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71.
Johannes Woitzik Elke Lassel Ulf C. Schneider Helmut Schroeck Rudolf Graf 《Experimental neurology》2009,218(1):41-350
Lesion evolution during focal cerebral ischemia may depend on flow restrictions or on accumulation of toxic mediators within the infarct and expansion of these factors to the periinfarct region. So far, the precise contribution of flow dependent versus spreading-mediated impairment of viable periinfarct tissue has not been determined. Therefore, we measured lesion expansion, flow restrictions and glutamate distribution on serial brain sections at different time points after experimental focal ischemia.Permanent focal ischemia was induced by occlusion of the right middle cerebral artery in male rats and the flow reduction was subsequently measured at 1, 12 and 24 h using iodo[14C]antipyrine autoradiography. Additionally, the necrotic volume was determined on serial brain sections and the glutamate content was measured in tissue samples from adjacent microdissections.Twelve hours after focal ischemia no noteworthy viable areas with blood flow restrictions of 20-40 ml 100 g− 1 min− 1 existed but at 24 h the necrotic tissue exceeded the hemodynamically compromised region by 40 ± 21 mm3 (24%). Furthermore, at 12 and 24 h the glutamate content was elevated in areas surrounding the infarct.Relevant flow restrictions are detectable only during early stages of infarct maturation, whereas the propagation of secondary factors may be the predominant mechanism for delayed infarct evolution. 相似文献
72.
Marta Méndez-López Magdalena Méndez Fernando Sánchez-Patán Isabel Casado Maria-Angeles Aller Laudino López Maria-Teresa Corcuera Maria-Jose Alonso Maria-Paz Nava Jaime Arias Jorge-Luis Arias 《Journal of gastrointestinal surgery》2007,11(2):187-194
To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations. 相似文献
73.
74.
S. Aslanyan C. J. Weir C. S. Johnston M. Krams A. P. Grieve K. R. Lees 《European journal of neurology》2007,14(1):1-6
We sought to simultaneously confirm that substantial recovery at day 1 and day 7 after acute ischaemic stroke onset is associated with subsequent neurological deterioration in patients of the Acute Stroke Therapy by Inhibition of Neutrophils randomized clinical trial. Substantial recovery was assessed by improvement in the National Institutes of Health Stroke Score (NIHSS). Neurological deterioration was defined as any stroke event or NIHSS worsening from recovery assessment to day 90. After adjusting for age, t-PA and day 1 NIHSS, there was a non-significant tendency of substantial (pre-specified as 75%) recovery at day 1 to be associated with later deterioration [odds ratio (OR) 2.47; 95% CI, 0.95–6.50]. The corresponding OR for substantial (pre-defined as 65%) recovery at day 7 was 1.84 (0.85–3.96). Other thresholds for recovery were significantly associated with later deterioration: >50%, 80%, 90% and 100% for day 1 and >50%, 60%, 70%, 90% and 100% for day 7. The effect of recovery at day 1 was more important than that of later recovery. This study confirms the association between recovery and subsequent neurological deterioration and is the first to indicate the greater importance of acute recovery at day 1 in comparison with later recovery. 相似文献
75.
Choroid plexus papillomas (CPPs) are typically considered as benign tumors, with a favorable long-term prognosis. Drop metastasis of CPP into the spinal subarachnoid space is rare. We report a 42-year-old woman who presented with headache and back pain 6 years after removal of a posterior fossa CPP. Magnetic resonance imaging revealed mass lesions in the lumbosacral subarachnoid space and recurrent intracranial tumor. The lesions were resected and histologically diagnosed was CPP. We consider that CPP can spread via cerebrospinal fluid pathways and cause spinal drop metastasis. Therefore, it is necessary to evaluate the whole spinal axis and to perform periodic follow-up examinations in patients with CPP. 相似文献
76.
眼底动脉硬化与血压、血糖、血脂的多元分析与评估 总被引:1,自引:0,他引:1
目的探讨眼底动脉硬化与血压、血脂、血糖的相关性,评估中风危险度。方法对2004年5月至2008年10月就诊的患者335例,作为观察组,并与无症状的健康体检者180例作对照,动态检测眼底动脉硬化、血压、血糖、血脂的异常变化,并做综合量化评估。结果脑血管疾病与眼底动脉硬化、血压、血糖、血脂等因素密切相关。结论眼底动脉硬化、血糖、血脂、血压异常的量化评分,能够预估中风,以便采取预防性治疗。 相似文献
77.
目的 探讨腮腺手术中耳大神经后支保留的可行性、方法及临床价值。方法 我们对48例腮腺肿瘤患者,按常规隐蔽切口腮腺手术方法进行治疗,保留或不保留耳大神经后支。分别于术后10d及1、6、12个月进行随访,检测耳廓上部、耳垂、耳下区、耳前区和耳后区的触觉、痛觉,并观察其感觉变化情况。结果 48例中35例耳大神经后支保留,耳廓上部及耳后区感觉无减退。术后早期耳前、耳垂及耳下区感觉有不同程度的减退,以耳前区最明显,随着时间延长症状逐步好转,6个月时感觉接近正常。另13例耳大神经切断患者感觉减退症状更加明显,恢复时间延长。结论 腮腺手术中耳大神经后支保留是可行的,所采用的方法可靠,可减轻局部麻木感,提高患者术后早期生活质量,降低神经切断后产生局部永久性麻木的可能性。 相似文献
78.
目的对比研究动脉血质子自旋标记(ASL)与动态磁敏感对比(DSC)MRI在急性脑缺血诊断中的应用价值。方法27例发病3d内的急性脑卒中患者,均采用3.0TMR行脉冲式ASL和DSCMR检查。观察2种技术的灌注表现,包括灌注不足、正常灌注、延迟灌注、过度灌注等,采用Mann—Whitney检验做定性分析。在扩散加权成像显示的病变部位及对侧正常半球的镜像区域分别确定3个感兴趣区(ROI),测量信号强度并计算信号强度比(病侧/对照侧),并将结果做配对t检验。结果定性分析显示27例患者中,2l例2种技术检查结果一致(灌注不足14例,正常灌注5例,过度灌注2例)。6例2种技术不一致,其中4例ASL显示灌注不足而DSC显示延迟灌注,2例ASL显示正常灌注而DSC显示延迟灌注,两者间差异无统计学意义(P〉0.05)。定量分析示,2种技术的病侧与对照侧信号强度比值ASL为0.7l±0.46,DSC为0.73±0.42,两者间差异无统计学意义(P〉0.05)。结论无创性ASL技术在检测灌注异常时与DSCMRI有相似的敏感性;ASL可与常规MR检查相结合,为临床诊断急性缺血性卒中提供有价值的信息。 相似文献
79.
中风毒邪论是一种与传统中医中风病理有所不同的理论 ,在中风毒邪论指导下形成解毒通络方是较为理想的神经保护剂 ,可解决目前神经保护治疗的主要障碍 ,有望成为提高中医治疗中风急性期疗效的关键 相似文献
80.
关节镜下可吸收螺钉固定腘绳肌重建膝后交叉韧带的疗效评价 总被引:1,自引:0,他引:1
目的 探讨关节镜下可吸收螺钉固定腘绳肌腱单束重建膝后交叉韧带(posterior cruciate ligament,PCL)的效果.方法 2004年4月~2005年4月,我院25例(25膝)经关节镜检查证实为PCL断裂,在关节镜下行自体腘绳肌腱单束PCL 重建术,生物可吸收挤压螺钉解剖位固定重建韧带. 结果 手术时间平均90min(80~100min).25例膝术毕PCL重建后后抽屉试验均为阴性.术后住院时间7~14 d,平均10.4 d.25例术后随访12~24个月,平均18个月,23例膝后抽屉试验阴性,2例后抽屉试验1级.术后12个月Lysholm膝关节功能评分由术前(44.8±8.1)分提高至(77.8±6.4)分(t=-15.999,P=0.000).按国际膝关节文件编制委员会膝关节标准评价膝关节功能分级,术前异常(C级)10例、显著异常(D级)15例,随访时正常(A级)8例、接近正常(B级)15例、异常(C级)2例(Z=-4.394,P=0.000). 结论 关节镜下可吸收螺钉固定自体腘绳肌腱单束重建膝PCL创伤小,固定可靠,手术操作简单,术后膝关节功能恢复效果好. 相似文献