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931.
目的:研究冠心病合并脑梗死患者的心率变异性情况,和心律失常的发生率,分析它们的变化规律,为患者疾病的治疗及预后提供更好的治疗指导。方法:研究对象为2012年2月~2012年12月我院心内科及神经内科的患者,其中Ⅰ组:冠心病合并脑梗死患者40例、Ⅱ组:单纯冠心病患者40例、Ⅲ组:单纯脑梗死患者40例、以及Ⅳ组:健康成人50例,统计全部患24 h心率变异性及心律失常发生情况,并进行对比分析。结果:Ⅰ组患者的心率变异性和心律失常发生明显高于其它组患者,差异均具有统计学意义(P〈0.05)。且心率变异性时域参数下降,心律失常发生率升高。结论:冠心病合并脑梗死患者的心率变异性和心律失常发生率增高,为避免冠心病合并脑梗死的患者突然心律失常及猝死,应积极改变治疗措施。 相似文献
932.
功能磁共振成像(fMRI)作为一种无创伤,可反复实验的成像技术,已被广泛地应用于各项脑功能的研究。用fMRI进行脑功能研究的主要依据是血流敏感性和BOLD对比增强原理。记忆是人脑的高级功能,其过程分为编码加工、固化、存储和提取几个阶段。大脑皮质、海马、乳头体、丘脑是参与记忆的主要解剖结构。记忆的刺激方式对各个脑区的激活是具有差异性的,记忆功能的测量和分析方法也在不断的改进。年龄和性别的不同都会对记忆能力产生影响,同时激活的脑区也会有相应的改变。此外,情感和记忆的关系正越来越受到人们的关注。本文阐述利用功能磁共振成像研究记忆功能的最新进展。 相似文献
933.
Enhanced expressions of arachidonic acid-sensitive tandem-pore domain potassium channels in rat experimental acute cerebral ischemia 总被引:1,自引:0,他引:1
Li ZB Zhang HX Li LL Wang XL 《Biochemical and biophysical research communications》2005,327(4):1163-1169
To further explore the pathophysiological significance of arachidonic acid-sensitive potassium channels, RT-PCR and Western blot analysis were used to investigate the expression changes of TREK channels in cortex and hippocampus in rat experimental acute cerebral ischemia in this study. Results showed that TREK-1 and TRAAK mRNA in cortex, TREK-1 and TREK-2 mRNA in hippocampus showed significant increases 2 h after middle cerebral artery occlusion (MCAO). While the mRNA expression levels of the all three channel subtypes increased significantly 24 h after MCAO in cortex and hippocampus. At the same time, the protein expressions of all the three channel proteins showed significant increase 24 h after MCAO in cortex and hippocampus, but only TREK-1 showed increased expression 2 h after MCAO in cortex and hippocampus. Immunohistochemical experiments verified that all the three channel proteins had higher expression levels in cortical and hippocampal neurons 24 h after MCAO. These results suggested a strong correlation between TREK channels and acute cerebral ischemia. TREK channels might provide a neuroprotective mechanism in the pathological process. 相似文献
934.
目的:观察通络救脑注射液对正常及拟缺血大鼠脑微血管内皮细胞的活性影响,并初步探讨细胞条件培养液内蛋白分泌的时效特征、奠定可溶性蛋白深入分析的技术基础。方法:通络救脑注射液作用于正常夏拟缺血脑微血管内皮细胞之后,用MTS/PMS比色分析法测定细胞的活性,Bradford法测定细胞培养液总蛋白含量,比色分析法测定细胞培养液乳酸脱氢酶(LDH)漏出值,同步观察了5个时间点的细胞活性及条件培养液总蛋白量及LDH释放量。结果:通络救脑注射液能够提高拟缺血细胞的活性,且抑制LDH释放量;正常组分泌总蛋白量3h达到高峰,此时细胞活性最佳,LDH释放量亦少。拟缺血组分泌总蛋白量是6h达到高峰,此时LDH释放量最少,但细胞活性与3h比较有所下降。结论:通络救脑注射液对拟缺血细胞损伤具有保护作用:以3h至6h的细胞条件培养液做为收集目标是研究条件培养液的最佳时间段。 相似文献
935.
CCM3/PDCD10 heterodimerizes with germinal center kinase III (GCKIII) proteins using a mechanism analogous to CCM3 homodimerization 总被引:1,自引:0,他引:1
Ceccarelli DF Laister RC Mulligan VK Kean MJ Goudreault M Scott IC Derry WB Chakrabartty A Gingras AC Sicheri F 《The Journal of biological chemistry》2011,286(28):25056-25064
CCM3 mutations give rise to cerebral cavernous malformations (CCMs) of the vasculature through a mechanism that remains unclear. Interaction of CCM3 with the germinal center kinase III (GCKIII) subfamily of Sterile 20 protein kinases, MST4, STK24, and STK25, has been implicated in cardiovascular development in the zebrafish, raising the possibility that dysregulated GCKIII function may contribute to the etiology of CCM disease. Here, we show that the amino-terminal region of CCM3 is necessary and sufficient to bind directly to the C-terminal tail region of GCKIII proteins. This same region of CCM3 was shown previously to mediate homodimerization through the formation of an interdigitated α-helical domain. Sequence conservation and binding studies suggest that CCM3 may preferentially heterodimerize with GCKIII proteins through a manner structurally analogous to that employed for CCM3 homodimerization. 相似文献
936.
Keun-Hwa Jung Kon Chu Soon-Tae Lee Hee-Kwon Park Jin-Hee Kim Kyung-Muk Kang Sang Kun Lee Jae-Kyu Roh 《Biochemical and biophysical research communications》2009,378(3):507-72
Our recent work suggested that early infusion of nitrite might represent a novel therapeutic approach for acute ischemic stroke. In this study, we sought to examine the therapeutic time window of nitrite in an experimental stroke model, and to develop combined strategies for augmenting its protective effects. Nitrite was infused at various times after ischemia to rats subjected to transient or permanent focal ischemia. Nitrite was infused with memantine to prevent the potential toxicity. Infarct volumes, functional outcomes, microhypoxic areas, and oxidative stress were measured. Nitrite reduced the infarction volume and enhanced functional recovery when administered within 3 and 1.5 h in the transient and permanent model, respectively. Combined therapy with nitrite and memantine prolonged the time window up to 4.5 h. The potential oxidative toxicities of nitrite were significantly inhibited by memantine. The combination therapy of nitrite and memantine may be a feasible therapeutic approach for acute ischemic stroke. 相似文献
937.
938.
The Cerebral Microvessels in Culture, an Update 总被引:8,自引:0,他引:8
Ferenc Joó 《Journal of neurochemistry》1992,58(1):1-17
Recent advances in our knowledge of the blood-brain barrier (BBB) have in part been made by studying the properties and function of cerebral endothelial cells in vitro. After an era of working with a fraction, enriched in cerebral microvessels by centrifugation, the next generation of in vitro BBB model systems was introduced, when the conditions for routinely culturing the endothelial cells were established. This review summarizes the results obtained from this rapidly growing field. It can be stated with certainty that, in addition to providing a better insight into the chemical composition of cerebral endothelial cells, much has been learned from these studies about the characteristics of transport processes and cell-to-cell interactions during the last 12 years. With the application of new technologies, the approach offers a new means of investigation, applicable not only to biochemistry and physiology but also to the drug research, and may improve the transport of substances through the BBB. The in vitro approach has been and should remain an excellent model of the BBB to help unravel the complex molecular interactions underlying and regulating the permeability of the cerebral endothelium. 相似文献
939.
目的:研究基于卒中登记的颅内动脉瘤致蛛网膜下腔出血(aneurysmal subarachnoid hemorrhage,a SAH)的颅脑血流动力学改变及其对诊断治疗的指导作用。方法:采用回顾性研究经卒中登记系统筛选出48例经DSA(digital subtraction angiography,DSA)确诊的a SAH,收集患者床旁经颅多普勒(transcranial Doppler,TCD)监测大脑中动脉(middle cerebral artery,MCA)的动脉平均峰值流速(mean blood velocity,Vm)、搏动指数(pulsatility index,PI)、阻力指数(resistance index,RI),自身健侧作为正常对照,均采用血管内介入治疗,对其中符合脑血管痉挛(cerebral vasospasm,CVS)诊断标准的患者使用尼莫地平进行治疗,观察疗效。结果:与健侧相比,患侧PI、RI增大,Vd、Vm减小,其中以Vd减小较明显,与健侧相比有统计学差异(P0.01),Vs与健侧相比无统计学差异(P0.05)。CVS组与非CVS组相比Vm明显增加,有统计学差异(P0.001)。所有患者经水膨胀弹簧圈或支架预后均得到改善。结论:床旁实时TCD监测能反映a SAH脑血流变化,对CVS进行及时解除痉挛治疗,并为介入治疗提供参考依据,颅脑血流实时监测和介入治疗综合运用提高了a SAH患者的治疗效果。 相似文献
940.
Background: CFD has been used to assess intra-aneurysmal hemodynamics. Nevertheless, the lack of patient-specific flow information has triggered the possibility of implementing a wide variety of physiological flow conditions. Due to these uncertainties in the patient flow conditions, the normalization of the intra-aneurysmal hemodynamics is generally conducted. 相似文献