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BACKGROUND AND AIM OF STUDY: Cardioplegic arrest remains the method of choice for myocardial protection in cardiac surgery. Caffeic acid phenethyl ester (CAPE) prevents lipid peroxidation induced by ischemia-reperfusion injury and has a potent antioxidant property. We investigated the advantages of CAPE supplemented cardioplegic solution (St. Thomas' Hospital cardioplegic solution No.: 2) on the antioxidant defense system of myocardium against ischemia-reperfusion injury. MATERIAL AND METHODS: Isolated rat hearts were mounted on a nonrecirculating type of Langendorff apparatus. The hearts were arrested for 60 min with cardioplegic solution given at 20-min intervals and then reperfused for 15 min. The hearts were divided into three groups. Cold saline (0.9%, 4 degrees C) in group 1, St. Thomas' Hospital solution in group 2 and CAPE added St. Thomas' Hospital solution in group 3 were used as the cardioplegic solution. Krebs-Henseleit buffer solution was used for reperfusion. The tissues were examined biochemically for oxidative stress. RESULTS: Significant differences among the three groups existed in tissue myeloperoxidase (MPO), catalase (CAT), Na+-K+ ATPase activity and in the concentrations of malonydealdehyde (MDA) and 3-nitrotyrosine (3-NT). Group 2 showed significant changes in MPO (P = 0.04), Na+-K+ ATPase enzyme activity (P = 0.02) and the levels of MDA (P = 0.004) and 3-NT (P = 0.01) in comparison with group 1. Group 3 efficiently reduced MDA levels (P = 0.004) and also led to significant decrease in levels of MPO (P = 0.006), 3-NT (P = 0.01) and Na+-K+ ATPase activity (P = 0.01) and increase in the level of CAT (P = 0.004) in comparison with group 1. Significant changes were also found in the levels of MDA (P = 0.03), MPO (P = 0.04) and CAT (P = 0.009) in comparison between groups 2 and 3. CONCLUSIONS: We demonstrated that the administration of CAPE into cardioplegic solutions improves the antioxidant defense system of rat heart during the ischemia-reperfusion injury.  相似文献   
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The prevalence of hepatitis C virus (HCV) infection amongst a group of intravenous drug users (IVDUs) resident in West Suffolk (East Anglia, England) was investigated and compared with the prevalence of infection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV). In addition, both the level of HCV persistence, as defined by detection of viral RNA, and the HCV genotypes present in this population were determined. It was found that HCV antibodies were present in 59% of those tested; by comparison 22% had antibodies to HBV and 1% antibodies to HIV. HCV RNA was found in 44% of those with HCV antibody. HCV genotype 1 was the most prevalent within this population although both genotypes 2 and 3 were also represented. © 1995 Wiley-Liss, Inc.  相似文献   
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The early institution of enteral nutrition is now accepted as the preferred route of feeding in critically ill patients with a functioning gastrointestinal tract. It is particularly important to establish early enteral nutrition in mechanically ventilated patients because of the metabolic demands associated with mechanical ventilation. The options for enteral access in mechanically ventilated patients are reviewed, with an emphasis on those techniques that may be performed at the bedside. The advantages, disadvantages, and complications of the different techniques will be considered.  相似文献   
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AIM: To evaluate the efficacy and safety of pegylated- interferon alpha-2a in hemodialysis patients with chronic hepatitis C. METHODS: Thirty-six hemodialysis patients with chronic hepatitis C were enrolled in a controlled and prospective study. All patients were treatment naive, positive tested for anti-HCV antibodies, and positive tested for serum HCV-RNA. Twenty-two patients received 135 μg peglyated-interferon α-2a weekly for 48 wk (group A). The remaining patients were left untreated, eleven refused therapy, and three were not candidates for kidney transplantation and were allocated to the control group (group B). At the end of the treatment biochemical and virological response was evaluated, and 24 wk after completetion of therapy sustained virological response (SVR) was assessed. Side effects were monitored.
RESULTS: Of 22 hemodialysis patients, 12 were male and 10 female, with a mean age of 35.2 ± 12.1 years. Virological end-of-treatment response was observed in 14 patients (82.4%) in group A and in one patient (7.1%) in group B (P = 0.001). Sustained virological response was observed in 11 patients (64.7%) in group A and in one patient in group B (7.1%). Biochemical response parameters normalized in 10/14 patients (71.4%) at the end of the treatment. ALT levels in group B were initially high in six patients and normalized in one of them (25%) at the end of the 48 wk. In five patients (22.7%) therapy had to be stopped at mo 4 due to complications of weakness, anemia, and bleeding.
CONCLUSION: SVR could be achieved in 64.7% of patients on hemodialysis with chronic hepatitis C by a treatment with peglyated-interferon α-2a. Group A had a significantly better efficacy compared to the control group B, but the side effects need to be concerned.  相似文献   
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Use of pleural fluid C-reactive protein in diagnosis of pleural effusions   总被引:8,自引:0,他引:8  
The aims of the study were to assess whether C-reactive protein (CRP) is a sensitive marker for discriminating between transudative and exudative and pleural effusions to evaluate whether it can be used to distinguish inflammatory pleural effusions from other types of effusion. Pleural fluid and serum CRP levels were obtained in 97 patients with pleural effusion, using an immunoturbidimetric method (Olympus AU-600 autoanalyser). We compared CRP levels between transudates and exudates, inflammatory effusions and other types of effusion. According to the criteria used, 16 patients were included in the transudate group and 81 patients in the exudate group. Pleural fluid CRP levels were significantly lower in the transudate group (P<0.04; 14.9 +/- 4.9 mg l(-1) and 35.5 +/- 4.9 mg l(-1) respectively). Also, the ratio of pleural fluid to serum was significantly lower in the transudate group (P<0.009; 0.8 +/- 0.5 mg l(-1) and 2.8 +/- 0.7 mg l(-1), respectively). In the exudate group, 35 patients had neoplastic effusions, 10 chronic non-specific pleurisy, 19 tuberculous pleurisy, 16 parapneumonic effusion and one Dressler Syndrome. When these sub-groups were compared, the parapneumonic effusion subgroup CRP levels (mean 89 +/- 16.3 mg l(-1)) were significantly higher than those in the other subgroups, other exudate of neoplastic effusion, tuberculous pleurisy and chronic non-specific effusion and the transudate group (P<0.0001; P<0.0001; P<0.0004 and P<0.0001, respectively). The ratio between pleural fluid and serum CRP was significantly higher in the parapneumonic effusion subgroup than in the neoplastic subgroup (P<0.0002; 6.6 +/- 2.7 mg l(-1) and 1 +/- 0.2 mg l(-1), respectively). Pleural fluid CRP levels > 30 mg l(-1) had a high sensitivity (93.7%) and specificity (76.5%) and a positive predictive value of 98.4%. In the differential diagnosis of pleural effusions, higher CRP levels may prove to be a rapid, practical and accurate method of differentiating parapneumonic effusions from other exudate types. Although the high level of CRP obtained in the exudate group may be due to the number of patients with parapneumonic effusion who were included, the pleural CRP level may also be helpful in discriminating between exudative and transudative pleural effusions.  相似文献   
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