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91.
Niels Tørring Susan Ball Dave Wright Gaïané Sarkissian Marie Guitton Bruno Darbouret 《Reproductive biology and endocrinology : RB&E》2010,8(1):129
Background
A disintegrin and metalloprotease 12 (ADAM12-S) has previously been reported to be significantly reduced in maternal serum from women with fetal aneuploidy early in the first trimester and to significantly improve the quality of risk assessment for fetal trisomy 21 in prenatal screening. The aim of this study was to determine whether ADAM12-S is a useful serum marker for fetal trisomy 21 using the mixture model. 相似文献92.
Possible mitochondrial involvement in mechanism of cytoplasmic male sterility in maize (Zea mays L.) 总被引:1,自引:0,他引:1
The mechanism of cytoplasmic male sterility was investigated in maize by isolating mitochondria from seedlings and various anther stages and analyzing cytochrome oxidase and succinic dehydrogenase biochemically and electrophoretically. Sterile anthers exhibited a lack of biochemical activity and fewer isozymatic bands for cytochrome oxidase. No apparent differences were detected biochemically or electrophoretically between fertile and sterile anthers for succinate dehydrogenase. 相似文献
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Understanding the landscape factors governing population connectivity in riverine ecosystems represents an ongoing challenge for freshwater biologists. We used DNA sequence analysis to test the hypothesis that major geomorphological features underpin freshwater-limited fish diversity in a tectonically dynamic region of New Zealand. Phylogeographic analysis of 101 Galaxias depressiceps cytochrome b sequences, incorporating 55 localities from southern New Zealand, revealed 26 haplotypes, with only one shared among rivers. We detect strong hierarchical genetic differentiation both among and within river systems. Genetic structuring is particularly pronounced across the Taieri River system (63 individuals from 35 sites, 18 haplotypes), with 92% of variation partitioned among locations. Distinctive within-river genetic clusters are invariably associated with major subcatchment units, typically isolated by substantial gorges. The anomalous distribution of a single lineage across a major drainage divide is consistent with local, tectonically driven headwater capture. We conclude that major landscape features such as gorges can strongly partition riverine fish diversity and constrain freshwater biodiversity. 相似文献
95.
Brown JW Echeverria M Qu LH Lowe TM Bachellerie JP Hüttenhofer A Kastenmayer JP Green PJ Shaw P Marshall DF 《Nucleic acids research》2003,31(1):432-435
The Plant snoRNA database (http://www.scri.sari.ac.uk/plant_snoRNA/) provides information on small nucleolar RNAs from Arabidopsis and eighteen other plant species. Information includes sequences, expression data, methylation and pseudouridylation target modification sites, initial gene organization (polycistronic, single gene and intronic) and the number of gene variants. The Arabidopsis information is divided into box C/D and box H/ACA snoRNAs, and within each of these groups, by target sites in rRNA, snRNA or unknown. Alignments of orthologous genes and gene variants from different plant species are available for many snoRNA genes. Plant snoRNA genes have been given a standard nomenclature, designed wherever possible, to provide a consistent identity with yeast and human orthologues. 相似文献
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97.
Dave Siak-Wei Ow Denis Yong-Xiang Lim Peter Morin Nissom Andrea Camattari Victor Vai-Tak Wong 《Microbial cell factories》2010,9(1):22
Background
The overexpression of scFv antibody fragments in the periplasmic space of Escherichia coli frequently results in extensive protein misfolding and loss of cell viability. Although protein folding factors such as Skp and FkpA are often exploited to restore the solubility and functionality of recombinant protein products, their exact impact on cellular metabolism during periplasmic antibody fragment expression is not clearly understood. In this study, we expressed the scFvD1.3 antibody fragment in E. coli BL21 and evaluated the overall physiological and global gene expression changes upon Skp or FkpA co-expression. 相似文献98.
Allen JV Bardelle C Blades K Buttar D Chapman L Colclough N Dossetter AG Garner AP Girdwood A Lambert C Leach AG Law B Major J Plant H Slater AM 《Bioorganic & medicinal chemistry letters》2011,21(18):5224-5229
A directed screen of a relatively small number of compounds, selected for kinase ATP pocket binding potential, yielded a novel series of hit compounds (1). Hit explosion on two binding residues identified compounds 27 and 43 as the best leads for an optimization program having reduced secondary metabolism, as measured by in vitro rat hepatocytes incubation, leading to oral bio-availability. Structure-activity relationships and molecular modeling have suggested a binding mode for the most potent inhibitor 12. 相似文献
99.
Systems genetics reveals a transcriptional network associated with susceptibility in the maize–grey leaf spot pathosystem 下载免费PDF全文
100.