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91.
应用免疫细胞化学技术与图像分析系统研究三七皂苷的免疫药理学机制。正常组大鼠;实验组大鼠(左颈总动脉结扎并于术前4h肌注三七皂苷,7mg.kg~(-1))与对照组大鼠(左颈总动脉结扎用等量生理盐水取代三七皂苷)各分4h组、12h组与24h组。各组鼠大脑皮质、海马与尾壳核内神经元性一氧化氮合酶(nNOS)的含量用LSAB法与计算机数字图像分析系统检测。结果显示对照组大鼠海马、尾壳核与大脑皮质内nNOS含量显著下降,三七皂苷可恢复缺血脑组织的nNOS表达,并对缺血脑组织发挥保护作用。同时,本实验还提示免疫细胞化学技术与图像分析系统用于免疫药理学研究是可行的。  相似文献   
92.
目的探讨一氧化碳中毒合并脑梗塞患者的智能变化.方法对患者仿用智力量表进行检测,严格按操作规程进行,检测期间患者意识清楚,能够合作.数据以(x±s)表示,进行t检验.结果46例病例组比45例对照组测验得分明显减少,尤其是计算力和近记忆力更为明显,有显著性差异(P〈0.01).结论一氧化碳中毒合并脑梗塞患者在恢复期进行智能测评是判断患者智能恢复程度的一项重要指标.  相似文献   
93.
AIM To investigate whether quercetin (Que) attenuates microvascular injury after myocardial ischemia/reperfusion (I/R), and whether its mechanism is related to the up-regulation of silent information regulator 1 (SIRT1). METHODS In vivo, SD rats (220~250 g) were randomly divided into sham group (only threading without ligation), I/R group (ischemia 30 min/reperfusion 60 min), I/R+Que group (10 mg/kg Que injected intravenously 15 min before reperfusion) and I/R+Que+EX527 group (1 mg/kg EX527 injected intravenously 15 min before Que). The protein expression of SIRT1 in each group was determined by Western blot. The effect of Que on the morphological changes of myocardial microvascular was estimated by HE staining. The contents of endothelial damage markers and inflammatory factors in peripheral blood serum of the rats in each group were measured by ELISA. In vitro, Transwell chamber was used to culture H5V cells and then the influence of Que on the permeability of endothelial cells was evaluated. The expression of myosin light chain phosphatase(MLCP), zonula occludens-1 (ZO-1) and cytoskeleton was determined by Western blot and immunofluorescence method. RESULTS The results of Western blot showed that SIRT1 was significantly reduced by I/R in the myocardial tissue. Que increased the expression of SIRT1 after I/R, whereas EX527 significantly inhibited this effect (P<0.05). Que reduced the incidence of I/R arrhythmia, alleviated microvascular damage and inhibited the infiltrating of inflammatory cells,as well as decreased levels of the endothelial injury markers (E-selectin and VCAM-1) and proinflammatory factors (PAF, IL-1α and IL-6). While EX527 significantly reduced these effects of Que by inhibiting SIRT1. Cultured H5V cells showed that hypoxia/reoxygenation resulted in increased permeability of endothelial cells and decreased expression of ZO-1 and MLCP. However, Que, which up-regulated expression of SIRT1, significantly reduced the permeability of endothelial cells significantly and increased the expression of ZO-1 and MLCP. Meanwhile, the cytoskeleton remodeling basically disappeared. EX527, which down-regulated expression of SIRT1, significantly inhibited the above effects of Que. CONCLUSION Que attenuates myocardial I/R induced microvascular injury. The up-regulation of SIRT1 is involved in this mechanism.  相似文献   
94.
AIM:To investigate the effect of dexmedetomidine (DEX) on renal injury induced by lung ischemia/reperfusion (I/R) in mice and its relationship with endoplasmic reticulum stress response.METHODS:Healthy SPF male C57BL/6J mice,weighing 20~24 g,aged 8~10 weeks,were randomly divided into 5 groups (n=10 each):sham operation group (sham group),I/R group,atipamezole (Atip) group,DEX group,and DEX+Atip group.In vivo lung I/R model was established by occlusion of the left pulmonary artery for 30 min followed by 180 min of reperfusion in the mice.The Atip (250 μg/kg),DEX (20 μg/kg) and DEX+Atip were intraperitoneally infused into the mice before left pulmonary hilus was blocked in Atip group,DEX group and DEX+Atip group,and other operations were the same as I/R group.After experiment,the mice were killed,and the renal tissues were harvested to observe the morphological changes.The enzymatic activity of caspase-3,serum creatinine and blood urea nitrogen,and cell apoptotic index of the renal cells were also analyzed.The expression of c-Jun N-terminal kinase (JNK),caspase-12,CCAAT/enhancer-binding protein homdogous protein (CHOP) and glucose-regulated protein 78(GRP78) at mRNA and protein levels in the renal tissues was determined by RT-PCR and Western blot.RESULTS:Compared with sham group,the enzymatic activity of caspase-3,serum creatinine and blood urea nitrogen,renal cell apoptotic index,and the mRNA and protein levels of JNK,caspase-12,CHOP and GRP78 in I/R group were significantly increased (P<0.01),and the renal tissues had obvious damage under light microscope.Compared with I/R group,Atip group and DEX+Atip group,the enzymatic activity of caspase-3,serum creatinine and blood urea nitrogen,renal cell apoptotic index,and the mRNA and protein levels of JNK,caspase-12 and CHOP in DEX group were significantly decreased,and the expression level of GRP78 significantly increased (P<0.01).Furthermore,the renal tissue damage was obvious reduced.CONCLUSION:DEX effectively relieves the renal injury induced by lung I/R in mice,which may be associated with exciting α2-adrenergic receptor and inhibiting endoplasmic reticulum stress response.  相似文献   
95.
AIM and METHOD:To determine the production of nitric oxide(NO) and change of NO synthase(NOS) activity in mitochondria isolated from the rat brains of the ischemia/reperfusion rat model produced by transient occlusion of middle cerebral artery on the following time points:2 h after occlusion of artery and 30 min,2 h, 4h after reperfusion.RESULTS:After the occlusion of middle cerebral artery,the respiratory control rate(RCR) of mitochondria significantly decreased and slightly increased at 4h after reperfusion.Meantime,the production of NO in mitochondria increased significantly.But with the increase of perfusion, production of NO gradually decreased and reached normal level as in the control group.It also shows that cerebral ischemia increased NOS's activity significantly in the mitochondria and still kept a higher level than the control group although it decreased gradually after reperfusion.But the iNOS's activity did not show obvious change.The change of total NOS's activity depends on the change of cNOS's activity.CONCLUSION: The activation of NO/NOS system in the mitochondria might play an important role in the reperfusion injury during reperfusion of ischemic brain.  相似文献   
96.
AIM:To observe the relation between astroglial activation state and ischemic tolerance in the gerbil hippocampus. METHOD: Bilateral occlusion of common carotid arteries and immunofluorescent methods in the gerbil hippocampal tissue. Slices were used. The morphological changes of the neurons were observed by light microscopy.RESULTS:Pretreatment with 2 minute bilateral carotid artery occlusion produced protective effects of CA1 neurons. Glial fibrillary acidic protein (GFAP) staining showed weak positive cells in control group. Most of GFAP positive cells showed weak and middle positive cells after recirculation 1d and 2d following ischemic 3.5 min and preconditioning of the brain with sublethal ischemia respectively.CONCLUSION:Astroglial played an important role in cerebral ischemia. It is possible that state of astroglial activation related to neuronal survival in ischemic tolerance.  相似文献   
97.
AIM:To investigate probable protective mechanism of non-wounded legs ischemic preconditioning on ischemia/reperfusion(I/R) myocardium. METHODS: 36 male SD rats, weighting (250±30) g,were divided into 4 groups.They are normal control(NC);I/R; classical ischemic preconditioning(C-IPC)and non-wounded legs ischemic preconditioning(N-WIPC). NO in plasm,expression of myocardial HSP 70 mRNA, the activities of 5’-NT and CAT of myocardium were observed in all groups. RESULTS:The level of NO in plasm significantly enhanced in groups C-IPC and N-WIPC compared with that in groups I/R and NC ( P <0.01),expression of myocardial HSP 70 mRNA was greatly increased in both C-IPC and N-WIPC groups, the activities of 5’-NT, CAT of myocardium were also raised in groups C-IPC and N-WIPC ( P< 0.05 vs I/R),but there was no difference between C-IPC and N-WIPC( P >0.05). CONCLUSION:The possible protective mechanism involved in N-WIPC is similar to that in C-IPC, which is due to increase of endogenous myocardial protective substances.  相似文献   
98.
AIM:Myocyte apoptosis in rats can be induced by acute ischemia, but time course and distribution of myocyte apoptosis were unclear.METHODS:DNA agarose gel electrophoresis and TdT-mediated dUTP nick end-labling(TUNEL)assay were performed to evaluate apoptosis in mycardium exposed to 45 minutes, 2 hours, 6hours, 12 hours ischemia and sham-operated rats in vivo.RESULTS:DNA ladders were clearly visible in agarosegel of DNA from ischemic myocardium exposed to 2 hours, 6 hours and 12 hours ischemia, and DNA ladders became more apparent with increasing duration of ischemia.TUNEL positive cells with apoptotic morphologic characters were present in above ischemia time, and apoptotic index increased with increasing ischemia time.The majority of TUNEL positive cells were myocytes.Apoptotic index was higher in subendocardium than in subepicardium(P<0.101), while higher in border ischemia region than in the central ischemia area(P<0.105).CONCLUSION:A time-effect relation existed between the number of apoptosis and the time range of supposed time;Apoptotic myocytes scattered inthe ischemic myocardium, mainly localized at subendocardium and ischemic border.  相似文献   
99.
用分子生物学的方法合成了leptin长形受体(Ob-Rb)反意和正意核酸探针,用原位杂交法研究了5头2-3月龄母猪端脑一些结构内Ob-Rb mRNA的分布定位。结果表明,猪Ob-Rb mRNA分布于大脑皮质、梨状叶、海马、齿状回和杏仁核。大脑皮质和梨状叶内的Ob-Rb mRNA标记神经元主要位于第Ⅱ-Ⅵ层,分子层偶见标记神经元。海马结构内的Ob-Rm mRNA标记神经元主要位于海马的锥体细胞层和齿状回的颗粒层,在海马的始层和齿状回的多形层偶见标记神经元,在海马的辐射层和腔隙层罕见标记细胞。实验结果弥补了猪端脑内Ob-Rb mRNA分布定位资料的空白,为理解leptin的生理功能提供了形态学基础。  相似文献   
100.
以多头带绦虫Tm7重组蛋白为抗原,建立动物多头蚴病早期诊断方法.本研究从羊脑多头蚴原头节提取总RNA,采用RT-PCR技术首次扩增出Tm7基因的全序列,该基因的开放阅读框为207 bp,编码68个氨基酸.将此基因克隆到pET-32a(+)载体,构建重组表达质粒pET-32a-Tm7,经转化大肠杆菌BL21(DE3)后IPTG诱导表达,用SDS-PAGE和Western blot检测表达产物.以纯化后的表达蛋白作为抗原,建立检测羊脑多头蚴病抗体的重组蛋白间接ELISA方法.研究结果表明,Tm7基因在大肠杆菌中成功表达,表达产物为约27 ku的融合表达蛋白,该蛋白能识别羊脑多头蚴病阳性血清.建立的间接ELISA方法,检测敏感性可达93.3%,特异性达94.1%,研究结果表明Tm7重组蛋白可作为脑多头蚴病的诊断抗原.  相似文献   
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