MicroRNA特征与功能

通过分析总结现代分子生物学国际前沿microRNA(miRNA)领域的研究文献，整理出miRNA研究的基本脉络和走向。miRNA是一类长度～22nt的非编码小分子RNA，在包括线虫、果绳、家鼠、人体以及拟南芥等生物中普遍存在；它在调节基因转录与表达，调控生物体正常发育等生理过程中扮演重要角色。从比较的角度出发，揭示了miRNA与小干扰RNA在其代谢与功能方面共用某些途径，相互交叉与替代，可能同属一个更广范围的小分子RNA介导的生理调控机制。miRNA的研究可能对新一代基因药物的开发具有深远意义。     

MicroRNA的生物合成及作用机制

MicroRNA(miRNA)是真核生物中一类长度约为22个核苷酸的非编码小分子RNA。它们能够通过与靶mRNA特异性结合引起靶mRNA的降解或者抑制其翻译而在动植物基因表达调控中扮演重要角色。本文主要就miRNA的生物学特征、生物合成、作用机理及其功能等方面进行综述。     

MiRdetector：一个预测与搜寻miRNA基因的计算工具

MicroRNA（miRNA）是一类内源性的长约21～24 nucleotide(nt)的非编码小分子RNA,能够调节其它基因的表达活性,在生物体的发育过程中发挥重要的作用.每种生物体中miRNA的基因总数还未知,生物信息学分析手段为发现新的miRNA基因提供了有效的方法.作者开发了一个预测与搜寻miRNA基因的完全自动化系统“MiRdetector”.MiRdetector系统是基于计算机比对和miRNA前体茎环结构判断的.用水稻miRNA基因对系统的预测精度进行了检验,系统正确识别了155个样本中的140个,预测精度达到90.32％,并且搜寻到了95个可能的水稻miRNA基因.由于系统的假阳性率较低,因此能够为进一步证实miRNA基因的实验研究提供高质量的数据集.     

microRNA与宫颈癌关系的研究

MicroRNA（miRNA,微小RNA）是一大家族小分子非编码单链RNA,长约19~25个碱基。最新研究表明miRNA可参与多种调节途径,包括细胞增殖凋亡、细胞分化、生殖以及肿瘤发病机制等。实验证据表明,miRNA可通过调控其靶基因参与的多种信号通路,影响宫颈癌的发生发展,为宫颈癌发病机制的研究和诊断治疗提供了新的思路。本文就近年来miRNA与宫颈癌发生发展、诊断治疗的相关研究进展作一综述。     

微RNA在非小细胞肺癌中的研究进展

微RNA(miRNA)是一类内源性、非编码的单链小分子RNA,作用广泛,参与生命活动中的一系列重要进程,并与肿瘤的发生、发展密切相关。大量研究表明,微RNA参与肺癌的发生、发展和预后,具有与原癌基因或肿瘤抑制基因相似的作用。在肺癌组织中微RNA有特定的表达谱,参与调节肿瘤血管生成等多个过程,并可作为生物标志物用以早期诊断,靶向治疗及临床预后。作为一类新的分子靶标,微RNA为肺癌的诊断和治疗提供了新的方向。     

miRNA传感检测技术的研究进展

微小RNA（miRNA）是一类新发现的长度为21-25个核苷酸的RNA,它在转录后水平调节靶基因表达．已有研究表明,miRNA在发育、细胞增殖、凋亡、脂类代谢、激素分泌及肿瘤发生等多种生理和病理过程中发挥重要作用．针对miRNA的检测技术的研究主要包括2大类：一是以传统实验技术方法为基础建立起来miRNA特有的技术方法,二是已成熟应用的生物传感技术．综述了2大类miRNA的检测技术,并对现有的检测技术的特点进行分析．     

MicroRNA在白血病中的研究新进展

微小RNA(microRNA,miRNA)是在真核生物中发现的一类内源性非编码RNA,其长度为21 ～ 25个核苷酸大小.miRNA在基因表达调控中发挥了重要作用.miRNA不仅在白血病中存在明显的表达失调,而且与白血病的诊断和预后有关.本文着重综述了白血病中急性髓系白血病(AML),急性淋巴细胞性白血病(ALL)和慢...     

Sigma因子6促进拟南芥MIRNA基因转录

本研究在筛选拟南芥miRNA水平异常的突变体的过程中,分离得到了一个新的突变体m112,随后通过图位克隆结合基因组测序发现M112的突变基因编码Sigma因子6(SIG6).通过Northern blot和小分子RNA测序,明确了sig6突变体中成熟miRNA的累积下调;通过荧光定量PCR检测pri-miRNA的表达,发现sig6突变体中pri-miRNA水平下调;进一步的MIRNA基因的启动子融合报告基因GUS染色结果显示在sig6突变体中,MIRNA基因启动子的活性减弱.这些实验结果表明SIG6通过影响MIRNA基因的转录参与了miRNA的生物合成,为人们进一步了解miRNA的生物合成途径提供了帮助.     

子痫前期患者胎盘组织中miR-411表达的研究

研究miR-411在子痫前期患者和正常产妇胎盘组织中的表达差异,探讨微小RNA(miRNA)对子痫发病所起到的作用,收集子痫前期患者胎盘组织和正常产妇胎盘组织,并从中提取RNA;采用miRNA特异RT引物进行反转录; 最后用荧光实时定量PCR(Real Time PCR)的方法检测基因的表达量.结果 miR-411在子痫前期患者胎盘组织中表达降低.表明此次实验阐明了子痫前期患者胎盘组织中存在特异miRNA的差异表达,子痫前期发病可能受到miRNA的调控.     

在微RNA研究中,“沉默”是金

微RNA(miRNA)是非编码单链RNA的小片段,通过调节基因的表达,在许多生物学进程中扮演重要角色。已经发现了5000多种不同的miRNA,Wellcome Trust Sanger研究所发布的最新目录列举了5395个(见http://     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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