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A mixed‐method study of effects of a therapeutic play intervention for children on parental anxiety and parents' perceptions of the intervention 下载免费PDF全文
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Factitious illness in children is a phenomenon that results in adverse consequences for the child. Munchausen by proxy is a factitious disorder, first described by Meadow (1977), in which a parent induces or creates the appearance of illness in the child. This article highlights the importance of social work skills in the identification and management of this syndrome, and proposes a format for decision making at various points in the process. 相似文献
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Relaxin down-regulates renal fibroblast function and promotes matrix remodelling in vitro. 总被引:1,自引:0,他引:1
Rosemary Masterson Tim D Hewitson Kristen Kelynack Marina Martic Laura Parry Ross Bathgate Ian Darby Gavin Becker 《Nephrology, dialysis, transplantation》2004,19(3):544-552
BACKGROUND: Renal fibroblasts are important effector cells in tubulointerstitial fibrosis, with experimental antifibrotic strategies focusing on the functional down-regulation of these cells. Several experimental models of fibrosis have provided evidence for the effectiveness of the polypeptide hormone relaxin as a potential antifibrotic agent. This study was conducted to further elucidate the antifibrotic mechanisms of relaxin on renal fibroblasts in vitro. METHODS: Rat cortical fibroblasts were obtained from outgrowth culture of renal tissue isolated from kidneys 3 days post-unilateral ureteric obstruction and constituted 100% of cells studied. A relaxin radio-receptor assay was used to establish binding of relaxin to renal fibroblasts in vitro. Functional studies then examined the effects of H2 relaxin (0, 1, 10 and 100 ng/ml) on fibroblast kinetics, expression of alpha-smooth muscle actin (alpha-SMA), total collagen synthesis, collagenase production and collagen-I lattice contraction. CTGF mRNA expression was also measured by northern analysis. RESULTS: H2 relaxin bound with high affinity to rat renal fibroblasts, but receptor numbers were low. Consistent with its previously reported bimodal effect, transforming growth factor (TGF-beta 1) reduced fibroblast proliferation, an effect abrogated by H2 relaxin. Fibroblasts exposed to H2 relaxin (100 ng/ml) for 24 h demonstrated decreased immunostaining for alpha-SMA and reduced alpha-SMA protein expression compared with controls. There was a trend for a relaxin-mediated reduction in total collagen synthesis and alpha 1(I) mRNA expression with large dose-related increases in collagenase protein expression being observed. TGF-beta 1-stimulated collagen-I lattice contraction was significantly inhibited following co-incubation with 100 ng/ml relaxin. Incremental doses of H2 relaxin had no significant effect on CTGF mRNA expression. CONCLUSIONS: The findings of this study suggest that the antifibrotic effects of relaxin involve down-regulation of fibroblast activity, increase in collagenase synthesis and restructuring of collagen-I lattices, which are consistent with its known physiological role of matrix remodelling. Although there appears to be an interaction between TGF-beta 1 and H2 relaxin, this does not appear to involve a reduction in CTGF mRNA expression. 相似文献
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Purpose: Following the widespread adoption of energy-dependent rare earth intensifying screens this study investigates the relevance of two conventions (the 10 kVp and kVp-to-the-4th-power rules) commonly used to calculate the kVp/mAs relationship.Methods: A stepwedge was exposed at standard kVp and mAs setting. The kVp was then increased in increments of 5 kVp, and appropriate mAs values were determined using a densitometer. These values were then compared with approximations from the rules previously mentioned.Results: Wide discrepancies are reported between appropriate and approximated values with the latter overestimating exposure by a factor of two.Discussion: Traditional theorems used to estimate the kVp/mAs relationship should no longer be used in modern imaging departments. Each film screen combination should be evaluated individually to ensure appropriate exposure settings. 相似文献
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Improving the safety of patient care is an issue which affects health systems in both developed and developing countries. To co-ordinate and accelerate improvements in patient safety, the World Health Organization (WHO) has supported the creation of the World Alliance for Patient Safety which was launched in October 2004. The six action areas of the Alliance are Patients for Patient Safety, Taxonomy, Research, Solutions for Patient Safety, Reporting and Learning, and a biennial Global Patient Safety Challenge. The first Challenge covering 2005-2006 was launched in October 2005 under the banner 'Clean Care is Safer Care'. The Challenge addresses health care-associated infection, a major, patient safety problem affecting hundreds of millions of people worldwide. 相似文献
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