小鼠胚胎干细胞R1表面特异结合多肽的筛选

胚胎干细胞是从哺乳动物胚胎发育早期的囊胚的内细胞团内分离出来的一类细胞,具有自我更新和全能性的基本特征.作者利用M13噬菌体展示技术筛选与未分化的小鼠胚胎干细胞R1表面特异结合的多肽.实验利用未分化的小鼠胚胎干细胞为筛选靶细胞,分化的小鼠胚胎干细胞为吸附细胞,进行3轮的消减筛选,经细胞ELISA鉴定,噬菌体DNA测序和多肽序列分析,得到13条能与小鼠胚胎干细胞特异结合的多肽.通过BLASTP比对发现有11个体内的同源蛋白,为进一步研究小鼠胚胎干细胞表面分子提供研究基础.     

中国科技，日新月异（下）

老鼠“小小”，推动医学进展 “小小”是我国科学家利用iPS细胞（被通俗地称为皮肤干细胞，是由皮肤细胞改造成的几乎可与胚胎干细胞相媲美的干细胞）通过相关技术获得的成活且具有繁殖能力的小鼠。2009年，我国干细胞研究因“小小”而受到国际干细胞研究人员的关注。因为“小小”证实了iPS细胞与胚胎干细胞具有相似的多能性，并提示了科研人员利用iPS细胞替代胚胎干细胞应用于器官移植、基因治疗等方面的可能。     

西班牙科学家用头发培育出多能干细胞

诱导式多能干细胞具备人体胚胎细胞和成熟细胞两种干细胞在医学应用方面的优点，但是其培育过程却十分困难且低效。巴塞罗那再生医学中心的科学家采用新方法，用一根头发就可以获得诱导式多能干细胞，将这种细胞培育过程效率提高了100倍，而且这种多能干细胞的增殖能力和发育的多样性与胚胎细胞不相上下。     

昆明鼠胚胎干细胞的分离培养与鉴定

目的：从昆明系小鼠的早期胚胎分离和培养胚胎干细胞(ES细胞)．方法：收集小鼠3．5d胚龄的囊胚，将其培养在小鼠胚胎成纤维细胞饲养层上，5—6d后取隆起生长的内细胞团块分离后再培养，观察集落的生长情况并通过碱性磷酸酶染色、原位杂交、细胞核型分析等对细胞集落进行鉴定．结果：KS细胞集落性生长，符合小鼠胚胎干细胞的一系列特性．结论：昆明系小鼠囊胚在胚胎成纤维细胞饲养层上可以发育成ES细胞，并能进行传代培养．     

韩国利用人类胚胎干细胞治愈下肢坏死实验鼠

韩国抱川中文医科大学附属车氏医院教授郑炯敏和汉阳大学教授金炳洙带领的一个联合研究小组表示，该小组的研究人员在实验中掌握了将人类胚胎干细胞诱导分裂为治疗用的ES细胞（血管内皮细胞）的技术，以及分离和培养这些细胞的有效方法，日前更利用这项技术获得了一种血管细胞，并且使用这种血管细胞成功治愈了患有下肢血管闭塞症的实验鼠。在实验中，     

日开发高效培育肝脏细胞技术

新华社东京1月17日电（记者蓝建中）：日本科学家开发出一种用胚胎干细胞高效培育肝脏细胞的技术，能够使90％的小鼠胚胎干细胞发育成肝脏细胞，效率相当于原有方法的约9倍。     

围着床期小鼠胚胎表达肿瘤易感基因101(TSG101)

揭示肿瘤易感基因101(TSG101)在围着床期胚胎中的时空表达型。方法:收集囊胚、培养获得着床前、着床后以及长开的小鼠胚胎。利用全胚原位杂交以及全胚免疫染色方法检测围着床期小鼠胚胎中TSG101的时空表达型。结果:TSG101表达于围着床期胚胎的內细胞块和滋养层细胞中,其中内细胞块细胞中的表达更强。结论:围着床期胚胎表达TSG101,暗示TSG101在胚胎着床过程中发挥作用。     

原子力显微镜对BALB/c小鼠胚胎干细胞表面形貌的研究

以BALB／c小鼠胚胎干细胞为对象,在大气下用原子力显微镜对其进行成象。由所获得的原子力显微图象可知,BALB／c小鼠胚胎干细胞呈圆形,表面结构致密,细胞大小不一,并且是中间高四周低的形状。     

共培养法获得MC15—昆明嵌合鼠

嵌合鼠的获得是通过ＥＳ细胞途径得到转基因小鼠的关键环节。以ＭＣ１５为供体ＥＳ细胞，用昆明品系小鼠８细胞期的胚胎为受体胚胎，采用共培养方法我们获得了２只毛色嵌合鼠。通过与囊胚显微注射法比较，表明这种方法是方便可行的。     

绵羊胚胎干细胞的分离与增殖培养

研究了囊胚(胚龄、处理方法)、传代方法(机械法和酶法)及培养液对绵羊类胚胎干细胞生长的影响,建立了绵羊类胚胎干细胞的分离培养体系.结果表明,实验获得的体外受精胚用于类胚胎干细胞的分离,具有较好的增殖及传代能力;囊胚的质量和胚龄影响绵羊类胚胎干细胞的贴壁及增殖;机械切割(半胚法)处理囊胚,可获得跟免疫法相近的内细胞团贴壁率(半胚法46%,免疫法53.6%);添加了一定浓度的胎牛血清、细胞生长因子、胰岛素及维生素C的DMEM高糖培养液可一定程度地促进类胚胎干细胞的增殖,适于绵羊类胚胎干细胞的培养.     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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-