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一个马铃薯Y病毒山东分离物的分离与鉴定 总被引:4,自引:1,他引:4
从具有典型花叶症状的马铃薯叶片中分离到马铃薯Y病毒(Potato virus Y,PVY)(本文称PVY-SD-TA分离物),扩繁后,提纯病毒,电镜下可观察到700~900 nm×11 nm的病毒粒体,病组织超薄切片观察可见风轮状的内含体结构,寄主反应特性研究表明其能侵染2科13种植物。SDS-PAGE电泳检测病毒编码的外壳蛋白亚基的分子量为33 kDa。以PVY-SD-TA基因组RNA为模板,应用RT-PCR方法和特异引物合成了外壳蛋白基因。对cDNA全序列分析表明,PVY-SD-TA CP基因核苷酸序列与N株系的同源性为96%,与GenBank中登录序列号为AJ390306的O株系分离物的同源性最高,为99%;与国内不同学者报道的PVY中国流行株的同源性分别为96%,97%和98%。通过以上生物学特性和分子水平的研究将PVY-SD-TA鉴定为普通株系(PVYO株系)。 相似文献
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淡紫拟青霉菌料防治大豆胞囊线虫的后效研究 总被引:6,自引:2,他引:6
淡紫拟青霉不同菌株的培养菌料,施225kg/hm2,对大豆胞囊线虫不但当年有45%~69%的较好防效,而且第2年和第3年仍然有22.5%~37.7%和7.3%~22.9%的后效,即空胞囊和被寄生的胞囊数量增加。 相似文献
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AIM: To explore the role of Akt signal pathway in apoptosis of neural cells in adult rats treated with Zuogui Pill, a Chinese medicine. METHODS: Flowcytometry and Western blotting methods were used to investigate the changes of cellular apoptosis rate and Akt signal pathway. RESULTS: Monosodium glutamate (MSG) could increase cellular apoptosis rate and significantly restrained the phosphorylation of Akt (Ser473) and Akt (Thr308), and markedly increased the levels of phospho-FKHR (ser256), GSK-3β (Ser9) and PTEN. Zuogui Pill partly inhibited the above effects of MSG. CONCLUSION: Zuogui pill effectively inhibits the neural apoptosis induced by MSG, and Akt pathway is involved in the neuronal protection of Zuogui pill. 相似文献
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Qiu-yan Chang Fu-cheng Guo Xue-rui Li Jian-hua Zhou Xuepeng Cai Qiuwei Pan Xiao-xia Ma 《Veterinary research communications》2018,42(4):309-313
Peste des petits ruminants virus (PPRV) causes highly contagious diseases in domestic and particular wild small ruminants, leading to substantial economic loss. The development of effective and cheap antiviral medications shall help to circumvent this emerging burden. In this study, we found that ribavirin, a competitive inosine-5’-monophosphate dehydrogenase (IMPDH) inhibitor, significantly inhibits the replication of PPRV. As IMPDH is a key enzyme in purine nucleotide synthesis, supplementation of exogenous guanosine attenuate the anti-PPRV effect of ribavirin. Interestingly, an uncompetitive IMPDH inhibitor, mycophenolic acid (MPA), exerted more potent antiviral effect again PPRV. Similarly, this effect was largely restored upon supplementation of guanosine. Thus, we have demonstrated that the IMPDH inhibitors ribavirin and MPA combat PPRV infection through purine nucleotide depletion. Because both regimens have been widely used in the clinic for treating viral infection or organ rejection in transplantation patients for decades, respectively, repurposing these existing safe and cheap medications may provide a new avenue for combating PPRV infection. 相似文献
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Effect of gut stress induced by oxidized wheat gluten on the growth performance,gut morphology and oxidative states of broilers 下载免费PDF全文
R. B. Liao H. J. Yan G. H. Liu S. Zhang W. H. Chang W. Liu C. H. Lin X. Y. Huang H. Y. Cai 《Journal of animal physiology and animal nutrition》2018,102(2):e849-e855
This study was to investigate the effect of oxidized wheat gluten (OG) on growth performance, gut morphology and its oxidative states of broilers. One hundred and eighty‐day‐old male broilers (10 chicks/pen) were randomly allocated into three dietary treatments: control diet (CON), diet with 8% wheat gluten (WG) and diet with 8% OG with six pens/treatment. Body weight (BW) (21 and 35 days) and average daily gain (ADG) (1–21 days and 22–35 days) decreased (p < .05) and feed conversion ratio (FCR) (1–21 days and 22–35 days) increased (p < .05) in OG treatment. Feed intake (FI) decreased (p < .05) in WG and OG treatments during 22–35 days. However, FI was not influenced by dietary treatments during 1–21 days (p > .05). The OG‐fed broilers had a lower faecal pH value (p < .05) and higher faecal moisture content (p < 05) at 14, 21, 28 and 35 days. Villus height, crypt depth and V/C value were not different (p > .05) among treatments at 21 and 35 days. Lipid peroxidation (LPO) (21 and 35 days) and malondialdehyde (MDA) (35 days) content in crop of OG treatment increased (p < .05). Oxidized glutathione (GSSG) (21 days), LPO (21 and 35 days) and MDA (21 and 35 days) content in ileum of OG treatment increased (p < .05). The reduced glutathione/oxidized glutathione (GSH/GSSG) (21 days) and (GSH) (35 days) in ileum of OG treatment decreased (p < .05). The present findings indicate that OG might be a stressor for broiler gut, which could induce oxidative stress both in crop and in ileum, and the diarrhoea as well. The growth performance of broiler was consequently depressed. 相似文献
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Multimarker and rare variants genomewide association studies for bone weight in Simmental cattle 下载免费PDF全文
J. Miao X. Wang J. Bao S. Jin T. Chang J. Xia L. Yang B. Zhu L. Xu L. Zhang X. Gao Y. Chen J. Li H. Gao 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(3):159-169
Bone weight, defined as the total weight of the bones in all the forequarter and hindquarter joints, can reflect somebody conformation traits and skeletal diseases. To gain a better understanding of the genetic determinants of bone weight, we used a composite strategy including multimarker and rare‐marker association to perform genomewide association studies (GWAS) for that character in Simmental cattle. Our strategy consisted of three models: (i) A traditional linear mixed model (LMM) was applied (Q+K‐LMM); (ii) single nucleotide polymorphisms (SNPs) with p‐values less than .05 from the LMM were selected to undergo the least absolute shrinkage and selector operator (Lasso) in the second stage (LMM‐Lasso); (iii) genes containing two or more rare SNPs were examined by performing the sequence kernel association test (gene‐based SKAT). A total of 1,225 cattle were genotyped with an Illumina BovineHD BeadChip containing 770,000 SNPs. After the quality‐control procedures, 1,217 individuals with 608,696 common SNPs and 105,787 rare SNPs (with 0.001 < minor allele frequency [MAF] <0.05) remained in the sample for analysis. A traditional LMM successfully mapped three genes associated with bone weight, while LMM‐Lasso identified nine genes, which included all genes found by traditional LMM. Only a single gene, EPHB3, surpassed the significance threshold after Bonferroni correction in gene‐based SKAT. In conclusion, based on functional annotation and results from previous endeavours, we believe that LCORL, RIMS2, LAP3, PRKAR2B, CHSY1, MAP2K6 and EPHB3 are candidate genes for bone weight. In general, such a comprehensive strategy for GWAS may be useful for researchers seeking to probe the full genetic architecture underlying economic traits in livestock. 相似文献