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排序方式: 共有1113条查询结果,搜索用时 15 毫秒
11.
目的研究体外培养星形细胞牵张损伤后超微结构的变化。方法取新生1~2 d大鼠的皮层细胞原代培养,经纯化后传代培养于乳胶膜培养皿中。采用计算机控制的牵张损伤装置,分别以50、150、250 kPa压力牵张损伤培养于乳胶膜上的大鼠皮层星形胶质细胞。用3%戊二醛固定后,行扫描电镜和透射电镜观察。结果当用50 kPa驱动压力进行牵张损伤时,细胞结构即有明显破坏,表现为细胞间隙增宽,部分胞体和突起被撕裂;以50 kPa牵张损伤后1 h,透射电镜下可见线粒体肿胀、嵴减少;损伤后6 h可见线粒体致密、细胞器减少等。当牵张应力增大,星形细胞损伤程度加重,细胞器明显减少,线粒体空泡化,微丝、微管明显减少,直至水样胞质或致密胞体。结论较小的应力即可致星形细胞紧密连接的破坏和超微结构的改变,可能与脑外伤后产生广泛的脑水肿有关。 相似文献
12.
发达社会疾病--创伤 总被引:23,自引:0,他引:23
“病”和“伤”是危害人类健康乃至生命的两大类疾患。近几十年来,医学有了很大的发展,许多疾病已能得到有效的诊治,但创伤却有所不同。一方面,创伤的救治技术有了很大的进步,一些过去认为必死无疑的危重创伤病人也可能救活以至治愈;另一方面,创伤的发生率不断增高,死伤人数逐年上 相似文献
13.
2003年9月14~17日,在匈牙利布达佩斯召开了第19届国际交通医学会议,第三军医大学交通医学研究所的5位教授(王正国、朱佩芳、蒋建新、尹志勇、陈海斌)作为中国代表参加了会议,并作了4次学术报告。我们介绍的中国交通医学基础研究、交通伤院前急救模式探讨、自制的驾驶员在线疲劳测试系统和“应变能密度”用于观测颅脑撞击伤后应力分布的计算机模拟技术等均受到好评。会议期间,国际交通医学会(IAMA)理事会通过决议,选举我为国际交通医学会副主席,负责西亚地区的学会工作。 相似文献
14.
N—乙酰—5—甲氧色胺镇痛作用的实验研究 总被引:5,自引:2,他引:3
目的 为了寻找新型镇痛药物,对N-乙酰-5-甲氧色胺(Mel)的镇痛作用及其与哌替啶(Pt)的协同作用进行探索性研究。方法 采用小鼠热板法及冰乙酸致小鼠扭体为疼痛模型,观察Mel对痛阈的影响。结果 Mel 30,60,120mg/kg剂量依赖性地增加小鼠痛阈,且于给药后1h达高峰,持续至2h仍有效。此外,无镇痛效应的Mel(10mg/kg)与哌替啶(10mg/kg)合用,能明显提高小鼠痛阈。结论 Mel具有良好的镇痛作用,增大剂量完全能达到哌替啶的镇痛效应,且与哌替啶有明显协同效应。 相似文献
15.
Objective: To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure (BUP). Methods : The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses ( ABR). The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells (OHCs) loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. Results: An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa (P<0.01). The rate of perforation of tympanic membrane reached 87.5 % and that of total OHCs loss was 19.46%±5.38% at 14d after exposure. The guinea pigs protected with barrel and earplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection (P<0.01). All of the tympanic membrane and ossicular chain of the protected animals maintained their integrities. Meanwhile, the guinea pigs protected with the barrel had lower ABR threshold and total OHCs loss rate than those with earplug (P<0.01). Conclusions: The earplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug. 相似文献
16.
17.
两种方法对血管内皮细胞回收率影响的比较 总被引:3,自引:1,他引:2
本文比较了明胶沉降法和Percoll密度梯度一步分离法对血管内皮细胞(VEC)回收率的影响,以探寻更加适合于从外周血中获取有活力VEC的实验方法。 相似文献
18.
Vascular endothelial growth factor and its receptor expression during the process of fracture healing 总被引:3,自引:0,他引:3
Objective: To study the expression regularity of vascular endothelial growth factor (VEGF) during the process of fracture healing, and the type of VEGF receptor expressed in the vascular endothelial cells of the fracture site.
Methods: The fracture model was made in the middle part of left radius in 35 rabbits. The specimens from the fracture site were harvested at 8, 24, 72 hours and 1, 3, 5, 8 weeks, and then fixed, decalcified, and sectioned frozenly to detect the expression of VEGF and its receptor at the fracture site by in situ hybridization and immunochemical assays.
Results: VEGF mRNA and VEGF expression was detected in many kinds of cells at the fracture site during 8 hours to 8 weeks after fracture. Fltl receptor of VEGF was found in the vascular endothelial cells at the fracture site during 8 hours to 8 weeks after fracture, and strong expression of flkl receptor was detected from 3 days to 3 weeks after fracture.
Conclusions: The expression of VEGF and fltl receptor appears during the whole course of fracture healing, especially from 1 to 3 weeks. Flkl receptor is highly expressed in a definite period after fracture. VEGF is proved to be involved in the vascular reconstruction and fracture healing. 相似文献
Methods: The fracture model was made in the middle part of left radius in 35 rabbits. The specimens from the fracture site were harvested at 8, 24, 72 hours and 1, 3, 5, 8 weeks, and then fixed, decalcified, and sectioned frozenly to detect the expression of VEGF and its receptor at the fracture site by in situ hybridization and immunochemical assays.
Results: VEGF mRNA and VEGF expression was detected in many kinds of cells at the fracture site during 8 hours to 8 weeks after fracture. Fltl receptor of VEGF was found in the vascular endothelial cells at the fracture site during 8 hours to 8 weeks after fracture, and strong expression of flkl receptor was detected from 3 days to 3 weeks after fracture.
Conclusions: The expression of VEGF and fltl receptor appears during the whole course of fracture healing, especially from 1 to 3 weeks. Flkl receptor is highly expressed in a definite period after fracture. VEGF is proved to be involved in the vascular reconstruction and fracture healing. 相似文献
19.
20.
典型冲击波由超压和负压组成,冲击波超压的致伤作用非常明确,其致伤机理研究得较广泛和深入。一般认为,冲击波负压不具有致伤能力,因为不伴有负压成份的超压亦能造成典型的冲击伤;冲击波负压峰值变化范围小,与超压相比其作用可以忽略。然而,单纯冲击波超压不能释放全部现象,冲击波负压有可 相似文献