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Young-of-year largemouth bass from lakes Mead and Mohave fed upon crustacean zooplankton, insects (primarily chironomids), and fish. Largemouth bass smaller than 32 mm TL fed extensively upon zooplankton. In Lake Mead, transition to an insect-dominated diet occurred at 32 mm TL; transition to an insect-fish—dominated diet did not occur in Lake Mohave until a length of 56 mm was reached. Largemouth bass from Lake Mohave consumed significantly more zooplankton than did those from Lake Mead, but largemouth bass from Lake Mead consumed significantly more insects. Fish were most common in the diet of young-of-year largemouth bass larger than 52 mm TL.  相似文献   
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We performed a meta-analysis of five genome-wide association studies to identify common variants influencing colorectal cancer (CRC) risk comprising 8,682 cases and 9,649 controls. Replication analysis was performed in case-control sets totaling 21,096 cases and 19,555 controls. We identified three new CRC risk loci at 6p21 (rs1321311, near CDKN1A; P = 1.14 × 10(-10)), 11q13.4 (rs3824999, intronic to POLD3; P = 3.65 × 10(-10)) and Xp22.2 (rs5934683, near SHROOM2; P = 7.30 × 10(-10)) This brings the number of independent loci associated with CRC risk to 20 and provides further insight into the genetic architecture of inherited susceptibility to CRC.  相似文献   
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IntroductionImprovingthebreedofcotton ,akindofprincipaltextilerawmaterial,withtransgenictechnology ,hasbeenemphasizedforaverylongtime .However,researchanddevelopmentontransgeniccottonallovertheworldaremainlyfocusedondisease resistantandinsect resistantproperties ,whiletheresearchonimprovingthequalityofcottonfiberwithtransgenictechnologyisseldomcarriedout[1] .Nowresearchershaveinoculatedthegeneofanimalkeratinintocottonfiberwithtransgenictechnologyandproducedthekeratintransgeniccotton ,inthehope…  相似文献   
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Russo G 《Nature》2008,452(7187):660-661
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小麦组织培养再生潜力与抗氧化胁迫能力具有相关性。为解析小麦TaCATs基因家族的分子生物学及生化特性并为后续试验验证奠定理论基础,利用e-PCR方法进行小麦过氧化氢酶(CAT)新基因克隆,结合in silico技术对小麦TaCATs基因家族的生化特性进行分析和预测。氨基酸序列同源性比对结果表明,克隆的小麦TaCATs基因家族新成员与水稻的CatA和玉米的Cat3具有较高的相似性,分别达89%及81.1%,命名为TaCAT3,基因组DNA和cDNA长度分别为1986和1482bp,编码494个氨基酸的蛋白。亚细胞定位结果表明,TaCAT3可能定位在线粒体中,且所有的功能活性位点在小麦TaCATs家族中具有一致的保守性。系统发生树构建结果表明,小麦TaCATs能形成3个独立的分支。在蛋白质编码序列同源比对的基础上,利用SwissModel的Swiss-PdbViewer 3.7软件包对TaCATs高级结构进行同源模拟,发现所构建的模型能很好地反映TaCATs的高级结构。  相似文献   
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This paper focuses on a new optimization problem, which is called "The Multiple Container Packing Problem (MCPP)" and proposes a new evolutionary approach for it. The proposed evolutionary approach uses "Adaptive Link Adjustment Evolutionary Algorithm (ALA-EA)" as a basic framework and it incorporates a heuristic local improvement approach into ALA-EA. The first step of the local search algorithm is to raise empty space through the exchange among the packed items and then to improve the fitness value through packing unpacked items into the raised empty space. The second step is to exchange the packed items and the unpacked items one another toward improving the fitness value. The proposed algorithm is compared to the previous evolutionary approaches at the bench-mark instances (with the same container capacity) and the modified benchmark instances (with different container capacity) and that the algorithm is proved to be superior to the previous evolutionary approaches in the solution quality.  相似文献   
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