动物细胞工程中的诱变转化和选择系统

诱变转化和选择，是细胞工程产业化的重要环节，本文论述了诱变转化及选择的方法学及选择处理，介绍了抗药性选择法，营养缺陷型选择法，ＰＮＳ法，ＰＣＲ法和标记特异位点表达法等选择方法及其选择系统并对它们的优势与不足进行了比较。     

陶渊明研究中的选择性心理探析

选择性心理是人们面对纷繁复杂信息时普遍的心理现象。在文学研究中,这种现象大量存在,使人看到学术他律的因素有时是很惊人的。本文运用传播学的相关理论,分析论述选择性心理对陶渊明研究的影响,以期窥斑见豹。     

DNA methylation of fly genes and transposons

The use of anti-5-methylcytosine antibodies in affinity columns allowed the identification of methylated sequences in the genome of Drosophila melanogaster adults. In view of the presence of transposable elements amongst the identified sequences, it has been suggested that DNA methylation is involved in transposon control in the fly genome. On the contrary, a reanalysis of these data furnishes several intriguing elements that could raise new questions about the role that DNA methylation plays in the fly genome. The aim of the present paper is to discuss some features that emerge from the analysis of the identified methylated sequences. Received 26 January 2006; received after revision 8 May 2006; accepted 2 June 2006     

单片机80C51寻址方式的教学方法探讨

为了更好地教授汇编语言程序设计,需要掌握好各种不同的寻址方式。在教学中应突出重点,对于学生易混淆与忽视的地方应加强该部分内容的教学。     

基于多小波域对比度的图像融合算法

针对多小渡理论在图像处理领域的应用,给出了多小波域中图像的方向对比度的定义,并提出了基于多小波变换的、使用方向对比度进行自适应加权平均融合和选择性融合的算法.该算法利用多小渡变换对原图像进行分解,根据得到的分解系数计算相应的对比度,然后建立基于对比度的融合规则.使用这些算法对多谱图像进行了融合实验,并给出了评价融合质量的对比结果.结果表明,基于多小波变换的方向对比度的图像融舍算法在保留图像细节信息、增加信息量方面都有明显的提高.     

Genetic and environmental influences on reactive and spontaneous locomotor activities in rats

Paired groups of rats (derived from divergent, selective breeding or living in divergent environmental conditions) were compared with regard to locomotor activities. Intrapair differences were found to vary non-systematically, depending upon whether the rats were initially exposed to a test-environment with or without a slight environmental modification (reactive activities), or were allowed to habituate extensively to the environment (spontaneous activity). Since the behavioral patterns were found to represent distinct entities, this pointed to the necessity of differentiating clearly between spontaneous and reactive activities and indicated, once again, that both genetic and environmental influences are important in these behaviors and must be taken into account. Accepting and controlling for these variables makes it possible to use the factor of individual differences in laboratory animal behavior to advantage.     

Genetic and environmental influences on behavioral and neurochemical aspects of emotionality in rats

Summary Three pairings of rats (two derived from divergent, selective breeding and one from divergent environmental conditions) were compared with regard to behavioral and hormonal parameters. Striking differences were observed: results obtained in our own laboratory as well as those found in a review of the literature pointed to higher emotionality (e.g., increased defecation and corticosterone secretion, etc.) in Roman low-avoidance, Wistar-Kyoto and group-housed rats, as compared to their respective counterparts, Roman high-avoidance, spontaneously hypertensive, and individually housed Wistar rats. Concomitant receptor binding studies reviewed here (³H-diazepam- and³H-imipramine-binding sites) have revelaed, however, less consistent intrapair differences.     

亚硒酸根离子选择电极的研制及应用

本文以4,6-二溴代苤硒脑为活性物质,邻苯二甲酸二丁酯为增塑剂,PVC为支持体研制了亚硒酸根离子选择性电极.电极对硒(Ⅳ)的响应范围为3.2×10~(-6)～1.0×10~(-1)mol硒(Ⅳ)/L,斜率为-23.6mV(21℃),检测限为1.0×10~(-6)mol硒(Ⅳ)/L.     

含钒SBA-15介孔分子筛的制备及丙烷选择氧化反应

采用“pH-调节法”共合成得到不同钒含量的V-SBA-15催化剂,通过X射线粉末衍射、N2吸附、透射电镜、拉曼光谱、51V魔角旋转核磁共振谱、NHs-程序升温脱附、Hz-程序升温还原等手段对催化剂进行表征,并研究了其丙烷选择氧化反应的催化活性．结果表明,V-SBA-15催化剂保持SBA-15介孔分子筛的两维六方孔道结构,低含量时钒以高分散的孤立态四面体形式存在于分子筛的骨架中,高含量时出现聚集态的氧钒八面体物种．低钒含量的催化剂具有低酸量的弱酸性位和较低温度下的还原性,在丙烷选择氧化脱氢反应中表现出较高的催化活性．     

柴油机尾气选择性催化还原脱硝用蜂窝型催化剂的制备及其发动机台架测试性能

从催化剂粉末配方筛选、涂覆浆液配方及工艺优化等方面,讨论了蜂窝型整体催化剂制备过程的关键影响因素及其性能指标．对所制得的催化剂原粉、整体催化剂切块样品和整体催化剂分别进行了物理化学性能表征、催化性能微反测试以及发动机台架测试．台架测试结果表明,新型蜂窝型整体催化剂的选择性脱除氮氧化物的性能优异,即使使用高硫含量的市售国Ⅲ燃油,经过处理的尾气排放也远远超过国Ⅳ标准,达到国V标准,表明了该催化剂已具备实际推广应用的价值．