of responsiveness and the minimally and clinically important differences were calculated. RESULTS: Forty (66.6%) patients returned the questionnaires at time 1 and 2. Overall less responsive effect size scores were found for the SF-36 (0.1-0.5) compared to the EHP-30 (-0.1-1.1) for all patients who had undergone treatment. Minimally important differences and the index of responsiveness were overall higher for the EHP-30 (0.4-2.0) compared to the SF-36 (0.1-1.0). Change scores for four of the five scales were significantly correlated with women's responses to the transition question. CONCLUSIONS: Results suggest that the EHP-30 is sensitive to change. Its application in clinical trials should prove beneficial in assessing the impact of medical and surgical interventions upon quality of life for women with endometriosis.  相似文献   
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This article analyzes hidden status among crack, powder cocaine, and heroin users and setters, in contrast to more accessible users/sellers. Several sampling strategies acquired 657 users (N=559) and sellers (N=98). Indicators of hidden status were those who (1) paid rent in full in the last 30 days, (2) used nonstreet drug procurement. (3) had legal jobs, and (4) earned $1,000 or more in legal income in the last 30 days. Nearly half had at least one indicator: approximately 16% of users/sellers had two to four indicators. In logistic regression analyses, those who had not panhandled in the last 30 days, those who had used powder cocaine in the last 30 days, and those never arrested were the most likely to have hidden status, whether the analysis predicted those having any indicators or those having two to four indicators. The four indicators begin to operationally define hidden status among users of cocaine and heroin.  相似文献   
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A framework for evaluating image segmentation algorithms.   总被引:4,自引:0,他引:4  
The purpose of this paper is to describe a framework for evaluating image segmentation algorithms. Image segmentation consists of object recognition and delineation. For evaluating segmentation methods, three factors-precision (reliability), accuracy (validity), and efficiency (viability)-need to be considered for both recognition and delineation. To assess precision, we need to choose a figure of merit, repeat segmentation considering all sources of variation, and determine variations in figure of merit via statistical analysis. It is impossible usually to establish true segmentation. Hence, to assess accuracy, we need to choose a surrogate of true segmentation and proceed as for precision. In determining accuracy, it may be important to consider different 'landmark' areas of the structure to be segmented depending on the application. To assess efficiency, both the computational and the user time required for algorithm training and for algorithm execution should be measured and analyzed. Precision, accuracy, and efficiency factors have an influence on one another. It is difficult to improve one factor without affecting others. Segmentation methods must be compared based on all three factors, as illustrated in an example wherein two methods are compared in a particular application domain. The weight given to each factor depends on application.  相似文献   
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