手性配合物[Mn（csal-R,R-chxn）]Cl的CD光谱和不对称催化作用

以5-氯-水杨醛双缩（1R,2R）-环己二胺（CSA-DMC）为原料制备了手性[Mn（csal-R,R-chxn）]Cl配合物,测定了手性配体CSA-DMC的荧光光谱,研究了手性配合物[Mn（csal-R,R-chxn）]Cl的CD光谱及催化苯乙烯不对称环氧化反应的催化性能.结果表明：手性配体CSA-DMC的荧光发射峰处于517 nm;利用激子裂分方法和d-d跃迁关联法推测了手性席夫碱配合物[Mn（csal-R,R-chxn）]Cl绝对构型为（R）Δλ构型;最适宜反应条件下,催化苯乙烯的不对称环氧化反应的转化率为74.9%,催化剂选择性为67.6%,对映体过量百分率（e.e.）为12.3%     

Efficacy of anti-CD20 chimeric Fab’ fragment on proliferation of B lymphoma cells

The variable domain of heavy chain (V_H) and light chain (V_L) genes of anti-CD20 monoclonal antibody HI⁴⁷ were cloned from anti-CD20 ScFv expression vector pCANBTEcd20 by PCR and ligated into vector pYZF to construct chimeric anti-CD20 Fab’ fragment expression vector pYZFcd20. Chimeric anti-CD20 Fab’ fragment was expressed inE. coli 16C9 and purified by protein G affinity chromatography. Competitive inhibition assay showed that anti-CD20 Fab’ fragment inhibited binding of HI⁴⁷ to CD20 on the surface of Daudi cells. Results from MTT assay indicated that chimeric anti-CD20 Fab’ fragment inhibited the proliferation of Daudi cells, IC₅₀ = 69 μg/mL. Affinity of chimeric anti-CD20 Fab’ fragment was determined, K_a was about 8.9×10⁸ (mol/L)⁻¹.     

Isolation, purification and characterization of secondary structure of antifreeze protein fromAmmopiptanthus mongolicus

Antifreeze protein (AFP) from Ammopiptanthus mongolicus leaves was isolated and purified with DEAE cellulose 52, Sephacryl 300, heat treatment and preparative isotachophoresis. The molecular weight of AFP was 50 ku by SDS-PAGE measurement. The average thermal hysteresis activity (THA) of AFP was 0.35℃ at 5 mg/mL using a differential scanning calorimeter (DSC). This AFP showed heated stability. From circular dichroism (CD) of AFP spectral data from 195—240 nm, a well-defined secondary structure of 11% a-helix, 34% antiparallel b-sheet and 55% random coil for the plant AFP was deduced.     

Construction and expression of retroviruses encoding dual drug resistance genes in human umbilical cord blood CD34+ cells

A series of retro viral vectors encoding humanmdr1 gene alone as wetl as in combination with either humanmgmt gene or human mutantSer ³¹-dhfr gene are engineered. The resultant retroviruses are used to transduce human umbilical cord blood CD34⁺ cetls. It has been shown that expression of dual drug resistance genes in transduced cetls confers a broad range of resistance to both kinds of corresponding drugs. These data suggest a rationale for the use of such double chemoresistance gene constructs in anin vivo model in which transduced hematopoietic cetls will acquire multiple protection against the cytotoxic side effects of combination chemotherapy and may have future application in chemoprotection of normal tissues, thus killing tumor cetls more effectivety.     

基于光盘质量的动态自适应技术的设计与实现

采用动态自适应技术来根据光盘质量对主轴转速作自适应的调整,以最佳的速度读取光盘数据,有利于数据的顺利读取和保护光头组件。相应地针对光盘反射信号的质量提出一种间接评估数据质量的方法,设计了基于光盘质量的动态自适应技术,并应用于高速光盘驱动器伺服控制系统中。     

手性四薄荷基亚甲基双膦酸酯的制备与性质表征

膦酸及其酯的衍生物是有机磷化合物中重要的一部分,已被广泛应用于医药、农药、表面活性剂、金属防腐剂、高分子材料、工业软水剂等化工领域.其所含有的P—C—P键和烷氧基有许多可能的结构变化,是个很好的合成子.用亚甲基双膦酰二氯和薄荷醇反应,合成了手性四薄荷基亚甲基双膦酸酯(L2),并对其进行了IR、EA、1HNMR、31P NMR和CD等性质表征.用该双膦酸酯合成了三种新的配合物,并进行了红外表征.     

网络课件、网络课程光盘数据库查询方法的实现

介绍了两种网络课件、网络课程等制作完成后生成光盘,脱离后台服务器支持,实现光盘数据库查询功能的解决方法：一是HTML网页内嵌JavaScript或VBScript脚本访问本地数据库(MS Access);二是采用HTML Appucadon(HTA)形式来访问数据库．     

关于艾滋病疗法评价及疗效预测的数学模型

艾滋病是当前人类社会最严重的瘟疫之一,从1981年至今,它已夺去了近3000万人的生命。通过美国艾滋病医疗试验机构ACTG公布的两组数据,建立了艾滋病疗法评价及疗效预测模型。总体上,对所给定的不同疗法做出优劣评价,运用最小二乘法原理结合所给数据中的CD4和HIV值,建立数据模型,对四种不同程度的病人继续治疗的效果做出预测并确定最佳治疗终止时间。在兼顾治疗费用的条件下,对不同的治疗方法给出较合理的评判。最后,对模型做出分析、评价和改进。     

Comparison of protein synthesis profiles in chronic lymphocytic leukaemia cells and B-lymphocytes from peripheral blood,cord blood and tonsil

2D-gel electrophoresis was used to investigate protein synthesis in leukaemic cells from a series of 15 chronic lymphocytic leukaemia (CLL) patients, and in non-malignant B-cell populations from different sources. The protein synthesis profiles of CD5+ B-cells from umbilical cord blood and from tonsil were determined, and the levels of expression of their proteins were observed to be similar to the CLL cells. The CD5-cells from cord blood resembled peripheral blood B-lymphocytes, and the protein synthesis profile of CD5-cells from tonsils was very complex. One protein was also identified which consistently appeared to be synthesised at a low level in CD5+ B-cells from tonsil but which was always more prominant in CLL cells and other non-malignant B-lymphocytes. On the basis of these data it is possible that the closest non-malignant counterpart to CLL is the CD5+ B-lymphocyte from cord blood.     

加强对随书光盘的科学管理 提高其利用率

本文通过实例引出目前图书馆随书光盘利用率低这一普遍存在问题 ,并提出图书馆随书光盘利用率低的根本原因是管理不善造成的 ,接着分析了当前一些图书馆的管理方法利弊并提出了作者自己设计的几种科学管理模式 ,同时呼吁质量监管部门应从用户的角度出发 ,加强对生产光盘的厂家的监管力度 ,保证光盘的质量