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Ye. P. Dulepova V. A. Nadtochii L. L. Budnikova 《Russian Journal of Marine Biology》2008,34(7):472-481
The trophic structure of benthic communities in the Sea of Okhotsk and Bering Sea was analyzed based on the results of macrobenthic
survey catches conducted in the Far Eastern seas in the 2000s. The production of trophic levels and entire communities was
determined. It was shown that production of benthic communities is still at a high level and has almost not changed since
the 1980s. The arrangement of the communities of some shelf areas by productivity characteristics was made. 相似文献
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Weilan Ye 《The EMBO journal》2014,33(8):786-787
Since metastatic lesions of solid tumors are the major cause of mortality in cancer patients, understanding the molecular mechanisms of metastasis is of paramount importance. Although extensive knowledge has been accumulated regarding the early steps in metastasis—starting with the departure of cancer cells from their primary sites, to their transit through the hematogenous and/or lymphatic systems, and ending with their entrance into the parenchyma of distant organs—it is difficult if not impossible to translate such knowledge into medicine due to the challenge of identifying patients with only primary tumors but otherwise pristine organs. In other words, autopsy studies indicate that a large proportion of patients already harbor dormant, undetectable micrometastases at the time of cancer diagnosis (Hensel et al, 2013 ). Accordingly, stopping tumor cell dissemination is too late for these patients. Therefore, understanding the survival and outgrowth of micrometastases may hold greater promise to combat metastatic disease. 相似文献
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Miguel Angel Pujana Monica Gratacós Jordi Corral Isabel Banchs Aurora Sánchez David Genís Carlos Cervera Víctor Volpini X. Estivill 《Human genetics》1997,101(1):18-21
Genetic anticipation – increasing severity and a decrease in the age of onset with successive generations of a pedigree –
is clearly present in autosomal dominant cerebellar ataxia (ADCA). Anticipation is correlated with expansion of the CAG/CTG
repeat sequence to sizes above those in the normal range through the generations of a pedigree. Genetic heterogeneity has
been demonstrated for ADCA, with four cloned genes (SCA1, SCA2, SCA3/MJD, and SCA6) and three mapped loci (SCA4, SCA5 and
SCA7). Another related dominant ataxia, dentatorubral-pallidoluysian atrophy (DRPLA), presents anticipation with CAG/CTG repeat
expansions. We had previously analysed ADCA patients who had not shown repeat expansions in cloned genes for CAG/CTG repeat
expansions by the repeat expansion detection method (RED) and had detected expansions of between 48 and 88 units in 17 unrelated
familial cases. We present here an analysis of 13 genes and expressed sequence tags (ESTs) containing 10 or more CAG/ CTG
repeat sequences selected from public databases in the 17 unrelated ADCA patients. Of the 13 selected genes and ESTs, 9 were
found to be polymorphic with heterozygosities ranging between 0.09 and 0.80 and 2 to 17 alleles. In ADCA patients none of
the loci showed expansions above the normal range of the CAG/CTG repeat sequences, excluding them as the mutation causing
ADCA.
Received: 28 May 1997 / Accepted: 30 June 1997 相似文献
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贝壳历来是生物工程和材料学研究的重要对象。贝壳中的贝壳基质蛋白质在贝壳的形成与发育过程中具有重要的调控作用。Whirlin类蛋白质(Whirlin-like protein,WLP)是一种从厚壳贻贝(Mytilus coruscus)中鉴定的新型贝壳基质蛋白质。序列分析结果显示,该蛋白质含有PDZ(postsynaptic density/Discs large/Zonula occludens)结构域,而该结构域对贝壳生物矿化的影响目前尚无报道。为深入了解WLP在贝壳形成中对碳酸钙晶体的影响,在序列分析基础上,采用密码子优化结合原核重组表达,获得其重组表达产物后,开展了重组WLP对碳酸钙晶体形貌及晶型的影响研究,结晶速度抑制以及碳酸钙晶体结合分析。分析结果表明,重组WLP能诱导文石型碳酸钙晶体的形貌和方解石型碳酸钙晶体的晶型发生改变;同时重组WLP对碳酸钙晶体具有结合作用,且能抑制碳酸钙晶体的结晶速度。上述结果表明,WLP对贝壳的形成及发育具有重要影响,并可能在贝壳肌棱柱层的形成中发挥了重要作用。 相似文献
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Yang Su-Rong Sun Huan-Xin Hu Zhen-Zhen Wang Si-Heng Sun Hui Xue Yin-Jia Ye Chen-Bo 《Sleep and biological rhythms》2017,15(1):57-65
Sleep and Biological Rhythms - Chronic sleep deprivation (SD) is an overwhelming problem in young students. Firstly, we investigated whether different levels of pre-training SD had effects on... 相似文献
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