外源性环核苷酸对AA肉鸡脂肪和蛋白质代谢的影响

选用初生健康AA肉鸡 2 4 0只 ,随机分为 2组 ,每组 12 0只 ,每组内设 3个重复 :I组为试验组 ,每隔 4d皮下注射标准环核苷酸组合剂 ,剂量为每只鸡 0 1mL ;Ⅱ组为对照组 ,注射等量的生理盐水 ,共计 4 9d。研究结果表明 ,试验组鸡肝脏组织中总RNA、mRNA分别比对照组提高2 9 84 %和 2 6 0 3%。经单因子方差分析 ,组间均存在着显著差异 (P <0 0 1) ,血浆中cAMP和cGMP的浓度显著高于对照组 (P <0 0 1) ;血清中生长激素浓度升高 37 70 % ,球蛋白浓度提高了 34 0 9% ,甘油三酯浓度显著高于对照组 (P <0 0 1) ,尤其GOT、GPT等酶活性均有显著提高 (P <0 0 1)。     

禽流感病毒NP cDNA反义逆转录病毒载体的构建及重组病毒的鉴定

根据反义ＲＮＡ作用原理,以禽流感病毒（ＡＩＶ）Ｈ１４Ｎ５　ｃＤＮＡ全长及５’端２３５个ｂｐ为目的基因,反向插入反转录病毒载体 ｐＬＸＳＮ中,命名为 ｐＬＸＳＮ－ＮＰ及 ｐＬＸＳＮ－ＮＰ,用脂质体包裹重组质粒转染包装细胞 ＰＡ３１７,Ｇ４１８筛选抗性克性,扩增单个克隆后提取包装细胞上清的病毒ＲＮＡ（ｖＲＮＡ）,以巢式ＰＣＲ方法检测,以及用包装细胞上清（重组病毒）感染滴定细胞系ＮＩＨ３Ｔ３,表明已筛选出产毒的的克隆细胞质,得到重组逆转录病毒,为反义ＲＮＡ抑制禽流感病毒复制的实验研究奠定了物质基础。     

Large Scale Evaluation of Primers for Diagnosis of Rupestris Stem Pitting Associated Virus-1

The unavailability of adequate immunological reagents has prevented the use of ELISA for the diagnosis of rupestris stem pitting disorder of grapevines. In this work, the performance of five primer pairs for broad-scale detection of rupestris stem pitting associated virus-1 by RT-PCR using ds-RNA templates was compared and contrasted with biological indexing. The virus was widespread among the budwood of 35 Portuguese grapevine varieties assayed, with a prevalence of 85%. The biological assay proved to be unreliable as an index of infection due to the high number of false negatives. Five sets of primers were assayed and compared by means of their relative sensitivity and negative predictive value. The primer pair specific for the coat protein gene was excluded because of the difficulty in identifying the specific amplified product. From the other four primer pairs, those specific for the helicase domain of the putative polymerase gene had the highest sensitivity and negative predictive value. However, a high confidence in the assay, as desirable for a certification scheme, could not be obtained by the sole use of this primer pair. An additional pair should be used in a separate or in a multiplex RT-PCR reaction.     

Comparative Analysis of Japanese and Foreign Strains of <Emphasis Type="Italic">Ralstonia solanacearum</Emphasis> Based on 16S Ribosomal RNA Gene Sequences

We determined nearly the complete sequences of the 16S ribosomal RNA gene (rDNA) for Japanese strains of R. solanacearum. The comparison of 1471 nucleotide positions separated the Japanese strains into two groups, group 1 with biovars 1, 2, 3 and 4 strains which belonged to race 1, and group 2 with biovar 2 strains corresponding to race 3. Group 1 strains all had identical sequences, and strains representing the four biovars within the group did not differ from each other. Group 2 strains had characteristic nucleotides which differed at seven positions from group 1 strains. Comparative analysis of Japanese and foreign strains based on 16S rDNA sequences showed that Japanese group 1 was closely related to Asian and Australian biovars 3, 4 and 5, and belonged to the known division 1. Japanese group 2 was homogeneous to Indonesian biovars 2 and N2 in subdivision 2b. Since the differences in the nucleotides corresponded to restriction sites for the AluI, RFLP analysis of PCR-amplified 16S rDNA efficiently differentiated not only Japanese group 1 from group 2, but also differentiated three types of foreign strains which differed in biovar and geographic origin. Received 26 July 1999/ Accepted in revised form 19 November 1999     

Nested PCR检测狂犬病病毒方法的建立及病毒在小鼠体内的移行动态

应用建立的Nested PCR特异地检出狂犬病病毒株CVC、HEP-Flury、ERA、RC-HL、1008、Komatsug-awa的RNA,但对类狂犬病病毒Lagos bat、Duvenhage、Mokola及水泡性口膜炎病毒、轮状病毒、犬瘟热病毒均为阴性。该法敏感性很高,能检出3 TCID50或0.8pg的狂犬病病毒RNA。用该法测定了小鼠脑内感染CVS株后的病毒增殖和移行动态,对感染小鼠的主要内脏器官进行了病毒RNA检测,结果发现小鼠脑内感染CVS 5 d以后在其心、肝、脾、肺等内脏器官均检出了病毒RNA。     

龙眼胚性愈伤组织体胚发生的同步化调控及其DNA与RNA的提取方法

过改进培养基的配方,控制2,4-D和蔗糖浓度以及培养时间,获得了龙眼胚性愈伤组织体胚发生各个阶段即球形胚、心形胚、鱼雷形胚、子叶形胚、成熟体胚等阶段高度同步化的胚性培养物;对龙眼胚性培养物进行了DNA、RNA提取方法研究,获得了完整、高质量的DNA和RNA,摸索出一套简便、快捷、有效的DNA提取方法,并对提取的RNA进行了反转录及PCR扩增试验,为龙眼体细胞胚胎发生的分子生物学研究奠定了重要基础。      

RNA干涉及其抗病毒应用研究进展

综述RNAi的机制,植物与病毒相互作用的机制,及RNAi在植物抗病毒育种中的应用研究进展,并展望其研究前景。     

小RNA的研究进展

概述了小RNA的发现过程,介绍了小RNA的特征、功能、作用机制,并对其研究进行展望,以期为小RNA的研究提供参考。     

1949~2008年农业经济研究计量考察

借助《中国学术期刊网络出版总库》文献检索工具,对1949~2008年4个历史时期的农业经济类期刊论文进行了统计分析,结果发现：新中国成立60年来,围绕农业与农村社会发展展开的农业经济研究始终紧扣中国农业经济发展实践进行,先后经历了起步、初步发展、停滞、继续发展与繁荣4个历史阶段。从对农业经济类论文总量、分类和内容3个视角的统计分析中可看出,农业经济研究在不同历史时期具有不同的特点和规律。     

椰衣提取物总酚含量及抗氧化活性研究

[目的]测定椰衣不同提取物的总酚含量,考察椰衣不同提取物的抗氧化活性。[方法]采用不同极性的溶剂对椰衣粉的60%乙醇提物进行萃取,得到石油醚、乙酸乙酯、正丁醇和水等4个提取物,以清除l,l-二苯基-2-三硝基苯肼(DPPH)自由基的能力评价椰衣提取物的抗氧化活性,并采用Folin-Ciocalteu法测定提取物中总酚含量。[结果]椰衣各提取物均有不同程度的抗氧化能力,顺序为正丁醇提取物乙酸乙脂提取物水提物石油醚提取物。[结论]椰衣不同提取物均具有抗氧化能力,其与酚类物质含量基本呈正相关,其乙酸乙酯提取物和正丁醇提取物具有较强的抗氧化活性。