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1.
研究旨在构建Npas4基因过表达慢病毒,为进一步深入探索Npas4基因的功能奠定基础。用人工合成大鼠Npas4基因c DNA片段,将其插入p CDH-CMV-MCS-EF1-cop GFP构建慢病毒表达质粒p CDH-Npas4。酶切、测序验证质粒后,将p CDHNpas4和辅助质粒共转染包装细胞293T,浓缩上清得病毒颗粒并测定病毒滴度。取病毒颗粒感染SK-N-SH细胞48 h,收集细胞采用Western blotting法检测Npas4蛋白的表达。p CDH-Npas4携载正确Npas4基因,将其包装293T细胞后能产生病毒。病毒滴度为1.05×109TU/m L。相比于转染GFP病毒对照组(GFP)和未转染对照组(control),Npas4重组慢病毒组(Npas4)的细胞Npas4蛋白表达显著增高。成功构建Npas4基因过表达的重组慢病毒载体p CDH-Npas4,并获得高效的重组慢病毒,能将外源Npas4基因导入SK-N-SH细胞,为进一步研究Npas4基因的相关功能奠定了基础。  相似文献   

2.
构建小鼠Sirt3基因过表达慢病毒载体,检测人神经母细胞瘤细胞(SK-N-SH细胞)感染Sirt3基因过表达慢病毒后Sirt3 mRNA和蛋白的表达,为在细胞和动物水平研究Sirt3的作用提供新的途径和工具。利用Genebank检索的小鼠Sirt3基因序列,人工合成法合成小鼠Sirt3基因的c DNA片段,将其克隆至慢病毒载体p CDH-CMV-MCS-EF1-cop GFP中,构建慢病毒表达质粒。进行酶切及测序验证后,将慢病毒表达质粒连同辅助包装原件载体质粒共同转染入293T细胞,收集上清,测定病毒滴度。用Sirt3基因过表达慢病毒感染SK-N-SH细胞,即为Sirt3过表达组(Sirt3);用空载体慢病毒感染的SK-N-SH细胞为空载体组(GFP);未感染病毒的SK-N-SH细胞为对照组(CON)。收集细胞后,用Real-time PCR法检测各组细胞Sirt3 mRNA的水平;用Western blotting法检测各组细胞Sirt3蛋白的表达。Sirt3基因过表达慢病毒载体构建成功,病毒滴度为1.0×10~9TU/m L。Sirt3组SK-N-SH细胞的Sirt3 mRNA和Sirt3蛋白水平均显著高于GFP组和CON组(P0.01)。成功构建的Sirt3基因过表达慢病毒载体具备高效感染力,能在SK-N-SH细胞高效过表达Sirt3,本研究结果为今后进一步在神经细胞和模型动物中研究Sirt3的作用提供了新的途径和工具。  相似文献   

3.
目的研究miR-34a-5p对卡波氏肉瘤相关疱疹病毒(Kaposi's sarcoma-associated herpesvirus,KSHV)感染的神经细胞增殖和迁移能力的影响。方法选择KSHV感染的SH-SY5Y神经细胞(SK-RG)和SH-SY5Y细胞,进行差异表达的miRNA转录组测序和生物信息学分析,通过qRT-PCR法验证SH-SY5Y、SK-RG中miR-34a-5p表达水平。采用Lipofectamine 2000分别将miR-34a-5p mimics与miR-NC转染至SK-RG细胞,qRT-PCR检测转染效果。采用MTT法及平板克隆实验检测细胞增殖能力。通过Transwell及划痕实验比较两组细胞的迁移能力。采用Target Scan分析miR-34a-5p与候选靶基因c-fos基因3'UTR区的结合位点,采用双荧光素酶报告基因实验检测miR-34a-5p和c-fos 3'UTR区的靶向调控关系以分析其作用机制。采用Western blot在转染miR-34a-5p mimics与miR-NC的细胞中检测靶基因c-fos的表达。结果转录组测序结果及qRT-PCR验证均提示,SK-RG细胞中miR-34a-5p的水平低于SH-SY5Y细胞(P0.05)。于SK-RG细胞中过量表达miR-34a-5p后,MTT和平板克隆实验结果表明miR-34a-5p组细胞增殖能力低于miR-NC对照组(P0.05)。Transwell和细胞划痕实验结果表明,miR-34a-5p组细胞迁移能力低于miR-NC对照组(P0.05)。双荧光素酶报告基因实验结果提示miR-34a-5p可通过3'UTR区调控c-fos的表达。Western blot结果显示,miR-34a-5p可负向调控c-fos表达。结论 miR-34a-5p可能通过抑制c-fos的表达而抑制KSHV感染的神经细胞的增殖和迁移能力,可能成为治疗KSHV感染相关疾病的小分子miRNA候选药物。  相似文献   

4.
为了构建人Annexin A2基因真核表达载体。通过TRIzol法提取Hela宫颈癌细胞中总RNA,采用RT-PCR技术(逆转录-聚合酶链反应)扩增Annexin A2的基因片段,并成功构建成VR1012-Annexin A2-HA重组质粒。经酶切、测序检测其构建的正确性,将质粒瞬时转染到293T人胚肾细胞,使用免疫荧光和蛋白印迹(Western blot)法检测基因表达,使用流式细胞术检测转染后细胞凋亡率。结果表明实验成功构建了具有表达活性的Annexin A2真核表达质粒,为进一步研究Annexin A2的抗凋亡作用奠定了基础。  相似文献   

5.
研究旨在建立稳定表达HBcAg的P815/c細胞株,为评价针对HBcAg的乙肝疫苗的免疫效果提供体外感染的细胞模型。通过构建携带HBcAg基因的慢病毒表达载体质粒pLenti-Ubc-HBcAg-EGFP-3FLAG4RES-Puro,载体质粒携帯有加强型绿色荧光蛋白(eGFP)及嘌呤霉素(Puromycin)抗性标记基因,与包装质粒pLP1、pLP2以及包膜质粒pLP/VSVG共转染人胚肾293T细胞进行包装,得到携帯有HBcAg基因的重组慢病毒颗粒LV-HBcAg-Puro。经纯化、鉴定后转染小鼠肥大瘤细胞株P815细胞72h后,通过加入并维持2μg/mL的嘌呤霉素杀死未被有效感染的细胞,药物筛选约10 d后,免疫荧光及流式细胞仪检测表达GFP的细胞比例在98%以上,Western Blot可检测到转染后细胞内HBcAg的蛋白表达。成功构建稳定表达HBcAg基因的细胞株P815/C,为研究小鼠体内针对HBcAg的疫苗诱发的CTL反应提供了细胞杀伤实验的靶细胞。  相似文献   

6.
目的:利用CRISPR/Cas9基因编辑技术构建MLH1基因敲除的微卫星不稳定鼠源性结肠癌细胞Mc38和鼠源性乳腺癌细胞4T1,为研究微卫星不稳定肿瘤在抗肿瘤免疫治疗过程中的作用机制提供细胞模型。方法:设计2条特异性靶向MLH1基因的SgRNA序列,构建lentiCRISPRv2-SgRNA重组质粒载体,经PCR、测序鉴定;将lentiCRISPRv2-SgRNA重组质粒载体分别和慢病毒包装骨架质粒pMD2.G、psPAX2共转染293T细胞构建lentiCRISPRv2-SgRNA慢病毒载体;利用lentiCRISPRv2-SgRNA慢病毒载体分别感染Mc38、4T1细胞,经嘌呤霉素和96孔板流式分选筛选出阳性单克隆细胞后PCR、Western Blot和测序鉴定;MLH1-/-Mc38细胞、MLH1-/-4T1细胞连续培养约70 d,经荧光PCR-毛细管电泳进行微卫星状态检测,筛选MLH1基因敲除的微卫星不稳定Mc38、4T1细胞。结果:测序结果表明成功构建lentiCRISPRv2-SgRNA重组质粒载体;PCR、Western Blo...  相似文献   

7.
目的:克隆人全长Notch1基因,构建人全长Notch1/p CMV6-Entry真核重组质粒并在HEK293 T细胞中进行瞬时表达.方法:采用PCR公知不认方法扩增人全长Notch1基因并克隆到真核表达载体p CMV6-Entry中并用限制性内切酶分析和DNA测序鉴定重组质粒.将该重组质粒转染HEK293 T细胞24h后,通过实时荧光定量PCR(q-PCR)和Western blot检测鉴定人全长Notch1的表达.结果:成功构建了人Notch1/p CMV6-Entry重组真核表达质粒,人全长Notch1基因在mRNA和蛋白水平上的表达显著高于p CMV6-Entry载体对照组和HEK293 T细胞对照组.结论:克隆获得人全长Notch1基因并验证在HEK293 T细胞中表达.  相似文献   

8.
为了检测柔嫩艾美耳球虫(Eimeria tenella,Et)丝氨酸蛋白酶抑制剂(Serine protease inhibitor,Serpin)基因(EtSerpin)在真核细胞293T中的表达情况,以Et孢子化卵囊cDNA为模板,经PCR扩增含完整Serpin开放阅读框的序列,将其克隆至pGEM-Teasy载体,构建pGEM-Teasy-EtSerpin质粒,双酶切回收目的片段后与相应酶切的真核表达载体pCAGGS连接,构建真核重组表达质粒pCAGGS-EtSerpin.该重组质粒经酶切和测序鉴定正确后转染293T细胞,用间接免疫荧光法和Western blot鉴定EtSerpin基因的表达情况,间接免疫荧光实验可以检测到红色荧光,Western blot结果显示出大小约45.5kDa的目的蛋白条带,结果表明构建的EtSerpin可以在293T细胞中获得表达.  相似文献   

9.
目的:建立过表达细胞珠蛋白Cytoglobin(CYGB)的人肝细胞LO-2稳定株,初步探究CYGB对LO-2细胞生长增殖的影响.方法:采用PCR法扩增CYGB编码基因,并通过GATEWAY克隆技术构建慢病毒重组表达载体Plenti-N-GFP-CYGB;酶切、测序鉴定后,与包装质粒三质粒共转人肾上皮细胞(HEK293T),收集、浓缩含病毒上清,获得病毒颗粒;感染LO-2细胞并采用流式细胞分选技术筛选稳定细胞株,Western blot检测表达情况;使用CCK-8试剂盒检测过表达CYGB对LO-2细胞增殖的影响,通过流式细胞技术检测过表达CYGB对LO-2细胞凋亡的影响.结果:慢病毒重组表达载体Plenti-N-GFP-CYGB双酶切鉴定以及基因序列比对鉴定均正确.三质粒共转HEK293T细胞后,荧光显微镜下观察大部分细胞出现绿色荧光;收集病毒颗粒并感染LO-2细胞后,经流式细胞分选技术筛选获得稳定表达CYGB的细胞,Western blot鉴定显示,LO-2稳定株组的CYGB表达条带明显,阴性对照组未出现条带.CCK-8法绘制的细胞生长曲线显示,稳定表达细胞组的细胞生长速率低于阴性对照组,有统计学差异(P0.01).流式细胞技术检测各组LO-2细胞凋亡情况结果显示,稳定表达细胞组的细胞凋亡百分比高于阴性对照组(P0.05).结论:成功构建慢病毒重组表达载体Plenti-N-GFP-CYGB;建立稳定表达CYGB的人肝细胞株LO-2-GFP-CYGB以及阴性对照组细胞株LO-2-GFP;稳定表达CYGB的肝细胞生长速率较阴性对照组肝细胞降低,稳定表达CYGB的肝细胞凋亡百分比高于阴性对照组肝细胞;为CYGB与其蛋白的相互关系研究提供了细胞模型.  相似文献   

10.
为探讨DLL3(human notch ligand delta-like 3)过表达对人小细胞肺癌细胞的影响及可能的作用机制,通过PCR方法扩增人DLL3基因全长序列,并克隆至慢病毒表达载体Lenti-EFS-FLAG-puro而构建人DLL3基因过表达慢病毒表达质粒,酶切及测序鉴定质粒正确。通过慢病毒包装及感染,构建DLL3稳定过表达的人小细胞肺癌细胞株,并通过Western blot验证DLL3蛋白的表达。采用CCK-8法检测DLL3过表达对人小细胞肺癌细胞的增殖的影响。采用平板克隆实验检测DLL3过表达对人小细胞肺癌细胞的克隆形成的影响。Western blot检测DLL3过表达对细胞周期相关蛋白Cyclin D1,Cyclin D3的表达水平的影响。结果表明:人DLL3过表达慢病毒表达质粒构建成功; CCK-8实验显示DLL3过表达促进人小细胞肺癌细胞的增殖。平板克隆实验显示DLL3过表达提高人小细胞肺癌细胞的克隆形成能力。Western blot结果表明DLL3过表达增加细胞周期蛋白Cyclin D1,Cyclin D3的表达水平。可见DLL3过表达对人小细胞肺癌细胞的增殖具有促进作用。  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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。  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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