索科线虫RAPD反应条件优化

以中华卵索线虫为材料,研究索科线虫DNA的提取以及对RAPD的影响因素,包括模板DNA、Mg2+、dNTP、引物和Taq聚合酶浓度等,探索最佳反应条件,构建了适于索科线虫RAPD分析的稳定的反应体系.25μL反应体系中,含模板DNA20~40 ng,10×PCR缓冲液2.5μL,MgCl22.0 mmol/L,dNTP 150μmol/L,引物0.3μmol/L,Taq聚合酶1U.实验证明,在对索科线虫进行RAPD分析时,采用优化的反应条件,规范实验操作,使用同厂家同批次的试剂,实验结果就会具有很好的重复性和稳定性.     

两种荒漠小灌木RAPD反应条件优化与引物筛选

分析了模板DNA、引物、Taq酶、dNTP、Mg2+浓度对红砂和长叶红砂RAPD扩增的影响,筛选并建立了适合红砂和长叶红砂的RAPD扩增反应体系:反应体积25μL,内含20 ng模板DNA,0.16μmol/L引物,0.5 U Taq DNA聚合酶,2.5 mmol/L MgCl2,0.1 mmol/L dNTP,2μL10×buffer.用60个引物进行扩增,筛选出扩增效果好的18个引物,为进一步研究红砂和长叶红砂的遗传多样性奠定了基础.     

五条蚋ISSR-PCR反应体系的建立与优化

通过正交试验及单因素试验对五条蝻S.quinquestriatum ISSR-PCR反应体系中的引物、DNA模板、dNTP、Mg2+、BSA、Taq DNA聚合酶浓度6个关键因素进行优化,建立五条蚋ISSR最适反应体系:20μl反应体系中引物1.0 μmol/L、DNA模板50.0 ng/μl、dNTP 0.15 mmol/L、Mg2+ 1.50 mmol/L、BSA 2.00 mg/ml、Taq DNA聚合酶0.155U/μl.通过对24条备选引物进行温度梯度筛选,获得8条能够稳定扩增且多态性较好的引物.为今后利用ISSR技术进行五条蚋种群遗传多样性研究奠定了良好的技术基础.     

濒危植物刺桫椤RAPD反应体系的优化

以高盐SDS法提取濒危植物刺桫椤(Alsophila spinulosa)嫩叶总DNA，进行RAPD分析，分别研究了模板DNA、引物、dNTP、Mg^2 和Taq DNA聚合酶用量以及反应体积对反应结果的影响．筛选并建立了适合于利桫椤RAPD扩增的反应体系：反应体积10μL，内含2ng/μL模板DNA，2．0mmo1/L MgCl2,0．3μmo1／L引物，300μmo1／L dNTP，0．5u Taq DNA聚合酶．     

应用RAPD技术构建绞股蓝DNA指纹图谱

以不同类型绞股蓝(Gynostemma Pentaphyllum,(Thunb)Makino)DNA为模板,进行RAPD反应条件的优化及RAPD结果分析.最终筛选的RAPD反应条件为:20μL PCR反应体系中包括了10×buffer2.0μL,Mg2 2.0 mmol/L,dNTP 0.2 mmol/L,引物0.5 mmol/L,Taq酶1U,模板DNA 50 ng.反应程序为94℃3 min→(94℃30 s→38℃40 s→72℃1 min)45个循环→72℃10min→4℃保持,并从66条随机引物中筛选出5条带型丰富、适合于绞股蓝分析的随机引物.以这5条随机引物对不同类型绞股蓝进行RAPD扩增,识别其特征性多态位点,建立分子标记检索表.     

龙眼基因组DNA提取及RAPD反应体系优化的研究

采用改良CTAB法提取龙眼幼叶基因组DNA,并以其为模板对影响RAPD扩增反应的主要因子采用单因素递进分析方法进行优化,建立了龙眼基因组DNA最佳RAPD反应体系,即在25μL的反应体积中,含20 ng模板, 1．0 U Taq DNA聚合酶,2．0 mmol／L MgCl2,各0．20 mmol／L dNTP,0．20μmol／L引物．     

海桐ISSR-PCR反应体系的建立与优化

利用ISSR技术对海桐的遗传多样性进行研究,对影响PCR扩增效果的一些因素诸如退火温度、Mg2 浓度、4×dNTP浓度、牛血清白蛋白浓度、模板DNA用量、引物用量以及Taq DNA聚合酶用量等指标进行优化,建立了可用于海桐ISSR分析最适宜的反应体系:10μL PCR反应体积中,1×Taq酶配套缓冲液(10mmol/L Tris.HCl,pH值9.0,50 mmol/L KCl,0.1%Triton X-100),2.5 mmol/L MgCl2,0.2 mmol/L 4×dNTP,2.0 mg/mL牛血清白蛋白,10 ng模板DNA,6 pmol引物,0.3 U Taq DNA聚合酶.引物UBC807的最适退火温度为50.7℃.     

铁皮石斛野生居群研究(Ⅳ):RAPD反应体系的构建与优化

为获得铁皮石斛RAPD的最佳反应体系,本文对影响RAPD反应的模板含量、Mg2+浓度、dNTP浓度、Taq酶浓度、扩增程序及退火温度等多种因子进行了构建与优化.通过各因子的组合研究,我们得到铁皮石斛RAPD反应最适扩增体系是:25μLPCR反应体积,10×Buffer 2.5μL,2.5 mmol/L MgC l2,dNTP 2.5μL(各2.5mmol/L),模板DNA为30 ng,Taq聚合酶1.5 U,随机引物12 pmol,ddH2O 14.2μL.最佳扩增程序:94℃预变性3m in,94℃变性50 s,38℃复性1 m in,72℃延伸2 m in,循环40次;最后72℃延伸5 m in.4℃保存.     

柳树RAPD反应体系均匀设计试验研究

从柳树幼苗的嫩叶中提取基因组DNA作为模板,运用均匀设计方法,获得;柳树RAPD扩增反应的优化体系：25μL反应体系中,DNA模板用量70 ng,引物浓度0.5mmol.L-1,Mg2＋浓度3mmol.L-1,TaqDNA聚合酶用量1.0 U,dNTP浓度0.3mmol.L-1.用16条引物进行验证,证实该体系重复性好、结果稳定.     

用正交设计优化甜菜RAPD反应体系

采用正交设计对甜菜的RAPD反应体系进行优化．应用L25（5^6）正交表,研究了Taq、Mg^2＋、随机引物、dNTPs和DNA模板5种RAPD反应组分浓度变化对扩增结果的影响,并进行量化分析,试验结果表明用这种方法建立的甜菜RAPD-PCR优化反应体系为：25μL反应体系中含1×Buffer、1．0mmol／L Mg^2＋、1U TaqDNA聚合酶、0．25mmol／L dNTPs、0．4μmol／L随机引物及25ng DNA模板．     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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