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21.

Background  

Communication training builds on the assumption that understanding of the concepts related to professional communication facilitates the training. We know little about whether students' knowledge of clinical communication skills is affected by their attendance of communication training courses, or to what degree other elements of the clinical training or curriculum design also play a role. The aim of this study was to determine which elements of the curriculum influence acquisition of knowledge regarding clinical communication skills by medical students.  相似文献   
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BACKGROUND AND PURPOSE: This study aimed at quantifying the breathing variations among lung cancer patients over full courses of fractionated radiotherapy. The intention was to relate these variations to the margins assigned to lung tumours, to account for respiratory motion, in fractionated radiotherapy. MATERIALS AND METHODS: Eleven lung cancer patients were included in the study. The patients' chest wall motions were monitored as a surrogate measure for breathing motion during each fraction of radiotherapy by use of an external optical marker. The exhale level variations were evaluated with respect to exhale points and fraction-baseline, defined for intra- and interfraction variations respectively. The breathing amplitude was evaluated as breathing cycle amplitudes and fraction-max-amplitudes defined for intra- and interfraction breathing, respectively. RESULTS: The breathing variations over a full treatment course, including both intra- and interfraction variations, were 15.2mm (median over the patient population), range 5.5-26.7mm, with the variations in exhale level as the major contributing factor. The median interfraction span in exhale level was 14.8mm, whereas the median fraction-max-amplitude was 6.1mm (median of patient individual SD 1.4). The median intrafraction span in exhale level was 1.6mm, and the median breathing cycle amplitude was 4.0mm (median of patient individual SD 1.4). CONCLUSIONS: The variations in externally measured exhale levels are larger than variations in breathing amplitude. The interfraction variations in exhale level are in general are up to 10 times larger than intrafraction variations. Margins to account for respiratory motion cannot safely be based on one planning session, especially not if relying on measuring external marker motion. Margins for lung tumours should include interfraction variations in breathing.  相似文献   
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OBJECTIVE: To analyse early and late mortality after coronary artery bypass grafting (CABG) in patients with and without left main coronary artery (LMCA) stenosis during the 30-year period 1970-1999. METHODS: A total of 1888 of 10,647 patients (18%) who underwent a first isolated CABG at the Karolinska Hospital in Stockholm, Sweden, during 1970-1999 had significant left main coronary artery stenosis. The Swedish National Cause of Death Register was used to determine mortality up to five years after the operation. RESULTS: The proportion of patients with LMCA stenosis of all CABG patients increased from 7% during the 1970s to 26% in 1999. During 1970-1984 early mortality was 5.8% in patients with LMCA stenosis compared with 1.5% in patients without LMCA stenosis (odds ratio (OR) 3.7 (95% confidence interval (CI) 1.8-7.6)). The corresponding rates during 1995-1999 were 2.0% versus 2.2% (OR 0.8 (95% CI 0.5-1.5)), respectively. The increased risk of early death in patients with LMCA stenosis was neutralised in males during 1985-1994 and in females during 1995-1999. Five-year survival in males was 88% after operations performed during 1994-1999 compared with 82% after CABG performed during 1970-1984. Five-year mortality, exclusive of early deaths, during 1970-1984 was higher in patients with LMCA stenosis (12.8%) than in those without (8.4%) (relative risk 1.7 (95% CI 1.1-2.5)). An increased risk of late mortality in patients with LMCA stenosis was neutralised in males during 1985-1994 and in females during 1995-1999. CONCLUSIONS: During 1970-1999 there was a decrease of early and five-year mortality in patients with LMCA stenosis after CABG despite increase of patient age and risk factors. There were gender differences so that the risk of death in patients with compared with in those without LMCA stenosis was neutralised in males during 1985-1994 and in females during 1994-1999. The continuous decline of mortality during three decades most likely reflects improvement of the peri- and postoperative management of patients undergoing CABG during this period.  相似文献   
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106 unicondylar knee replacement tibial components were retrieved and analyzed for the amount and type of polyethylene wear. Three different designs were retrieved which had essentially the same femorotibial conformity. Each design showed a characteristic failure pattern. The polyethylene of PCA tibial components showed serious delamination after only short durations, as a result of heat pressing. St Georg sledge prostheses showed some delamination after 4 years' duration due to sub-surface cracks which were initiated by fusion defects in the polyethylene; metal backing of the components did not affect delamination of this prosthesis. The Marmor designs showed the least wear, with shiny depressions and surface pitting; no delamination was observed in the Marmor prosthesis. Molecular weight determination by gel permeation chromatography and analysis of crystallinity using Fourier transformation infra-red spectroscopy demonstrated that St George polyethylene had higher molecular weight and crystallinity than Marmor polyethylene. In some of the components investigated, crystallinity and molecular weight of the polyethylene were reduced under the wear track when compared with the unworn polyethylene. Since fusion defects may cause delamination of polyethylene we urge manufacturers to reduce the number of such defects.  相似文献   
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Abstract: The results of an intensive treatment program for patients 16–60 yr of age with de novo acute myeloid leukemia are presented. The patients were given conventional induction treatment with daunorubicin and cytarabine. Patients not entering complete remission (CR) after 1 course of daunorubicin/cytarabine were given 1 course of amsacrine/etoposide/cytarabine. Those entering complete remission received 3 consolidation courses using mitoxantrone, etoposide, amsacrine and cytarabine. One hundred and eighteen patients were enrolled. Complete remission was attained after 1–2 courses in 90 patients (76%). Another 6 patients reached CR after 3–4 induction courses for a total CR rate of 81%. If feasible, patients were offered either allogeneic or unpurged autologous bone marrow transplantation. Twenty-four patients underwent allogeneic bone marrow transplantation; 15 in first remission, 8 in second remission, 1 in early relapse. Thirty patients below 56 yr of age underwent autologous bone marrow transplantation in first remission. The overall probability of survival at 4 yr was 34%, and for patients below 40 yr of age 50%. Leukemia-free survival was 35% for the whole cohort of patients; 52% for patients below 40 yr of age. Patients undergoing allogeneic or autologous bone marrow transplantation in first remission had an overall survival of 86% and 47%, respectively, while the probability of leukemia-free survival in these groups was 87% vs. 40% at 4 yr. The CR rate and long-term results of this intensive treatment program compare favorably with other recent studies using intensive consolidation with allogeneic or autologous bone marrow transplantation or high dose cytarabine.  相似文献   
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This study prospectively evaluated the alveolar content of transbronchial biopsy specimens based on whether or not they floated in formalin. One hundred biopsy specimens were obtained from 18 patients. Specimens with any alveoli were significantly more likely to float (45 of 61, 74%) than those with no alveolar tissue (15 of 39, 39%; p less than 0.001). The majority of diagnostic specimens were obtained in eight patients with sarcoidosis, where 47 biopsies were obtained. Fourteen of 19 specimens (74%) with noncaseating granulomas floated, whereas only 11 of 28 (39%; p less than 0.05) nondiagnostic specimens floated. The results of this study suggest that this simple bedside observation may serve to determine the adequacy of transbronchial biopsy specimens, particularly in sarcoidosis.  相似文献   
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