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BACKGROUND: Although some studies have described rehospitalization after transplantation, few have focused on risk factors and consequences of prolonged hospital stay. Our goal was to determine the causes, risk factors, and outcomes of prolonged rehospitalizations after renal transplantation. PATIENTS AND METHODS: In this retrospective study, 574 randomly selected rehospitalization records of kidney transplant recipients were reviewed from 1994 to 2006. Admissions were divided into group 1, prolonged stay (length of stay >14 days, n=149), and group II, short stay (length of stay 62% of all hospital costs; however, they comprised only 26% of the patients. High-risk kidney transplant recipients for prolonged hospitalizations should be closely observed for infections and graft rejection.  相似文献   
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Introduction

In 2009 the Department of Health instructed McKinsey & Company to provide advice on how commissioners might achieve world class National Health Service productivity. Asymptomatic inguinal hernia repair was identified as a potentially cosmetic procedure, with limited clinical benefit. The Birmingham and Solihull primary care trust cluster introduced a policy of watchful waiting for asymptomatic inguinal hernia, which was implemented across the health economy in December 2010. This retrospective cohort study aimed to examine the effect of a change in clinical commissioning policy concerning elective surgical repair of asymptomatic inguinal hernias.

Methods

A total of 1,032 patients undergoing inguinal hernia repair in the 16 months after the policy change were compared with 978 patients in the 16 months before. The main outcome measure was relative proportion of emergency repair in groups before and after the policy change. Multivariate binary logistic regression was used to adjust the main outcome for age, sex and hernia type.

Results

The period after the policy change was associated with 59% higher odds of emergency repair (3.6% vs 5.5%, adjusted odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.03–2.47). In turn, emergency repair was associated with higher odds of adverse events (4.7% vs 18.5%, adjusted OR: 3.68, 95% CI: 2.04–6.63) and mortality (0.1% vs 5.4%, p<0.001, Fisher’s exact test).

Conclusions

Introduction of a watchful waiting policy for asymptomatic inguinal hernias was associated with a significant increase in need for emergency repair, which was in turn associated with an increased risk of adverse events. Current policies may be placing patients at risk.  相似文献   
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Manganese inhibits oxidative stress damage. The aim of this study was to investigate the protective role of manganese on testis structure and sperm parameters in adult mice exposed to formaldehyde (FA). Twenty adult male NMRI mice were selected and randomly divided into four groups: (i) control; (ii) sham; (iii) ‘FA’‐exposed group; and (iv) ‘FA and manganese chloride’‐exposed group. The FA‐exposed groups received 10 mg kg?1 FA daily for 14 days, and manganese chloride was just injected intraperitoneally 5 mg kg?1 on 2nd weeks. Mice were sacrificed, and spermatozoa were collected from the cauda of the right epididymis and analysed for count, motility, morphology and viability. The other testicular tissues were weighed and prepared for histological examination upon removal. Seminiferous tubules, lumen diameters and epithelium thickness were also measured. The findings revealed that FA significantly reduced the testicular weight, sperm count, motility, viability and normal morphology compared with control group (P ≤ 0.05). In addition, seminiferous tubules atrophied and seminiferous epithelial cells disintegrated in the FA group in comparison with the control group (P ≤ 0.05). However, manganese improved the testicular structure and sperm parameters in FA‐treated mice testes (P ≤ 0.05). According to the results, manganese may improve and protect mice epididymal sperm parameters and testis structure treated with FA respectively.  相似文献   
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To determine whether reactive oxygen molecules could directly and reversibly increase the transfer of albumin across an endothelial barrier, we measured albumin transfer across monolayers of endothelium cultured on micropore filters before and after exposure to xanthine and xanthine oxidase. Xanthine and xanthine oxidase increased endothelial albumin transfer in a dose-dependent fashion. Parallel phase contrast and fluorescence microscopy demonstrated retraction of adjacent cells from one another and disruption of the actin filaments. The oxidant- induced increases in albumin transfer and changes in cell shape were reversed by removing xanthine oxidase and then incubating the monolayers for 3 1/2 hours in tissue culture media enriched with fetal bovine serum. However, incubation in tissue culture media without serum resulted in progressive injury and cell death. Hence, the brief exposure to oxidants initiated a progressive injury process that was reversed by incubation in serum. Because intracellular and extracellular calcium are important determinants of cell shape, and because some oxidized membrane lipids act as calcium ionophores, we asked whether oxidants altered endothelial calcium homeostasis. Xanthine-xanthine oxidase increased release of 45Ca++ from preloaded cells. The calcium antagonist lanthanum chloride prevented xanthine- xanthine oxidase increases in endothelial albumin transfer and prevented the changes in cell shape; chelation of extracellular calcium inhibited lysis of endothelium by xanthine-xanthine oxidase; and the calcium ionophore A23187 increased endothelial albumin transfer and mimicked the oxidant-induced changes in cell shape. Lanthanum chloride inhibited these effects of A23187. These data suggest that oxygen radicals can reversibly increase endothelial permeability to macromolecules, that this is associated with reversible changes in endothelial cell shape and actin filaments, and that the changes in cell shape are related to oxidant-induced changes in endothelial calcium homeostasis.  相似文献   
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Cadmium is a toxic heavy metal element, which probably cause infertility by impairment in spermatogenesis. The present work aimed (i) to study the toxic effect of cadmium on spermatogenesis in rat, as well as (ii) the protective effect of Crocus sativus L. on cadmium‐intoxicated rats. Cadmium chloride was administered intraperitoneally during 16 days at intervals of 48 h between subsequent treatments. Crocus sativus L. was pre‐treated in both of control and cadmium‐injected rats. Animals were sacrificed on day 17 after the first treatment. The left cauda epididymis was removed and immediately immersed into Hank's balanced salt solution for the evaluation of sperm count and viability, and left testis was fixed in 10% formalin for histological evaluation. Following contamination with cadmium, a decrease was observed in the number and viability of cauda epididymis sperm, which were increased by Crocus sativus L. pre‐treatment (P < 0.05). In addition, cadmium decreased both cell proliferation and Johnsen Scores in the seminiferous tubules, which were reversed by Crocus sativus pre‐treatment (P < 0.05). Furthermore, cadmium‐induced decrease in the amount of free serum testosterone as well as an increase in lipid peroxidation activity in the testicular tissue was reversed by Crocus sativus L. (P < 0.05). These findings may support the concept that Crocus sativus L. can improve the cadmium toxicity on spermatogenesis.  相似文献   
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