籼稻与粳稻品种间叶绿体DNA的RFLP差异

用ＥｃｏＲＩ与ＡｖａＩ对栽培稻的７个籼稻品种和４个粳稻品种进行叶绿体ＤＮＡ（ｃｐＤＮＡ）的ＲＦＬＰ分析，结果显示籼稻品种的ｃｐＤＮＡ具有较高的多态性，粳稻品种的则较为均一．另外，栽培稻的ｃｐＤＮＡ并无严格的亚种特异性．     

四(1,4-二硫杂环己烯)四氮卟啉铜(Ⅱ)的氨敏特性

本文用四（1，4－二硫杂环己烯）四氨卟啉铜（Ⅱ）试制成厚膜电阻气敏元件，研究了元件的气敏特性．结果表明元件对一定浓度的氨气具有良好的敏感性和选择性．其灵敏度受工作温度、工作电压及元件制作工艺的影响．     

AFLP分子标记在鹀属遗传多样性分析中的初探

利用扩增片断长度多态性（AFLP）技术分析了鹀属(Emberiza)4种鹀(三道眉草鹀Emberi za cioides, 白头鹀Emberiza leucocephala, 白眉鹀Emberiza tristrami, 灰头鹀Emberiza spodocephala)基因组DNA的多态性. 在选取的39对引物中, 有11对能得到重复性好的多态性扩增条带， 每对引物扩增带数为27~76. 共得到535个标记位点, 其中429个为多态位点, 多态位点 比率达801%; 在UPGMA聚类关系图中， 4种鹀聚成一大类， 三道眉草鹀与白头鹀、 白眉鹀与灰头鹀分别两两相聚. 结果表明， AFLP可用于分析鹀属遗传多样性.     

一种适合抗癌药紫杉醇产生菌AFLP分析的DNA提取方法

比较研究了2种常规的DNA提取方法及一种新改进的抗癌药紫杉醇产生菌DNA提取方法.结果表明,CTAB提取法DNA产量低,多糖和蛋白质含量高;高盐低pH法(SD S法)提取DNA的产量较高,蛋白质和多糖含量高,需要进一步去除;新改进的DNA提取方法,DNA产量极高,而且蛋白质含量和多糖含量也低,适合AFLP分子标记技术对该菌的分子生物学研究.     

小麦-黑麦杂种体细胞无性系高配对突变体的细胞学和AFLP分析

以小麦-黑麦未经组织培养直接结实杂种及幼胚无性系变异再生杂种为材料,观察再生杂种的花粉母细胞减数分裂中期Ι染色体配对情况,发现杂种幼胚无性系变异再生杂种中存在一些配对频率大幅度提高的突变体,表现在有多个二价体及三价体、四价体.利用原位杂交技术对未经组织培养直接结实杂种及高配对无性系杂种染色体的组成和结构分析,结果显示经过无性系变异提高了W-R、R-R间的联会,表明组织培养对小麦和黑麦染色体配对造成了一定影响;进而利用基因组AFLP技术研究亲本和两种类型的杂种DNA序列上的差异,结果表明各种类型的杂种F1代均发生了广泛的基因组改变,主要表现为小麦、黑麦两亲本片段的缺失,且高配对无性系杂种基因组的变异大于未经组织培养直接结实杂种.本研究为进一步探究高配对变异的分子机理并利用该变异进行染色体重组奠定了基础.     

简析量子定位技术及应用前景

传统的卫星导航定位系统技术,其定位精度由于受限于电磁波脉冲的能量与带宽存在着一定的极限.随着量子力学的发展,利用具有量子纠缠特性的激光脉冲来取代电磁脉冲信号,可以实现趋近于物理极限的高定位精度,这就是量子定位技术.概述了量子定位的基本原理和特点优势的基础上,浅析了其关键技术及未来广阔应用前景.     

Physical location ofHelminthosporium carbonum susceptibility gene hm1 by FISH of a RFLP marker umc119 in Maize

A fluorescencein situ hybridization (FISH) procedure was adopted to physically map a RFLP marker, umc119 near the centromere of the long arm of linkage group1 in maize. The hm1 gene (Helminthosporium carbonum susceptibility gene) was linked closely with the marker umc119. RFLP markers are very good landmarks for mapping genes. Therefore, we also determined the position of the gene hm1 on the chromosome based on the physical location of umc119. The disease induced by infection ofHelminthosporium carbonum is one of the serious maize diseases and it distributes in many countries including China. Hybridization sites were showed on 1 L (long arm of chromosome1) and 5 L. The percentage distance from centromere to the hybridization site was 22.86 on 1 L and 58.23 on 5 L the detection rate was about 12% for mitotic cells. In interphase nuclei five hybridized sites were detected. It demonstrated that umc119 was multiplicated sequences. FISH has more advantages overin situ hybridization (ISH) detected by DAB for increasing the detection ratio and contrast between chromosomes and hybridization signals. The ability to detect the hybridization signal of a small low copy DNA sequence is a very important key towards wide application of FISH for plant genome mapping. Supported by the National Natural Science Foundation and Doctorate Vesting Point Foundation of the Education Committee of China Li Lijia: born in 1967. Ph. D.