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41.
BACKGROUND/AIMS: This experimental study was designed to evaluate histological changes of the kidney and renal tissue levels of malondialdehyde (MDA), reduced glutathione (GSH), and nitric oxide (NO) and the effect of resveratrol on these metabolites after bile duct ligation in rats. METHODS: Secondary biliary cirrhosis was induced by bile duct ligation for 28 days. Swiss albino rats were divided into three groups. Group 1: Sham (n=7), Group 2: Bile duct ligation (n=7), Group 3: Bile duct ligation plus resveratrol (n=7). Bile duct ligation (BDL) plus resveratrol group received 10 mgr/kg dose of resveratrol intraperitoneally daily throughout 28 days. Kidney tissues were harvested to determine the tissue levels of MDA, GSH, and NO activity. Liver and kidney tissues were removed for light microscopic evaluation. RESULTS: Cholestasis was determined by biochemical and pathologic examination. In the resveratrol-treated rats, levels of MDA were significantly lower than those of the BDL group (p < 0.04). The levels of GSH in the resveratrol-treated rats were significantly higher than those in the BDL group (p < 0.01). The levels of NO in the resveratrol group were significantly lower than those in the BDL group (p < 0.01). CONCLUSION: The present study demonstrates that intraperitoneal administration of resveratrol in bile duct ligated rats maintains antioxidant defenses and reduces kidney oxidative damage. This effect of resveratrol may be useful in the preservation of renal oxidative stress in cholestasis.  相似文献   
42.
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   
43.

Background:

We herein report a laparoscopically performed re-do operation on a patient who had previously undergone a laparoscopic parastomal hernia repair.

Case Report:

We describe the case of a 71-year-old patient who presented within 3 months of her primary laparoscopic parastomal hernia repair with recurrence. On relaparoscopy, dense adhesions to the mesh were found, and the mesh had migrated into the hernia sac. This had allowed loops of small bowel to herniate into the sac. The initial part of the procedure involved the lysis of adhesions. A piece of Gore-Tex DualMesh with a central keyhole and a radial slit was cut so that it could provide at least 3 cm to 5 cm of overlap of the fascial defect. The tails of the mesh were wrapped around the bowel, and the mesh was secured to the margins of the hernia with circumferential metal tacking and 4 transfascial sutures. The patient remains in satisfactory condition and no recurrence or any surgery-related problem has been observed during 8 months of follow-up.

Conclusion:

Revisional laparoscopic repair of parastomal hernias seems feasible and has been shown to be safe and effective in this case. The success of this approach depends on longer follow-up reports and standardization of the technical elements.  相似文献   
44.
BACKGROUND: The type of stent used for the management of patients with malignant dysphagia is chosen according to subjective physician's preference. There is no recent study available to provide updated evidence on early outcomes related to the use of different types of stents. METHODS: A literature search was performed using Embase, MEDLINE, Cochrane Library, and Google Scholar databases for comparative studies assessing different types of stents. The primary end point was stent-related mortality; secondary end points included: stent-related morbidity, successful palliation of dysphagia, and 30-day mortality. A random-effects model was used and heterogeneity was assessed. RESULTS: Twelve studies that included 911 patients compared metallic (46.54%) and plastic stents (53.45%), and eight studies that included 564 patients compared covered (43.26%) and uncovered metal stents (56.73%). Meta-analysis of randomized, controlled trials showed that metallic stents were associated with significantly reduced stent-related mortality (1.7% vs. 11.1% for the plastic group, odds ratio (OR), 0.2; 95% confidence interval (CI), 0.06-0.74; P = 0.02), morbidity in the form of reduced esophageal perforation (1.4% vs. 9.4% for plastic stent, OR, 0.27; 95% CI, 0.08-0.89; P = 0.03), and stent migration, yet increased rate of tumor in-growth (13% vs. 1.6% for plastic stents, OR, 4.84; 95% CI, 0.99-23.76; P = 0.05). Covered metallic stents had significantly less tumor in-growth than the uncovered and an increased migration rate. There was no significant difference between metallic and plastic stents in terms of any other stent-related morbidity and 30-day mortality. CONCLUSION: Self-expanding metallic stents are superior to plastic stents in terms of stent insertion-related mortality, morbidity, and quality of palliation. The uncovered variety is disadvantaged by high rate of tumor in-growth; adequately designed randomized, controlled trials need to examine outcomes and cost-effectiveness of covered versus uncovered metallic stents.  相似文献   
45.
This is a comparative study between manual volumetry (MV) and voxel based morphometry (VBM) as methods of evaluating the volume of brain structures in magnetic resonance images. The volumes of the hippocampus and the amygdala of 16 panic disorder patients and 16 healthy controls measured through MV were correlated with the volumes of gray matter estimated by optimized modulated VBM. The chosen structures are composed almost exclusively of gray matter. Using a 4 mm Gaussian filter, statistically significant clusters were found bilaterally in the hippocampus and in the right amygdala in the statistical parametric map correlating with the respective manual volume. With the conventional 12 mm filter,a significant correlation was found only for the right hippocampus. Therefore, narrow filters increase the sensitivity of the correlation procedure, especially when small brain structures are analyzed. The two techniques seem to consistently measure structural volume.  相似文献   
46.
Multi-detector computed tomography (MDCT) has become an alternative to coronary angiography in diagnosis of graft occlusion and stenosis after coronary artery bypass. A literature search was performed for studies comparing angiography to 8-slice, 16-slice, and 64-slice MDCT in the assessment of coronary grafts. In assessing occlusion, 14 studies produced pooled sensitivity of 97.6%, specificity of 98.5%, diagnostic odds ratio of 934.2, area under the curve of 0.996, and Q* of 0.977. Ninety-six percent of all grafts were visualized for occlusion assessment. Beta blockers, symptomatic status, and postoperative period did not significantly affect diagnostic performance. Stenosis assessment produced sensitivity of 88.7% and specificity of 97.4%. Eighty-eight percent of patent grafts could be assessed for stenosis. The diagnostic accuracy of MDCT approaches angiography for diagnosing graft occlusion and stenosis in patients with venous and arterial coronary bypass grafts. Our findings show that cardiac surgeons will need to interpret MDCT images of both native and grafted vessels soon in preparation for primary or re-do coronary bypass grafting procedures.  相似文献   
47.
Intramedullary epidermoid cysts of the spinal cord are rare tumors, especially those not associated with spinal dysraphism. About 50 cases have been reported in the literature. Of these, only seven cases have had magnetic resonance imaging (MRI) studies. We report two cases of spinal intramedullary epidermoid cysts with MR imaging. Both were not associated with spina bifida. In one patient, the tumor was located at D4 vertebral level; while in the other, within the conus medullaris. The clinical features, MRI characteristics and surgical treatment of intramedullary epidermoid cyst are presented with relevant review of the literature.  相似文献   
48.
OBJECTIVES: Some patients and oncologists choose to treat localized esophageal cancer with definitive chemotherapy and radiation therapy rather than surgery. A subset of these patients have local relapse without distant metastases and therefore have no other curative intent treatment option but salvage esophagectomy. METHODS: We reviewed our experience with salvage esophagectomy from 1987 to 2000 at M.D. Anderson Cancer Center (n = 13, salvage after chemotherapy and radiotherapy group) and compared the data with those of patients receiving esophagectomy in a planned fashion 4 to 6 weeks after preoperative chemotherapy and radiation therapy (n = 99, preoperative chemotherapy and radiotherapy group). RESULTS: Increases in morbidity were seen after resection in the salvage after chemotherapy and radiotherapy group relative to the preoperative chemotherapy and radiotherapy group: mechanical ventilation (9.0 days vs 3.3 days, P =.08), intensive care unit stay (11.2 days vs 5.1 days, P =.07), hospital stay (29.4 days vs 18.4 days, P =.03), and anastomotic leak rates (5/13 [39%] vs 7/99 [7%], P =.005). Operative mortality (within 30 days) also tended to be increased statistically nonsignificantly (2/13 [15%] vs 6/99 [6%], P =.2). Salvage esophagectomy resulted in long-term survival (25% 5-year survival) in a subset of patients. Improved survival after salvage esophagectomy was associated with early pathologic stage (T1 N0, T2 N0), prolonged time to relapse, and R0 surgical resection. CONCLUSION: Patients who undergo salvage esophagectomy for relapse of tumor after definitive chemoradiation therapy have increased morbidity, mortality, and hospital use relative to patients undergoing planned esophagectomy after preoperative chemoradiation. Nevertheless, long-term survival can be achieved in this group, and such treatment should be considered for carefully selected patients at an experienced center.  相似文献   
49.
Background Obesity is the most important risk factor for obstructive sleep apnea. It is estimated that 70% of sleep apnea patients are obese. In the morbidly obese, the prevalence may reach 80% in men and 50% in women. The aim of this study was to determine the prevalence and severity of sleep apnea in a group of morbidly obese patients, leading to bariatric surgery. Methods In a cross-sectional study developed in Bahia, northeastern Brazil. 108 patients (78 women and 30 men) from the Obesity Treatment and Surgery Center - “Núcleo de Tratamento e Cirurgia da Obesidade” underwent standard polysomnography. Patients with an apnea-hypopnea index (AHI) ≥ 5 events/hour were considered apneic. Results Mean ± SD for age and BMI were 37.1 ± 10.2 years and 45.2 ± 5.4 kg/m2, respectively. The calculated AHI ranged widely from 2.5 to 128.9 events/hour. Sleep apnea was detected in 93.6% of the sample, wherein 35.2% had mild, 30.6% moderate and 27.8% severe apnea. Oxyhemoglobin desaturation was directly related to the AHI and was more severe in men. Conclusion There was a high frequency of sleep apnea in this group of morbidly obese patients, for whom it was very important to request polysomnography, thus enabling therapeutic management and prognostication.  相似文献   
50.
Comparison of laparoscopic versus hand-assisted live donor nephrectomy   总被引:2,自引:0,他引:2  
BACKGROUND: The aim of the present study was to compare hand-assisted laparoscopic live donor nephrectomy with the classic laparoscopic method, using meta-analytical techniques. METHODS: A literature search was performed for studies comparing hand-assisted laparoscopic nephrectomy with classic laparoscopic nephrectomy for live kidney donation between 1999 and 2005. The following end points were evaluated: operative time, warm ischemia time, intraoperative adverse events, donor and recipient postoperative complications, and length of hospital stay. RESULTS: Nine comparative studies matched the selection criteria, reporting on 376 patients, of whom 202 (53.7%) had hand-assisted laparoscopic nephrectomy and 174 (46.3%) had the classic laparoscopic technique. Conversion to open surgery was 2.97% in the hand-assisted group and 4.60% in the laparoscopic group (P=0.35). Total operative and warm ischemia times were significantly shorter for hand-assisted laparoscopy by 30.03 minutes (P=0.02) and 1.14 minutes (P<0.001), respectively. The intraoperative blood loss was less for the hand-assisted laparoscopy group by 34.16 mL (P=0.008), although intraoperative (3.46% vs. 7.47%; P=0.24) and postoperative (5.94% vs. 10.34%; P=0.30) donor complications and recipient complications (including delayed graft function and primary nonfunction, 8.41% vs. 7.42%; P=0.32) were similar between the hand-assisted and laparoscopic groups. CONCLUSION: Hand-assisted laparoscopic nephrectomy appeared to have the same donor and recipient complication rate with standard laparoscopy but offered substantial advantages in terms of shortened operative and warm ischemia time as well as decreased intraoperative bleeding.  相似文献   
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