miRNA在人骨髓来源间充质干细胞成骨诱导分化过程中的表达

观察miRNAs在人骨髓来源间充质干细胞成骨诱导分化过程中的表达情况。以从骨髓中分离培养的MSCs及成骨诱导培养后的细胞为实验对象,利用基因芯片检测miRNAs的表达情况,由SAM分析得到MSCs较其诱导培养细胞中差异表达的miRNAs,再进行生物信息学分析。分离培养出的MSCs经成骨诱导培养14 d后,已具有成骨细胞特性;经芯片检测并SAM分析,成骨诱导培养的细胞较MSCs高表达的miRNAs有7个:hsa-miR-363*、hsa-miR-483、hsa-miR-590、hsa-miR-130a、hsa-miR-15b、hsa-miR-30c、hsa-miR-663;成骨诱导培养的细胞较MSCs低表达的miRNAs有6个:hsa-miR-192、hsa-miR-210、hsa-miR-128a、hsa-miR-224、hsa-miR-106a、hsa-miR-494。利用TargetScan预测其靶基因,并行生物信息学分析,其中hsa-miR-130a、hsa-miR-15b和hsa-miR-30c的预测靶基因多为维持干细胞特性的基因;而hsa-miR-106a和hsa-miR-494的预测靶基因多为参与骨形成及成骨分化的基因。为证明miRNAs参与调控MSCs的成骨分化过程提供了直接证据和研究基础。     

2种骨髓间充质干细胞生物性状的比较

比较老人和胎儿骨髓间充质干细胞(MSCs)的生物学性状,为选择抗砷细胞的种子细胞提供实验依据。取老人和胎儿骨髓MSCs,在α-MEM培养液中进行骨髓MSCs培养,测定生长曲线,细胞贴壁率及NaAsO2对骨髓MSCs的细胞毒作用。从老人和胎儿骨髓中可培养出骨髓MSCs,二者在细胞形态、生长特性等方面相似,胎儿骨髓MSCs的扩增潜能明显强于成人骨髓MSCs,胎儿骨髓MSCs对NaAsO2的耐受性比老人骨髓MSCs高。因此,从老人及胎儿骨髓中可分离培养出骨髓MSCs,在体外保持有效扩增能力。胎儿骨髓MSCs比老人骨髓MSCs更原始,具有更大的体外扩增潜能,可做为抗砷细胞的种子细胞。     

体外诱导大鼠骨髓间充质干细胞表达酪氨酸羟化酶

目的:探讨体外诱导大鼠骨髓间充质干细胞(mesenchymal stem cells,MSCs)表达酪氨酸羟化酶,为帕金森病细胞移植替代治疗提供特异性分化的细胞.方法:在无菌条件下从SD大鼠的股骨中分离骨髓间充质干细胞,体外培养传3代后,用表皮生长因子、碱性成纤维细胞生长因子和抗坏血酸诱导MSCs 表达酪氨酸羟化酶.在镜下,观察MSCs 在诱导前后的形态变化;用免疫荧光染色检测酪氨酸羟化酶的表达.结果:MSCs经诱导分化后,胞体逐渐变圆,并伸出神经轴突、树突样突起;免疫荧光化学表明细胞酪氨酸羟化酶染色呈强阳性反应.结论: SD大鼠骨髓间充质干细胞在体外能被定向诱导表达酪氨酸羟化酶,有可能为帕金森病治疗提供特异性分化的细胞.     

慢病毒介导的GFP转染对小鼠骨髓间充质干细胞表型、增殖和分化能力的影响

运用慢病毒(Lentivirus)载体构建绿色荧光蛋白(GFP)在小鼠骨髓间充质干细胞(MSCs)中的转染体系,检测转染后MSCs的表型和增殖能力,并诱导其向成肌细胞分化,检测此转染体系对MSCs细胞表型、增殖和分化能力的影响.骨髓细胞悬液破红后贴壁法培养MSCs,采用流式细胞术鉴定细胞表面标记,鉴定MSCs纯度;Lentivirus-GFP以1、10、50和100的感染复数(MOI)转染MSCs,作用48h后流式细胞术及免疫荧光法检测转染效率和表达的荧光强度;MTT法检测转染后MSCs的细胞活力.诱导MSCs-GFP向成肌细胞分化,蛋白印记法(WB)检测成肌细胞特异性蛋白desmin和α-SMA的表达.流式细胞术检测结果显示,培养的MSCs表达CD44、CD90和CD105,不表达CD34、CD45和CD188,符合干细胞特性.MOI为1、10、50和100的转染效率分别为23.45%、93.51%、95.44%和95.55%,MOI为10时,转染效率较高,且对MSCs活力无明显影响.MSCs-GFP体外经成肌细胞诱导分化后,表达特异性抗原desmin和α-SMA.表明本研究成功构建了小鼠骨髓来源MSCs的Lentivirus-GFP转染体系,有效标记了MSCs细胞,且此标记对MSCs的表型、增殖和分化能力等细胞生物学特性无明显影响.     

骨髓间充质干细胞对损伤卵巢的修复作用

目的:探讨骨髓间充质干细胞移植对损伤卵巢的修复作用。方法:通过贴壁筛选法培养、纯化GFP转基因小鼠MSCs。将健康的雌性ICR小鼠(6 w)随机分为4组:正常对照组(A组,n=6)、MSCs移植组(B组,n=6)、MSCs治疗组(C组,n=6)、损伤组(D组,n=6)。B组腹腔移植MSCs,C、D组小鼠卵巢在无菌条件下,用体积分数为10%H2O2损伤卵巢建立损伤模型,24 h后C组腹腔移植MSCs,D组注射等体积的PBS。各组每周取卵巢,采用外观拍照、PCR检测GFP基因和病理切片观察MSCs是否对损伤卵巢有修复作用。结果:PCR结果表明MSCs经腹腔移植可到达正常卵巢,也可到达受损伤卵巢;C组移植MSCs后小鼠卵巢恢复的比D组快。结论:MSCs通过腹腔移植可到达卵巢,并可促进损伤卵巢的修复。     

缺氧后小鼠脑匀浆提取液对儿童MSCs分化为神经细胞的影响

目的:观察缺氧后不同时段小鼠脑匀浆提取液对儿童骨髓间充质干细胞(MSCs)分化为神经元样细胞的影响,为筛选MSCs的最佳移植时间提供依据.方法:制作缺氧小鼠模型;并制取缺氧不同时间段脑匀浆提取液;诱导儿童MSCs;比较MSCs分化为神经元样细胞的阳性率.结果:缺氧后1、4,7、10、13 d小鼠脑匀浆提取液均可将MSCs诱导成神经元样细胞,经免疫学鉴定NES染色强阳性;但各组阳性率不同,以缺氧10 d后阳性率(21.02±3.38)%最高,与其他各组比较有统计学差异(P<0.05).结论:缺氧后小鼠脑匀浆提取液可诱导儿童MSCs分化为神经元样细胞,缺氧后10 d的分化率最高.     

人胎肝MSCs的分离、鉴定及其向脂肪和成骨细胞的分化

目的:分离纯化人胎肝中的间充质样干细胞(mesenchymal-like stem cells,MSCs),观察化学因子诱导其定向分化的作用,并初步鉴定其生物学特性.方法:利用二步离心法、羟乙基淀粉沉淀法及细胞差速贴壁生长特性分离纯化人胎肝MSCs;流式细胞仪检测其细胞周期和表面标志;添加常规诱导液诱导其向脂肪、成骨细胞分化并加以鉴定.结果:从人胎肝中成功分离纯化得到MSCs,P3代细胞有91.2%的细胞处于GO/G1期;表达CD29、CD44、CD105和CD166,不表达造血细胞标志CD15、CD34、CD45,不表达与GVHD相关的HLA-DR、CD80、CD86、CD40、CD40L.在经典诱导条件下,人胎肝MSCs可向脂肪及成骨细胞分化.结论:人胎肝中含有较丰富的MSCs,人胎肝MSCs具有多向分化潜能,且免疫原性弱,是组织工程和细胞治疗较为理想的种子细胞.     

人胎骨髓MSCs的分离鉴定及其向脂肪和成骨细胞的分化

目的:分离鉴定人胎骨髓中的间充质样干细胞(m esenchym al-like stem cell,MSCs),探索其体外培养的生物学特性。方法:利用细胞差速贴壁生长特性分离纯化人胎骨髓间充质样干细胞;利用流式细胞仪检测其细胞周期和表面标志;添加常规诱导液诱导其向脂肪、成骨方向分化,并利用特异性细胞化学染色法加以鉴定。结果:从人胎骨髓中成功分离、纯化得到间充质样干细胞,P4代细胞有92.3%的细胞处于G0/G1期;P5代细胞有96.1%的细胞处于G0/G1期;流式细胞仪检测P3代细胞结果显示:人胎骨髓MSC表达CD15、CD29、CD44、CD105、CD106和CD166,不表达造血细胞标志CD34、CD45,不表达与GVHD相关的HLA-DR、CD80、CD86、CD40、CD40L。在经典的诱导条件下,人胎骨髓MSCs可迅速向脂肪及成骨方向分化。结论:人胎骨髓中含有丰富的间充质样干细胞,具有较强的多向分化潜能,且免疫原性弱,是组织工程的较为理想的种子细胞。     

BrdU标记骨髓间充质干细胞的研究

目的:探讨5-溴脱氧尿嘧啶核苷(5-Bromo-21-deoxyuridine,BrdU)标记骨髓间充质干细胞(Mesenchymal stem cells.MSCs)的可行性.方法:分离培养骨髓MSCs,经BrdU标记不同时间,免疫细胞化学鉴定.结果:MSCs的CD44、CD54免疫细胞化学染色阳性率达90%以上.BrdU标记的阳性细胞率随标记时间延长而逐渐增高,标记72h阳性率达85%以上.结论:以10μmol/L的BrdU标记骨髓MSCs的最佳时间是72h.     

内皮祖细胞条件培养基对间充质干细胞向内皮细胞分化的影响

目的探讨体外小鼠内皮祖细胞(endothelial progenitor cells,EPCs)条件培养基(CM)对间充质干细胞(mesenchymal stem cells,MSCs)向内皮细胞(endothelial cells,ECs)分化的影响。方法全骨髓贴壁法和差速贴壁法提取培养MSCs和EPCs,流式细胞术检测MSCs和EPCs表面标记物,双荧光染色和体外成管实验对EPCs进行功能鉴定。将MSCs分为0%EPCs-CM组(对照组)、25%EPCs-CM组和50%EPCs-CM组。qRT-PCR检测各组CD31、v WF、e NOS的mRNA表达水平。体外成管实验检测各组细胞的体外成管能力;免疫荧光检测各组MSCs CD31、CD34表达情况;对各组上清中的NO进行检测。结果流式细胞术结果显示,第3代MSCs高表达Sca-1,低表达CD34、CD11b;EPCs高表达CD34、CD133和VEGFR2,可吞噬Dil-AC-LDL和结合UEA-1。在基质胶上可形成管腔样结构。qRTPCR显示3周时50%EPCs-CM组CD31、v WF、e NOS表达(2. 28±0. 25,1. 76±0. 71,8. 27±1. 65),较对照组显著升高(P0. 05)。50%EPCs-CM组MSCs可体外形成管腔样结构;免疫荧光显示50%EPCs-CM组MSCs CD31和CD34的表达明显高于对照组。对照组细胞与实验组细胞上清液中NO的含量(8. 81+3. 41,20. 93±9. 47)μmol/L,差异显著(t=3. 96,P0. 05)。结论 EPCs-CM能提高MSCs体外成管能力,并促进MSCs向ECs分化。     

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-