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231.
提出一种推广一次二阶矩法的算法,解决了关于相关正态随机向量的非线性极限状态方程下结构可靠度计算问题,在理论上论证了方法的可行性,实例计算表明了方法的有效性。 相似文献
232.
采用举例的方式阐述了CNMARC中各相关字段的对应著录,以使编目数据更加标准和规范,实现编目数据的共享。 相似文献
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为建立芝麻抗旱性快速鉴定体系及筛选芝麻抗旱品种,采用盆栽反复干旱法,设置正常水分(CK)和干旱胁迫(DS)两种处理,对31份芝麻材料进行生理生化指标测定和综合评价,同时利用qRT-PCR检测SOD合成相关基因的表达量。结果表明:芝麻苗期O2、可溶性糖(SS)、脯氨酸(Pro)含量和超氧化物歧化酶(SOD)、过氧化物酶(POD)活性与CK相比均显著上升,各指标综合抗旱系数和抗旱指数的变异系数最高的分别是SOD(98.64%)和O2(154.01%);抗旱指数与O2含量、SOD活性呈极显著正相关关系,这两个指标可作为芝麻苗期抗旱性鉴定的重要指标。聚类分析将31份芝麻材料划分为5类抗旱类型,分别为高抗型、中抗型、低抗型、低感型和高感型。利用综合评价方法,筛选出高抗材料2份(‘汾芝10号’和‘豫-11-1’),中抗旱材料4份,低抗旱材料9份,敏感材料10份,高感材料5份;筛选出O2含量和SOD活性可作为芝麻种质资源苗期抗旱特性快速鉴定的指标。 相似文献
237.
The purpose of this experiment was to study the correlation between exon 1 and 4 polymorphisms of DRB1 gene and brucellosis in Kazakh sheep.Using RBPT serological tests to try sheep serum,reference in GenBank sheep MHC Class Ⅱ area DRB1 gene sequences (Accession No.:NC_040271.1),the exon 1 and 4 pieces designed primers,using PCR-SSCP and DNA sequencing technology to 230 Kazak sheep DRB1 gene polymorphism detection,analyze its polymorphism loci and the relationship between the Kazak sheep Brucella susceptibility.The results showed that 66 Kazakh sheep were positive for Brucella in RBPT test,and the positive detection rate was 28.7%.There was one SNP locus (F1-G22A) in exon 1 fragment,and sequencing determined two genotypes (GG and GA),the dominant allele and genotype were G and GG respectively,and the susceptibility genotype of the polymorphisms of F1-G22A was GA.Chi-square test showed that there was no significant correlation between the polymorphisms of DRB1 gene F1-G22A and Brucella susceptibility in Kazakh sheep (P>0.05).According to the analysis of bioinformatics online software,the F1-G22A polymorphic sites lead to the change of RNA secondary structure and the decrease of minimum free energy,and lead to the change of protein secondary structure.No SNPs were found in DRB1 exon 4 fragment.Therefore,there might be a certain correlation between the polymorphisms of DRB1 gene F1-G22A and Brucella susceptibility in Kazakh sheep. 相似文献
238.
ABSTRACT: The nucleotide sequences of Japanese flounder Paralichthys olivaceus , major histocompatibility complex (MHC) cDNA, classical MHC class Iα, non-classical MHC class Iβ, MHC class IIα and IIβ, were determined. The domain structures and antigen binding motifs of vertebrate MHC are conserved in the Japanese flounder MHC. A phylogenetic analysis supports the classification of these genes into class I and class II MHC. Classical MHC class Iα was ubiquitously expressed, whereas the non-classical MHC class Iβ was expressed mainly in lymphoid organs, gills, intestine and stomach. The MHC classes IIα and IIβ were also ubiquitously expressed. 相似文献
239.
DING Xuedong WANG Guohua PAN Xiangchen LIU Dongdong LUO Xuedong MA Yuan LI Maolin CUI Qi ZHANG Qijin 《中国畜牧兽医》2007,47(12):3815-3824
The purpose of this study was to investigate the variation of Orf virus (ORFV) immune related genes after infection with different species.The ORFV genomes of sheep and camel were extracted and named ORFV-Y and ORFV-LT,respectively.Based on ORFV genome sequence published in GenBank (accession No.:KF234407.1),three pairs of specific primers were designed and synthesized to amplify the B2L,F1L and VIR gene fragments of ORFV-Y and ORFV-LT,respectively,and the amplified fragments were cloned into pMD19-T vector,transformed into E.coli DH5α competent cells.The recombinant plasmid was identified,and positive clones were selected for sequencing,DNAStar software was used to analyze the homology,amino acid sequence and phylogenetic tree of 13 ORFV genome sequences published on NCBI.The results showed that the nucleotide homology of B2L,F1L and VIR genes were 92.8% to 99.2%,95.7% to 99.5% and 77.6% to 100%,respectively.After comparing the amino acid sequence between the two genomes and the reference sequence,it was found that there were obvious differences in the immune related genes between the two genomes,and F1L gene had some rules to follow.The phylogenetic analysis of B2L,F1L and VIR genes showed that ORFV-Y was closely related to the Chinese Fujian goat strain,while ORFV-LT was far from the reference strains,and was a separate branch.The results showed that ORFV had obvious difference in immune related genes between sheep and camels,it provided a reference basis for further research on the changes of ORFV gene sequences in different species and the development of vaccines for different species in the future. 相似文献
240.
分蘖与株高是禾本科草类植物重要的农艺性状,明确参与调控分蘖与株高的基因类型对牧草和草坪草分子辅助育种具有重要意义。以表型差异明显的两个高羊茅品种“Kentucky-31”(K31)和“Regenerate”为材料,旨在构建高羊茅分蘖节转录组图谱,挖掘在分蘖节部位调控生长发育相关的差异表达基因(differentially expressed genes,DEGs)。基于高通量测序技术平台Illumina HiSeq 2500×Miseq 300进行转录组测序,并将得到的数据进行de novo组装,结果共获得77872条单基因簇(unigene)。将获得的unigenes与非冗余蛋白数据库(non-redundant protein database,NR)、蛋白质数据库(universal protein,Uniprot)、基因本体数据库(gene ontology,GO)、东京基因与基因组数据库(kyoto encyclopedia of genes and genomes,KEGG)以及直系同源蛋白簇(clusters of orthologous groups,COG)数据库进行比对,结果显示:分别有59927、40213、44447、15146和13767条unigenes成功获得注释。“Regenerate”与“K31”对比有1573个上调DEGs和1441个下调DEGs。GO富集分析发现,DEGs主要富集在细胞、细胞组分、大分子复合物组装等生物过程。DEGs中共注释到42个差异表达转录因子,主要包括TCP、WRKY和ARF等19种类型。还注释到与8类植物激素相关的DEGs,包括生长素、细胞分裂素、脱落酸、赤霉素、乙烯、油菜素甾醇、水杨酸和茉莉酸。利用实时荧光定量PCR对DEGs进行表达模式验证,发现其与RNA-Seq测序结果一致,证实了测序结果的准确性。研究结果丰富了高羊茅的转录组序列资源,初步获得控制株高及分蘖发育的候选因子,为进一步开展基因功能及分子育种研究提供了理论支持。 相似文献