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To study the gene expression profiles between immunologically injured liver cell and normal liver cell of mice and to screen
on a large scale the differentially expressed genes associated with the formation of liver injury, the experimental mice were
randomly divided into the normal group for controlling and the immunologically liver-injured group induced by BCG and LPS.
The liver mRNA of the two groups were extracted respectively and reversely-transcribed to cDNA with the incorporation of different
fluorescence (Cy3, Cy5) labeled dUTP as the hybridization probes. The mixed probes were hybridized to the cDNA microarray
chips. The fluorescent signal results were acquired by scanner ScanArray 4000 and analyzed with software GenePix Pro 3.0.
Among the 14112 target genes, 293 genes were found to be significantly differentially expressed, in which 188 genes were up-regulated
and 105 genes were down-regulated. Based on the analysis of biological functions of those differentially expressed genes,
it was indicated that the occurrence and development of mouse liver damage induced by BCG and LPS were highly correlated with
the processes of immune reactions, cell synthesis, metabolism, apoptosis and transportation in liver cell, which might be
quite important for elucidating the regulatory network of gene expression associated with the liver damage, also important
for finally discovering the pathogenic mechanisms of immunological liver damage. 相似文献
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Although superhydrophobic materials have attracted much research interest in anti-icing,some controversy still exists.In this research,we report a cost-effective method used to verify the contribution of area fraction to ice adhesion strength.We tried to partially-embed siliea nanopnarticles into microscale fabrics of a commercial polyamide mesh.Then,the area fraction could be determined by altering the mesh size.Generally,the ice adhesion strength decreases as the area fraction decreases.An ice adhesion strength of~1.9 kPa and a delayed freezing time of~1048 s can be obtained.We attribute the low ice adhesion strength to the combination of superhydro-phobicity and stress concentration.The superhydrophobicity prohibits the water from penetrating into the voids of the meshes,and the small actual contact area leads to stress concentration which promotes interfacial crack propagation.Moreover,our superhydrophobic mesh simultaneously exhibis a micro-nano hierarchical structure and a partally-cmbedded structure.Therefore,the as-prepared superhydrophobic mesh retained the ieephobicity after 20 icingldeicing cycles,and maintained its superhydrophobicity even afier 60 sandpaper-abrasion cycles and a 220"C thermal treatment. 相似文献
5.
目的:分析老年冠心痛患者服用抗血小板药物的依从性,寻求护理干预的有效途径.方法:自行设计服用抗血小板药物依从性调查表,通过调查与健康教育相结合的方式,对128例年龄在68~95岁的老年冠心病患者服药依从性问题进行调查分析.结果:通过临床医师知道抗血小板药物作用的占100%;知道终身服用抗血小板药物意义的占35%;服用抗血小板药物遇到问题而自行停药的占0%;健康教育后能坚持终身服用抗血小板药物的占95%.结论:相对于老年冠心痛患者,有效的健康教育能极大地提高患者服药依从性.临床医护人员对患者进行健康教育的同时,对家属的教育也很重要.通过健康教育干预,使其掌握药物的基本知识,告知获益大于风险,启动家庭支持系统,可显著提高老年冠心病患者服用抗血小板药物依从性. 相似文献
6.
Kinetic analysis of the zinc-dependent deacetylase in the lipid A biosynthetic pathway 总被引:1,自引:0,他引:1
The first committed step of lipid A biosynthesis in Gram-negative bacteria is catalyzed by the zinc-dependent hydrolase LpxC that removes an acetate from the nitrogen at the 2' '-position of UDP-3-O-acyl-N-acetylglucosamine. Recent structural characterization by both NMR and X-ray crystallography provides many important details about the active site environment of LpxC from Aquifex aeolicus, a heat-stable orthologue that displays 32% sequence identity to LpxC from Escherichia coli. The detailed reaction mechanism and specific roles of active site residues for LpxC from A. aeolicus are further analyzed here. The pH dependencies of k(cat)/K(M) and k(cat) for the deacetylation of the substrate UDP-3-O-[(R)-3-hydroxymyristoyl]-GlcNAc are both bell-shaped. The ascending acidic limb (pK(1)) was fitted to 6.1 +/- 0.2 for k(cat) and 5.7 +/- 0.2 for k(cat)/K(M). The descending basic limb (pK(2)) was fitted to 8.0 +/- 0.2 for k(cat) and 8.4 +/- 0.2 for k(cat)/K(M). The pH dependence of the E73A mutant exhibits loss of the acidic limb, and the mutant retains only 0.15% activity versus the wild type. The pH dependencies of the other active site mutants H253A, K227A, H253A/K227A, and D234N remain bell-shaped, although their significantly lower activities (0.25%, 0.05%, 0.007%, and 0.57%, respectively) suggest that they contribute significantly to catalysis. Our cumulative data support a mechanism for LpxC wherein Glu73 serves as the general base for deprotonation and activation of the zinc-bound water. 相似文献
7.
研究2010至2011年我院鲍曼不动杆菌的分布特征及耐药性变化,为临床合理应用抗菌药物提供依据.取自2010至2011年我院各科室送检的全部标本(包括血、尿、便、痰、分泌物等),经培养后,挑取纯菌落,进行菌种鉴定及药物敏感性分析.2010至2011年我院鲍曼不动杆菌的检出率不断上升,由2010年的4.6%上升到2011年的6.8%,以ICU病房鲍曼不动杆菌的上升最快.多重耐药鲍曼不动杆菌的检出率也不断增加,从2010年的1.7%上升到2011年的2.8%.鲍曼不动杆菌对多粘菌素B的耐药率为0%;多重耐药鲍曼不动杆菌对多粘菌素B的耐药率2 a分别为0%和7.8%.鲍曼不动杆菌及多重耐药鲍曼不动杆菌的检出率越来越高,鲍曼不动杆菌的耐药率也越来越高,多粘菌素B联合β-内酰胺类抗生素是目前针对鲍曼不动杆菌的最佳药物.临床应重视鲍曼不动杆菌及多重耐药鲍曼不动杆菌的感染,合理应用抗茵药物,以避免多重耐药鲍曼不动杆菌的流行. 相似文献
8.
Zα是能够特异性识别并结合左旋DNA(Z-DNA)的蛋白结构域,首先在人ADAR1中鉴定,随后又在ZBP-1(DLM-1)和E3L等蛋白质中发现了该结构域.鲫鱼PKZ是首次报道的具有Zα结构域的鱼类eIF2α激酶.为深入了解鲫鱼PKZ Zα的功能,原核表达并亲和层析纯化了3种多肽,即野生型PZα(Zα1Zα2)、替换型P(Zα1)2(Zα1Zα1)和点突变型(PZαK34A、PZαS35A、PZαR39A、PZαP57A).同时,构建了含有d(GC)6、d(GC)13、d(TA)13特殊插入序列的3种重组质粒,用于体外模拟Z-DNA.凝胶阻滞实验分析了3种多肽分别与重组质粒的亲和性结果表明,PZα和P(Zα1)2能够与d(GC)重组质粒结合,并且随着多肽含量的增加,阻滞效应越明显.与野生型PZα相比,替换型P(Zα1)2结合d(GC)重组质粒的能力更强PZα和P(Zα1)2还能微弱地与d(TA)13重组质粒结合.点突变型多肽都不能与重组质粒结合,暗示鲫鱼PKZ Zα结构域中这4个氨基酸残基在结合核酸分子的过程中非常关键.该文结果有利于进一步揭示鱼类PKZ Zα结构域与Z-DNA结合的分子机理. 相似文献
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10.
从基因水平探讨蛋氨酸脑啡肽对小鼠CD4'T细胞mRNA转录的影响。6~8周龄BALB/c雌性小鼠体内、外不同浓度MEK刺激。采用RT-PCR技术检测mRNA,所得不同浓度MEK刺激的CD4+T细胞mRNA和β-actin条带密度比值作为相对表达强度,所得数据采用SPSS11.5软件进行统计分析。4mg/mLMEK体内刺激及10-9~10-12mol/mL的MEK体外刺激促进小鼠CD4'T细胞mRNA转录;10-1~10-8mol/mL的MEK抑制小鼠CD4+T细胞mRNA的转录。10-13~10-14mol/mL的MEK对小鼠CD4'T细胞mRNA的转录无明显变化。适量浓度的MEK体内、外刺激能促进小鼠CD4+T细胞mRNA转录的高效表达。 相似文献