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991.
OBJECTIVES: This investigation was undertaken to compare a series of elderly individuals who sustained a displaced femoral neck fracture treated with either a cemented bipolar prosthesis or a cemented modular unipolar prosthesis. DESIGN: A retrospective review of prospectively collected data. SETTING: Hospital-based tertiary care orthopaedic trauma practice. PATIENTS AND PARTICIPANTS: Two hundred eighty-one community dwelling elderly patients sixty-five years of age or older who sustained a displaced femoral neck fracture (Garden Types III-IV) and underwent primary prosthetic replacement. INTERVENTION: One hundred one patients received a cemented bipolar prosthesis and 180 received a cemented modular unipolar prosthesis. MAIN OUTCOME MEASUREMENTS: The study was designed to determine whether there were any significant differences in: (a) the rate of prosthetic dislocation, postoperative medical and wound complications, or need for revision surgery, and (b) the functional outcome, including the incidence of hip pain and recovery of preinjury levels of ambulatory status and activities of daily living, at a minimum of thirty-six months of follow-up. RESULTS: The two groups of patients did not differ in preinjury characteristics (age, sex, American Society of Anesthesiologist rating of operative risk, number of comorbidities, fracture type, activities of daily living, ambulatory status). There were no significant differences in the rates of postoperative medical or wound complications or dislocation. Ninety-two patients died during the period of study. Forty patients were lost to follow-up or refused to participate. Consequently, 149 patients were followed for a minimum of thirty-six months. Functional ability was compared between both groups with regard to recovery of ambulatory status and activities of daily living, as well as the incidence of hip pain at a minimum of thirty-six months of follow-up. No significant differences were found between the unipolar and bipolar groups. CONCLUSION: Based on the results of this study, there does not appear to be any advantage to the use of a bipolar endoprosthesis in the management of displaced femoral neck fractures in the elderly. Furthermore, the extra cost of bipolar endoprostheses does not seem to warrant its use.  相似文献   
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Danger of systemic cyclosporine for corneal graft   总被引:5,自引:0,他引:5  
PURPOSE: To report a case of posttransplant lymphoproliferative disorder (PTLD) in a patient receiving oral cyclosporine (CS) for immunosuppression in a high-risk keratoplasty. METHODS: A systemic CS therapy was given to prevent graft rejection of a keratoplasty. Risk rejection was high in regard to a previous graft rejection and persistence of a corneal vascularization. One year after the keratoplasty, the patient developed a gastric Epstein-Barr virus (EBV)-induced B cell lymphoma. The outcome was favorable after chemotherapy. CONCLUSIONS: This unique case of lymphoma (PTLD) in the course of corneal graft management questions the indications and the follow-up of patients with CS therapy and raises the issue of topical CS treatment.  相似文献   
995.
The inhibition of nitric oxide (NO) synthesis by chronic administration of NG-nitro-l-arginine methyl ester (l-NAME) in rats is responsible for systemic hypertension. However, the mechanisms involved in this hypertension remain unclear. The effects of chronic l-NAME on kidney and blood NO production were studied in rats in a state of endotoxic shock due to lipopolysaccharide (LPS). A nitric oxide spin trapping technique using electron spin resonance (ESR) spectroscopy has been used to identify and measure the production of NO in the kidney. This method is based on the trapping of nitric oxide by a metal-chelator complex consisting of N-methyl-d-glucamine dithiocarbamate (MGD) and reduced iron (Fe2+) forming a water-soluble NO-FeMGD complex detected by ESR. After LPS injection (14 mg/kg, IV, 6 h before the sacrifice) to rats pretreated with l-NAME (10 mg/kg/d over 14 days), the NO-FeMGD complex was evaluated in the kidney (arbitrary units [AU]/g of kidney) and the density of polynuclear neutrophils was counted by light microscopy. Chronic inhibition of NO synthase by l-NAME, a nonspecific inhibitor, was responsible for a decrease of the NO-FeMGD complex levels in the kidney (24.9 +/- 1.6 AU versus 13.8 +/- 1.3 AU). LPS administration was responsible for a large increase in both NO-FeMGD complex and neutrophil levels in the kidney of normotensive rats (332.6 +/- 12.8 AU versus 24.9 +/- 1.6 AU for NO-FeMGD complex and 1.36 +/- 0.41 versus 0.11 +/- 0.03 for neutrophils). Conversely, LPS administration in hypertensive, l-NAME-pretreated rats was linked to a smaller increase in the NO-FeMGD complex (85.1 +/- 7.9 AU versus 332.6 +/- 12.8 AU) and a larger increase in glomerular neutrophils (2.48 +/- 0.36 versus 1.36 +/- 0.41) compared with normotensive rats. These results are in agreement with a direct implication of NO during LPS-and l-NAME-induced kidney injuries.  相似文献   
996.
BACKGROUND: In patients with chronic hepatitis C, elevations in serum iron levels, hepatic iron content and oxidative stress-related molecules have been reported. Treatment with ribavirin induces an increase in hepatic iron concentration. In situations of iron overload, non-transferrin-bound iron can appear. Therefore, we determined non-transferrin-bound iron levels in untreated chronic hepatitis C patients and in patients during interferon-ribavirin treatment. MATERIALS AND METHODS: In 10 untreated and 19 interferon-ribavirin-treated chronic hepatitis C patients, we examined non-transferrin-bound iron levels by a colorimetric method using nitrilotriacetic acid as a ligand and sodium triscarbonatecobalt (III) to block free iron binding sites on transferrin. RESULTS: Despite the presence of high serum iron saturation and ferritin levels, non-transferrin-bound iron was absent in the majority of hepatitis C virus patients (25/29, 86%). There was no difference in non-transferrin-bound iron levels between untreated and treated patients. Four patients with high non-transferrin-bound iron levels were distinguished by higher serum iron levels. In two of these patients, hepatocytic iron was present on liver biopsy. CONCLUSIONS: In the majority of chronic hepatitis C patients, non-transferrin-bound iron levels are normal. Treatment with ribavirin does not induce high non-transferrin-bound iron levels. Non-transferrin-bound iron levels are only higher than normal in hepatitis C patients with higher serum iron levels.  相似文献   
997.
BACKGROUND: Randomized controlled trials testing flumazenil in hepatic encephalopathy have shown conflicting results. AIM: To compare flumazenil and placebo in hepatic encephalopathy in patients with cirrhosis. METHODS: An overview of randomized controlled trials comparing flumazenil and placebo in hepatic encephalopathy in patients with cirrhosis was performed. For each end-point, heterogeneity and treatment efficacy were assessed by Peto and Der Simonian methods. As most trials were crossover in nature, a sensitivity analysis was performed including the two treatment periods. RESULTS: Six double-blind randomized controlled trials, including 641 patients (326 treated with flumazenil and 315 with placebo), were identified. The treatment duration ranged from 5 min to 3 days. Heterogeneity tests between control groups were not significant. The mean percentages of patients with clinical improvement (five trials) were 27% in treated groups and 3% in placebo groups. This difference was significant by both methods (Peto: odds ratio=6.15; 95% confidence interval, 4.0-9.5; P < 0.001; Der Simonian: mean rate difference, 29%; 95% confidence interval, 17-41; P < 0.001). The mean percentages of patients with electroencephalographic improvement were 19% in treated groups and 2% in placebo groups. This difference was significant only with the Peto method (odds ratio=5.8; 95% confidence interval, 3.4-9.7; P < 0.001). The sensitivity analysis showed similar results. CONCLUSIONS: This meta-analysis shows that flumazenil induces clinical and electroencephalographic improvement of hepatic encephalopathy in patients with cirrhosis.  相似文献   
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