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81.
We examined the effect of dietary supplementation with L-arginine on breath condensate VEGF, exhaled nitric oxide (NO), plasma erythropoietin, symptoms of acute mountain sickness, and respiratory related sensations at 4,342 m through the course of 24 h in seven healthy male subjects. Serum L-arginine levels increased in treated subjects at time 0, 8, and 24 h compared with placebo, indicating the effectiveness of our treatment. L-arginine had no significant effect on overall Lake Louise scores compared with placebo. However, there was a significant increase in headache within the L-arginine treatment group at 12 h compared with time 0, a change not seen in the placebo condition between these two time points. There was a trend (p = 0.087) toward greater exhaled NO and significant increases in breath condensate VEGF with L-arginine treatment, but no L-arginine effect on serum EPO. These results suggest that L-arginine supplementation increases HIF-1 stabilization in the lung, possibly through a NO-dependent pathway. In total, our observations indicate that L-arginine supplementation is not beneficial in the prophylactic treatment of AMS.  相似文献   
82.
We describe a case of difficult intubation in a patient suffering from ankylosing spondylitis undergoing total hip replacement surgery. The anesthetic management of 42 year old patient with difficult airway is discussed. Failure of epidural anesthesia procedure necessitated general anesthesia. The problems of performing awake fibreoptic intubation and other alternative techniques to secure the airway are described. Cervical spine involvement in ankylosing spondylitis is of great concern for the anesthetist. Longstanding progressive course of this disease leads to fibrosis, ossification and ankylosis of entire spine and sacroiliac joints. Cervical spine mobility is decreased and in severe cases total fixity occurs in a flexed position. Patient may also have atlanto-occipital and temporo-mandibular joint involvement as well. Cricoarytenoid cartilages involvement may result in upper airway compromise. Furthermore cervical spine vertebrae are prone to fractures, especially on hyperextension and may lead to spinal cord transection and quadriplegia. In this case report we describe the airway management of such patient with fixed rigidity of cervical spine and thoracolumbar kyphosis.  相似文献   
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Patients with chronic liver disease (CLD) often have neurological sequelae, of which hepatic encephalopathy is the most frequent and reversible. Rare irreversible complications of CLD are acquired (non Wilsonian) hepatocerebral degeneration (AHCD) and hepatic myelopathy (HM). To our knowledge, AHCD has rarely been reported in patients with hepatitis C virus (HCV) infection. We report a patient with HCV infection who developed AHCD and resulted in serious complications.  相似文献   
85.
Recognition of postoperatively retained foreign body, referred euphemistically as gossypiboma, is essential but is very often considerably delayed. Legal implications as well as confusing configuration patterns cause considerable dilemma in the accurate diagnosis. A good understanding of the radiological appearances of this foreign body helps in appropriate early management of such patients. We present computed tomographic features of gossypiboma in patient who presented with symptoms of fever and pain in the immediate postoperative period.  相似文献   
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BACKGROUND: Objective analysis methods of surgical performance are now available so comparison between surgeons is available. One such method is by direct observation using the Objective Structured Assessment of Technical Skills (OSATS), but this is a time-consuming process; therefore, a simple screening tool for the ability to detect errors (previously validated) was analyzed and considered as a predictor of qualitative performance. METHODS: Thirty-eight volunteer surgeons were recruited to the skills laboratory to undertake 3 exercises. Two were bench-top surgical tasks that were scored using the global rating of the OSATS technique. The third task was the ability to detect simple errors in 22 synthetic models of common surgical procedures, some of which contained purposefully made errors. P<.05 was deemed to be statistically significant. RESULTS: The scores (interquartile ranges in parentheses) for the 3 sections were excision of sebaceous cyst=21 (19,24), closure of small bowel enterotomy=23 (21,27), and identification of errors=31 (27,34). Three scorers blinded to the operative models exhibited an interobserver reliability of .9 and .91 for the video tasks, respectively. Spearman's rank correlations between the error examination and performance on the 2 tasks were both statistically significant at .69 (cystectomy) and .54 (enterotomy). CONCLUSIONS: The ability to detect simple surgical errors is a predictor of technical skill and performance of bench tasks. What must be answered is whether the use of such models and principles can shorten the qualitative surgical learning curve.  相似文献   
88.
Selection of an appropriate approach to treat full thickness rectal prolapse remains problematic and controversial. We propose that rectal prolapse may be classified as ‘low type‘ (true rectal prolapse) or ‘high type’ (intussusception of the sigmoid with a fixed lower rectum). This assessment can be made via a simple clinical test of digital rectal assessment of lower rectal fixity (‘the hook test’) based on anatomic changes in rectal prolapse to guide the selection process. In cases with the low-type prolapse, a perineal approach is appropriate (either Delorme’s procedure, or rectosigmoidectomy with or without pelvic floor repair). For the high type, an abdominal rectopexy with or without high anterior resection is needed. Retrospective analysis of our cases treated over the last 6 years showed a recurrence rate of 6% in perineal procedures and 0% in abdominal rectopexy combined with resection to date. We believe that employing our simple test and classification can contribute to better patient selection for either approach, minimize anaesthetic and surgical risks and also result in lower recurrence rates.  相似文献   
89.
This article provides information and a commentary on trials presented at the European Society of Cardiology meeting held in September 2005, relevant to the pathophysiology, prevention and treatment of heart failure. All reports should be considered as preliminary data, as analyses may change in the final publication. In the CARE-HF extension study, the benefits of cardiac resynchronisation therapy (CRT) observed in the original study were maintained over an increased follow-up period. A study of oral enoximone (25-50 mg t.i.d.) in advanced heart failure (ESSENTIAL) showed limited benefit compared to placebo. The CIBIS-III study showed that heart failure therapy could be safely initiated with bisoprolol followed by the addition of enalapril. A subcutaneous ICD system (S-ICD) showed potential as an alternative to a transvenous ICD. In the ISSUE-2 study, an implantable loop recorder was used to guide therapy in patients with recurrent syncope. The selective endothelin antagonist sitaxsentan improved 6-MWT and functional class in patients with pulmonary arterial hypertension in the STRIDE-2 study. In SOFA, fish oil had no beneficial effect on the incidence of life-threatening arrhythmias in patients with an ICD. In IMAGINE, quinapril showed no benefit when administered to patients following CABG. Perindopril reduced cardiac remodelling in post-MI patients with normal LV function in PREAMI. SIRIUS-II showed encouraging results for the use of intravenous ularitide in symptomatic decompensated chronic heart failure. The ACTIVE W study of warfarin versus aspirin plus clopidogrel in atrial fibrillation has been stopped due to superiority of warfarin.  相似文献   
90.
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