PEDV和TGEV双基因共表达载体pVAXD-PS1-TS的构建及体外表达

采用RT-PCR扩增猪传染性肠胃炎病毒（TGEV）SC-H株S基因N端主要抗原位点片段（大小约为1 916bp）和猪流行性腹泻病毒（PEDV）SC-L株S1基因（大小约为2 367bp）,插入pMDl9-T simple载体,经酶切与测序鉴定后,构建重组质粒pMD19-T-TS与pMD19-T-PS1。从T载体上将PS1、TS基因切下,以亚克隆方法插入双启动子真核表达载体pVAXD,构建能同时表达TGEV S基因和PEDV S1基因的重组质粒pVAXD-PS1-TS。对重组质粒进行PCR与酶切鉴定后,以脂质体转染法转染COS7细胞,间接免疫荧光检测转染后细胞外源基因的表达情况。结果表明,重组质粒构建正确且能够在COS7细胞中得到表达,转染的细胞呈现特异性荧光。真核表达质粒pVAXD-PS1-TS的成功构建为进一步研究PEDV和TGEV的二联核酸疫苗奠定了基础。     

Effect of SAPK/JNK signal pathway on neuronal apoptosis in cerebral infarction rats

AIM: To investigate the molecular mechanism of neuronal apoptosis by observing the changes of key proteins in SAPK/JNK and Bcl-2/Bax signal pathways after brain infarction. METHODS: The cortical infarction was induced by photochemistry, namely photothrombotic cortical injury (PCI). Thirty-six Sprague-Dawley rats were randomly divided into 2 groups: PCI group and sham-operated group. The ipsilesional cortex was harvested for histomorphometry and transmission electron microscopy 7 days after PCI. Some key proteins including p-JNK1, p-JNK2, p-c-Jun, p-ATF-2, total JNK1, total JNK2, Bcl-2 and Bax were detected by Western blotting analysis.RESULTS: The cortical infarction in rats was successfully induced by photochemistry. The apoptosis of neurons in cortex was more obvious in PCI group than that in sham-operated group 7 days after PCI. The levels of p-JNK1, p-JNK2, p-c-Jun and p-ATF-2 in PCI group were significantly higher than those in sham-operated group, whereas the ratio of Bcl-2/Bax was significantly lower(P<0.05). CONCLUSION: Apoptosis is a major contributor to neuronal loss induced by cerebral hypoxia-ischemia for a long period after cortical infarction. The process is related to some apoptotic proteins such as Bcl-2/Bax and the SAPK/JNK signal pathways activated by ischemic injury.     

产犊季节、胎次及牛场对荷斯坦牛泌乳性能的影响

本研究收集了3个千头以上奶牛场共8872条相关信息,采用多因素方差分析法分析了不同产犊季节、胎次和牛场对泌乳天数、305d校正奶量、305d脂肪产量、305d蛋白产量和全泌乳期产奶量5个泌乳性能指标的影响。结果表明,不同产犊季节、胎次和牛场都极显著影响奶牛的该5项泌乳性能（P〈0．01）。夏季和秋季产犊奶牛的泌乳性能较为理想。夏季产犊奶牛的泌乳天数和全泌乳期产奶量最高,其他三个泌乳性能指标都位居第二;秋季产犊奶牛的305d校正奶量、脂肪产量和蛋白产量都显著高于其他三个季节（P〈0．05）,泌乳天数和全泌乳期产奶量也仅次于夏季。头胎牛的各项泌乳性能都显著高于其他胎次的奶牛（P〈0．05）,其次为2胎产犊奶牛。随着胎次的增加,泌乳性能的各项指标都有不同程度的降低。不同的牛场极显著地影响奶牛的泌乳性能（P〈0．01）。     

提高华山松种子园开花结实量试验研究

通过对贵州平坝华山松种子园开花结实量的调查和对其土壤、针叶养分分析,掌握其低产的原因后,采取施N、P、K肥、B肥、去劣疏伐和修枝整形等增长技术措施,可提高种子园种子单产10%以上.     

略论开放我国黄金市场的必要性和可行性

针对当代黄金市场具有金融与贸易的双重特性,运用金融与贸易市场理论,分析了开放我国黄金市场的必要性,说明了开放黄金市场有利于稳定物价,完善我国金融市场、保持中国最适度黄金储备量,并且有利于黄金的生产和管理.同时分析了我国目前已具备开放黄金市场的条件.最后对开放我国黄金市场提出了若干具有可操作性的建议.     

Study on Biological Characteristics and Drug Sensitivity of Haemophilus parasuis Isolated in Sichuan Province

The study was aimed to investigate the biological characsteristics and drug sensitive tests of Haemophilus parasuis isolated in Sichuan province.This paper reported the biological characteristics,16S rRNA gene PCR and drug sensitive test of the isolates by technique of microbiological and molecular biology.The results showed that the isolates had micro anaerobic and could produce satellite phenomenon,the isolates were just same in biochemical characteristics with field isolates in other area.All the isolates amplified 821 bp 16S rRNA gene.And drug sensitive tests showed that the isolates were highly sensitive to cefradine,ampicillin,cefradine,amoxicillin,cefaclor,ofloxacin,cefotaxime and furadantin,the sensitive rate was 75.61% to 87.80%,but the isolates were high resistance to lincomycin,carbenicillin,enrofloxacin,amikacin and sulfamethoxazole,and multiple-drug resistance was found among the isolates,the number of bacterial strains resistant to antibiotics were more between five and eight,the resisitance strains were 21.95% to 30.49%,7 isolates were even resistant to 13 antibiotics.The results showed the phenomenon of drug resistance of the isolates was very serious.