哺乳动物异种间体细胞核移植技术进展

自1997年绵羊体细胞核移植成功后,克隆技术发展迅速,克隆技术与胚胎干细胞的结合,产生了治疗性克隆的理念.文中对克隆技术的研究进展、方法和意义作了综述,并重点对哺乳类动物异种间核移植的方法技术和伦理学进行讨论.     

克隆技术的最近研究进展

随着克隆技术研究领域取得巨大突破,克隆技术日益受到广泛关注。本文中,讨论了近年来克隆技术研究领域中取得的主要成就,并对其进行了总结。全面综述了动物克隆技术的基本原理,在“Dolly”羊、猕猴胚胎干细胞以及人类胚胎干细胞的克隆中所取得的各项技术突破,面临的问题以及克隆技术的应用价值及发展前景。     

哺乳动物克隆的研究进展

哺乳动物体细胞克隆是20世纪末生命科学领域最引人注目的高新技术,该技术在农业、生物学和医药等方面具有广泛的应用前景。近年来克隆技术发展迅速,多种哺乳动物相继克隆成功,但也存在着克隆效率太低、克隆动物表型正常而实质异常等问题。本文在近年来克隆技术研究的基础上,对克隆的概念、研究历史以及克隆的方法、过程进行了综述,展望了克隆的意义及克隆动物的应用前景,分析了目前克隆技术尚存在的问题,并提出了解决这些问题的关键。     

影响哺乳动物体细胞克隆效率因素的研究进展

动物克隆技术的低效率在很大程度上限制了它的应用.克隆过程的多步骤决定了影响因素的多样性.综述了体细胞核的重编程、供体细胞的选择、受体胞质、活化方法、培养条件等对克隆效率的影响,对这些问题的认识将有利于对克隆机理的研究.     

国外有关克隆技术的法制规定

自 1 997年克隆羊多莉诞生后 ,引起各国政府对克隆技术在人体和科学研究中所出现的问题的重视。近年体细胞克隆技术、核移植技术和胚胎干细胞培育技术已日趋成熟 ,一方面通过动物实验可以解决生命科学上的未知问题 ,尤其是人们期待其在再生医学和再生医疗上发挥作用 ;另一方面各国政府和科研人员也感觉到 ,在克隆动物实验研究和克隆技术应用于人类的实验研究方面其界限尚不清楚。在这种情况下 ,世界各国相继制定了各种法律法规 ,对此项研究进行规制。在 1 997年 5月世界卫生组织 (WHO)的会议上制定了“关于克隆技术的决议” ,明确指出不允…     

哺乳动物克隆的现状和研究进展

 哺乳动物细胞克隆是20世纪末生命科学领域最引人注目的高新技术,该技术对于优良种畜的复制、减少试验用动物数目、动物遗传多样性保存及濒危动物挽救、转基因动物培育等方面具有重要意义。近年来克隆技术发展迅速,多种哺乳动物相继克隆成功,但也存在克隆效率太低、克隆动物表型正常而实质异常的问题。本文详细阐述了克隆效率太低、克隆动物表型正常而实质异常问题,介绍了当前动物克隆技术的发展现状,并对动物克隆涉及的技术进行了总结和概括,着重介绍了卵母细胞的去核方法和重组胚的构建方法。     

哺乳动物克隆技术研究进展

对哺乳动物细胞核移植克隆技术的基本环节作了系统综述,叙述了该研究领域的最新发展。     

动物抑制素的分子生物学特性

抑制素是一种水溶性非类固醇促性腺因子，它选择地抑制促卵泡素的分泌，是控制卵泡生长和精子生成的关键激素之一。近年来，用克隆技术已测出大鼠，牛，绵羊，猪，禽类和人类的抑制素氨基酸序列。本文综述了动物抑制素的来源，合成特性，分子结构，牛卵泡液抑制素Ｎ端氨基酸序列，人类抑制素基因结构，几种动物抑制素亚单位比较和亚单位的表达等方面的研究进展。     

科学家最近指出克隆动物命不长

当人们为克隆动物的出现而欢欣鼓舞,并盼望着克隆技术给人类的生活带来实惠之时,科学家们最近的研究成果无疑给他们浇了一盆冷水。科学家们说,克隆技术缺陷太多,离投入实用还远得很。     

动物抑制素的分子生物学特性(综述)

抑制素是一种水溶性非类固醇促性腺因子，它选择性地抑制促卵泡素的分泌，是控制卵泡生长和精子生成的关键激素之一。近年来，用克隆技术已测出大鼠、牛、绵羊、猪、禽类和人类的抑制素氨基酸序列。本文综述了动物抑制素的来源、合成特性、分子结构、牛卵泡液抑制素Ｎ端氨基酸序列、人类抑制素基因结构、几种动物抑制素亚单位比较和亚单位的表达等方面的研究进展。     

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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