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Upper abdominal surgery has a high incidence of postoperative respiratory complications. Although operations involving a thoracic as well as an upper abdominal incision as encountered in esophageal surgery are likely to be associated with an even higher complication rate and perhaps permanent alterations of respiratory function, only a few studies have addressed this problem. We evaluated the postoperative course of patients undergoing thoracoabdominal esophagectomy with esophagogastrostomy. Twenty patients were evaluated, of whom 10 (50%) developed respiratory complications as defined by our criteria, which were the simultaneous occurrence of rectal temperature over 38 degrees C on the first postoperative day and radiographic evidence of pulmonary infiltration. Although there is no general consensus regarding the diagnostic criteria of a postoperative pulmonary complication, we were able to validate the clinical relevance of our definition by showing that these patients suffered from a more severe and more prolonged impairment of global oxygen exchange than those who did not fulfill the criteria. They also required a longer period of respiratory support (median duration of intubation 12 vs. 3 days, P less than 0.005). A comparison of the preoperative pulmonary function with that determined at least 6 months after the operation showed that only vital capacity (VC) and total lung capacity (TLC) were significantly (P less than 0.05) reduced following the operation, but not to a clinically relevant degree (VC-6%, TLC-7%).  相似文献   
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In the early 1990s, breast cancer activists in the United States challenged the scientific establishment to include lay activists in the inner circles of science policy making. Within a few years, activists' demands extended beyond policy to inclusion in the everyday practices of science, that is, in the formulation of research questions, the design of scientific studies and the review of scientific grant proposals. While some activists refer to themselves as consumers, their participation in the practices of science has taken them beyond the narrow framework of consumption and cast them as producers, rather than simply consumers, of scientific knowledge. This paper describes a science education program organized by breast cancer activists to prepare them for involvement in the scientific arena. The specific goals of this educational program are to teach basic concepts of biology and epidemiology and critical appraisal of scientific literature and research studies, as well as to examine the institutional practices of science. By simultaneously engaging with the content and the politics of science in Project LEAD, breast cancer activists acquire tools that allow them not only to influence science policy but to evaluate the truth claims of science. In the process, they take a more active and direct role in determining the nature of knowledge produced about breast cancer.  相似文献   
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Objective. To determine in a prospective study the normal MRI morphology of the sacroiliac joints (SIJs) in relation to age and sex during adolescence. Design and patients. A total of 98 children (63 boys, mean age 12.7±2.8 years; 35 girls, mean age 13.7±2.3 years), ranging in age from 8 to 17 years, with juvenile chronic arthritis (JCA) but without signs of sacroiliitis fulfilled the study prerequisites (no back pain and no pathologic changes of the SIJs on physical examination before MRI in a 1.5-year follow-up). An additional eight HLA-B27-negative boys and eight HLA-B27-negative girls without arthritis served as controls. The MRI protocol comprised a T1-weighted SE sequence, an opposed-phase T2*-weighted GE sequence, and a dynamic contrast-enhanced study in single-section technique. Results. Noncontrast MRI permitted differentiation of “open” from ossified segmental and lateral apophyses of the sacral wings, with a significant difference in age (P <0.05) between children with open and ossified apophyses. Ossification of the apophyses of the sacral wings was seen significantly earlier (P <0.05) in girls than in boys. Girls also had a significantly higher incidence of transitional lumbosacral vertebrae, pelvic asymmetries, and accessory joints. In the contrast-enhanced opposed-phase MRI study, normal cartilage of the SIJs showed no contrast enhancement whereas the joint capsule showed a moderate enhancement. Conclusion. There are significant age- and sex-related differences in the normal MRI morphology of juvenile SIJs. Our findings might serve as a standard of comparison for the evaluation of pathologic changes – in particular for the early identification of juvenile sacroiliitis.  相似文献   
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