酸化法处理宁南霉素发酵液灭活的实验研究

宁南霉素是一种广谱、高效、低毒、低残留的无公害生物农药,其生产菌是诺尔斯链霉菌西昌变种,传统生产菌用高温加热处理.首次报道了酸化法杀灭宁南霉素发酵液中活菌丝体的实验室方法.通过模拟工业生产后处理过程,分别用浓硫酸、浓盐酸、草酸作为酸化剂展开杀灭活菌丝体的实验,3种酸最佳反应条件均为pH值在2.0-2.5间,酸化时间为60 min,但浓硫酸成本最低为最佳酸化剂.实验结果表明酸化处理液过滤速度快,而且不会影响宁南霉素的生物效价及产品稳定性.     

光催化-生化联合法处理难生物降解废水的研究进展

综述了光催化-生化联合法处理农药废水、印染废水等难生物降解废水的研究进展,展望了光催化-生化联合法处理技术的发展前景,并提出了今后的研究方向。     

microRNA: 一种潜在新型诊断结核病的生物标志物

为了阐述miRNA作为新型生物标记物在结核病诊断中的潜在应用的可能性和优势,文章对结核病的流行态势、诊断现状以及结核病中特异表达miRNA的研究进展了进行总结.结核病的高感染率、高死亡率及耐药菌株的出现严重威胁人类公共卫生事业.现有的结核病诊断技术无法满足快速、低成本、非侵袭性并易推广的诊断要求.miRNA作为一种新的诊断疾病的生物标志物已经在癌症、心脏疾病、妊娠、糖尿病、精神疾病以及多种感染性疾病等领域有研究.大量研究结果显示,在结核病人体内miRNA 21、miRNA 29a、miRNA 99b、miRNA 125b、miRNA 144和miRNA 144*、miRNA 155、miRNA 424表达上调,miRNA 142 3p、miRNA 146表达下调,而miRNA 223及miRNA let 7家族在结核病人不同部位表达存在差异.     

一类食饵具有常数存放率的Kolmogrov生态系统

本文讨论了一类食饵具有常数存放率的Kolmogorov生态系统在第一象限可行平衡点的全局稳定性、正平衡点的全局稳定性条件以及围绕正平衡点极限环的存在唯一性.并对所得结论给予了生物解释.     

低压静电对活性污泥絮体物理特性的影响

本研究采用静电处理技术以改善活性污泥絮体的物理特性，以提高活性污泥的沉降性和脱水性。结果表明静电场对污泥颗粒的电位有明显的降低作用；随着静电场电流的增加，污泥颗粒的电位降低，电流１００ｍＡ为稳定转化点。当电流为１００ｍＡ时，生物絮体的物理特性最佳，这些结果对活性污泥法处理系统的改善有重要意义。     

Character and OTU stability in five taxonomic groups

The character and OTU stability of classifications based on UPGMA clustering and maximum parsimony (MP) trees were compared for 5 datasets (families of angiosperms, families of orthopteroid insects, species of the fish genusIctalurus, genera of the salamander family Salamandridae, and genera of the frog family Myobatrachidae). Stability was investigated by taking different sized random subsamples of OTUs or characters, computing UPGMA clusters and an MP tree, and then comparing the resulting trees with those based on the entire dataset. Agreement was measured by two consensus indices, that of Colless, computed from strict consensus trees, and Stinebrickner's 0.5-consensus index. Tests of character stability generally showed a monotone decrease in agreement with the standard as smaller sets of characters are considered. The relative success of the two methods depended upon the dataset. Tests of OTU stability showed a monotone decrease in agreement for UPGMA as smaller sets of OTUs are considered. But for MP, agreement decreased and then increased again on the same scale. The apparent superiority of UPGMA relative to MP with respect to OTU stability depended upon the dataset. Considerations other than stability, such as computer efficiency or accuracy, will also determine the method of choice for classifications.     

钝齿棒状杆菌转导噬菌体T-1的理化和生物学特性

虽然对谷氨酸产生菌(Corynebacterium crenatum)噬菌体已有许多较深入的研究,但对于噬菌体在遗传学上的应用的研究却很少。为寻找适合于谷氨酸产生菌的遗传载体,本实验室从分离出的48株噬菌体中,筛选后得到两株具有转导能力的噬菌体。下文报道其中一株的理化、生物学特性,为已发表的谷氨酸产生菌噬菌体进行比较,提供选择转导噬菌体的参考。     

Robust regression in biological assay: application to the evaluation of alternative experimental techniques

Summary Robust Huber type regression and testing of linear hypotheses are adapted to statistical analysis of parallel line and slope ratio assays. They are applied in the evaluation of results of several experiments carried out in order to compare and validate alternatives to animal experimentation based on embryo and cell cultures. Computational procedures necessary for the application of robust methods of analysis used the conversational statistical package ROBSYS. Special commands for the analysis of parallel line and slope ratio assays have been added to ROBSYS.     

香豆素烟酸酯的合成及生物活性研究

以烟酸和香豆素为原料,通过缩合剂法合成香豆素烟酸酯。经过核磁共振氢谱、质谱确证目标化合物的化学结构。考察影响因素(反应溶剂、反应温度、反应时间、缩合剂种类)对酯化产物收率的影响,优选出最佳合成工艺。最佳合成工艺为反应温度为25℃、反应时间为24 h、最佳溶剂为乙腈、采用DCC/DMAP为缩合剂,生物活性测试表明,新合成的烟酸香豆素酯对肿瘤细胞具有一定的抑制作用。     

河流水域有机污染的生物学监测与评价

河流水域污染后影响到底栖动物、浮游生物和微生物的个体数量和重量,根据其水体个体数量的变化,可监测、评价水体污染程度。本文通过对我市迎江区长枫港水体的大型底栖无脊椎动物,浮游生物和微生物的监测,根据水体出现特有的指示生物来判别水体污染状况。