水溶性肥料的发展研究进展

近年来水溶性肥料发展迅速,前景十分广阔。简单介绍了水溶性肥料的分类及发展状况,分析了水溶性肥料的生产工艺及特点,并对水溶性肥料的未来发展提出了一些建议。     

PE基木塑复合材料弹性模量的动态测量

采用"悬臂梁"自由端的方式测定PE基木塑试材的动态弹性模量.结果表明,PE基木塑复合材料的动态弹性模量性能高于木材、麦秸板和密度板等弹性材质,但低于定向刨花板等结构木质复合材料;采用振动法测量木塑复合材料的动态弹性模量具有快速、简便、重复性好等优点.     

基于(24,12)扩展Golay码的信息协调协议

基于(24,12)扩辰Golay码结合奇偶校验和提出了一种新的信息协调协议,对此协议的安全性做了分析.     

《基础会计学》教学内容改革探讨

针对基础会计教学中的记账方法、记账凭证及日记账的设置等内容陈旧、落后问题进行了探讨,旨在删减、统一及规范会计的记账方法、记账凭证及日记账的设置,使会计核算内容更适应现代市场经济的发展,尽快与国际接轨.     

补充寄主提高林间松毛虫卵寄生率的研究

研究表明:在松林内,14种松毛虫卵寄生蜂中有9种能寄生柞蚕卵。利用柞蚕卵作为马尾松毛虫卵寄生蜂的补充寄主是可行的。补充寄主的林地,卵蜂种群密度比对照提高0.68～1.43倍,而长年补充又比阶段补充增加1.37倍,比对照区增加2倍。林间补充寄主后提高了平腹小蜂和白角小蜂的种群密度。第一代松毛虫卵期总寄生率补充寄主区较对照区提高5.16～28.96％,第二代提高3.62～24.97％;第三代提高8～17.99％。根据卵蜂在不同生态条件下的消长规律,补充寄主的方法应有所不同,在地被物稀少的松林中补充寄主的次数应多一些,而在地被物丰富的松林中,补充寄主的次数可相应减少。     

鸡CD4蛋白基因的克隆及其mRNA在淋巴器官中的表达

从鸡胸腺、脾脏、哈德氏腺、外周血液和法氏囊等免疫器官中分离淋巴细胞,应用RT-PCR对这些免疫器官中鸡CD4分子mRNA的表达进行了研究。同时,用RT-PCR对鸡脾淋巴细胞CD4分子cDNA进行了克隆和序列测定。结果表明,在上述器官中,法氏囊淋巴细胞不表达鸡CD4分子mRNA,其他器官中均有表达。通过序列分析表明,本试验扩增得到的基因为编码鸡CD4分子的基因。     

苦马豆素人工抗原免疫山羊的安全性试验

试验通过分析疯草毒素人工抗原(疫苗)SW BSA免疫山羊时对机体肝功、肾功的影响,进行安全性评价。将30只羊随机分为对照组(6只)、免疫A组(12只)、免疫B组(12只),免疫组依次进行基础免疫、首免、加强免疫,每次免疫前进行采血,分析血清中谷丙转氨酶(GPT)、谷草转氨酶(GOT)、尿素氮(BUN)、α苷露糖苷酶(AMA)、碱性磷酸酶(AKP)、乳酸脱氢酶(LDH)的变化,同时检测尿液中有无SW。结果表明,免疫组与对照组的血清GPT、GOT、BUN、AMA、AKP、LDH差异均不显著(P>0.05),尿液中未检查出SW。     

六六六在生态环境中的行为特征与起用林丹的科学依据

本文根据80年代初中国生态环境中六六六的污染概况,特别是六六六各异构体在植物、动物样品中的残留水平,在土壤中的消解、被作物吸收和在食物链中生物浓缩的特     

猪泛素基因与PRRSV GP5基因融合表达质粒的构建及其免疫效果

构建了泛素（ubiquitin，Ub）基因与密码子优化的PRRSVGP5蛋白（optiGP5）基因融合表达质粒pIR—Ub—optiGP5。间接免疫荧光和Western—blot分析表明，重组质粒转染293T细胞后能够瞬时表达。将pIR—optiGP5和pIR—Ub—optiGP5两种质粒DNA肌肉注射免疫BALB／c小鼠后，分别检测小鼠血清中抗GP5抗体、T淋巴细胞的增殖能力以及CTL活性。结果显示，pIR—optiGP5质粒免疫组在二免后可以检测到荧光抗体，而pIR—Ub—optiGP5质粒免疫组一直未检测到抗GP5抗体，但该免疫组的T淋巴细胞增殖指数及针对GP5的特异性CTL反应数值明显高于pIR—optiGP5质粒免疫组。这表明泛素与GP5的融合表达可增强细胞免疫反应。     

Isolation and Identification of a Variant Porcine Epidemic Diarrhea Virus and the Immune Efficacy of Its Inactivated Vaccine

This study was aimed to isolate a mutant strain of porcine epidemic diarrhea virus and prepare a PEDV inactivated vaccine with high valence by suspension culture process for immunizing against PEDV effectively in China.200 small intestines and theirs contents of diarrhea piglets died of diarrhea,collected from many large-scale pig farms in China,were detected by RT-PCR and sequenced,a mutant strain of porcine epidemic diarrhea virus was selected and put on the suspension-cultured Vero cells in a 2 L reactor for virus isolation and continuous cell culture,the harvested virus suspension,which was identified and determined TCID₅₀,was inactivated by formaldehyde and mixed with aluminum hydroxide gel adjuvant to prepare PEDV inactivated vaccine.After its physical behavior,stability viscosity,sterility test were checked out,the safety and immune efficacy were studied by immunizing the pregnant pigs and theirs piglets.The results were as follows:86 samples were detected positive in 200 samples,cytopathy occurred after the mutant strain samples screened were passaged to 5th generation,the virus suspension was harvested in 10th generation and identified as a mutant strain of PEDV,named PEDV-GF10 strain.The virus titer of harvested virus suspension was measured up to 1×10^8.0 TCID₅₀/mL after concentrated.After the vaccine was checked out,the sows,40 and 25 days before delivery in experimental groups,were injected into Xuehai acupoint with 4 mL vaccine and the pigs in blank group were free of immunifications.The results showed that there were no obvious differences in the production status of the sows in experimental groups and blank group and the temperature of theirs 3-day-old healthy piglets injected different doses of vaccine,and the vaccine was safe to the sows and piglets.Forty 3-day-old piglets producted by pregnant sows in experimental groups and blank group were randomly selected and taken 4 mL 1×10^8.0TCID₅₀/mL F10 virus culture.The PEDV morbidity of piglets in blank group was 100% after injection and the antibodies were negative;10% piglets in blank group had mild diarrhea symptoms,the protection rate was up to 90%,antibody of passive immunity in piglets lasted for more than 35 days.Virus titer of mutant strain of PEDV-GF10 improved a lot by suspension cell culture,the PEDV-GF10 inactivated vaccine was safe,and could effectively prevent and control the variation strain of PEDV in China.