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Pre-excitation disorders have an estimated prevalence of 0.15 per cent. Advances in electrophysiological mapping and the increasing sophistication of surgical techniques have resulted in an increasing role for definitive surgical treatment. A retrospective chart review of 181 patients undergoing 197 procedures for surgical ablation of accessory atrioventricular pathways between June 1981 to June 1986 was performed. Mean age of the patients was 30 years (range 6-66) with a preponderance of males (59 per cent). Associated cardiac disease was found in 18 (9.9 per cent) patients. Induction of anaesthesia employed either a barbiturate-relaxant (83 per cent) or a narcotic-benzodiazepine-relaxant (17 per cent) and was uneventful in all cases. In 14 per cent of cases a pure narcotic relaxant technique was employed for maintenance of anaesthesia, whereas a balanced technique with isoflurane (29 per cent), enflurane (34 per cent), or halothane (22 per cent) was utilized for the remainder. Muscle relaxation was provided by d-tubocurarine in 35 (18 per cent) procedures and pancuronium in the remaining 162 (82 per cent) procedures. There was no significant correlation between intraoperative arrhythmias and type of anaesthetic used. Although recognizing the potential for malignant arrhythmias, our experience (within the confines of a retrospective analysis) suggests that the majority of these patients can be managed successfully using standard anaesthetic techniques.  相似文献   
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This study compares the histology of the plantar-digital nerve supplying the third web space in asymptomatic patients with those who have clinically diagnosed Morton's metatarsalgia. Despite several studies concentrating on the histological changes in the interdigital nerve, the relevance of these changes is a matter of contention while the exact pathological process responsible for the symptoms has not been determined. The histological findings in control patients were identical to Morton's patients with the exception of demyelination, which was more common in the Morton's group. This suggests that the characteristic nodule and fibrotic changes seen in the interdigital nerves of patients with Morton's neuroma cannot account for the symptoms and that the changes seen in the neurovascular bundle are degenerative in origin and are found in asymptomatic patients.  相似文献   
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Stomach rupture can occur as a consequence of the expansion of compressed air during rapid ascent after diving. We present the case of a middle-aged woman who suffered a gastric tear from surfacing too quickly after diving, and discuss the diagnosis and management of such patients by reviewing previously reported similar events. Gastric barotrauma should be suspected in divers who complain of abdominal pain, even in the absence of frank signs of peritoneal irritation. Although pneumoperitoneum is always present in these patients, it can also occur as a consequence of pulmonary barotrauma, making gastroscopy or radiological contrast studies, or both, essential for a definitive diagnosis. Surgical repair represents the treatment of choice for an active full-thickness tear and, if associated with arterial gas embolism or decompression sickness, should ideally be performed in a center where a category I (intensive care-capable) hyperbaric unit is available. Received: March 18, 2002 / Accepted: September 3, 2002 Reprint requests to: L.V. Titu  相似文献   
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OBJECTIVE: This study was designed to evaluate the efficacy of magnesium carbonate as a phosphate binder in hemodialysis patients. DESIGN: This study was a prospective, randomized, open-label trial comparing magnesium carbonate/calcium carbonate versus calcium acetate as a sole phosphate binder. SETTING: This study involved outpatient hemodialysis. PARTICIPANTS: We recruited 30 stable hemodialysis patients without a history of frequent diarrhea. INTERVENTION: After receiving informed consent, we randomized patients 2:1 to magnesium carbonate versus calcium acetate. The dose of each binder was titrated to achieve the Kidney Disease Outcomes Quality Initiative (K/DOQI) phosphate target of <5.5 mg/dL. MAIN OUTCOME MEASURE: The efficacy-phase serum phosphorus concentration and the percentage of patients meeting K-DOQI targets for phosphorus, along with the daily elemental calcium intake, were the primary outcome measures. RESULTS: Magnesium carbonate provided equal control of serum phosphorus (70.6% of the magnebind group and 62.5% of the calcium acetate group had their average serum phosphorus within the K-DOQI target during the efficacy phase), while significantly reducing daily elemental calcium ingestion from phosphate binders (908 +/- 24 vs. 1743 +/- 37 mg/day, P < .0001). CONCLUSION: Magnesium carbonate was generally well-tolerated in this selected patient population, and was effective in controlling serum phosphorus while reducing elemental calcium ingestion.  相似文献   
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With improvements in the safety of Whipple resection in recent decades, surgeons have continued to explore the role of more extensive lymphadenectomy in hope of improving long-term survival. A systematic literature search of level I evidence addressing the role of the extent of lymphadenectomy was undertaken. Only reports of prospective, randomized controlled trials comparing pancreaticoduodenectomy with standard lymphadenectomy to pancreaticoduodenectomy with extended lymphadenectomy where information regarding survival, morbidity, mortality, the number of resected lymph nodes in each group and detailed operative technique were included. Four prospective, randomized trials comprising some 424 patients and one meta-analysis were identified. In aggregate, these studies confirmed that the number of resected lymph nodes was significantly higher in the pancreaticoduodenectomy with extended lymphadenectomy group. Morbidity and mortality rates were comparable. Postoperative diarrhea in the early months after operation was problematic in patients undergoing extended lymphadenectomy. In none of the studies was a benefit in long-term survival demonstrated. Standard pancreaticoduodenectomy continues to be the operation of choice for adenocarcinoma of the head of the pancreas. Presented at The Society for Surgery of the Alimentary Tract Postgraduate Course “Systematic Reviews of Pancreaticobiliary Disease Customized for the Gastroenterologist and Gastrointestinal Surgeon” on May 20, 2007, Washington, D.C.  相似文献   
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