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81.
C-fos immunoreactivity was used to reveal brain areas in which neurons were influenced by electrical stimulations applied to the dorsal periaqueductal gray. These stimulations were applied in freely moving rats so that the resulting behaviors could be observed. Shortly afterwards, the brains of the rats were processed for C-fos immunoreactivity. In order to determine the specificity of the brain areas thus labeled, control stimulations were applied to the ventral tegmental area of other rats. Immunoreactive cells were found surrounding the tip of the stimulation electrode within a radius of 0.5 mm. This labeled area extended further along the rostro-caudal axis than along the medio-lateral or dorso-ventral axis in the periaqueductal gray. Distally, clusters of labeled cells were found ipsilaterally in the caudal periaqueductal gray extending to the nucleus cuneiformis, and bilaterally in the locus coeruleus and supramamillary decussation. More widespread labeling was found in most hypothalamic subareas and in the lateral habenula. The labeled brain areas following ventral tegmental area stimulations were totally distinct, and comprised the medial forebrain bundle, the nucleus accumbens, the vertical limb of the diagonal band and the medial septum. The pattern of labeling produced by periaqueductal gray stimulations was therefore specific, and provided information about brain structures involved in the motivational and behavioral effects of such stimulations.  相似文献   
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OBJECTIVE: The objective of this study is to evaluate the inflammatory response caused by endovascular stents in the treatment of aortic aneurysms. METHODS: Twenty-five patients underwent endovascular stent treatment from March through December 2005. The evolution of mediators (sedimentation velocity, C reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha, intercellular adhesion molecule-1, l-selectin), inflammatory cells (leukocytes, lymphocytes, platelets), serum creatinine and body temperature within preoperative period and in the following postoperative periods--1, 6, 24 and 48 h, 7 days, 1-3 months, was analyzed. In order to achieve statistic significance, Friedman test and Wilcoxon test were used, with index of significance of 5% (p<0.05). RESULTS: Peak values of sedimentation velocity, C reactive protein and interleukin-6 were observed at 7 days (p<0.0001), 48 h (p<0.0001) and 24h (p<0.0001), respectively. Tumor necrosis factor-alpha and interleukin-8 did not show statistically significant variability during the entire follow-up. In terms of intercellular adhesion molecule-1 and l-selectin, their expressive values were found in late phase of follow-up, although without statistical significance. Elevation of leukocytes count occurred in premature phase of follow-up (p<0.0001), while lymphocyte and platelet count occurred in a late phase of follow-up (p<0.0001). Serum levels of creatinine did not show significant variability during follow-up. The period between 24 and 48 h corresponded to major frequency for fever (p<0.0001). CONCLUSION: Individual mediators analysis and inflammatory cells demonstrated variability of their values during postoperative follow-up. This could help in the analysis of the inflammatory response evolution caused by endovascular stent treatment for aortic aneurysms in premature and late phases after implantation of the vascular prosthesis.  相似文献   
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Patients who underwent isolated aortic valve replacement could come to attention for new onset aortic disease or progression of borderline alterations not corrected at the first operation, especially in the subset of bicuspid valve disease. We describe our technique in redo operations for aortic root disease, using only a vascular graft and sparing the previously implanted valve prosthesis. In case of normally functioning mechanical prosthesis, we always left the valve in situ and substituted the aortic root with a Dacron conduit, extending the replacement if necessary to the other diseased portions of the thoracic aorta.  相似文献   
86.
微创穿刺术治疗基底节区脑出血临床随机对照研究   总被引:50,自引:3,他引:47  
目的评价比较微创穿刺血肿粉碎清除术与内科保守治疗两种方法治疗基底节区脑出血(25~40m l)的疗效异同。方法采用多中心、随机对照试验的方法,42个参研医院共随机入选465例基底节区脑出血患者,根据纳入与排除标准共排除88例,其中资料不全者16例;不符合入选标准者72例,分别为Glasgow评分≤8分(64例)、术前出血量>40m l(7例)、从发病到达急诊室时间>72h(1例)。评价治疗14d时两组患者神经功能缺损程度和日常生活活动能力、治疗3个月时的日常生活活动能力以及3个月和住院期间病死率。结果最终符合入组标准的病例数为377例,其中微创治疗组195例,对照组182例。微创治疗组患者于治疗14d时,神经功能改善明显优于对照组(χ2=7.931,P=0.02);治疗3个月时达良好功能状态的患者比例明显多于对照组(35.91%vs21.82%;χ2=8.294P=0.004)。微创治疗组病,残率明显低于对照组(40.88%vs63.03%,χ2=16.948,P<0.01);两组病死率间差异无显著性意义(6.67%vs8.79%)。结论与单纯内科保守治疗相比,应用微创穿刺血肿粉碎清除术治疗基底节区小血肿不增加病死率,并可明显提高脑出血患者的日常生活活动能力,降低病残率。  相似文献   
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Objective: Endothelial dysfunction represents a critical early component of organ injury following cardiopulmonary bypass. Recent studies demonstrate that the treatment with atorvastatin is associated with a significant improvement of endothelial function independently of its efficacy on cholesterol levels. Therefore, we investigated the effects of preoperative atorvastatin treatment on endothelium function after coronary surgery. Methods: Forty patients undergoing coronary surgery were randomized to treatment with atorvastatin (20 mg/die; N = 20) or placebo (N = 20) 3 weeks before surgery. Twenty normal patients served as control group. The flow-mediated dilations (FMD) of the brachial artery after both reactive hyperemia (endothelium dependent) and nitroglycerin administration (endothelium independent) were evaluated at baseline, at 48 h, and 5 days postoperatively. Results: At baseline, the endothelium-dependent FMD was significantly attenuated in coronary versus normal patients (normal 10.3 ± 1.8% vs coronary 4.1 ± 1.6%, p < 0.01). At 48 h postoperatively all patients exhibited a reduced FMD compared with baseline values: the endothelium-dependent dilatation showed a drop of 60.1 + 15% in the patients of the placebo group compared with 45.8 + 16.6% (p < 0.05) those in the atorvastatin group. At the univariate analysis, no significant correlation was found between serum levels of either total cholesterol or HDL cholesterol and FMD. The nitroglycerin-induced dilation was not significantly influenced by extracorporeal circulation as well as by atorvastatin treatment. Conclusions: The endothelial dysfunction following cardiopulmonary bypass is improved by the treatment with atorvastatin, by a mechanism unrelated to the drug efficacy of controlling serum cholesterol levels.  相似文献   
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Catechol-O-methyltransferase (COMT, EC 2.1.1.6) plays a central role in the metabolic inactivation of neurotransmitters and neuroactive xenobiotics possessing a catechol motif. 1-(3,4-Dihydroxy-5-nitrophenyl)-2-phenyl-ethanone (BIA 3-202) is a novel nitrocatechol-type inhibitor of COMT, the potential clinical benefit of which is currently being evaluated in the treatment of Parkinson's disease. In the present work we characterize the molecular interactions of BIA 3-202 within the active site of COMT and discuss their implication on the regioselectivity of metabolic O-methylation. Unrestrained flexible-docking simulations suggest that the solution structure of this complex is better described as an ensemble of alternative binding modes, in contrast to the well defined bound configuration revealed by the X-ray structures of related nitrocatechol inhibitors, co-crystallized with COMT. The docking results wherein presented are well supported by experimental evidence, where the pattern of in vitro enzymatic O-methylation and O-demethylation reactions are analyzed. We propose a plausible explanation for the paradoxical in vivo regioselectivity of O-methylation of BIA 3-202, as well as of its related COMT inhibitor tolcapone. Both compounds undergo in vivo O-methylation by COMT at either meta or para catechol hydroxyl groups. However, results herein presented suggest that, in a subsequent step, the p-O-methyl derivatives are selectively demethylated by a microsomal enzyme system. The overall balance is the accumulation of the m-O-methylated metabolites over the para-regioisomers. The implications for the general recognition of nitrocatechol-type inhibitors by COMT and the regioselectivity of their metabolic O-methylation are discussed.  相似文献   
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