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11.
Chronic rejection accounts for most renal allograft losses after the first year posttransplantation. On March 24 and 25, 1997, a roundtable of five transplant surgeons, two nephrologists, and one pathologist assembled in Dallas, Texas, to review critical issues surrounding chronic renal allograft rejection. This article summarizes the presentations and relevant discussions of this meeting regarding the cause of chronic rejection, clinical diagnoses, risk factors, future prospects for intervention strategies, and general recommendations for the transplant community. Growing evidence indicates that chronic rejection is the aggregate sum of irreversible immunologic and nonimmunologic injuries to the renal graft over time. A history of acute rejection episodes and inadequate immunosuppression, likely attributable to inconsistent cyclosporine exposure or poor patient compliance, are among the most recognizable immunologic risk factors for chronic rejection. Donor organ quality, delayed graft function, and other donor and recipient variables leading to reduced nephron mass are nonimmunologic factors that contribute to the progressive deterioration of renal graft function. Clinical management of renal transplant recipients should incorporate both immunologic- and nonimmunologic-based intervention strategies aimed at minimizing risk factors to thwart the progression of chronic rejection and improve long-term allograft and patient survival.  相似文献   
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腹部外科常见感染性疾病的病原菌及药敏试验研究   总被引:1,自引:0,他引:1  
为了了解本地区本医院腹部外科感染性疾病病原菌的构成比和药物敏感率的变化,指导临床用药,我们采用美国BD公司生产的6B和7D两种增菌瓶采集标本和培养细菌,并用该公司生产的生化板和药敏板,对1994~1996年269例常见的普外科感染性疾病患者的手术标本进行前瞻性的细菌培养和药敏试验研究.  相似文献   
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Study ObjectiveTo investigate the efficiency of a double curve nasotracheal tube on lightwand-guided nasotracheal intubation.DesignProspective, randomized, controlled trial.SettingUniversity medical center hospital.Patients60 ASA physical status I and II patients undergoing oromaxillofacial surgery.Interventions and MeasurementsPatients undergoing surgery with nasotracheal intubation and general anesthesia were randomly enrolled in the laryngoscopy group or the lightwand group. The same type of double curve nasotracheal tube was used in both groups. In the laryngoscopy group, intubation was assisted with a Macintosh No. 3 standard curved blade and Magill forceps. In the lightwand group, intubation was aided with a flexible lightwand device (without the inner stiff stylet). Intubation time was divided into two parts: Part one, from selected naris to oropharynx; Part two, from oropharynx into trachea. Part one, Part two, and total intubation time, hemodynamic responses to nasotracheal intubation, and adverse events or complications were recorded.Main ResultsTotal intubation times in the lightwand group and the laryngoscopy group were 22.8 ± 8.0 sec vs 30.3 ± 8.2 sec (P < 0.001), respectively. The lightwand group had comparable hemodynamic responses to those of the laryngoscopy group. Adverse events and complications were all self-limited, with similar occurrence in both groups.ConclusionFor patients undergoing oromaxillofacial surgery, modified lightwand-guided nasotracheal intubation is feasible with a double curve nasotracheal tube and is an efficient alternative technique.  相似文献   
14.
Background  The association between primary sclerosing cholangitis (PSC) and ulcerative colitis (UC) often mandates their contemporaneous management. Orthotopic liver transplantation (OLTX) has emerged as the only curative therapy for PSC, and total proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the definitive treatment for refractory UC. The published experience to date describing IPAA after OLTX has been limited; we sought to examine outcomes associated with proctocolectomy-IPAA after OLTX. Materials and Methods  We reviewed our multi-institutional experience performing proctocolectomy-IPAA for UC after OLTX for PSC. Results  Twenty-two patients underwent proctocolectomy-IPAA for UC after OLTX for PSC at four academic medical centers between 1989 and 2006. No perioperative complications or allograft dysfunction were observed. During a median follow-up of 52 months, complications have included transient dehydration (n = 6), chronic pouchitis (n = 2), recurrent PSC (n = 2), small bowel obstruction (n = 2), and pouch-anal anastomotic stricture (n = 1). Median 24-h stool frequency was 5, and fecal continence was reported as satisfactory by all patients. Conclusions  This multi-institutional experience suggests that proctocolectomy-IPAA can be performed safely after OLTX. Management strategies should include optimization of small bowel length during pouch and ileostomy construction, vigorous postoperative hydration, early ileostomy closure, and careful monitoring for pouchitis.  相似文献   
15.
Results after colectomy for colonic inertia: a sixteen-year experience   总被引:6,自引:0,他引:6  
BACKGROUND: Colonic inertia (CI) is a disturbance of colonic motility characterized by severe constipation and abdominal pain. This study was conducted to assess the results of total abdominal colectomy (TAC) in the management of CI. METHODS: A retrospective chart review of 55 patients who underwent TAC for CI was conducted. RESULTS: Forty-eight patients (87%) were female with an average age of 40; severe constipation existed 2 years prior to surgery. Symptoms included severe constipation (100%) and abdominal pain (84%); diagnostic workup included sitz marker study, anal manometry, and Gastrografin enema. In all cases, sitz marker studies were abnormal and anal manometry was normal. Histologically, no patient had absence of neuroenteric plexuses. Complications included prolonged ileus (24%) and small bowel obstruction (8%). Some 49 patients (89%) had "good" or "excellent" results and 6 patients (11%) had "poor" results. Postoperative stool frequency was 5, 4, and 3 per day at 1, 2, and 12 months, respectively. CONCLUSIONS: TAC results in resolution of constipation in most patients. We conclude that TAC is effective treatment in patients with CI.  相似文献   
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The effects of four weeks of continuous illumination (LL), a subacute stress, on gastric mucosal endogenous aggressive and defensive factors were studied. Young male Sprague-Dawley rats were used with two different illumination regimens: LL and 12 hr light/12 hr dark (LD). At the end of three to four weeks of either regimen of illumination, gastric acid secretion, pepsin secretion, mucus secretion, and potential difference (PD) were studied. All gastric parameters, except mucus secretion, were significantly reduced by LL. The reduction in acid secretion (13.3%) was not significant after Bonferroni correction for the fourt tests Pepsin secretion and PD were 27.9% and 24.6% less, respectively. These differences were significant after Bonferroni correction. The LD rats showed significant circadian rhythms for acid, mucus, and pepsin secretion. The LL rats showed significant rhythmicity for these same parameters with period lengths different from 24 hr. Gross inspection of the gastric mucosa indicated that 69.8% of the LL rats had lesion scores of 1.0 or higher, while none of the LD rats had scores above 0.5.The authors acknowledge the Salt Lake Veterans Administration Medical Center, Department of Research, for support of this study.  相似文献   
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We have postulated that the accelerated snythesis of cholesteryl ester in atherosclerotic microsomes may result in part from decreased acyl-CoA hydrolase activity in arterial tissue, because acyl-CoA is a common substrate for both reactions. We have now investigated the influence of nutritional status, type of diet, and diabetes on the acyl-CoA hydrolase activity of otherwise normal aortic microsomes. Fasting rabbits for 16 hr diminished the acyl-CoA hydrolase activity approximately 30%. The activity of this aortic microsomal enzyme in rats maintained on a high-carbohydrate diet for 5 weeks was comparable to the activity observed on a high fat (olive oil) diet. The type of fat in the diet influences the acyl-CoA hydrolase activity: oils containing 77% oleic acid (high-oleic safflower oil) and containing 70% linoleic acid (conventional safflower oil) lowered the aortic microsomal acyl-CoA hydrolase activity in comparison to a more saturated fat (cocoa butter). Aortic preparations of rats made diabetic by streptozotocin exhibited higher acyl-CoA hydrolase activity than the normal. The results show that conditions associated with human atherogenesis (diabetes and saturated fat diet) increase rather than suppress the activity of this arterial enzyme in normal arterial tissues of the rat.  相似文献   
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