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The involvement of oxidative stress in polymorphonuclear leukocytes (PMN) in the pathogenesis of hypertension remains to be elucidated. We analyzed the generation of reactive oxygen species (ROS) by the circulating and peritoneally infiltrating PMN from spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). Flow cytometric analysis revealed that ROS generation by PMN from SHR was higher than that from WKY before (at 6 weeks of age) and after (at 16 weeks of age) the onset of hypertension. In vivo, ROS generation by PMN from SHR, but not that by PMN from WKY, was significantly suppressed by 10-week treatment with 50 mg/kg/day carvedilol, and this treatment did not affect blood pressure. Western blotting analysis revealed that protein kinase C alpha (PKCalpha), but not PKCbetaI or betaII, was activated more strongly in PMN from SHR than in PMN from WKY. Furthermore, expression of p47phox of nicotinamide adenine dinucleotide phosphate oxidase, but not of p67phox, in PMN from SHR was higher than that in PMN from WKY. These results suggest that ROS generation by PMN is principally enhanced in SHR through activation of PKCalpha and p47phox.  相似文献   
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There is increasing evidence from human and experimental studies that the most important factor governing the outcome in head injury is the severity of diffuse axonal injuries. The authors have experienced 18 cases of severe diffuse axonal injury which showed post-traumatic coma for more than 24 hours and CT findings resembling those of shearing injuries of the cerebral white matter such as have been presented by Zimmerman et al. (1978). The consciousness levels on admission were 6 or less on the Glasgow Coma Scale and all cases were shown clinically to have primary brain stem injury. The main type of head trauma resulted from road traffic accidents (83%). Skull fractures were found in only 5 cases (28%). These findings suggested that acceleration/deceleration injury produce in the patients severe diffuse axonal injury. Initial ICP was below 20 mmHg in 11 cases out of 13 (85%). Parenchymal small hemorrhagic lesions of initial CT were basal ganglia (7 cases), corpus callosum (4 cases), pons (4 cases), midbrain (3 cases) and thalamus (2 cases). Extraparenchymal hemorrhagic lesions included intraventricular hemorrhage (6 cases) and subarachnoid hemorrhage (6 cases). Two autopsied cases of severe diffuse axonal injury (acute case and chronic case) showed remarkable congestion and edema in the deep part of the frontal white matter. Microscopic examination revealed marked axonal degeneration including axonal retraction ball in the corpus callosum, in the internal capsule and in the white matter of the brain stem. Glasgow Outcome Scale of the 18 patients at 3 months after the trauma made us concerned that no patients indicated good recovery or even only moderate disability.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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OBJECTIVE: A joint study was undertaken by the Japanese Society of Renal Cancer to investigate the present status of partial nephrectomy in Japan and to speculate about what may be the indications for partial nephrectomy in patients with renal cell carcinoma. METHODS: Data were tabulated for 469 patients from participating medical institutions and various clinical factors were investigated with regard to disease progression (local recurrence and distant metastasis). RESULTS: Disease progression was observed in 21 patients (4.5%). No significant relation to disease progression was observed for sex, laterality, tumor histology, grade and tumor size. Although patients with solitary tumors displayed excellent prognosis irrespective of tumor diameter, patients with multiple tumors displayed a high likelihood of disease progression. Patients older than 77 years old and patients with imperative indication were found to have a poorer prognosis. CONCLUSION: In patients with solitary tumors, partial nephrectomy can be actively performed, even if the patient displays elective indications and the tumor is >4 cm in diameter. In patients displaying multiple tumors with imperative indications, the decision whether to perform partial nephrectomy should be made by the patients and their physicians after considering the impact on curability and the quality of life.  相似文献   
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BACKGROUND: Gender differences in the predictors of outcome among patients with known or suspected coronary artery disease (CAD) undergoing contrast-enhanced dobutamine stress echocardiography (CE-DSE) have not been completely determined. METHODS AND RESULTS: Follow-up (30+/-17 months) data for 581 men and 309 women with known or suspected CAD who underwent CE-DSE (mean age: 66 years) were obtained. Hard cardiac events included cardiac death and nonfatal myocardial infarction. Total cardiac events included hard cardiac events, unstable angina, congestive heart failure, and late revascularization (>3 months). Cardiac events occurred in 123 male and 50 female patients. Positive results for CE-DSE were associated with worse prognosis in both men and women (2-year total event free rate: 73.5% vs 88.2% in men, p<0.0001, 80.3% vs 91.3% in women, p<0.01). Addition of CE-DSE results, including abnormal left ventricular end-systolic volume response and left ventricular ejection fraction at peak stress <50%, to the clinical and rest echocardiography model provided incremental information for predicting total cardiac events (increase in chi-square value for the model from 60 to 72, p<0.001) in men and (increase in chi-square value for the model from 17 to 32, p<0.001) in women. CONCLUSIONS: CE-DSE provides incremental information for predicting future cardiac events in both men and women.  相似文献   
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We have used recombinant human erythropoietin (rEPO) in order to prevent patients from developing anemia following preoperative autologous blood preservation. Thereby, we have been able to reduce intraoperative homologous blood transfusion during cardiac operations. In June and July, 1989, six middle-aged selective patients received rEPO (200 IU/kg) intravenously every other day starting from fifteen days before the day of their operations. One unit (200 ml) of autologous blood was drawn and preserved every few days. However, no significant differences were observed in red cell counts, hematocrit, hemoglobin and serum protein levels between before and after preservation. Not only preoperative autologous blood preservation with provision of rEPO, but also using the intraoperative autotransfusion system enabled us to perform cardiac operations on 5 out of 6 patients without any homologous blood transfusion. None of the six patients exhibited any undesirable effects due to rEPO administration. Their postoperative courses were excellent.  相似文献   
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OBJECTIVE: The aortic connector system was used to minimize cerebrovascular complications when performing the proximal anastomosis of vein grafts during coronary artery bypass grafting (CABG). The goal of this study was to investigate the intermediate outcomes of patients undergoing CABG with the aortic connector system. METHODS: The aortic connector was used on nine patients undergoing CABG between November 2002 and July 2003. Intermediate outcomes of the patients were examined, and the results of coronary angiography, which were performed before patient discharge and at least 6 months after discharge, were evaluated. RESULTS: There were no operative deaths or cerebrovascular accidents. One patient died 9 months after discharge, one patient had angina, and the remaining seven patients were asymptomatic. When evaluating the results of angiography performed before patient discharge, two of the 21 distal vein graft anastomoses were occluded (patency rate, 90.5%), but there was no stenosis or occlusion at the proximal anastomoses sites that were performed using the aortic connector. When evaluating the results of the second angiography performed after patient discharge, four of the eight proximal anastomoses were patent, one was completely occluded, two had 90% stenosis and one had 75% stenosis. Further, four of the 18 distal anastomoses were occluded (patency rate, 77.8%). There was no significant difference in graft flow or device size when comparing patients with patent vein grafts and those with stenotic or occluded vein grafts. CONCLUSION: Intermediate outcomes of vein grafting using the aortic connector were suboptimal. Long-term outcome data are forthcoming.  相似文献   
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