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31.
Elevated concentrations of intracellular calcium ([Ca]i) have been implicated as an important signalling event during attaching and effacing (A/E) lesion formation by enteropathogenic Escherichia coli (EPEC). The highly localized nature of the cytoskeletal and cell surface alterations occurring during A/E lesion formation suggests that there should be equally localized EPEC-induced signalling events. To analyze further the calcium responses to infection of HEp-2 cells by EPEC, we employed calcium-imaging fluorescence microscopy, which allows both temporal and spatial measurements of [Ca]i in live cells. Using this imaging technique, not only were we unable to detect any significant elevation in [Ca]i at sites of A/E EPEC adhesion, but, with several different classical EPEC and enterohemorrhagic E. coli (EHEC) strains and three different infection procedures, each of which resulted in extensive A/E bacterial adhesion, we were unable to detect any significant alterations in [Ca]i in infected cells compared to uninfected cells. In addition, chelation of intracellular free calcium with bis-(aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA) did not, as previously reported, prevent A/E lesion formation. We conclude that increased [Ca]i are not required for A/E lesion formation by EPEC and EHEC.  相似文献   
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Health care executives across the country, faced with intense competition, are being forced to consider drastic cost cutting measures as a matter of survival. The entire health care industry is under siege from boards of directors, management and others who encourage health care systems to take actions ranging from strategic acquisitions and mergers to simple "downsizing" or "rightsizing," to improve their perceived competitive positions in terms of costs, revenues and market share. In some cases, management is poorly prepared to work within this new competitive paradigm and turns to consultants who promise that following their methodologies can result in competitive advantage. One favored methodology is reengineering. Frequently, cost cutting attention is focused on the materials management budget because it is relatively large and is viewed as being comprised mostly of controllable expenses. Also, materials management is seldom considered a core competency for the health care system and the organization performing these activities does not occupy a strongly defensible position. This paper focuses on the application of a reengineering methodology to healthcare materials management.  相似文献   
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Necrotizing enterocolitis (NEC) and midgut volvulus (MGV) often are associated with extensive bowel necrosis. These cases may require extensive enterectomy and the formation of high or multiple stomas, and frequently are complicated by short bowel syndrome, excessive fluid losses, fistulas, stenosis, and skin breakdown. This report describes a "clip and drop-back" technique, followed by delayed anastomosis performed 48 to 72 hours later. The technique was successful in five severely ill infants (3 NEC, 2 MGV) with extensive necrosis, bowel perforation(s), and peritonitis, who required either a high stoma near the ligament of Treitz or multiple resections and enterostomies. This method removes obvious necrotic perforated bowel, controls contamination, avoids stomas (and their inherent complications in this age group), and preserves bowel length. All five babies survived. The technique is a useful addition to the pediatric surgeon's operative armamentarium in selective cases.  相似文献   
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Mean MMPI profiles of 40 Indian and 40 White veterans were similar, but "Indianism," as measured by the Indian Culturalization Test, was significantly related to scores on Hs, Hy, Pt and Sc scales. Caution is advised in using the MMPI in the diagnosis of Indians' psychiatric problems.  相似文献   
35.
A cardiac transplant recipient with multiple coronary artery fistulae draining into the right ventricle is described. These fistulae presumably resulted from repeated endomyocardial biopsies. The diagnosis of coronary artery fistulae was made at the annual coronary arteriography. The magnitude of the shunt remained small over eight years of follow-up.  相似文献   
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BACKGROUND: Auxiliary liver transplantation has several advantages over standard orthotopic liver transplantation. However, functional competition has been reported even in auxiliary partial orthotopic liver transplantation (APOLT). We evaluated herein the interaction in APOLT between the native liver and the graft in terms of portal blood flow and regeneration. The need for diversion of the portal blood flow to the graft was also assessed. METHODS: A total of 15 patients received APOLT from living donors. Portal blood flow to the native liver was preserved in 6 patients, and the portal vein to the native liver was preemptively transected at the time of transplantation in 9 patients. RESULTS: Of the patients with preservation of the portal blood flow to the native liver, two showed inadequate graft portal blood flow just after operation, and in the other three patients the graft portal blood flow decreased or the graft atrophied after deterioration of the graft function. In the patients with preemptive transection of the portal vein to the native liver, optimal graft portal blood flow was obtained, and the native liver, supplied only by arterial inflow, supported a small-for-size graft until the graft regenerated. The damage to the native liver was minimal. CONCLUSIONS: Functional competition may occur in APOLT with preservation of the portal blood flow to the native liver, whereas preemptive transection of the native liver portal vein is a safe procedure and effectively prevents the portal steal phenomenon.  相似文献   
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OBJECTIVES: Little information is available about the intake of very-long-chain n-3 fatty acids in random samples of populations. We examined if the intake of these fatty acids was associated with gender, social status and lifestyle in a similar way as other indicators for a healthy diet in a nationwide survey. DESIGN AND SUBJECTS: Data were obtained from self-administered quantitative food frequency questionnaires filled in by a representative sample of Norwegian men and women, aged 16-79 y. 3144 (63%) of the invited subjects responded with acceptable questionnaires. RESULTS: Daily intake of very-long-chain n-3 fatty acids was on average 0.9 g/d and 0.4% of total energy was derived from these fatty acids. Energy derived from very-long-chain n-3 fatty acids was slightly higher among men than women, and two-fold higher among subjects aged 60-79 vs 16-29 y. White collar workers had higher intake of very-long-chain n-3 fatty acids than blue collar workers. Men and women in the highest quartile of intake of very-long-chain n-3 fatty acids had 2-3 E% higher fat intake (mostly mono- and polyunsaturated fatty acids), as compared to individuals in the lowest quartile. They also had 3-4 fold higher daily intake of retinol and vitamin D, as well as 20-50% higher intake of fruits and vegetables, dietary fibre and vitamin C. CONCLUSIONS: Intake of very-long-chain n-3 fatty acids was correlated to indicators for healthy dietary habits. However, contrary to many other indicators of a healthy diet, energy derived from very-long-chain n-3 fatty acids was not significantly associated with female gender or non-smoking.  相似文献   
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