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ZHANG Hai ZHOU Bi-jun YANG Zhong-cheng LIAO Mei WANG Kai-gong WEN Ming CHENG Zhen-tao WANG Wei FENG Xu-fang 《中国畜牧兽医》2016,43(11):2834-2843
In order to study and analyze L1 gene of bovine papillomavirus(BPV)in Guizhou province,the L1 gene of BPV-GZ01 strain was amplified,cloned and sequenced using bioinformatic softwares and methods,and the secondary structure,tertiary structure,B-cell preponderant epitope,conserved domains analysis, transmembrane domain and signal peptide of L1 gene were predicted.The results showed that the length of L1 gene was 1 494 bp,encoding 497 amino acids.The L1 gene of BPV-GZ01 strain shared an amino acid identities of 98.6%,99.4%,98.4%,94.4% and 91.3%,and a nucleotide identities of 99.1%,99.8%,99.4%,87.6% and 82.8% with those of BPV2,BPV2-SW01,BPV2-AKS01,BPV13 and BPV1 strains,respectively.The results of phylogenetic tree analysis indicated that there was a close relationship between BPV-GZ01 and BPV2-SW01 strains.The prediction of secondary structure of L1 protein indicated that the random coil,extended strand and alphahelix took a higher percentage.The L1 protein was supposed contain 6 potential antigen epitopes.And no transmembrane domains and no signal peptide were found.The tertiary structure of L1 protein was curved spiral structure.These results provided a theoretical basis for immunologic diagnosis and further research of nucleic acid vaccine of BPV. 相似文献
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为缓解南方肉牛夏季生产中的热应激,在牛舍应用冷风机-纤维风管系统,结合两种不同的送风方式(上置置换通风和射流送风)来改善牛舍环境,并比较效果。以栓系饲养西门塔尔杂交牛为试验对象,对牛舍环境、肉牛生理指标进行测量分析。结果表明:测定期间,与舍外相比,上置置换通风舍和射流降温舍温度降幅分别为2.8℃和2.4℃,相对湿度分别升高13.9%和11.9%,两舍之间温湿度均无显著差异(P0.05);射流送风舍0.7m及1.4m风速较上置置换通风舍分别高0.19和0.26m/s(P0.01);射流送风舍试验牛体感温度比上置置换通风舍低0.9℃(P0.01);氨气浓度低1.67mg/m~3(P0.01);试验期间,头部射流舍试验牛的平均呼吸频率比上置置换通风舍低11次/分(P0.01),皮温低0.5℃(P0.01)。研究表明,在高温高湿的气候条件下,冷风机-风管结合射流送风降温可更好地改善牛舍环境,缓解肉牛的热应激。 相似文献
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A herd of 15 Chinese elephants attracted international attention during their 2021 northward trek, motivating the government to propose establishment of an Asian elephant national park. However, planning is hampered by a lack of genetic information on the remaining populations in China. We collected DNA from 497 dung samples from all 5 populations encompassing the entire range of elephants in China and used mitochondrial and microsatellite markers to investigate their genetic and demographic structure. We identified 237 unique genotypes (153 females, 84 males), representing 81% of the known population. However, the effective population size was small (28, range 25–32). Historic demographic contraction appeared to account for low haplotype diversity (Hd = 0.235), but moderate nucleotide and nuclear diversity (π = 0.6%, He = 0.55) was attributable to post-bottleneck recovery involving recent population expansion plus historical gene exchange with elephants in Myanmar, Lao PDR, and Vietnam. The 5 populations fell into 3 clusters, with Nangunhe elephants differing consistently from the other 4 populations (FST = 0.23); elephants from Mengyang, Simao, and Jiangcheng belonged to a single population (henceforth, MSJ), and differed from the Shangyong population (FST = 0.11). Interpopulation genetic variation reflected isolation by distance and female-biased dispersal. Chinese elephants should be managed as 2 distinct units: Nangunhe and another combining Shangyong and MSJ; their long-term viability will require restoring gene flow between Shangyong and MSJ, and between elephants in China and neighboring countries. Our results have the potential to inform conservation planning for an iconic megafaunal species. 相似文献
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Significant changes have taken place within the contemporary architecture since the 20th century: firstly the architecture turns from "thing" to "nothing",secondly the experience of architecture turns from logic to essence intuition,and thirdly the architecture turns from noun to verb,from which we find in surprise the sparks of the Chinese traditional thought which criticizes all the ready-made,especially the conceptual thought with its happening and generation,and shows a new non-subject-object-dimidiate,non-logical and fundamentally non-metaphysical perspective in theory.This made it possible for us to reconsider and reinterpret the contemporary architecture from a more original new perspective. 相似文献
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水土侵蚀过程分析的小波精细积分法 总被引:1,自引:0,他引:1
将小波配置方法和精细积分方法相结合,提出了一种对水土侵蚀模型进行数值分析的新方法——小波精细积分法。与传统的有限元方法相比,本文方法属于半解析方法,对时间步长不敏感,可有效提高计算效率。数值分析结果表明了该方法的有效性。 相似文献