Evidence for existence of a close association between CD14 and CXCR4 on monocytic cell line U937

The surface expression of HIV-1 coreceptors (CXCR4 and CCR5) on monocytes can be regulated by the ligand of CD14, and the susceptibility of the cells to HIV-1 is then changed. Our previous study found that monoclonal antibody against CD14 could dramatically inhibit CXCR4-mediated chemotaxis and cell-cell fusion. Based on these studies, we explored potential relationship between CD14 and CXCR4 on monocytic cell line U937. Flow cytometry analysis showed that anti-CXCR4 monoclonal antibody (mAb) 12G5 strongly inhibited binding of the FITC-conjugated anti-CD14 monoclonal antibodies (TUK4 and UCHM1) to U937, while another CXCR4-specific mAb B-R24 did not show any effect on this binding. On the other hand, two anti-CD14 monoclonal antibodies (TUK4 and UCH-M1) obviously inhibited the binding of the PE-conjugated anti-CXCR4 mAb 12G5 to U937 but did not inhibit the binding of mAb 12G5 to CXCR4-transfected 3T3 cells (3T3.T4.CXCR4), which indicates that the blocking of mAb 12G5 binding to CXCR4 by CD14-specific mAbs is not involved in the possibility that CD14-specific mAbs directly bind to CXCR4. These results suggested existence of a close association between CD14 and CXCR4 on monocytic cell line U937.     

Stability analysis of BAM neural networks with time-varying delays

Some new criteria for the global asymptotic stability of the equilibrium point for the bi-directional associative memory neural networks with time varying delays are presented. The obtained results present the structure of linear matrix inequality which can be solved efficiently. The comparison with some previously reported results in the literature demonstrates that the results in this paper provide one more set of criteria for determining the stability of the bi-directional associative memory neural networks with delays.     

基于关系矩阵的复合宽边界区域拓扑关系计算

简单宽边界区域拓扑关系计算比较简单,而复合宽边界区域拓扑关系计算比较复杂,因而需要一个计算方法以实现复合宽边界区域拓扑关系计算、查询和分析处理。在分析复合宽边界区域与简单宽边界区域关系联系的基础上,研究了根据复合宽边界区域中简单宽边界区域拓扑关系矩阵计算复合宽边界区域拓扑关系的方法,并根据复合宽边界区域的性质,简化了算法。计算方法使得扩展九交模型不再是一个概念模型,而是可计算的,从而为查询和分析处理宽边界区域拓扑关系奠定了基础。     

活性炭对4—氨基安替比林提纯作用的评定——针对水质监测中对挥发酚的监测分析

在挥发酚的监测分析中,本文通过应用苯与活性炭分别对显示剂4-氨基安替比林(C11H13N3O)做去渣、脱色对比实验,阐明了活性炭对4-氨基安替比林(C11H13N3O)显示剂的去渣、脱色作用无论是在分析的操作上,还是对人体的毒性、分析成本和再生性上都比用苯(C6H6)对其进行处理具有优越性。并通过近三年的实验,验证了其精确性和准确性,说明利用活性炭替代苯对显色剂进行预处理,能够符合我国《水和废水监测分析方法》和《环境水质监测质量保证手册》的相关要求。     

关于大学英语分级教学模式的思考

大学英语分级教学模式是各高校英语教学改革的趋势。文章首先分析了分级教学的理论依据，着重分析了分级教学利弊．最后指出了分级教学应注意的问题，并提出了相应的对策。     

Synthesis, Characterization and Calorimetry of Ni（C4H8N2O3）2Cl2

A coordination complex was synthesized from NiCl2 and dipeptide glycylglycine（GG）. It was characterized by element analysis, NMR and TG methods, and then was determined to be Ni（C4HsN2O3）2Cl2. Using an isoperibolic reaction calorimeter, the standard molar enthalpy of formation of Ni（GG）2Cl2（solid） has been determined to be -（1 674.66±2.02） kJ · mol^-1 at 298.15 K.     

加碳方式对磷酸铁锂动力学及电化学性能的影响

以FeSO4.7H2O和NH4H2PO4为原料,以H2O2为氧化剂,通过液相沉淀法制得前驱体FePO4,然后通过碳热还原反应制得LiFePO4。采用2种加碳方式:方法一是先制得FePO4,然后加入乙炔黑混合后高温合成LiFePO4;方法二是先把乙炔黑分散在液相中,然后通过液相沉淀制得含碳的FePO4,再高温合成LiFePO4。研究结果表明:采用方法二合成的LiFePO4动力学及电化学性能比方法一合成的优。采用方法二所制备的LiFePO4样品以0.1C的倍率放电,其比容量达149 mA.h/g;当放电倍率为1C时,其比容量为124 mA.h/g,且循环性能良好。     

Eph受体家族和Ephrin-A5在NSCLCs中上调表达及其临床意义(英)

采用荧光实时定量PCR的方法在48个非小细胞肺癌组织以及配对的正常肺组织中检测Eph/ephrin 基因的mRNA水平.发现肺癌组织中EphB4, EphB3 和 ephrin-A5的表达水平与配对的正常肺组织相比分别上调了60%，81%和65%,并具有显著的统计学差异. 而且，统计学分析发现ephrin-A5的表达水平与肿瘤分型、转移、性别、吸烟以及诊断年龄等临床病理学参数之间存在显著的相关性.此外，EphA2的表达水平与肿瘤大小、家族遗传史以及诊断年龄之间也存在显著的相关性.总之，这些结果提示EphB4, EphA2, EphB3 和ephrin-A5 在肺癌的发生和发展过程中可能以一种单独或者协同的形式发挥作用.这些蛋白有可能成为研究和诊断肺癌的重要靶向基因.     

基于最小二乘法的自适应电流速断保护中系统参数的实时计算

对自适应电流速断保护中实时计算系统参数的算法进行了研究.提出了在系统发生故障时采用带补偿的全波傅氏算法,基于最小二乘法推导全波傅氏算法的补偿分量,并实时计算出系统的等值内电抗,然后再利用记忆在计算机存储器中的故障前的测量电压、电流采样值来计算系统等值内电势的相电势幅值Em.     

活性炭对2，4-二氯苯酚的催化臭氧化降解

研究了粒状活性炭（GAC）对2，4-二氯苯酚（2，4-DCP）臭氧化降解的催化性能。由于活性炭的吸附和催化作用，提高了2，4-DCP的分解。在酸性条件下具有较高的催化臭氧化效率，而酸性和碱性的强弱对2，4-DCP的分解几乎没有影响。活性炭的重复使用实验表明活性炭在臭氧化处理过程中可以得到原位再生，多次使用后其催化活性几乎没有降低。