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41.
PURPOSE: We report the evolution of endoscopic treatment of ectopic ureteroceles from the unroofing technique to a novel approach using concomitant ureterocele double puncture and intraureterocele fulguration. We also compare the results of different endoscopic modalities at a single center. MATERIALS AND METHODS: We reviewed the records of 46 children with ectopic ureteroceles who were treated endoscopically between 1995 and 2005. The patients were divided into 2 main groups. Group 1 included 17 patients who underwent common endoscopic treatments, including ureterocele incision (4 patients), single ureterocele puncture (4), and single puncture with insertion of a Double-J stent (9). Group 2 included 29 children who underwent ureterocele double puncture and fulguration of the anterior and posterior walls of the collapsed ureterocele after insertion of a Double-J stent into both punctured sites. We also managed concomitant vesicoureteral reflux by endoscopic injection of tricalcium phosphate ceramic into the subureteral region. RESULTS: Total success rates in group 1 were 0%, 25% and 33% in patients who underwent ureterocele incision, single ureterocele puncture and single puncture with insertion of a stent, respectively. Total success rate in group 2 was 90% (p<0.05). New onset vesicoureteral reflux developed in 8 patients (47%) in group 1, of which 6 were in ureterocele moieties, and in 8 patients (28%) in group 2, with none in a ureterocele moiety (p<0.01). A total of 13 patients (76%) in group 1 required open surgical intervention, compared to 3 (10%) in group 2 (p<0.05). CONCLUSIONS: This new endoscopic approach is highly effective in the treatment of children with ectopic ureteroceles.  相似文献   
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OBJECTIVES: To audit the management of vascular trauma in Kuwait, 1992-2000. DESIGN: Retrospective open study. SETTING: Vascular surgery unit, teaching hospital, Kuwait. SUBJECTS: 155 patients with vascular injuries, most of which (n = 118) involved the extremities. 21 had neck injuries, 10 abdominal, and 6 chest. INTERVENTION: Revascularisation usually using the long saphenous vein in addition to direct repair or end-to-end anastomosis. MAIN OUTCOME: Morbidity (amputation) and mortality. RESULTS: Four lower limb grafts failed, two of which (2/69, 3%) required amputation. Overall, four patients died (3%), one of pulmonary embolism and 3 of severe injuries to major abdominal vessels. 3/10 patients with abdominal vascular trauma died. Mean (SD) follow up period was 4.4 (2) years. CONCLUSIONS: Civilian violence has increased in Kuwait. Vascular trauma to abdominal vessels is associated with high mortality. Autogenous saphenous vein forms an excellent conduit for revascularisation.  相似文献   
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Background  

Balanced forces around the hip joint are critical for normal development of the hip joint, so it should be considered in every hip reconstructive procedure.  相似文献   
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This research provides a new framework based on a hybrid of block‐pulse functions and Legendre polynomials for the numerical examination of a special class of scalar nonlinear fractional optimal control problems involving delay. The concepts of the fractional derivative and the fractional integral are employed in the Caputo sense and the Riemann‐Liouville sense, respectively. In accordance with the notion of the Riemann‐Liouville integral, we derive a new integral operator related to the proposed basis called the operational matrix of fractional integration. By employing two significant operators, namely, the delay operator and the integral operator connected to the hybrid basis, the system dynamics of the primal optimal control problem converts to another system involving algebraic equations. Consequently, the optimal control problem under study is reduced to a static optimization one that is solved by existing well‐established optimization procedures. Some new theoretical results regarding the new basis are obtained. Various kinds of fractional optimal control problems containing delay are examined to measure the accuracy of the new method. The simulation results justify the merits and superiority of the devised procedure over the existing optimization methods in the literature.  相似文献   
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Implantable devices in direct contact with flowing blood are associated with the risk of thromboembolic events. This study addresses the need to improve our understanding of the thrombosis mechanism and to identify areas on artificial surfaces susceptible to thrombus deposition. Thrombus deposits on artificial blood step transitions are quantified experimentally and compared with shear stress and shear rate distributions using computational fluid dynamics (CFD) models. Larger steps, and negative (expanding) steps result in larger thrombus deposits. Fitting CFD results to experimental deposit locations reveals a specific shear stress threshold of 0.41 Pa or a shear rate threshold of 54 s?1 using a shear thinning blood viscosity model. Thrombosis will occur below this threshold, which is specific to solvent‐polished polycarbonate surfaces under in vitro coagulation conditions with activated clotting time levels of 200–220 s. The experimental and computational models are valuable tools for thrombosis prediction and assessment that may be used before proceeding to clinical trials and to better understand existing clinical problems with thrombosis.  相似文献   
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Burki T  Hamid R  Duffy P  Ransley P  Wilcox D  Mushtaq I 《The Journal of urology》2006,176(3):1138-41; discussion 1141-2
PURPOSE: The aim of this study was to determine whether redo bladder neck reconstruction is effective in achieving continence after a failed bladder neck reconstruction procedure. MATERIALS AND METHODS: We retrospectively reviewed the hospital records of patients with bladder exstrophy who had undergone redo bladder neck reconstruction. There were 30 patients in the study, including 20 boys and 10 girls. Mean patient age at redo bladder neck reconstruction was 9.3 years (range 3.2 to 15.5). The patients were divided into 3 groups on the basis of the preoperative pattern of incontinence--incomplete wetters, complete wetters and those on continuous suprapubic drainage. Of the patients 15 already had undergone bladder augmentation, 12 had undergone a Mitrofanoff procedure and 12 had been treated with bulking agents injected in the bladder neck in an attempt to achieve continence. Four patients had undergone more than 1 bladder neck procedure. The patients were investigated with a combination of noninvasive urodynamics, cystoscopy, cystogram and ultrasound. All patients underwent Mitchell's modification of Young-Dees-Leadbetter bladder neck reconstruction. Additional procedures performed included augmentation cystoplasty and Mitrofanoff formation. RESULTS: Mean followup was 6.9 years (range 1.2 to 15.5). Postoperatively 28 patients were using clean intermittent catheterization to empty the bladder (5 per urethra, 23 via Mitrofanoff). Two patients remained on continuous suprapubic catheter drainage. A total of 18 patients (60%) were dry postoperatively (80% of girls and 50% of boys). Among dry patients only 3 were performing clean intermittent catheterization per urethra and 15 via a Mitrofanoff channel. No patient was able to void per urethra without the need for clean intermittent catheterization. The 2 patients on continuous suprapubic catheter drainage continued to remain so. At night only 50% of the patients were dry (5 on free drainage, 4 on clean intermittent catheterization, 6 not on any drainage). Those patients who did not respond satisfactorily to redo bladder neck reconstruction underwent subsequent additional procedures, which included injection of bulking agents (3 patients), insertion of an artificial urinary sphincter (1), Mitrofanoff formation (2) and bladder augmentation plus Mitrofanoff channel (1). Postoperative complications included difficulty with clean intermittent catheterization (8 patients), perivesical leak (1), recurrent epididymo-orchitis (1), upper urinary tract dilatation (2) and incisional hernia (1). Bladder neck closure was being considered in 5 patients. CONCLUSIONS: In our experience redo bladder neck reconstruction cannot achieve continence with volitional voiding per urethra. Although redo bladder neck reconstruction can render a significant number of patients dry, it is only effective if performed in conjunction with augmentation. Failure of the initial bladder neck reconstruction may be a reflection of a bladder that is of inadequate capacity and/or compliance. Therefore, bladder augmentation should be considered in all patients requiring redo bladder neck reconstruction. Bladder neck closure may be a better alternative to redo bladder neck reconstruction.  相似文献   
50.
Background:Nephron sparing surgery is a well-established surgical procedure for patients with small/bilateral renal masses. During the procedure, hilar control can be achieved by using bulldog clamps individually on the renal vessels, the renal artery alone without clamping the vein, or a laparoscopic Satinsky clamp for en bloc hilar clamping. In our series, we described the outcome of laparoscopic nephron sparing surgery using a Satinsky clamp for hilar control.Materials and methods:All eligible cases with confirmed diagnosis of a renal mass were advised of nephron sparing surgery. The short-term outcomes were evaluated by warm ischemia time (using a Satinsky clamp especially when CT renal angiography was not available), average blood loss, and length of postoperative hospital stay. The oncological outcome was evaluated by noting the surgical margins of histopathological specimen, local recurrence, and distant metastasis.Results:Of 30 cases 20 were male. The mean age was 54.25 years. On preoperative evaluation, 24 cases were T1a stage and the rest were 6 T1b stage. Four tumors were located in the upper pole, 4 in the posterior midpole, and 22 in the lower pole. Twenty-six patients had a low complexity score on RENAL scoring (ie, 4–6) and 4 patients a medium complexity score (ie, 7–9). Three patients were converted to open partial nephrectomy because of technical difficulty in intracorporeal suturing and difficulty in achieving hemostasis. Among these 3 patients, 2 patients had posterior base tumors and 1 had a lower polar tumor. Average blood loss was 350 ml, warm ischemia time was 28.46 minutes, and postoperative stay was 4.55 days. Of 30 specimens for histopathology, 23 (76%) were clear cell renal cell carcinoma (RCC), 4 (13%) were papillary RCC, 1 (3.3%) was chromophobe RCC, whereas 2 (6.6%) were benign (oncocytoma). Margins were free of tumors in all the patients with no recurrence in 2 years of follow-up.Conclusion:Laparoscopic partial nephrectomy by using a Satinsky clamp as a tool for en bloc hilar clamping in the proper axis at the hilum takes care of multiple vessels irrespective of size and number, particularly when renal angiography is not available. This technique of en bloc hilar clamping is quite useful especially in developing countries where robotic facilities are not available. The Satinsky clamp decreases blood loss and intraoperative time.  相似文献   
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