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41.
Based on the complete genome sequence of Newcastle disease virus (NDV) ZJI strain, seven pairs of primers were designed to amplify a cDNA fragment for constructing the plasmid pNDV/ZJI, which contained the full-length cDNA of the NDV ZJI strain. The pNDV/ZJI, with three helper plasmids, pCIneoNP, pCIneoP and pCIneoL, were then cotransfected into BSR-T7/5 cells expressing T7 RNA polymerase. After inoculation of the transfected cell culture supernatant into embryonated chicken eggs from specific-pathogen-free (SPF) flock, an infectious NDV ZJI strain was successfully rescued. Green fluorescent protein (GFP) gene was amplified and inserted into the NDV full-length cDNA to generate a GFP-tagged recombinant plasmid pNDV/ZJIGFP. After cotransfection of the resultant plasmid and the three support plasmids into BSR-T7/5 cells, the recombinant NDV, NDV/ZJIGFP, was rescued. Specific green fluorescence was observed in BSR-T7/5 and chicken embryo fibroblast (CEF) cells 48h post-infection, indicating that the GFP gene was expressed at a relatively high level. NDV/ZJIGFP was inoculated into 10-day-old SPF chickens by oculonasal route. Four days post-infection, strong green fluorescence could be detected in the kidneys and tracheae, indicating that the recombinant GFP-tagged NDV could be a very useful tool for analysis of NDV dissemination and pathogenesis.  相似文献   
42.
Effects of doubled CO2 and O3 concentration on Soybean were studied in open-top chambers (OTC). Under doubled CO2 concentration, grain yield and biomass increased, the SOD activity, vitamin C (Vc) and carotenoid (Car) content also increased; Superoxide (O2-) generating rate decreased, relative conductivity and malondialdehyde (MDA) content significantly declined. But under doubled O3 concentration, the SOD activity, Vc and Car contents declined, resulting in imbalance of activated-oxygen production, enhanced O2- generating rate and accelerated process of lipid peroxidation and increase in MDA content and ion leakage of leaves. The final result was decreased grain yield and plant biomass. Interactive effects of doubled CO2 and O3 concentrations on soybean were mostly counteractive. However, the beneficial effects of concentration-doubled CO2 are more than compensate the negative effects imposed by doubled O3, and the latter in its turn partly counteracted the positive effects of the former.  相似文献   
43.
目的:建立SV40病毒在Vero细胞上培养的方法,观察其生长过程,获得SV40病毒,并建立相应的SV40病毒检测方法,为SV40灭活疫苗的制备奠定良好的基础。方法:在Vero细胞上培养和增殖SV40-776株病毒。收获病毒后,应用PCR、免疫荧光以及克隆特异性片段进行测序比较来鉴定SV40病毒。结果:SV40在Vero细胞中增殖很快,并且使细胞出现明显的病变。小规模分离到了SV40病毒颗粒,获得了病毒DNA。不同的鉴定方法均显示出良好的特异性。结论:探讨了SV40病毒病变的基本过程,建立了病毒的培养、增殖和鉴定的方法。  相似文献   
44.
Five species of higher marine fungi were observed on the incubated drift and intertidal woods collected from the coasts of Yellow Sea and Bohai Sea. Among them, Halosphaeriopsis was a genus newly recorded for China. Taxonomy and morphology of these species were discussed in this paper. The specimens were deposited in Mycology Herbarium at Qingdao Agricultural University (MHQAU).  相似文献   
45.
Clonostachys phyllophila and Clonostachys rogersoniana were isolated from rhizosphere soil of Allium tuberosum in Chaoyang, Liaoning Province. It is the first report of the genus in China. The species was described morphologically and illustrated in this paper, the culture was stored in the Culture Collection of Liaoning Center of Culture Collection (LCCC).  相似文献   
46.
桃儿七成熟胚的离体培养研究   总被引:5,自引:0,他引:5  
以MS为基本培养基,通过添加不同激素和附加物等措施对桃儿七种子成熟胚进行了无菌苗和愈伤组织诱导初步研究。研究结果表明:0.5mg/L IAA+0.2mg/L KT+0.3mg/L GA3处理可获得生长良好的无菌苗,诱导率达41.67%。1.0mg/L 2,4-D+0.4mg/L KT+0.3mg/L GA3处理愈伤组织诱导率可达36.67%,添加500mg/L水解酪蛋白(CH)或10mg/L D-生物素有益于愈伤组织的诱导。光照和变温培养有利于提高无菌苗和愈伤组织的诱导率,有效降低褐化率。  相似文献   
47.
Applications of proteomics in hepatic diseases research   总被引:2,自引:0,他引:2  
Since the completion of human genome draft in the process of Human Genome Project (HGP), life science has entered the post-genome era in the early 21st century. Proteomics has become an important part in the leading research area and been applied in many fields of life science such as the occurrence and de-velopment of tumor, cell differentiation and embryo-genesis, mechanisms of gene regulation, mechanisms and therapy of major diseases, pharmacy, relationship between environment and health …  相似文献   
48.
RAP-PCR是以PCR为基础构建RNA指纹图谱,研究基因差异表达的有效方法.所显示的种系特异性差异可用于对基因的遗传作图;所揭示的组织特异性差异可用于研究特异基因的表达.该法可检测各种情形下RNA群体间的差异.本文简介其基本原理及在基因差异表达研究领域的最新应用。 Abstract:RAP-PCR is a useful method based on PCR to display fingerprint of RNA populations and to study differential gene expression.The strain-specific differences revealed should be useful for genetic mapping of genes.The tissue-spe-cific differences revealed might be useful for studying differential gene expression.In this review,we introduce the theory of RAP-PCR and its recent applications.  相似文献   
49.
中国成都地区汉族人群DHFRP2位点的遗传多态性研究   总被引:4,自引:0,他引:4  
用扩增片断长度多态性技术分析短串联重复序列(STR)DHFRP2位点的DNA多态性, 在156个中国成都地区汉族无关个体中发现6个等位基因,19种基因型,并首次发现一重复单元数不是4的整数倍的等位基因,该等位基因按孟德尔遗传规律遗传。观察的基因型分布符合Hardy-Weinberg定律,其个人鉴别力(DP)为0.87,杂合度为67.3%,多态性信息量(PIC)为0.68,非父排除率(CE)为45.5%,家系分析结果表明, 该位点符合孟德尔遗传法则。 Abstract: Analyzes polymorphism of short tandem repeat locus (DHFRP2) by using Amp-FLP. Six alleles and nineteen genotypes were observed in 156 unrelated individuals of Chinese Hans in Chengdu. Meanwhile, we first discovered a new allele, its repeat monomers is not integral times of four, which is in conformity with Mendelian inheritance. The allelic discriminating power (DP), observed heterozygocity (h), polymorphism information content (PIC) and chances of paternity exclusion (CE) are 0.87, 67.3%, 0.68 and 45.5% respectively. The distribution of its genotypes tally with Hardy-Weinberg equilibrium and family study manifested that the locus is in conformity with medelian inheritance.  相似文献   
50.
Although microRNAs(miRNAs) have been intensively studied in cardiac fibrosis,their roles in drug-mediated anti-fibrotic therapy are still unknown.Previously,Pioglitazone attenuated cardiac fibrosis and increased miR-711 experimentally.We aimed to explore the role and mechanism of miR-711 in pioglitazone-treated myocardial infarction in rats.Our results showed that pioglitazone significantly reduced collagen-I levels and increased miR-711 expression in myocardial infarction heart.Pioglitazone increased the expression of miR-711 in cardiac fibroblasts,and overexpression of miR-711 suppressed collagen-I levels in angiotensin II(Ang II)-treated or untreated cells.Transfection with antagomir-711 correspondingly abolished the pioglitazone-induced reduction in collagen-I levels.Bioinformatics analysis identified SP1,which directly promotes collagen-I synthesis,as the putative target of miR-711.This was confirmed by luciferase assay and western blot analysis.Additionally,increased SP1 expression was attenuated by pioglitazone in myocardial infarction heart.Furthermore,transfection of antagomir-711 attenuated pioglitazone-reduced SP1 expression in cardiac fibroblasts with or without Ang II stimulation.We conclude that pioglitazone up-regulated miR-711 to reduce collagen-I levels in rats with myocardial infarction.The miR-711-SP1-collagen-I pathway may be involved in the anti-fibrotic effects of pioglitazone.Our findings may provide new strategies for miRNA-based anti-fibrotic drug research.  相似文献   
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