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51.
BackgroundArthroscopic ankle arthrodesis is gaining in popularity. It has been shown to have a shorter time to union and less morbidity than traditional open procedures. The arthroscopic technique has been mainly used for ankles with minimal deformity. Our aim was to find out whether we could reproduce the good results of arthroscopic ankle arthrodesis in both minimally and markedly deformed ankles.MethodsWe reviewed 62 patients who underwent an arthroscopic ankle arthrodesis for end stage arthritis. The average follow up was 63 months (range 21–92 months). Patients were evaluated subjectively and objectively using the Mazur grading system. 4 patients died before final review and 3 were lost to follow-up leaving 55 patients for evaluation.The pre-operative tibiotalar angle in the coronal plane was between 26° valgus and 24° varus. We divided our patients into 2 groups based on the tibiotalar angle. Group A (n = 31) had a varus or valgus deformity of less than 15? and Group B (n = 24) had a deformity equal to or more than 15°.ResultsThe overall fusion rate was 91%. Fusion occurred in 29 of 31 (94%) ankles in Group A compared to 21 of 24 (88%) in Group B (p = 0.64).The overall mean time to union was 10.4 weeks. The time to union in Group A was 8.8 weeks compared to 12.7 weeks for Group B (p = 0.001). Using the Mazur ankle grading system, 84% of the cases in Group A had a good to excellent result compared to 79% in Group B (p = 0.73). There were 2 superficial infections, 2 cases of deep vein thrombosis and 3 patients required removal of prominent screws.ConclusionsWe have shown that arthroscopic ankle arthrodesis yields reliable and reproducible results in a District General Hospital setting with high union rates, short time to union and low complication rates. It can be satisfactorily employed for ankles with significant deformity, although this resulted in a longer time to union. The end results remain uniformly good to excellent.  相似文献   
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Background: Surveillance following surgery for colorectal cancer aims to detect treatable disease relapse or metachronous neoplasia. Metachronous cancers have been reported within a short duration of follow‐up, and may be due to missed lesions, seeding into polypectomy wounds or accelerated tumorigenesis related to genetic instability. The purpose of this study was to establish the timing and method of detection of metachronous cancers in a large population of patients in a surveillance database. Methods: This retrospective clinical study used patients with an elevated risk of colorectal neoplasia included in a colonoscopy‐based surveillance programme to identify those with two or more colorectal cancers, as well as the timing and method of detection of the tumours. Colonoscopy reports and histopathology results were reviewed to determine quality of bowel preparation, tumour location, and polypectomy data. Results: Fourteen (2.5%) of 569 patients with colorectal cancer developed metachronous malignant tumours, nearly half of which were identified within 3 years of follow‐up by surveillance colonoscopy or an interval faecal immunochemical test for globin. None of these had a previous polypectomy at the site of the second tumour, bowel preparation at the original colonoscopy was good in most cases, and no metachronous tumour occurred at a colonic flexure. Conclusion: Metachronous cancers can occur early during follow‐up after curative intent resection, and early colonoscopic surveillance may be warranted.  相似文献   
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The aim of a surgical residency program is to produce competent professionals displaying the cognitive, technical, and personal skills required to meet the needs of society. Current changes to the delivery of healthcare necessitate the development of new models of training. These can be supported with the development of new technologies to train and assess surgical practitioners. This article describes recent developments within Imperial College London with regard to eye tracking, noninvasive brain imaging, and an innovative mentoring scheme for the new surgical curriculum. The concept of eye tracking is described, together with surgical application for this technique in terms of dexterity analysis during minimally invasive procedures. We have also begun to understand spatial localization within the brain cortex during surgical knot-tying tasks. The aim is to develop a map of the cortex with regard to surgical novices and experienced surgeons and then to develop the hypothesis that a translational process of cortical plasticity occurs during training. Finally, the article is intended to describe a training scheme that goes beyond dexterity, and moves toward the development of a successful surgeon through surgical mentoring. It is hoped that some of these tools will enhance the training of future surgeons in order to continue to provide a high-quality service to our patients.  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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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   
60.
The hemolytic plaque assay technique can be used to detect specific hormone release from single pituitary cells. Using antisera raised against murine GH or rat PRL, we have enumerated the active lactotropes and somatotropes from male and female rat pituitary glands. These studies reveal sex-related differences in the number of cells exporting GH and PRL among anterior pituitary cells in culture. In the presence of human GH-releasing factor (hGRF), the mean percentage of GH cells was 53% in males and 30% in females (P less than 0.005). The mean percentage of PRL cells was 15% in males and 39% in females (P less than 0.008). These values were not significantly altered when hGRF was omitted. The sum of GH and PRL cells identified in separate plaque assays significantly exceeds the number obtained when GH and PRL cells were determined concurrently with a simultaneous plaque assay for both hormones. This difference is dependent on the presence of hGRF, since there was no difference when hGRF was omitted. These data identify the mammosomatotrope in numbers lower than previous reports. By this approach, the mammosomatotrope subpopulation numbers about 5% of all cells in culture. In summary, we demonstrate a sex-related difference in the number of cells exporting GH or PRL among pituitary cells in culture. This difference corresponds with and may underly sex-related differences in the responsiveness of GH and PRL secretion from the pituitary gland. Furthermore, a minor subpopulation of normal pituitary cells appears capable of simultaneous secretion of both GH and PRL.  相似文献   
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