Objective： To determine whether spinal cord decompression plays a role in neural cell apoptosis after spinal cord injury. Study design： We used an animal model of compressive spinal cord injury with incomplete parap...Objective： To determine whether spinal cord decompression plays a role in neural cell apoptosis after spinal cord injury. Study design： We used an animal model of compressive spinal cord injury with incomplete paraparesis to evaluate neural cell apoptosis after decompression. Apoptosis and cellular damage were assessed by staining with terminal deoxynucleotidyl transferase （TdT）-mediated deoxyuridine triphosphate nick-end labelling （TUNEL） and immunostaining for caspase-3, Bcl-2 and Bax. Methods： Experiments were conducted in male Sprague-Dawley rats （n-78） weighing 300-400 g. The spinal cord was compressed posteriorly at T10 level using a custom-made screw for 6 h, 24 h or continuously, followed by decompression by removal of the screw. The rats were sacrificed on Day I or 3 or in Week 1 or 4 post-decompression. The spinal cord was removed en bloc and examined at lesion site, rostral site and caudal site （7.5 mm away from the lesion）. Results： The numbers of TUNEL-positive cells were significantly lower at the site of decompression on Day 1, and also at the rostral and caudal sites between Day 3 and Week 4 post-decompression, compared with the persistently compressed group. The numbers of cells between Day 1 and Week 4 were immunoreactive to caspase-3 and B-cell lymphoma-2 （Bcl-2）-associated X-protein （Bax）, but not to Bcl-2, correlated with those of TUNEL-positive cells. Conclusion： Our results suggest that decompression reduces neural cell apoptosis following spinal cord injury.展开更多
国际物品编码组织(GS1)发布的《GS1数字链接标准:URI语法》(GS1 Digital Link Standard:URI Syntax)对GS1 Digital Link URI的语法结构作了修订。本文对该标准中规定的GS1标识关键字、GS1关键字限定符、相关数据属性以及编码方式进行深...国际物品编码组织(GS1)发布的《GS1数字链接标准:URI语法》(GS1 Digital Link Standard:URI Syntax)对GS1 Digital Link URI的语法结构作了修订。本文对该标准中规定的GS1标识关键字、GS1关键字限定符、相关数据属性以及编码方式进行深入剖析,并列举了不同场景下的应用实例。展开更多
近10年来广州城市显著扩张,为了考察其扩张是否加剧了广州的城市热岛效应,研究以Landsat卫星的热红外影像为数据源,通过反演地表温度,计算城市热岛比例指数(Urban-Heat-Island Ratio Index,URI),并耦合气象数据分别计算国际和国内高温...近10年来广州城市显著扩张,为了考察其扩张是否加剧了广州的城市热岛效应,研究以Landsat卫星的热红外影像为数据源,通过反演地表温度,计算城市热岛比例指数(Urban-Heat-Island Ratio Index,URI),并耦合气象数据分别计算国际和国内高温热浪指数来分析广州市2011~2022年间的城市热岛时空变化,探索卫星热红外数据和高温热浪数据协同研究城市热岛效应的可能性。结果表明:①2011~2022年,广州城市热岛范围与城市建成区空间扩展范围基本一致,都以中部老城区为中心向南北方向扩展。②广州城市热岛比例指数在2011~2022年期间并没有明显上升,这是由于广州开展了为城市降温的“酷城行动”,使其城市热岛效应得到了有效控制。③对比国内、国际的高温热浪指数发现,国内的高温热浪指数更适合广州的具体情况,其与遥感URI指数的协同使用能够更合理地解释广州的城市热岛变化。展开更多
基金Project (No. Y207216) supported by the Natural Science Foundation of Zhejiang Province, China
文摘Objective： To determine whether spinal cord decompression plays a role in neural cell apoptosis after spinal cord injury. Study design： We used an animal model of compressive spinal cord injury with incomplete paraparesis to evaluate neural cell apoptosis after decompression. Apoptosis and cellular damage were assessed by staining with terminal deoxynucleotidyl transferase （TdT）-mediated deoxyuridine triphosphate nick-end labelling （TUNEL） and immunostaining for caspase-3, Bcl-2 and Bax. Methods： Experiments were conducted in male Sprague-Dawley rats （n-78） weighing 300-400 g. The spinal cord was compressed posteriorly at T10 level using a custom-made screw for 6 h, 24 h or continuously, followed by decompression by removal of the screw. The rats were sacrificed on Day I or 3 or in Week 1 or 4 post-decompression. The spinal cord was removed en bloc and examined at lesion site, rostral site and caudal site （7.5 mm away from the lesion）. Results： The numbers of TUNEL-positive cells were significantly lower at the site of decompression on Day 1, and also at the rostral and caudal sites between Day 3 and Week 4 post-decompression, compared with the persistently compressed group. The numbers of cells between Day 1 and Week 4 were immunoreactive to caspase-3 and B-cell lymphoma-2 （Bcl-2）-associated X-protein （Bax）, but not to Bcl-2, correlated with those of TUNEL-positive cells. Conclusion： Our results suggest that decompression reduces neural cell apoptosis following spinal cord injury.
文摘国际物品编码组织(GS1)发布的《GS1数字链接标准:URI语法》(GS1 Digital Link Standard:URI Syntax)对GS1 Digital Link URI的语法结构作了修订。本文对该标准中规定的GS1标识关键字、GS1关键字限定符、相关数据属性以及编码方式进行深入剖析,并列举了不同场景下的应用实例。
文摘近10年来广州城市显著扩张,为了考察其扩张是否加剧了广州的城市热岛效应,研究以Landsat卫星的热红外影像为数据源,通过反演地表温度,计算城市热岛比例指数(Urban-Heat-Island Ratio Index,URI),并耦合气象数据分别计算国际和国内高温热浪指数来分析广州市2011~2022年间的城市热岛时空变化,探索卫星热红外数据和高温热浪数据协同研究城市热岛效应的可能性。结果表明:①2011~2022年,广州城市热岛范围与城市建成区空间扩展范围基本一致,都以中部老城区为中心向南北方向扩展。②广州城市热岛比例指数在2011~2022年期间并没有明显上升,这是由于广州开展了为城市降温的“酷城行动”,使其城市热岛效应得到了有效控制。③对比国内、国际的高温热浪指数发现,国内的高温热浪指数更适合广州的具体情况,其与遥感URI指数的协同使用能够更合理地解释广州的城市热岛变化。
