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排序方式: 共有2222条查询结果,搜索用时 15 毫秒
91.
Chapdelaine Pierre; Moisset Pierre-Alain; Campeau Philippe; Asselin Isabelle; Vilquin Jean-Thomas; Tremblay Jacques P. 《Protein engineering, design & selection : PEDS》2000,13(9):611-615
Transfection and transduction studies involving the use of thefull-length dystrophin (11 kb) or the truncated mini-gene (6kb) cDNAs are hampered by the large size of the resulting viralor non-viral expression vectors. This usually results in verylow yields of transgene-expressing cells. Moreover, the detectionof the few transgene-expressing cells is often tedious and costly.For these reasons, expression vectors containing the enhancedgreen fluorescent protein (EGFP) fused with the N-termini ofmini- and full-length human dystrophin were constructed. Theseconstructs were tested by transfection of Phoenix cells withEffectene, resulting after 48 h in a green fluorescent signalin 20% of cells. Analysis of the cell extracts by immunoblottingwith the use of a monoclonal antibody specific to the dystrophinC-terminus confirmed the expression of EGFPmini- (240kDa) and EGFPfull-length human dystrophin (450 kDa) fusionproteins. Moreover, following the in vivo electroporation ofthe plasmids containing the EGFPmini- and full-lengthdystrophin in mouse muscles, both fluorescent proteins wereobserved in cryostat sections in their normal location underthe plasma membrane. This indicates that the fusion of EGFPto dystrophin or mini-dystrophin did not interfere with thenormal localization of the protein. In conclusion, the fusionof EGFP provides a good tool for the search of the best methodsto introduce mini- or full-length dystrophin cDNA in the cells(in vitro) or muscle fibers (in vivo) for the establishmentof a treatment by gene therapy of Duchenne muscular dystrophypatients. 相似文献
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93.
Jacques Demongeot Nicolas Glade Andr��s Moreira Laurent Vial 《International journal of molecular sciences》2009,10(8):3420-3441
A number of small RNA sequences, located in different non-coding sequences and highly preserved across the tree of life, have been suggested to be molecular fossils, of ancient (and possibly primordial) origin. On the other hand, recent years have revealed the existence of ubiquitous roles for small RNA sequences in modern organisms, in functions ranging from cell regulation to antiviral activity. We propose that a single thread can be followed from the beginning of life in RNA structures selected only for stability reasons through the RNA relics and up to the current coevolution of RNA sequences; such an understanding would shed light both on the history and on the present development of the RNA machinery and interactions. After presenting the evidence (by comparing their sequences) that points toward a common thread, we discuss a scenario of genome coevolution (with emphasis on viral infectious processes) and finally propose a plan for the reevaluation of the stereochemical theory of the genetic code; we claim that it may still be relevant, and not only for understanding the origin of life, but also for a comprehensive picture of regulation in present-day cells. 相似文献
94.
In the recent situation of a historically high nickel price, austenitic stainless steels, such as 1.4301, became too expensive compared to their actual technical value in many applications. This paper presents two new stainless steel grades developed by ArcelorMittal to replace 1.4301. The first one is a 20%Cr ferritic grade. The second one is a low‐Ni Cu‐bearing austenitic grade. The choices in the compositions are described as a function of the technical requirements, economical target and the production process limitations. The final properties are discussed as a function of the composition and compared with 1.4301 and other existing stainless steels. Finally, the complementarities of these two new grades are highlighted in regard to the different application markets considered. 相似文献
95.
Optimum conditions for scaling up the synthesis of furyl-2 oxyrane from furfural have been determined. A continuous stirred tank reactor proved the most efficient configuration for the production of the oxirane. The kinetic model makes it possible to predict the yields of epoxide per unit volume and unit time. 相似文献
96.
Different ways for grafting ester derivatives of poly(ethylene glycol) onto chitosan: related characteristics and potential properties 总被引:1,自引:0,他引:1
The grafting of poly(ethylene glycol) functionalized by ester groups (MeO-PEG-ester) onto chitosan was studied and optimized using different reaction conditions. In a first procedure, the grafting was made from 6-O-triphenylmethyl-chitosan after protection of primary hydroxyl groups and in a second one, it was made directly onto chitosan. NMR spectroscopy was an important tool to study these reactions and the grafting is unequivocally showed up. Moreover, for each procedure, the solubility and surface properties of the obtained copolymers were evaluated and compared. 相似文献
97.
We solve the Boltzmann equation in the relaxation time approximation with parallel E and B fields parallel to the continuous fibres reinforcing a metal matrix. It is shown that this solution is identical to that described by us elsewhere, except for the addition of the cyclotron frequency. The addition of the cyclotron frequency term shows that the electrons follow helical paths as they drift down the composite. The boundary considered is either the external or the internal surface of a cylinder representing the fibre. To apply this solution to metal-matrix composite materials we assumed that the cylindrical fibres are non-conducting cylinders in a matrix of pure crystalline metal. The electron mean free path is never greater than half the fibre separation distance. In a companion paper we discuss the application of this solution to metal-matrix composites. 相似文献
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100.
Frequency representation of multipath fading on line-of-sight microwave paths is revisited together with a general point of view and with the aim of giving sound foundations of medium bandwidth modelling. Moreover some typical laws of variation of the selectivity according to the frequency and the hop length are derived. 相似文献