水稻中一个与花发育相关的MADS-box基因的表达检测

根据MADS－box基因的保守区结构，设计简并性引物，利用RT－PCR从水稻（Oryza sativa L.)中克隆到一个新的水稻MADS－box基因cDNA睛段，将它命名为FDRMADS5．该基因核苷酸序列851bp,编码160个氨基酸，有典型的植物MADS－box基因的结构，FDRMADS5的Southern分析，表明它为单拷贝基因，用Northern检测了FDRMADS5的表达情况，发现该基因除了在花中有表达外，在水稻的根尖和幼苗端中也有微量的表达，这一结果表明，水稻的MADS－box基因功能可能并不局限于控制花的发育。     

用抑制差减杂交技术分离烯丙异噻唑诱导水稻特异表达的基因

烯丙异噻唑(PBZ)处理水稻根能使其产生对稻瘟病的系统获得性抗性,因此在东南亚稻区被广泛用于防治稻瘟病,然而关于其作用的分子机理还知之甚少．运用抑制差减杂交技术,试图通过分离鉴定受PBZ诱导调控的关键基因,探索其作用的分子机理．以PBZ处理后的水稻叶片cDNA为目标群体(tester),以未处理水稻叶片cDNA为对照群体(driver),用经过对照cDNA差减的、烯丙异噻唑处理的cDNA群体构建了一个含260个重组子的差减文库．通过差示筛选鉴定出了26个。PBZ诱导水稻特异表达和增强表达的候选克隆．对26个cDNA克隆进行了双向测序和同源性比较,发现其中3个克隆：rJAB1,rTAB2和蛋白磷酸酯酶2Aδ调节亚基同型物基因,位于抗病相关信号转导途径上,它们与哺乳动物和人类免疫途径上的信号因子有明显相似之处,因此推断可能与诱导抗性有关．另外8个克隆与已知基因同源性为70％～99％．经Northern杂交分析,其中rJAB1(编码c-jun激活区结合蛋白1)受烯丙异噻唑和稻瘟菌诱导表达;膜糖蛋白同源基因及肌动蛋白(actin)α1受烯丙异噻唑诱导表达,部分克隆为低丰度转录本．     

水稻中一个与COI1同源的基因克隆及其表达分析

利用同源序列分析,在水稻基因数据库中检索到了几条与拟南芥中的COI1基因具有高度同源性的EST(expression sequence tag)片段和相应的基因组序列．根据EST拼接和基因组比较结果设计引物,利用RT—PCR在水稻中得到与COI1高度同源的cDNA,并在基因组中推断出相应的基因,命名为RCOI1．RCOI1与COI1在氨基酸水平有74％的同源性．与COI1相似,RCOI1蛋白也具有典型的F—box和LRRs结构域．半定量RT—PCR显示该基因的表达受茉莉酸甲酯(MeJA)的诱导,说明这个基因可能参与水稻茉莉酸应答反应．该基因的发现对于探索单子叶植物的茉莉酸信号转导途径,以及研究该途径在农作物中的抗虫抗病和抵抗恶劣环境等方面的作用都有重要意义．     

簇毛麦中谷胱甘肽硫转移酶基因的克隆与表达分析

利用抑制性消减杂交(SSH)方法克隆差异表达片段EST639,从簇毛麦cDNA文库中筛选到一个类谷胱甘肽硫转移酶基因(GST)的全长cDNA,命名为HvGSTF.该序列长1 232 bp,具完整的开放阅读框(ORF),编码一条含229个氨基酸残基的多肽,推导其分子量为25.6 kDa,等电点为4.89.该多肽的氨基酸序列与小麦、水稻、大麦、玉米、拟南芥的类GST分别具有83%,63%,61%,52%和47%的相似性.Northern杂交表明,HvGSTF在抗、感病簇毛麦叶片中都为组成型高表达,但在受白粉菌侵染的抗、感病簇毛麦中的表达模式不同,却与活性氧的积累模式存在着一致性,推测HvGSTF在簇毛麦细胞免受活性氧毒害方面起着重要作用.     

人新的PLP基因全长cDNA的克隆与分析

在批量分离与脑发育相关的基因克隆时,从人3个月胎脑cDNA文库中得到一全长2261bp的cDNA克隆.其开放性阅读框架编码一个含有551个氨基酸残基的蛋白质,此蛋白与一种推测的细胞结构调节蛋白parelemmin同源,故命名为PLP(paralemmin-like protein).GenBank接受号为AF132731.Northern杂交显示该基因只有一个转录本,大小与获得的该克隆吻合.组织表达谱分析发现该基因在成人心脏、骨骼肌中的表达量高于其他组织.     

青岛文昌鱼泛素/52氨基酸融合蛋白AmphiUb52的研究

通过神经胚cDNA文库的大规模测序，从青岛文昌鱼(Brachiostoma belcheri tsingtauense)成功分离到一个泛素cDNA(AmphiUh52)克隆，演绎出的128位氨基酸序列揭示该基因产物为一个融合蛋白(76个氨基酸的泛素和52个氨基酸的60S核糖体蛋白)．序列同源性分析表明该基因在所有的真核生物中都高度保守．在52个氨基酸的核糖体蛋白中可能含有一个“锌指”模式参于核酸的结合．     

芸苔EPSPs基因cDNA的克隆和表达载体的构建

作者从芸苔(Brassica campestris)中用RT-PCR方法获得了EPSPs基因的cDNA．与其他物种中的EPSPs基因进行了比对和分析发现：芸苔EPSPs基因的cDNA与欧洲油菜的同源性最高,为93％,与水稻同源性最低,仅为64％．将芸苔EPSPs的ORF片段插入到GTK融合表达载体中,为EPSPs的原核表达奠定了基础。     

蝴蝶兰查尔酮合酶基因cDNA的克隆、鉴定及其原核表达

利用逆转录．聚合酶链式反应(RT-PCR)得到在蝴蝶兰花瓣中特异性表达的查尔酮合酶cDNA(pchs-1)．DNA序列分析表明,该序列与已发表的查尔酮合酶基因有很高的同源性．将此cDNA序列不改变阅读框架克隆到pET-24α( )原核表达载体上,经IPTG诱导后,SDS-PAGE的结果表明有预测大小的蛋白受诱导表达,该基因在植物中的功能验证工作正在进行中．     

棉花转化酶基因保守片段的克隆及其序列分析

通过CODEHOP designer对已登陆GENEBANK的植物酸性转化酶基因序列的同源性分析,根据植物酸性转化酶基因保守区序列设计简并引物,以棉花总RNA为模板,通过RT-PCR方法得到cDNA,以此为模板通过PCR扩增得到片段长为1155bp的片段,将其克隆到加T载体上,经PCR和酶切鉴定筛选得到阳性克隆,并将阳性克隆进行测序,然后在GENBANK中进行blast检索。结果表明本研究克隆的棉花酸性转化酶基因片段编码的氨基酸与甜橙(BAF34362)、温州蜜桔(BAB82419)和梨(BAF35859)的液泡酸性转化酶基因编码的氨基酸的同源性分别为75%、75%和73%。因此,推测获得的基因片段定位于液泡。     

苜蓿花叶病毒复制酶基因全长cDNA植物表达载体的构建和对烟草的转化

将苜蓿花叶病毒中国分离株(Alfalfa mosaic virus Chinese isolate，A1MV-Ch)的复制酶P2亚基(90 kD蛋白)基因的全长cDNA构建到植物表达载体pROKⅡ中，得到重组植物表达载体pAIMV-FL．用三亲融合法导入农杆菌LBA4404，并转化烟草，经PCR检测，获得了含全长cDNA的转基因烟草植抹．     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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