β淀粉样肽1～42单克隆抗体的制备

目的　制备稳定分泌β -淀粉样肽 1～ 4 2 (Aβ1-42 )单克隆抗体的杂交瘤细胞 ,产生高效价抗体。方法　通过基因工程技术 ,将Aβ1-42 基因融合于乙肝核心抗原 (HBcAg)的主要免疫优势区 (MIR) ,制备Aβ和HBcAg的融合蛋白 ,免疫BALB/c小鼠 ,取脾细胞与SP2 / 0细胞融合 ,筛选能稳定分泌Aβ1-42 单克隆抗体的杂交瘤细胞。结果　得到两株能稳定分泌Aβ1-42 单克隆抗体的杂交瘤细胞 ,Aβ1-42 单克隆抗体的Ig亚类为IgG3 。结论　制备得到的Aβ1-42 单克隆抗体特异性强 ,效价高     

DESIGN OF A DIGITAL SIGNATURE SCHEME BASED ON FACTORING AND DISCRETE LOGARITHMS

Objective Focusing on the security problem of authentication and confidentiality in the context of computer networks, a digital signature scheme was proposed based on the public key cryptosystem. Methods Firstly,the course of digital signature based on the public key cryptosystem was given. Then, RSA and ELGamal schemes were described respectively. They were the basis of the proposed scheme. Generalized ELGamal type signature schemes were listed. After comparing with each other, one scheme, whose Signature equation was (m r)x=j s modФ(p) , was adopted in the designing. Results Based on two well-known cryptographic assumptions, the factorization and the discrete logarithms, a digital signature scheme was presented. It must be required that s“ was not equal to p‘q“ in the signing procedure, because attackers could forge the signatures with high probabilities if the discrete logarithms modulo a large prime were solvable. The variable public key “e“ is used instead of the invariable parameter “3“ in Ham‘s signature scheme to enhance the security. One generalized ELGamal type scheme made the proposed scheme escape one multiplicative inverse operation in the signing procedure and one modular exponentiation in the verification procedure.Conclusion The presented scheme obtains the security that Harn‘s scheme was originally claimed. It is secure if the factorization and the discrete logarithms are simultaneously unsolvable.     

THE GENE EXPRESSION OF BDNF IN NORMAL RABBIT RETINA

Objective To investigate the distribution of brain-derived neurotrophic factor(BDNF) protein in the rabbit retina. Methods Immune response material in the retina was observed using BDNF antibody by the method of immunohistochemistry. Results BDNF gene expression was mainly found in the RGCs, also in innernuclei cells and outernuclei cells in rabbit retina. Conclusion RGC is not only the target cell of BDNF, but also express the BDNF protein. BDNF from multi-sources participates in the regulation of RGCs.     

郑西高铁客流特征及市场营销策略研究

对郑西高铁客流社会经济特性、旅客出行特征、旅客出行意愿特征进行分析,并进行了客流市场的细分,分析得出郑西高铁客流市场定位应主要服务于中高端客流,目标市场主要为因公出差、探亲访友、经商、旅游等公务、商务客流,即综合价值型客流子群体及效率型客流子群体,在市场营销方面提出提升服务,形成品牌,建立现代化营销体制,整合运输资源,延伸产品链,优化票制的市场营销策略。     

电控陀螺罗经改进

结合某型电控陀螺罗经在长期使用过程中存在的问题.详细介绍了该型电控陀螺罗经的改进方案,主要包括电源子系统、主罗经子系统、微机控制子系统三个部分.此项改造任务对于提高经济性和老设备的更新换代有积极的借鉴意义.     

矢量变频调速系统仿真研究

建立了三相异步电动机在旋转坐标系下的数学模型,论述了空间矢量脉宽调制技术原理.利用 Matlab软件对电压源型 SVPWM 交流调速系统进行了仿真,给出了仿真结果,并进行了分析.     

四卷筒桥式抓斗卸船机抓斗开闭问题的研究

对四卷筒抓斗卸船机抓斗开闭的影响因素进行定量分析,根据悬索理论,给出了悬垂段钢丝绳的悬垂方程。     

舰船液舱容量机器人自动测量系统简介

简要介绍液舱容量计量的机器人自动测量系统,包括系统的的组成、机器人控制、图像采集与传输、无线局域网通信等有关技术以及系统的功能.     

基于STM32的蓄电池检测系统设计

蓄电池检测系统是蓄电池质量指标中非常重要的一环,直接影响蓄电池的性能和寿命。本文介绍一种以STM32微处理器STM32F103RCT6为核心的铅酸蓄电池高精度智能检测系统,可以同时检测电压、温度、液位,并根据神经网络计算得到电解液密度,用户在上位机完成测试参数设置,自动对电池的各项数据进行存储和报警。文中详细介绍了系统组成、硬件和软件设计。实践证明该检测系统满足实际需求。     

基于动态链接库的海上溢油数据库设计与研究

船舶海上溢油事故给国家财产和海洋环境造成巨大损失,有效的事故处理措施能够大大降低事故后果,而紧急处置综合指挥系统作为岸上人员调度和指挥的核心,合理和完整的指挥系统数据库的设计显得极其重要。为了对海上溢油事故进行综合指挥,在分析综合指挥系统数据库构成及关联关系的基础上,阐述了数据库设计的准则以及存在的关键技术,对健全我国海上溢油规章制度有着重要意义。