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1.
电击法转移含人凝血因子Ⅸ基因重组质粒的影响因素   总被引:2,自引:0,他引:2  
反转录病毒载体在基因治疗中可能会产生野生型病毒而引起安全性问题,本文研究含FIXcDNA重组质粒基因治疗血友病B的可能,构建了不具反转录病毒载体结构的两重组质粒pSCIXTN和pCIXTN,前者含SV40早期启动子和hCMV启动子共同控制的FIX cDNA,后者仅含hCMV启动子控制的FIXcDNA,它们都含有TK启动子驱动的neo基因,通过电击法将基因转移到PA317和HT1080细胞,在HT1  相似文献   

2.
腺病毒同源重组子的鉴定   总被引:1,自引:0,他引:1  
携带入IFN-γcDNA序列的E1区缺失的腺病毒载体pAdl2/RSV-IFN-bpA与pJM17质粒,通过磷酸钙沉淀法共转染293细胞,经同源重组,共获得6个病毒噬斑。病毒噬斑感染293细胞,至出现完全细胞病变效应(CPE)后,抽提细胞内的病毒DNA,经XhoⅠ酶切后走凝胶电泳,出现重组腺病毒圾的3.5kb大小的DNA条带,^32P标记的探针pAdl2/RSV-IFN-bpA与XhoⅠ酶切过的病  相似文献   

3.
构建了带有人hFⅨ cDNA及不同调控顺序的重组质粒和反转录病毒载体,系统比较了不同启动子,增强子在不同靶细胞中对hFⅨ cDNA表达的作用,MoMLV病毒的LTR启动子在小鼠成纤维细胞中控制转录能力较强,还研究了hFⅨ基因自身内含子Ⅰ及IL-2基因内含子对hFⅨ cDNA的表达增强艇,并就双启子和选择基因对hFⅨ cDNA表达的影响进行了实验探讨。  相似文献   

4.
从家蚕核型多角体病毒(BmNPV)通用转称载体pBK283和粉纹夜蛾核型多角体病毒(TnNPV)转移载体pSXIVVI+X3系列出发,构建了一个7.2kb能形成多角体且可以用于克隆含不同读码框外源基因的BmNPV通用转移载体系列pBMX3.pBMX3系列以BmNPV多角体结构基因上游的1.9kb和下游1.3kb的片段作为与BmNPV基因组进行体内同源重组的同源序列;pSXIVVI+X3系列的SXIV双启动子用于外源基因的表达;AcNPV的多角体基因作为重组病毒形成多角体的基因.以BmNPV-LacZ(occ-gal+)为出发株病毒,pBMX3系列的重组病毒筛选有occ+和gal-两个遗传标记  相似文献   

5.
构建了含有MCK增强子,βactun启动子,及hFIX内含子1的3个载体G1NaMBAIX,G1NaMBAiIX,G1NaPAIXi‘BAM。转入PA317和成肌细胞C2C12细胞后测定hFIX的表达,发现反向构建的G1NaPAIXi’BAM表达最高且最稳定,而正向构建的G1NaMBaIix的内含子常被剪切,在C2C12细胞中表达不高。  相似文献   

6.
通过PCR扩增,得到苜蓿丫纹夜蛾核型多角体病毒(AutographacalifornicaNuclearPolyhedrosisVirus,AcNPV)具早晚期启动子元件的p35基因启动子,将其插入到杆状病毒转移载体质粒pSXIVVI+X3多克隆位点上游,使之与pSXIVVI+X3质粒中的人工合成后期启动子(PSyn)、多角体XIV启动子(PXIV)串联构成早期、晚期、极晚期能持续启动外源基因表达的转移载体质粒pSX35.将pSX35用于组建含HBsAg基因并形成多角体的重组TnNPV,HB-sAg基因的表达量显著提高,表达时间亦明显提前,从而实现了外源基因在杆状病毒表达系统的全期、高效表达.mRNA引物延伸试验结果显示,Pp35在重组病毒中可产生2套转录本,分别于病毒感染的早期和晚期起始HBsAg基因的表达.  相似文献   

7.
Tat(Transactivator)蛋白是人免疫缺陷病毒HIV基因组编码的返式式激活因子。为了进一步研究M5Tat和M6Tat蛋白对HIV病毒复制的抑制作用,将可被Tat调控的启动子YL158替换基因治疗中常用的逆转录病毒载体LNCX中的CMV启动子,构建了表达上述反显性Tat蛋白的逆转录病毒载体,随后导入双向性包装细胞PA317细胞中,用产生出的复制缺陷病毒感染MT4T淋巴细胞。用HIV-1病  相似文献   

8.
血友病B是一种由于人凝血因子Ⅸ (hFIX)缺陷导致的严重出血性遗传疾病 ,临床治疗主要依靠输血或凝血酶原复合物 ,但这些常规的替代治疗不仅费用昂贵 ,易引起输血反应 ,更可能感染肝炎病毒或爱滋病病毒 .理论上 ,只有基因治疗可望从根本上治疗血友病B .本研究先后建立反转录病毒基因转移系统 ,高效转染小鼠、大鼠、兔和血友病B患者皮肤成纤维细胞等不同细胞 ,尤其是人FIX在骨髓基质细胞的表达在国际同类研究中是首次报道 .人FIX在兔体内表达水平和持续时间在同类研究中居世界领先水平 ;在国内首先建立了有关基因治疗的安全性检…  相似文献   

9.
红细胞生成素(EPO)在中国仓鼠卵巢细胞(CHO)中稳定表达   总被引:4,自引:0,他引:4  
将EPOcDNA分别插入真核表达质粒载体pSV2dhfr和pcDNA3的适当位点,用电脉冲法导入CHO细胞,用ELISA法检测EPO的表达量,用TF1细胞检测EPO表达产物的生物活性.结果表明,用pSV2dhfr作为载体,在抗MTX阳性细胞克隆中,获得了表达EPO(258ng/mL培养液)的CHO细胞株,并且表达产物具有生物活性.进一步的传代和冻存试验表明,所得细胞株表达EPO的水平不受传代和冻存的影响  相似文献   

10.
将人尿激原cDNA分别插入家蚕核型多角体病毒转移载体pBK283和pBF4中,构建成两个重组质粒。所构建的这两个重组质粒与野生型家蚕核型多角体病毒DNA共转染家蚕培养细胞,经病毒斑实验筛选出含pro-UK cDNA的稳定重组病毒株BmNPV-pk1和BmNPV-pk2。将此两株蛋白平板溶圈测活法和Western印迹法分析细胞培养上清及细胞和家蚕的体液及组织,证实均有pro-UK表达。家蚕培养细胞的  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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