荜拔中的新酰胺成分

从荜拔地上部分乙醇提取物中分得５个化合物,经波谱分析确定其结构分别为：（α,β,α,β）－１,３－双（３,４－二甲基苯基）－２,４－双［１－（２－羰基－５,６－二氢吡啶）－甲酰基］－环丁烷（１）。     

懒猴属的核糖体DNA变异及其种间分化关系

用１５种限制性内切酶和人２８Ｓ、１８ＳｒＤＮＡ探针构建了懒猴属各物种核糖体ＤＮＡ重复单位的限制性内切酶图谱。在进化速率较高的非转录间隔区,在大、中、小懒猴中分别定位了２３、２４、２４个酶切位点。大懒猴与中懒猴有１２个位点不同,与小懒猴有１４个位点不同,而中、小懒猴间则只有一个位点的差异。经过计算,大懒猴与中懒猴的遗传距离值为１２．６５％,与小懒猴的差异为１４．２４％,中、小懒猴间的差异则仅为０．７     

云南姬鼠的蛋白多态性及其遗传分化关系

本文采用蛋白电泳技术对来源于云南省若干地区的姬鼠属（Ａｐｏｄｅｍｕｓ）的３种姬鼠──高山姬鼠（Ａ．ｃｈｅｖｒｉｅｒｉ）８只,中华姬鼠（Ａ．ｄｒａｃｏ）３只和大耳姬鼠（Ａ．ｌａｔｒｏｎｕｍ）１只,以及作为外群的同科的绒鼠属的大绒鼠（Ｈａｐａｌｏｍｙｓｄｅｌａｌｏｒｉ）３只进行了分析。共检测遗传座位２７个,发现２１个座位存在多态性。根据蛋白多态的数据对研究对象进行遗传分化关系的探讨,用系统分析软件ＰＨＹＬＩＰ计算它们之间的分化关系,得到了一棵无根系统树。结果表明,作为外群的大绒鼠明显不同于其它３种姬鼠而聚在最外面。８只高山姬鼠个体汇聚成独立的一支,中华姬鼠的３个个体也聚成一支,但大耳姬鼠却聚在中华姬鼠一支中,因此我们认为大耳姬鼠同中华姬鼠的分化时间可能比较晚近。     

有机磷化合物诱导的迟发性神经毒性的研究

很多有机磷化合物了易使人和动物产生急性事毒性,还能引发一种迟发性毒性,即“有机磷化合物诱导的迟发性多发性神经病”。本文综述了有关ＯＰＩＤＰ的症状学,病理学和生物化学的研究及其进展。     

Kinetics of retroviral production from the amphotropic ΨCRIP murine producer cell line

Rapidly expanding development and practice of gene therapy requires the availability of large quantities of high titer retroviral supernatants. One way to achieve high retroviral titers is through improved understanding of the kinetics of retroviral production and decay, and the subsequent development of improved cell culture methods. In the present study we investigated the effects of different operational modes on the retroviral production of the NIH 3T3 fibroblast derived amphotropic murine retroviral producing cell line pMFG/CRIP. Semi-continuous culture (exchange of 50% of medium volume daily) was found to promote cell growth and enhance retroviral production. The rapid medium exchange resulted in significantly larger amounts of high titer supernatants and an extended production phase as compared to the batch control cultures. The specific viral productivity of the pMFG/CRIP cells was in the range of 10 to 40 infectious viruses produced per thousand producer cells per day. The CV-1 African Green Monkey kidney cell line was used as the infection target. Lowering the serum level form 20% to 10% improved retroviral production slightly. However, at lower serum levels (1%, 5% and 10% (v/v)) growth of the producer cell line, and thus retroviral production, was directly proportional to the serum level. The half-life of the virus at 37°C was found to be 5.5 hours. Promoting the growth of producer cell lines can improve retroviral vectors titers and viral production. High cell density systems that allow for rapid cell growth and waste product removal are likely to be used to generate high-titer retroviral supernatants.     

酵母PH081在酸性磷酸酯酶基因表达调控中的作用

利用酵母ＰＨＯ８１与大肠杆菌产β－半乳糖苷酶的融合基因,系统地研究了ＰＨＯ８１基因在酵母酸性磷酸醋酶的不同调控因子的单缺失株和双缺失株中的表达规律,它与酸性磷酸酯酶基因ＰＨＯ５和ＰＨＯ１１的控制机制相似。构建了ＡＤＨ１启动子控制下ＰＨＯ８１表达质粒。在ＰＨＯ８１在细胞内组成型表达时,酸性磷酸酯酶基因的表达仍受无机磷的控制,揭示ＰＨＯ８１蛋白可能在不同浓度无机磷条件发生变构。ＰＨＯ８１在酸性磷酸酯酶基因表达系统中是一个中介因子。在此基础提出了一个酸性磷酸酯酶基因调控的分子模型。     

用蛋白质工程方法改变葡萄糖异构酶最适pH和最适温度

用寡核苷酸诱导的定点突变方法构建了葡萄糖异构酶基因的突变体（Ｎ１８４Ｄ和Ａ１９８Ｃ）。含突变体的重组质粒ｐＴＫＤ－ＧＩ１（Ｎ１８４Ｄ）和ｐＴＫＤ－ＧＩ２（Ａ１９８ｃ）在Ｅ．ｃｏｌｉＫ３８菌株中表达,用ＤＥＡＥ－Ｓｅｐｈａｒｏｓｅ ＦＦ和Ｓｅｐｈａｃｒｙｌ Ｓ－３００ＨＲ柱层析分离纯化突变酶。与野生型葡萄糖异构酶比较实验表明：（１）突变酶Ｎ１８４Ｄ的最适ｐＨ值下降了１个单位;等电点下降了０．６个单位     

包囊游仆虫休眠包囊的超微结构研究

包囊游仆虫休眠包囊中,各类纤毛器的纤毛基体上方的大部分纤毛杆退化,或仅保留毛基体,有时部分额腹棘毛的毛基体也瓦解消失。残留纤毛的纤毛杆周围微管和中央微管仍具有“9 2”结构特征,也有少数纤毛杆出现2套“9 2”微管共处于一层纤毛膜内的现象。毛基体中周围三联体微管的中央形成微管形结构聚合体,基体附属结构仅存在基体间连接及纤毛器托架的残余物;非纤毛区皮层表膜下未见微管层。纤毛区皮层含纤毛器腔周围微管层(相当于表膜下微管层)、纤毛器深部及附近的微管束和分散的微管群。并且,纤毛区皮层囊泡内含有呈不同形态的纤毛杆结构;大核核孔明显变大,核孔数目减少,核孔内膜附着染色质。     

几种细胞分裂素诱导石竹外植体直接再分化成花芽的机理

用ＭＳ＋２,４－Ｄ０．１ｍｇ／Ｌ为基本培养基,分别附加不同浓度的ＺＴ、ＢＡ和ＫＴ,对石竹的叶片、茎和花等外植体直接再分化成花芽的试验表明：叶片的外植体在有ＢＡ时可再分化出只有红色花瓣的不正常花芽;在含ＺＴ的培养基中再分化出具有１～２片叶或无叶的花芽,其花有两性花,雌花和仅单个雌蕊的不正常花,两性花可发育成结籽的果实;ＫＴ未能诱导花芽分化。茎外植体,３种ＣＴＫ都不能诱导出花芽。花等外植体仅在ＫＴ３ｍｇ／Ｌ的培养中再分化出无叶的不正常花芽,ＺＴ和ＢＡ的处理均不能诱导出花芽。     

c-fos expression in the amygdala:In vivo antisense modulation and role in anxiety

Summary 1. The amygdaloid complex is a key structure in mechanisms of fear and anxiety. Expression of the immediate-early gene c-fos has been reported in the central nucleus of the amygdala following various stressors, but the functional role of this phenomenon has remained unknown.2. c-fos expression was observed in the central nucleus when rats were subjected to a pharmacologically validated animal model of anxiety, the Vogel conflict test, but not after mere exposure to the test apparatus. Bilateral amygdala injection of a 15-mer phosphorothioate c-fos antisense oligodeoxynucleotide prior to testing blocked conflict-induced c-fos expression and had behavioral effects similar to those of established antianxiety drugs.3. Separate experiments determined that antisense treatment did not affect conflict behavior by acting on shock thresholds or drinking motivation.4. These findings provide evidence that neuronal activation and c-fos induction in the amygdala may be of importance for mechanisms of fear and anxiety.