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Objective Ependymal cells are thought to be the primary source of neural stem cells in the adult central nervous system. The purpose of this study is to examine spatial and temporal profiles of ependymal cell proliferation and migration after focal cerebral ischemia. Methods Eighty male Sprague Dawley rats underwent permanent middle cerebral artery occlusion after injection of 10/μL of 0.2% Dil into the lateral ventricle. Rats were sacrificed and brain sections were acquired for pathological evaluation and laser confocal imaging at day 1,3,7,11,14,21 and 28 after ischemia. Results The density of Dil-labeled cells in the ischemic ipsilateral subventricular zone was significantly higher than that in the control group and these labeled cells dispersed in the ischemic ipsilateral subventricular zone and/or were located in ependyma from day 1 to 11. In the ischemic ipsilateral cortex, some Diilabeled cells occurred in peri-infarction and infarction of parietal region at day14 and peaked at day 21 when some Dil-labeled cell nodules were found in this region. During postischemic day 14--28, a significant decrease in labeled celldensity in the ischemic ipsilateral subventricular zone was coincident with a significant increase in labeled cells density in the cortex (peri-infarction and infarction). Conclusion The results indicate that ependymal cells proliferate and migrate after focal cerebral ischemia in the adult rat brain. 相似文献
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本文介绍了江苏宁沪高速公路股份有限公司工程养护管理体系及在计划、招标、监理、质量、验收、决算及审计等养护管理工作的主要做法,分析了现有工程养护管理体系及方法存在的问题,提出了进一步深化养护体制改革的几点建议。 相似文献
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针对浅海混响背景下频域自适应匹配滤波器检测性能下降的问题,提出基于分数阶傅里叶变换(FRFT)的频域自适应匹配滤波器检测方法,该方法利用模板匹配技术,采用滑动窗对接收信号进行最优阶次分数阶傅里叶变换,然后将此过程中得到的FRFT域图与参考信号最优阶次傅里叶变换FRFT域图进行匹配,将离差平方和作为评价相似度的指标,即对离差平方和最小值的位置进行滤波,并对滤波后的信号进行最优阶次分数阶傅里叶逆变换,从而实现混响背景下的目标检测。仿真结果表明,在信混比为-15 dB的情况下,该算法可显著提高频域自适应匹配滤波器的检测性能。 相似文献
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发信机做为海岸电台应急通信的关键设备,其稳定可靠和不间断运行是对海上通信业务正常开展的必要前提。针对现有断电切换电存在的空白时间间隙问题,通过分析应用UPS不间断电源改造电源系统,解决了现系统的不足,实现了设备断电零秒切换,保障了安全通信不间断传播。 相似文献
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本文概述了沪宁高速公路江苏段沥青路面的结构组成、通车以来交通量及路面使用性能技术指标变化情况,分析了路面病害特点及成因,并对设计、施工、管理、养护等方面提出了改进建议。 相似文献
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