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121.
半导体红外激光光凝治疗视网膜静脉阻塞   总被引:7,自引:0,他引:7  
为探讨半导体红外激光对视网膜静脉阻塞(RVO)的治疗效果,对58例RVO患者用Keeler公司“Microlase”半导体激光器(波长810nm)作区域封闭或全视网膜光凝(PRP)。结果:17例中央视网膜静脉阻塞(CRVO)患者,治疗前后平均视力分别为0.175及0.40;7例半球阻塞(Semi-CRVO)患者治疗前后平均视力为0.116及0.40;34例视网膜分枝静脉阻塞(BRVO)患者则分别为0.19及0.465。经t检验,差别均有显著性。结论:激光光凝治疗是RVO重建供氧平衡的重要手段,疗效肯定。半导体红外激光有比氩激光更易穿透浑浊介质和更少影响视网膜神经纤维层和黄斑功能等优点。早期进行区域封闭或全视网膜光凝,有利于保存有用视力。  相似文献   
122.
We followed up 107 patients experiencing a first-ever ischemic stroke after having been affected by essential hypertension for at least one year, in order to analyze the phenomenon of post-stroke blood pressure lowering. Of the 82 patients still surviving after three months of follow-up, 44 (54%) had normal arterial blood pressure values. There were no significant differences between these normotensive patients and the 38 with high blood pressure in terms of cerebrovascular risk factors or disability, but blood pressure normalized in 34 of the 54 patients experiencing a carotid stroke (63%) and in only 10 of the 28 experiencing vertebrobasilar stroke (36%) (p=0.035). These data may offer a starting point for further studies of the neurogenesis of arterial hypertension.
Sommario Al fine di analizzare il fenomeno della normalizzazione della pressione arteriosa dopo ictus cerebrale in pazienti prima ipertesi, abbiamo osservato 107 soggetti con primo ictus ischemico, che erano già precedentemente affetti da ipertensione arteriosa da almeno un anno. Degli 82 (77%) sopravvissuti a tre mesi di follow-up, 44 (54%) hanno mostrato una normalizzazione della pressione arteriosa. L'incidenza di fattori di rischio per malattia cerebrovascolare e disabilità grave non è risultata significativamente diversa nel gruppo degli ipertesi rispetto ai normotesi. Tuttavia la normalizzazione della pressione arteriosa è stata osservata in 34 dei 54 pazienti con ictus carotideo (63%) e solo in 10 dei 28 con ictus vertebrobasilare (36%) (p=0.035). Riteniamo che tali dati offrano uno spunto per ulteriori ricerche sulla genesi neurogena dell'ipertensione arteriosa essenziale.
  相似文献   
123.
Summary Ischemic injury was produced in the dog heart by occluding the left anterior descending coronary artery just below the second diagonal branch for a duration of 1.5 h followed by the release of occlusion. Nisoldipine, 3.5 g/kg was injected intravenously 10 min before the occlusion and again 10 min before the commencement of reperfusion. The activity of serum creatine phosphokinase greatly increased after the reperfusion, and this increase was significantly suppressed by Nisoldipine. This drug, in addition, prevented ischemia-induced myocardial hemorrhage and premature ventricular contraction. Sarcolemmal membrane vesicles were prepared from an ischemic and non-ischemic portions of the myocardium 3 h after the commencement of reflow. The fraction was purified approximately 12-fold with respect to ouabain-sensitive (Na+K+)-ATPase as an indicator; contamination of mitochondria was minimum with cytochrome c oxidase as an indicator. Without treatment of Nisoldipine, the total amount of sarcolemmal phospholipid obtained from the ischemic area, as well as the amounts of phosphatidyl-choline and phosphatidyl-ethanolamine, were significantly decreased as compared with those obtained from the non-ischemic area. Nisoldipine treatment abolished the decrease in the sarcolemmal phospholipids, total as well as phosphatidyl-choline and-ethanolamine, induced by ischemia plus reperfusion. Therefore, our work indicates that the Ca++ channel antagonist, Nisoldipine, suppresses the ischemia-induced increase in phospholipid breakdown of cardiac sarcolemma probably through its inhibitory effect on the Ca++-mediated activation of membrane phospholipase, through its vasodilatory action, or both.  相似文献   
124.
Summary The effects of carotid occlusion on the release of catecholamines in the nucleus of the solitary tract (NTS) were investigated in anaesthetized cats. Two aspects of the nucleus (rostral or intermediate NTS) were superfused bilaterally through push-pull cannulae with artificial CSF and the release of the endogenous dopamine, noradrenaline and adrenaline was determined in the superfusate radioenzymatically. The superfusion rate was 150 l/min or 800 l/min. In some experiments, superfusion of the intermediate NTS was carried out after denervation of the aortic arch.In the rostral NTS superfused at a rate of 150 l/min, bilateral carotid occlusion led to a rise in blood pressure and decreased the release rate of dopamine. These changes continued after occlusion termination. The release rate of noradrenaline was transiently diminished during occlusion. The release of this amine was also decreased after occlusion termination. The release rate of adrenaline was not influenced during carotid occlusion, but it was found to be diminished after termination of the occlusion. Superfusion of the rostral NTS at a rate of 800 l/min also reduced the release rate of adrenaline after termination of carotid artery occlusion. In the intermediate NTS (superfusion rate 150 l/min) similar effects of the carotid occlusion on the release rates of dopamine and noradrenaline were observed. In this aspect of the NTS, denervation of the aortic arch abolished the decrease in the noradrenaline release during carotic occlusion, while the release rates of dopamine and adrenaline were decreased during and after termination of the carotid occlusion.The results suggest that (a) the rise in blood pressure in the carotid sinus after termination of a carotid occlusion decreases the release rates of noradrenaline and adrenaline in the NTS, (b) the decrease in the release of noradrenaline during carotid occlusion is due to impulses originating from the baroreceptors of the aortic arch.Thus, impulses from carotid sinus and aortic arch modify the release rates of noradrenaline in the NTS so as to counteract blood pressure changes.Supported by the Fonds zur Förderung der wissenschaftlichen Forschung Send offprint requests to A. Philippu at the above address  相似文献   
125.
Balloon occlusion is the accepted treatment for direct post-traumatic caroticocavernous fistula. We present a case of bilateral traumatic fistulae associated with a pseudoaneurysm. Resolution of both fistulae occurred following treatment of one of them by balloon occlusion of the internal carotid artery. This case highlights the importance of considering a more conservative approach to bilateral fistulae or those associated with a pseudoaneurysm. We review other treatment options. Received: 1 October 1999/Accepted: 20 October 1999  相似文献   
126.
重组竹叶青蛇毒纤溶酶原激活剂TSV-PA体内溶栓效应观察   总被引:4,自引:0,他引:4  
目的:观察重组竹叶青蛇毒纤溶酶原激活剂TSV—PA体内溶栓效应。方法:利用家兔制备的脑血栓模型,以生理盐水和尿激酶为对照,用数字减影血管造影技术观察重组竹叶青蛇毒纤溶酶原激活剂TSV—PA体内溶栓效果。结果:TSV—PA高剂量实验组(300μg/kg)再道时间为2h以内,TSV—PA低剂量实验组(150μg/kg)5h以内再通。尿激酶组(2000U/kg)再通时间为3—6h;24h以内生理盐水对照组没有观察到再通现象。实验动物45h后处死解剖,未观察到出血现象和其它异常现象。结论:重组TSV—PA在体内具有良好的溶栓活性。  相似文献   
127.
目的:比较甘西鼠尾草和丹参两种注射液对大鼠急性脑缺血的影响,并对其作用机理进行探讨。方法:采用大脑中动脉阻断术(MCAO)制作大鼠急性脑缺血模型。采用计算机图像分析仪测定脑梗死的体积,TBA比色法测定血清MDA含量,放免法测定血清SOD含量;电子自旋共振(ESR)法测定药物对羟自由基的清除作用。结果:甘西鼠尾草注射液和丹参注射液均可明显减小急性脑缺血大鼠脑梗死体积,降低血清MDA含量,升高血清SOD含量,体外清除羟自由基的作用甘西鼠尾草强于丹参。结论:甘西鼠尾草和丹参两种注射液作用基本相同。提示甘西鼠尾草有可能成为丹参的代用品。  相似文献   
128.
妊高征并发脑血管疾病7例分析   总被引:5,自引:0,他引:5  
目的 :了解妊高征并发脑血管疾病的临床表现 ,探讨其诊断要点及治疗原则。方法 :回顾性分析我院 2 0 0 0年 1月至 2 0 0 2年 1月发生的 7例脑血管疾病的临床表现及结局。结果 :7例发生脑出血、颅内静脉 (窦 )血栓形成、短暂性脑缺血、蛛网膜下腔出血。结论 :围产期妊高征患者易发生脑血管疾病 ,子痫患者比先兆子痫患者更易发生脑血管疾病  相似文献   
129.
In accordance with the feature of apoplectic dysarthria, it is divided into three types of labial pattern, lingual pattern and laryngeal pattern. The therapeutic methods are respectively explained with case examples. Translator: HUANG Guo-qi  相似文献   
130.
Catheter ablation in children requires placement of multiple large femoral venous sheaths and catheters. Magnetic resonance angiography (MRA) was used to evaluate the effect of indwelling lines on femoral venous blood flow. Between October 1993 and February 1994 a total of 17 patients scheduled for catheter ablation underwent venous MRA. Two-dimensional time-of-flight MRA was performed 12–70 hours after catheterization on all patients. All patients received intravenous heparin during the procedure and had aspirin therapy instituted after ablation. Eighteen catheter ablations and MRA studies were performed on the 17 patients (one patient underwent repeat ablation). There were 7 females and 10 males, with a mean age of 14.8 ± 4.2 years (range 8–21 years). Patients had three venous sheaths inserted in the left femoral vein (5F, 6F, and 7F with external diameters measuring 1.7, 2.0, and 2.3 mm, respectively) and one sheath in the right femoral vein (7F). Four patients (22%) had altered venous flow (two complete obstructions and two partial obstructions) following catheterization. None of these patients experienced symptoms or complications. It was concluded that there is an increased incidence (22%) of venous obstruction following catheter ablation, but there are no related complications. Venous MRA provides a rapid, noninvasive method for evaluating venous flow abnormalities and possibly detects patients at risk for complications.  相似文献   
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