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111.
目的 从观察鼠骨骼肌组织形态学改变和VEGF表达的角度研究CNTs/HAP纳微米复合材料对鼠骨骼肌的细胞毒性。方法 将CNTs/HAP纳米复合材料植入实验鼠臀大肌。按不同时间取材,做组织学观察和RT-PCR分析。结果 1d、3d显微镜下观察,炎细胞和淋巴细胞浸润伴轻度水肿、间质疏松;5d、7d显微镜下观察血管壁增厚,单核巨噬细胞和纤维组织增生,少量肌纤维出现变性,VEGF表达呈上升趋势;14天显微镜下观察周围组织间质血管扩张,仅有少量炎细胞浸润,水肿不明显,VEGF表达呈下降趋势。结论 CNTs/HAP对鼠骨骼肌细胞无毒性,有利于血管的再生,具有良好的生物相容性。 相似文献
112.
D-二聚体与纤维蛋白原在冠心病中的临床意义 总被引:7,自引:1,他引:7
目的 探讨D-二聚体(D-Dimer,DD)与纤维蛋白原(FS)的含量在冠心病及冠状动脉不同程度的病变患者中的差异。方法 将入选的130例经冠状动脉造影(CAG)的患者分为冠心病组94例与正常对照组36例,其中冠心病组又分为急性心肌梗死(AMI)组25例,不稳定型心绞痛(UAP)组36例。稳定型心绞痛(SAP)组33例。再将冠心病组按CAG结果分为轻度病变组24例,中度病变组27例,重度病变组43例。用免疫透射比浊法分别测定DD,FS含量。结果 AMI、UAP两组DD、FS含量及阳性检出率明显高于SAP和对照组(P〈0.05),AMI组的DD、FS含量明显高于UAP组(P〈0.05),重度病变组DD,FS含量高于轻、中度病变组(P〈0.05)。结论 联合检测DD与Fg在冠心病及判断冠状动脉病变程度中具有重要的临床意义。 相似文献
113.
Effect of ketamine on apoptosis by energy deprivation in astroglioma cells using flow cytometry system 总被引:3,自引:0,他引:3
Apoptosis is a programmed, physiologic mode of cell death that plays an important role in tissue homeostasis. As for the central nervous system, ischemic insults can induce pathophysiologic cascade of apoptosis in neurophils. Impairment of astrocyte functions during brain ischemia can critically influence neuron survival by neuronglia interactions. We aimed to elucidate the protective effect of ketamine on apoptosis by energy deprivation in astrocytes. Ischemic insults was induced with iodoacetate/ carbonylcyanide m-chlorophenylhydrazone (IAA/CCCP) 1.5 mM/20 microm or 150 microm/2 microm for 1 hr in the HTB-15 and CRL-1690 astrocytoma cells. Then these cells were reperfused with normal media or ketamine (0.1 mM) containing media for 1 hr or 24 hr. FITC-annexin-V staining and propidium iodide binding were determined by using flow cytometry. Cell size and granularity were measured by forward and side light scattering properties of flow cytometry system, respectively. An addition of ketamine during reperfusion increased the proportion of viable cells. Ketamine alleviated cell shrinkage and increased granularity during the early period, and ameliorated cell swelling during the late reperfusion period. Ketamine may have a valuable effect on amelioration of early and late apoptosis in the astrocytoma cells, even though the exact mechanism remains to be verified. 相似文献
114.
An anthrax lethal factor-neutralizing monoclonal antibody protects rats before and after challenge with anthrax toxin
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Lim NK Kim JH Oh MS Lee S Kim SY Kim KS Kang HJ Hong HJ Inn KS 《Infection and immunity》2005,73(10):6547-6551
Lethal factor (LF) is a component of anthrax lethal toxin (LeTx). We generated anti-LF murine monoclonal antibodies (MAbs) that show LeTx-neutralizing activity in vitro and in vivo. Anti-LF MAbs were generated by immunization with recombinant LF, and the MAbs showing LeTx-neutralizing activity in vitro were selected. Two MAbs with the highest affinities, 5B13B1 (dissociation constant [K(d)], 2.62 nM) and 3C16C3 (K(d), 8.18 nM), were shown to recognize the same or closely overlapping epitopes on domain III of LF. The 50% inhibitory concentration of 5B13B1 (0.21 microg/ml) was approximately one-third that of 3C16C3 (0.63 microg/ml) in the in vitro LeTx-neutralization assay. The 5B13B1 antibody, which had the highest neutralizing activity, provided perfect protection against LeTx challenge in an in vivo LeTx neutralization assay using Fisher 344 rats. In addition, the antibody showed pre- and postexposure prophylactic effects in the animal experiments. This is the first report that an MAb binding to domain III of LF has neutralizing activity against LeTx. The 5B13B1 antibody may be useful in prophylaxis against anthrax poisoning. 相似文献
115.
Bardag-Gorce F Wilson L Nan L Li J French BA Morgan TR Morgan K French SW 《Experimental and molecular pathology》2005,78(3):207-211
Mallory body (MB) formation is a complex phenomenon seen in chronic liver disease. CYP2E1 may play a role in preventing MB formation since it is involved in the elimination of toxic drugs and chemicals. When mice were fed with diethyl-1,4-dihydro-2,4,6-trimethyl-3,5-pyridinedicarboxylate (DDC) for 10 weeks, Mallory bodies (MBs) developed in the liver at the end of this period. When DDC feeding was combined with CMZ (an efficient in vivo CYP2E1 inhibitor), more MBs formed compared to DDC feeding alone. DDC was shown to be a suicide inhibitor of CYP2E1. The level of CYP2E1 protein in the liver was further reduced by the DDC and CMZ treatment when measured by Western blot. To test whether CYP2E1 reduced MB formation, CYP2E1 knockout mice and CYP2E1 overexpressed mice were fed with DDC or DDC and CMZ for 10 weeks. MB formation increased markedly in the liver of CYP2E1 knockout mice when fed with DDC only. CYP2E1 overexpressed mice showed an increase in MB formation when the mice were fed with the combination of DDC and CMZ where the amount of CYP2E1 was reduced to levels seen in wild type mice. It was concluded that CYP2E1 inhibits MB formation by increasing the rate of elimination of DDC and/or its toxic intermediates. 相似文献
116.
Study on the metastatic mechanisms of human giant-cell lung carcinoma comparison between the strains C and D 总被引:4,自引:0,他引:4
Mei L Lezhen C Po Z Zheng G Yali L Nan L 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》1998,16(4):167-176
The biologic characteristics of the two human giant-cell lung carcinoma strains with high (strain D) and low metastatic potential (strain C) were studied, including karyotype of chromosome, intracellular free calcium ([Ca2+]i), morphologic changes of cell surface and the expression of nm23-H1, p53, ras, c-myc, c-erbB2, bcl-2 genes and PCNA. The correlation between different biologic features and the metastatic potential of the two strains was analyzed. We found: 1) Both strains had the karyotypic abnormality of -13, -14, -15, +20, +21 with seven same marker chromosomes. Only strain D had the karyotypic abnormality of +7, -17, -18, +X, 7p+; 2) [Ca2+]i of the strain C (984.7 +/- 573.8) and D (517.6 +/- 216.6) was significantly different (p < 0.05). The amplitude of intracellular calcium oscillations of strain C was lower than the one of strain D; 3) strain C had more villous-like protrusions on the cell surface, whereas strain D had more bubble-like protrusions; 4) The expression of nm23-H1 and p53 protein of strain C was all higher than that of strain D. The expression of PCNA of strain C was lower than strain D; 5) nm23-H1 mRNA levels of strain C was lower than that of strain D. We consider that the karyotype of chromosomes, intracellular free calcium, the structure of cell membrane and the expression of nm23-H1 gene, p53 gene, PCNA could be closely related to the metastatic potential of human giant-cell lung carcinoma. They could be used as the sign for judging whether the tumor will metastasize in clinical practice as well as in judging the prognoses of patients. 相似文献
117.
目的探讨我国部分省份(地区)汉族人群HLA-I类经典基因座位HLA-A、HLA-B、HLA-Cw位点的群体遗传学特点及其基因频率分布的地区差异。方法选取1014例无关汉族拟行造血干细胞移植治疗患者及其健康家系供者的血液样本,提取基因组DNA后,采用序列特异性引物聚合酶链式反应(PCR-SSP)分型技术进行HLA-A、HLA-B、HLA-Cw位点基因分型,分析不同地区汉族人群及不同种族间的基因频率分布特征。基于文献报道的我国不同地区汉族人群及不同种族的HLA-I类基因频率资料,计算种群间遗传距离(D),比较不同地区汉族人群及不同种族间遗传距离差异。结果Hard-Weinberg吻合度检验表明,本研究抽样群体适于进行遗传学统计分析。HLA-A位点共检测出14种基因型,最常见的是A^*02(0.330)、A^*11(0.240)、A^*24(0.155)、A^*33(0.075);HLA-B位点共检测出27种基因型,最常见的是B^*13(0.134)、B^*15(0.143)、B^*40(0.133)、B^*46(0.102);HLA-Cw位点共检测出13种基因型,最常见的是Cw^*01(0.157)、Cw^*03(0.247)、Cw^*07(0.181)、Cw^*08(0.106)。群体汉族与其他人种间HLA-A、HLA-B基因频率差异均有统计学意义(P〈0.05);除兰州汉族人群仅同南方汉族、湖南、山东、江苏、台湾汉族人群间HLA-A、HLA-B基因频率差异有统计学意义(P〈0.05)外,其余各地区汉族人群间HLA-A、HLA-B基因频率差异均有统计学意义(P〈0.05)。各地区汉族人群间平均遗传距离D=0.164,辽宁和北方汉族人群间遗传距离(D=0.064)最小,江苏与湖南汉族人群间遗传距离(D=0.299)最大;不同地区汉族人群间遗传距离普遍小于种族间遗传距离。结论我国不同地区汉族人群HLA-I类基因频率分布存在显著差异,但其差异要明显小于世界不同人种间的分布差异。我国汉族人群所特有的HLA-I类基因频率分布格局资料对区域性疾? 相似文献
118.
Opening of the mitochondrial permeability transition pore has been recognized to be involved in cell death. The present study investigated the effect of beta-carbolines (harmaline and harmalol) on the MPP(+)-induced change in the mitochondrial membrane permeability and cell death in differentiated PC12 cells. beta-Carbolines and antioxidants (superoxide dismutase, catalase, ascorbate or rutin) prevented the loss of cell viability in PC12 cells treated with 250 microM MPP(+), while the effects of N-acetylcysteine and dithiothreitol were not observed. beta-Carbolines reduced the condensation and fragmentation of nuclei caused by MPP(+) in PC12 cells. beta-Carbolines alone did not exhibit a significant cytotoxic effect on PC12 cells. beta-Carbolines (50 microM) inhibited the decrease in mitochondrial transmembrane potential, cytochrome c release, activation of caspase-3, formation of reactive oxygen species (ROS) and depletion of GSH caused by MPP(+) in PC12 cells. beta-Carbolines reduced the hydrogen peroxide- or SIN-1-induced cell death in PC12 cells. The results suggest that beta-carbolines may attenuate the MPP(+)-induced viability loss in PC12 cells by inhibition of change in the mitochondrial membrane permeability and by antioxidant effect. 相似文献
119.
目的 了解某三甲专科医院血源性病原体职业暴露发生现况,为降低职业暴露风险采取有效防控措施提供参考。方法 利用某三甲专科医院2018—2020年发生的职业暴露相关数据进行回顾性研究,从职业暴露的工作类别、工龄、种类、病原体类别等方面开展统计分析,使用Fisher确切概率法进行组间比较。结果 2018—2020年,该院共发生血源性病原体职业暴露114例,其中锐器伤暴露94例,占比最高(82.5%);护士发生职业暴露64例,占比最高(56.1%);工龄≤1年人员发生职业暴露70例,占比最高(61.4%);职业暴露主要发生在处理丢弃针头等锐器物(35.9%)和检查、治疗及护理操作(22.8%)等环节。卡方检验结果显示,不同职业类别人员发生职业暴露的类型不同,医技人员和护士发生血液/体液暴露比例更高(x2=9.774,P<0.05)。对所有发生职业暴露的工作人员建立健康随访档案,定期追踪监测,尚未发现人员因职业暴露而感染血源性疾病。结论 通过对低年资医务人员和工勤人员职业防护的精准培训、强化标准预防和标准化操作规程、提供安全用具、完善血源性病原体职业暴露的监测和防护体系等综合性集束化措施,降低职业暴露风险,为采取有效防控提供依据。 相似文献
120.
目的:探讨血清脂联素(APN)、骨桥蛋白(OPN)和人附睾分泌蛋白4(HE4)在子宫内膜癌患者中的表达及意义。方法:选取2019年11月至2022年9月郴州市第一人民医院收治的子宫内膜癌患者62例(子宫内膜癌组),另选取同期50例子宫内膜不典型增生患者(内膜增生组)和50例健康志愿者(正常内膜组)。检测并比较三组血清APN、OPN、HE4水平,采用受试者工作特征(ROC)曲线分析血清APN、OPN、HE4对子宫内膜癌的诊断效能,并采用Spearman相关性分析探讨血清APN、OPN、HE4与临床病理特征的相关性。结果:子宫内膜癌组患者血清APN水平低于内膜增生组和正常内膜组,OPN、HE4水平高于内膜增生组和正常内膜组。国际妇产科联盟(FIGO)分期为Ⅲ期患者血清APN水平低于Ⅱ期和Ⅰ期患者,OPN、HE4水平高于Ⅱ期和Ⅰ期患者;肌层浸润深度≥1/2肌层患者血清APN水平低于<1/2肌层患者,OPN、HE4水平高于<1/2肌层患者;淋巴结转移患者血清APN水平低于无淋巴结转移患者,OPN、HE4水平高于无淋巴结转移患者,差异均具有统计学意义(P <0.05)。ROC曲... 相似文献