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Background and Aim: We investigated the role of the prophylactic administration of the antioxidant 2‐mercaptoethane sulfonate (mesna) on the hepatocyte‐regenerating capacity following partial hepatectomy (PH) with concurrent Pringle maneuver. Methods: Wistar rats were subjected to PH (70% hepatectomy), 30 min Pringle maneuver, PH plus Pringle with or without mesna pretreatment (400 mg/kg, per os, 3 h before Pringle), or sham operation. At 24 h, 48 h, 72 h, and 1 week after operation, relative liver weight, hepatocyte mitotic activity (mitotic index), the histopathological score and serum aspartate aminotransferase, and alanine aminotransferase concentrations were assessed. At 1 h after operation, oxidative stress markers (glutathione to glutathione disulfide ratio, malondialdehyde concentration, and superoxide dismutase activity) and nuclear factor‐κB (NF‐κB) activity were assessed. Results: Hepatectomy stimulated the regenerating process and induced mild oxidative stress and the activation of NF‐κB in hepatocytes, while causing tissue injury in the remnant liver. When PH was performed under Pringle maneuver, hepatocyte mitotic activity was substantially suppressed, although Pringle alone initiated a delayed regenerating response. Furthermore, Pringle maneuver deteriorated oxidative stress markers, markedly increased NF‐κB activity, and aggravated tissue injury, as compared to hepatectomy alone. Mesna pretreatment prevented the Pringle‐induced antimitotic effect and the induction of oxidative stress, inhibited the activation of NF‐κB, while attenuating liver injury after PH under Pringle. Conclusion: The excessive activation of NF‐κB is related to the suppression of hepatocyte‐regenerating activity following PH with concurrent liver ischemia. Mesna pretreatment protects the liver against the Pringle‐induced antimitotic effect after PH via the prevention of oxidative stress and the inhibition of NF‐κB activation.  相似文献   
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AIM:To analyze retrospectively the records of 294 conse-cutive patients operated upon for gallbladder stones, to determine the predictive factors of synchronous common bile duct (CBD) stones and validate prospectively the generated model. METHODS: The prognostic estimation of a biochemical test and ultrasonography alone to differentiate between the absence and presence of choledocholithiasis was assessed using receiver operating characteristics curve analysis. Multivariate analysis was employed using discriminant analysis for establishment of a best model.Prospective validation of the model was made. RESULTS: Discriminant forward stepwise analysis disclosed that high values (≥2×normal) of SGOT,ALP, conjugated bilirubin and CBD diameter on ultrasound ≥10 mm were all prognostic factors of CBD lithiasis in univariate and multivariate analysis, P<0.01. History was not included in the model.Prospective validation of the model was performed by multivariate analysis using Visual General Stepwise Regression. Positive predictive value, when considering all these predictors,was 93.3%,while the negative predictive value was 88.8%.Sensitivity of the model was 96.5% and specificity 80%. CONCLUSION: The above model can be objectively applied to predict the presence of CBD stones.  相似文献   
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Long-term outcome of pneumatic dilation in the treatment of achalasia   总被引:8,自引:0,他引:8  
OBJECTIVE: Achalasia is a well-defined esophageal motor disorder for which pneumatic dilation is an established therapeutic method. Even though it has been used for several years, there are limited data on the long-term outcomes of patients treated with this procedure. Hence, we aimed to evaluate the long-term efficacy of pneumatic dilation to control the symptoms of achalasia. METHODS: The medical records of all patients treated in our unit for achalasia with pneumatic dilation were reviewed. We identified the long-term result of the initial procedure, the date of the first dilation, and the time interval between dilation and retreatment. RESULTS: Of 260 patients who were treated with pneumatic dilation, 153 (67 men, 86 women) were followed up for more than 5 yr. The mean follow-up period was 11.09 +/- 3.91 yr, and the success rate of the dilation was 75.8%. Among these patients, 35 (19 men, 16 women) had follow-up periods of more than 15 yr. The mean follow-up time of those patients was 16.56 +/- 1.09 yr, and the success rate was 51.4%. Kaplan-Meier survival analysis showed that, overall, 50% of patients develop recurring symptoms after 10.92 yr. CONCLUSIONS: Although 51.4% of patients continued to be in clinical remission more than 15 yr after the initial pneumatic dilation, the long-term success rate of pneumatic dilation seems to drop progressively with time.  相似文献   
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Large gastric phytobezoars may occur in patients with gastric dysmotility disorders. Treatment options include dissolution with enzymes, endoscopic fragmentation with removal or aspiration, and surgery. We report our experience with nasogastric cola lavage therapy. Over an 8-year period, five consecutive patients were referred to our unit for endoscopic treatment of large gastric phytobezoars. They included one patient with lobectomy for lung cancer and four patients with diabetic gastroparesis. An initial attempt of endoscopic fragmentation and removal was unsuccessful. Patients were treated with 3 l of Coca-Cola nasogastric lavage over 12 h. Nasogastric lavage was very well tolerated by the patients. Complete phytobezoar dissolution was achieved in one session in all cases. There were no procedure-related complications. The dissolution of large gastric phytobezoars with cola nasogastric lavage is a safe, rapid and effective method. Patients may be treated in the medical ward, avoiding therapeutic endoscopy or surgery.  相似文献   
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