马铃薯卷叶病毒中国株(PLRV-Ch)ORF2a基因5''''端的克隆和序列分析

用设计合成的一对特异性引物，以马铃薯卷叶病毒中国株PLRV—Ch的RNA为模板，经反转录PCR扩增，将获得ORF2a的5′端0．6kb cDNA克隆于pUC19中，构建成重组质粒pLR8．PCR检测和酶切检测表明，获得了ORF2a的5′端0．6kb cDNA克隆，从该cDNA两端进行了两次序列分析，并将获得的核苷酸序列与国外报道的4个PLRV分离株的相应区域的同源性进行了比较，5个序列间具高度同源性。     

鲫血清转铁蛋白cDNA克隆及其序列分析

从GenBank数据库查询发表的鱼类转铁蛋白cDNA或基因序列，根据铁离子结合转运功能位点，设计并合成了两对引物P1、P4以及P2、P3，克隆出鲫血清转铁蛋白cDNA中的核心片段，长度为866bp。再根据克隆出的核心片段分别设计上游及下游两对引物P5、P6以及P7、P8，随后用RACE方法分别克隆出鲫血清转铁蛋白cDNA的5’端(787bp)和3’端(1081bp)以及全长cDNA，最后用计算机程序排列出鲫血清转铁蛋白全长cDNA，长度为2444bp。比较了12种鱼类血清转铁蛋白cDNA序列的同源性。     

鲫血清转铁蛋白cDNA克隆及其序列分析

从GenBank数据库查询发表的鱼类转铁蛋白cDNA或基因序列,根据铁离子结合转运功能位点,设计并合成了两对引物P1、P4以及P2、P3,克隆出鲫血清转铁蛋白cDNA中的核心片段,长度为866 bp.再根据克隆出的核心片段分别设计上游及下游两对引物P5、P6以及P7、P8,随后用RACE方法分别克隆出鲫血清转铁蛋白cDNA的5'端(787 bp)和3'端(1 081 bp)以及全长cDNA,最后用计算机程序排列出鲫血清转铁蛋白全长cDNA,长度为2 444 bp.比较了12种鱼类血清转铁蛋白cDNA序列的同源性.     

马铃薯卷叶病毒中国株(PLRV-Ch)ORF2a基因5′端的克隆和序列分析

用设计合成的一对特异性引物,以马铃薯卷叶病毒中国株PLRV-Ch的RNA为模板,经反转录PCR扩增,将获得ORF2a的5′端0.6kbcDNA克隆于pUC19中,构建成重组质粒pLR8.PCR检测和酶切检测表明,获得了ORF2a的5′端0.6kbcDNA克隆,从该cDNA两端进行了两次序列分析,并将获得的核苷酸序列与国外报道的4个PLRV分离株的相应区域的同源性进行了比较,5个序列间具高度同源性.     

用mRNA差异显示技术分离盐胁迫下小麦耐盐相关cDNA

目的用mRNA差异显示技术分离小麦盐胁迫应答cDNA,为进一步研究小麦耐盐机理奠定基础。方法将小麦(Triticum aesticum L.)耐盐品系宝丰7228r种子分别置于含NaC l 0‰和12‰的Hoagland培养液中生长,7d后分别取叶片,提取总RNA并分离出其中的mRNA,通过锚锭引物O ligo dT10GC反转录和9个10核苷酸随机引物进行PCR扩增。结果DDRT-PCR结果显示,有4个差异DNA片段只在盐胁迫的小麦耐盐品系基因组中表达,而在对照中没有出现。这4个差异cDNA片段分别命名为ts01(260 bp),ts02(330 bp),ts03(420 bp),ts04(600 bp)。4个差异cD-NA片段的RNA杂交结果显示,只有ts04存在明显差异,在盐胁迫条件下有杂交斑点而在对照中没有杂交斑点,其余3个cDNA片段在盐胁迫和对照中都没有杂交斑点。进一步将ts04克隆并进行DNA序列测定及同源性分析。结论ts04可能是耐盐相关cDNA片段,该片段核酸序列与麦属抗性相关的肌动蛋白基因有23%同源。     

马铃薯‘转心乌’F3′5′H的cDNA克隆、原核表达和生物信息学分析

花色苷合成途径中,类黄酮-3'5'-羟基化酶是合成-3'5'-羟基花色素苷的关键酶。从‘转心乌’块茎嫩芽提取总RNA,通过RT-PCR克隆到F3'5'H的cDNA序列(GenBank登录号为HQ860267),SDS-PAGE获得表达蛋白的分子量约为55 k Da。该基因全长1 518 bp,编码区长1 485 bp,共编码494个氨基酸。     

广西巴马小型猪活化素β_A/β_B基因cDNA克隆与序列分析

目的通过克隆广西巴马小型猪活化素(activin)βA/βB基因cDNA,分析其序列,为研究活化素的生物学功能打下基础。方法提取广西巴马小型猪发情母猪的卵巢总RNA,并以其为模板,以下游特异性引物为反转录引物,在AMV酶作用下合成cDNA;用LA-Taq进行PCR扩增出包括成熟肽在内的activinβA及βB基因的部分序列,把两个序列分别连接到PMD-18载体进行克隆和序列分析。结果包括成熟肽在内的activinβA及βB基因的部分序列长度分别为964 bp和791 bp,两个亚基的序列比较保守,与GenBank上发表的猪activin两个亚基同源性达到99.79%和99.62%。activinβA基因有两个碱基发生突变,其中一个在成熟肽序列上,一个在非编码序列上;βB基因信号肽序列上有三个碱基发生突变,其中一个是同义突变。     

小麦泛素融合降解蛋白基因全长cDNA的克隆及分析

实验利用RT-PCR技术，在小麦矮苏3品种中克隆了1个编码泛素融合降解蛋白基因的cDNA，并且含有完整的5′端，将该基因命名为Tufd1，利用RACE技术克隆了该cDNA的3′端。根据这2段cDNA克隆，设计特异引物，利用RT-PCR扩增出了Tufd1完整的开放读码框(ORF)，其编码区长948bp，编码315个氨基酸的多肽，在NCBI中运行BLAST。分析表明，Tufd1蛋白同拟南芥的UFD1蛋白有74％的同源性，在所编码的多肽链的N-端有UFD1保守结构域，可作为催化蛋白降解的信号。     

一种快捷有效的构建cDNA文库的方法

构建cDNA文库是研究基因组功能基因一种有效的手段，传统的建库方法通常需要在双链cDNA两端分别加上带限制性酶切位点的接头序列，通过酶切使之产生与质粒匹配的粘性末端，然后与质粒连接构成文库。本文介绍一种简单而且不需要核酸内切酶的构建cDNA文库的方法。该方法的主要步骤包括：（1）通过反转录合成cDNA第一条链，通过置换底物的方式在cDNA3’末端合成接头序列。（2）利用cDNA两端的接头引物，通过TaqDNA合成酶PER扩增合成cDNA第二条链。（3）将PCR产生的双链cDNA直接与T-载体连接。（4）将连接物转化大肠杆菌，得到cDNA文库。利用本方法，我们成功构建红树植物红海榄的cDNA文库。PCR结果显示插入的片段分布在O．5～3．0kb之间，大部分cDNA的长度在500—1000bp之间，表明cDNA具有较好的完整性。本方法具有操作简单、高效率、低成本、RNA模板需要量少的特点，而且适用于任何高等生物RNA样品。     

玉米双孔通道(TPC1)基因片段的克隆与分析

为克隆玉米TPC1基因,根据几个物种已知的TPC1基因保守区域设计一对简并引物,以玉米RNA反转录生成的cDNA为模板进行Touchdown PCR扩增,得到1条695 bp的特异性条带,测序后与其他物种的TPC1基因进行比对,该片段与水稻OsTPC1、小麦TaTPC1、大麦HvTPC1、拟南芥AtTPC1、烟草NtTPC1A和NtTPC1B基因的同源性分别为88.1%、84.4%、84.7%、60.6%、61.1%、60.8%.基因片段推测的氨基酸序列包括5个跨膜片段(TMS)和1个孔道(P)的部分区域,第4个跨膜片段富含带正电的氨基酸残基,可能作为TPC1的电压传感器(Voltage sensor).这种结构与电压门控Na /Ca2 离子通道的第4个跨膜片段的结构和性质相似,提示含有这个片段的蛋白可能是被电压调控的.在玉米的dbEST中没有与该基因片段相似的序列,我们把它命名为ZmTPC1.     

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.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

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     

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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