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191.
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The effect of preoperative chemotherapy in the treatment of esophageal carcinoma is difficult to assess because of the inadequacies of clinical staging. Endoscopic esophageal ultrasound (EUS) has been shown to be accurate in the clinical determination of depth of tumor invasion (T) and regional lymph node status (N). Therefore, EUS may be useful in assessing the effect of preoperative chemotherapy in the treatment of esophageal carcinoma. Eleven patients with operable adenocarcinoma of the esophagus or esophagogastric junction underwent staging by EUS before treatment. This was followed by two courses (10 patients) or one course (1 patient) of chemotherapy: etoposide, 120 mg/m2 for 3 days; doxorubicin hydrochloride, 20 mg/m2; and cisplatin, 100 mg/m2. Restaging by EUS was done after treatment. Ten patients then underwent resection of the tumor with lymphadenectomy. One patient was found to have metastatic disease at thoracotomy and did not undergo resection. However, tissue sampling was adequate for the determination of pathological stage. Independent pathological determinations of T and N were then obtained. On completion of chemotherapy, 9 patients (82%) had relief or reduction of preoperative symptoms, and 9 patients (82%) had either no evidence of tumor or reduction of tumor size by endoscopy. Despite this clinical and endoscopic response, no patient had EUS-documented and pathology-confirmed reduction of T. However, 2 patients had EUS-documented and pathology-confirmed progression of N. The accuracy of EUS in the determination of T was 82% and of N, 73%.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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We report the first case of lethal autosomal recessive osteopetrosis in mice caused by a spontaneous 8-bp deletion in exon 2 of the Rank gene. The phenotype, including a block in RANKL-dependent osteoclast differentiation and lymph node agenesis, copies that of Rank(-/-) mice, which have been produced by targeted recombination. INTRODUCTION: Commitment of osteoclast progenitors to the osteoclast lineage requires RANKL/RANK-mediated intercellular signals. Gene-targeted defects in this signaling pathway resulted in osteoclast deficiency and severe osteopetrosis in mice, but to date, there have been no reports of spontaneous mutations in Rankl or Rank resulting in osteopetrosis. MATERIALS AND METHODS: Mice with malignant osteopetrosis and absent lymph nodes appeared spontaneously in a highly inbred colony. Appropriate crosses were analyzed to establish the pattern of inheritance. Tissues from affected pups and littermates were evaluated grossly, histopathologically, and radiographically. Osteoclast development from splenocytes was tested in vitro under a variety of conditions, including after infection with RANK-encoding retrovirus. Rank mutational analysis was performed by direct sequencing of RT-PCR products and genomic DNA. RESULTS: The inheritance pattern was consistent with autosomal recessive inheritance, and the phenotype resembled that of either Rankl or Rank knockout mice with the exception of as yet unexplained death of most mice 2-3 weeks after weaning. Osteoclast precursors from the spleens of affected pups failed to form osteoclasts in vitro when stimulated with macrophage-colony stimulating factor (M-CSF) and RANKL, unless they were forced to express wildtype Rank cDNA. Molecular genetic studies identified an 8-bp deletion in exon 2 of the Rank gene. The resulting allele, termed Rank(del8), encodes only a small portion of the RANK extracellular domain, which is probably nonfunctional. CONCLUSIONS: The phenotypic similarities between Rank(del8) and mice previously described with a combined insertion and deletion in Rank confirm the role of this receptor in osteoclastogenesis and lymph node development and suggest that some forms of malignant osteopetrosis in humans could result from a similar defect.  相似文献   
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Biologic mechanisms by which skin grafts become revascularized after transplantation are poorly understood. To investigate graft revascularization, we examined the pattern of capillary growth in full-thickness skin grafts at serial time points. Full-thickness skin (2 x 2 cm) was excised to muscle fascia from the bilateral hind limbs of adult male Lewis rats. The graft/wound base boundary was identified by placement of a polypropylene mesh on the wound beneath the graft. Excised skin was replaced in its original orientation and secured with silk sutures tied over a gauze bolster dressing. After 3, 5, 7, and 10 days, animals were killed, and their aortas were cannulated and infused with an acrylic polymer to generate vascular casts. Grafts were excised, tissues were digested, and casts were examined with the use of scanning electron microscopy. Transmission electron microscopy was performed on tissues infused with the acrylic polymer that were not digested. At day 3, an immature lobular pattern was observed extending from the neovascular plexi on the graft side of the polypropylene mesh. At day 5, defined vessels with lobular ends occurred with high frequency. At day 7, the number of observed lobular structures was greatly reduced, and high frequencies of depressions in acrylic casts suggested protrusion of endothelial cell nuclei. By day 10, lobular structures were rare, well-defined microvascular plexi were contiguous with larger vessels, and depressions from endothelial cell nuclei appeared more shallow and less frequent. These findings suggest that (1) an immature lobular pattern representing either capillary outgrowth or extracapillary leakage occurs at day 3; (2) these immature lobules decrease, and more discrete capillaries increase by day 5; (3) vascular integrity is reestablished by day 7; (4) vascular plexi has regained full continuity, and there are suggestions that endothelial cell proliferation has subsided by day 10.  相似文献   
196.
OBJECTIVE: Comparison of cultured skin substitutes (CSS) and split-thickness skin autograft (AG) was performed to assess whether donor-site harvesting can be reduced quantitatively and whether functional and cosmetic outcome is similar qualitatively in the treatment of patients with massive cutaneous burns. SUMMARY BACKGROUND DATA: Cultured skin substitutes consisting of collagen-glycosaminoglycan substrates populated with autologous fibroblasts and keratinocytes have been shown to close full-thickness skin wounds in preclinical and clinical studies with acceptable functional and cosmetic results. METHODS: Qualitative outcome was compared between CSS and AG in 45 patients on an ordinal scale (0, worst; 10, best) with primary analyses at postoperative day 28 and after about 1 year for erythema, pigmentation, pliability, raised scar, epithelial blistering, and surface texture. In the latest 12 of the 45 patients, tracings were performed of donor skin biopsies and wounds treated with CSS at postoperative days 14 and 28 to calculate percentage engraftment, the ratio of closed wound:donor skin areas, and the percentage of total body surface area closed with CSS. RESULTS: Measures of qualitative outcome of CSS or AG were not different statistically at 1 year after grafting. Engraftment at postoperative day 14 exceeded 75% in the 12 patients evaluated. The ratio of closed wound:donor skin areas for CSS at postoperative day 28 was significantly greater than for conventional 4:1 meshed autografts. The percentage of total body surface area closed with CSS at postoperative day 28 was significantly less than with AG. CONCLUSIONS: The requirement for harvesting of donor skin for CSS was less than for conventional skin autografts. These results suggest that acute-phase recovery of patients with extensive burns is facilitated and that complications are reduced by the use of CSS together with conventional skin grafting.  相似文献   
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The present study explored the multiple identities held by health professionals in a large public hospital that was experiencing organizational change that involved the transition from the traditional use of professional hierarchies to the use of new clinical teams. Consistent with predictions from social identity theory and research, the results of an organization-wide survey (N = 615) reveal the protective role of identification with professional departments during change that threatened group status. Professional departments were the preferred target of identification of employees, and employees who preferred this target reported a stronger sense of identification. Also consistent with our predictions, employees who were members of higher status groups reported greater job satisfaction, higher levels of openness to organizational change, and reduced levels of change-related uncertainty. These results were more pronounced for employees who identified with their professional department. Implications for managing multiple identities during organizational transition are discussed.  相似文献   
200.
Hand hygiene is a core element of patient safety for the prevention of healthcare-associated infections and the spread of antimicrobial resistance. Its promotion represents a challenge that requires a multi-modal strategy using a clear, robust and simple conceptual framework. The World Health Organization First Global Patient Safety Challenge 'Clean Care is Safer Care' has expanded educational and promotional tools developed initially for the Swiss national hand hygiene campaign for worldwide use. Development methodology involved a user-centred design approach incorporating strategies of human factors engineering, cognitive behaviour science and elements of social marketing, followed by an iterative prototype test phase within the target population. This research resulted in a concept called 'My five moments for hand hygiene'. It describes the fundamental reference points for healthcare workers (HCWs) in a time-space framework and designates the moments when hand hygiene is required to effectively interrupt microbial transmission during the care sequence. The concept applies to a wide range of patient care activities and healthcare settings. It proposes a unified vision for trainers, observers and HCWs that should facilitate education, minimize inter-individual variation and resource use, and increase adherence. 'My five moments for hand hygiene' bridges the gap between scientific evidence and daily health practice and provides a solid basis to understand, teach, monitor and report hand hygiene practices.  相似文献   
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