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1.
Removing sodium from standard ionic contrastmedia markedly increases the incidence of ventricu-lar fibrillation in patients undergoing coronary arvgiography. Newer nonionic contrast media, Iopa-midol (IOP), Iohexol (IOH) and Ioversol (IOV),contain only trace amounts of sodium. To determinewhether sodium influences the fibrillatory propen-sity of nonionic contrast media, we measured theprolongation in QT interval and performed program-med electrical stimulation with l,2 and 3 ventricularextra stimuli in 40 dogs during 4 ml intracoronaryinjections of IOP, IOH and IOV. Solutions of eachcontrast media with added NaCI at concentrations of0.225To, 0.45% and 0.970 were compared to stockcontrast media. The addition of NaCI markedlyincreased the amount of QT interval prolongationproduced by each contrast media. With IOP, theamount of QT interval prolongation was 40+11msec with standard IOP but was 58+11 msec with0.225'70 NaCI/IOP, 84+17 msec with 0.45'To NaCI/IOP, and 132+42 msec with 0.970 NaCl/IOP(P相似文献
2.
六味地黄汤对实验性糖尿病大鼠心、肝、肾组织中过氧化氢酶活性和过氧化脂质含量的影响 总被引:7,自引:0,他引:7
用四氧嘧啶诱导雄性Wistar大鼠为模型进行研究.结果发现,四氧嘧啶大鼠血糖明显升高,且心、肝、肾组织中过氧化氢酶活性较正常组明显降低,过氧化脂质含量在心、肝组织中明显增高,过氧化脂质与过氧化氢酶比值在心、肝、肾组织中均明显高于正常组,表明糖尿病状态下大鼠心、肝、肾组织中均自由基生成增多,氧化损伤加重.经六味地黄汤治疗后,血糖明显下降,但心、肝、肾组织中的过氧化氢酶活性无改变;而心肌中过氧化脂质含量和过氧化脂质与过氧化氢酶比值则明显降低,过氧化脂质含量和过氧化脂质与过氧化氢酶比值在肝、肾组织中无变化,表明六味地黄汤能明显清除心肌中自由基,抑制心肌中脂质过氧化,且此作用并不是通过提高过氧化氢酶活性来达到. 相似文献
3.
用二甲苯所致的急性炎症模型观察了神效止痛膏的抗急性炎症作用.用扭体法、热板法观察了神效止痛膏对小鼠的镇痛作用.结果表明,神效止痛膏有很好的镇痛作用. 相似文献
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取32只2~3个月的BALB/C小白鼠,随机分为4组,每组8只,第1组为对照组,其余3个组为实验组,实验组小白鼠左腿皮下注射苯0.3ml(15ml/kg体重).注射后分别于24h,48h,72h脱颈处死。观察中毒前、后末梢血象、骨髓细胞、骨髓细胞构成的变化。结果表明,苯中毒时骨髓变化先于末梢血象的变化,骨髓的病变为造血细胞变性、坏死,大量毛细血管扩张、充血,骨髓细胞构成降低,而且骨髓细胞构成中细胞成分降低早于外周血粒细胞减少。 相似文献
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OBJECTIVE: To investigate the ultrastructure of rat thymus tissues with rat coronavirus (RCV) infection for clarifying the mechanism responsible for the morphological changes of the cells infected by RCV. METHODS: Routine electron microscopy was performed for observing RCV-infected rat thymus tissues. RESULTS: Following RCV infection, endoplasmic reticulum (ER) pools of different dimensions were observed in the cytoplasm of the thymic epithelial reticular cells, merging subsequently with each other into larger ER lakes filled with particles of mature RCV, or viral inclusion bodies. After germination on the ER membrane, the viruses entered the matrix of the ER lake to mature and were eventually excreted to the extracellular space. The RCV particles were spherical in shape with a diameter of 100-130 nm and two distinct membranes, the outer one being the envelope and the inner one the nuclear capsid to enclose the viroplasm. Between the envelop and nuclear capsid was a electron-lucent middle layer comprising one to two thin membranous structures. Large quantity of short spike-like projections starting from the nucleus capsid penetrated the middle layer and the envelop to reach the glycoprotein coat and formed a corona-like structure. Mature RCV particles were distributed around the ER pools, cytoplasm, and intercellular space, and the RCVs in the endosome/lysosome were devoid of the envelop and nuclear capsid. CONCLUSION: The ER lakes are involved in the maturation of the viruses, and the envelop and nuclear capsid of the virus entering the cells from extracellular space are removed and degraded in the endosome/lysosome. Replications of virus occurs in plasma of the thymic epithelial reticular cells, and no RCV can be detected in the thymocytes. 相似文献
10.
Implantation of bone marrow mononuclear cells using injectable fibrin matrix enhances neovascularization in infarcted myocardium 总被引:11,自引:0,他引:11
Ryu JH Kim IK Cho SW Cho MC Hwang KK Piao H Piao S Lim SH Hong YS Choi CY Yoo KJ Kim BS 《Biomaterials》2005,26(3):319-326
Neovascularization may improve cardiac function and prevent further scar tissue formation in infarcted myocardium. A number of studies have demonstrated that bone marrow-derived cells have the potential to induce neovascularization in ischemic tissues. In this study, we hypothesized that implantation of bone marrow mononuclear cells (BMMNCs) using injectable fibrin matrix further enhances neovascularization in infarcted myocardium compared to BMMNC implantation without matrix. To test this hypothesis, infarction was induced in rat myocardium by cryoinjury. Three weeks later, rat BMMNCs were mixed with fibrin matrix and injected into the infarcted myocardium. Injection of either BMMNCs or medium alone into infarcted myocardium served as controls. Eight weeks after the treatments, histological analyses indicated that implantation of BMMNCs using fibrin matrix resulted in more extensive tissue regeneration in the infarcted myocardium compared to BMMNC implantation without matrix. Examination with fluorescence microscopy revealed that cells labeled with a fluorescent dye prior to implantation survived in the infarcted myocardium at 8 weeks of implantation. Importantly, implantation of BMMNCs using fibrin matrix resulted in much more extensive neovascularization in infarcted myocardium than BMMNC implantation without matrix. The microvessel density in infarcted myocardium was significantly higher (p < 0.05) when BMMNCs were implanted using fibrin matrix (350 +/- 22 microvessels/mm2) compared to BMMNC implantation without matrix (262 +/- 13 microvessels/mm2) and medium injection (76 +/- 9 microvessels/mm2). In addition, average internal diameter of microvessels was significantly larger (p < 0.05) in BMMNC implantation with fibrin matrix group (14.6 +/- 1.2 microm) than BMMNC implantation without matrix group (10.2 +/- 0.7 microm) and medium injection group (7.3 +/- 0.5 microm). These results suggest that fibrin matrix could serve as a cell implantation matrix that enhances neovascularization efficacy for myocardial infarction treatment. 相似文献