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121.
结核分枝杆菌融合抗原Ag85B-ESAT6真核表达载体的构建及鉴定 总被引:1,自引:0,他引:1
以结核分枝杆菌H37Rv株的基因组作为模板,将Ag85B和ESAT6编码基因进行PCR扩增,然后采用基因剪接重叠扩增PCR法(gene SOEing)将其通过疏水甘氨酸接头(GGIGIAPG)连接融合,定向克隆至质粒Pvax1中,构建结核分枝杆菌Ag85B-ESAT6融合抗原的真核表达质粒Pvax1/AE.经单双限制性内切酶图谱、PCR产物及DNA测序分析等多种方法鉴定,证实Pvax1/AE真核表达质粒构建成功.为进一步研究其结核核酸疫苗原型的免疫保护效果奠定了基础. 相似文献
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利用DNA合成技术、DNA克隆技术、PCR扩增技术以及DNA芯片技术,结合密码学的计算复杂度理论.提出了一种基于DNA技术的加密方法.加密就是制作特殊设计的DNA混合物.解密就是根据Watson-Crick互补配对原理,在DNA芯片(microarray)上同时对数以万亿的DNA序列杂交,这体现了DNA在超大规模并行计算和超大容量的数据存储方面的巨大潜力.现有的生物技术的局限性以及计算技术的局限性为该方法提供了双重的安全保障. 相似文献
124.
阐述了DNA计算的机理及其数学原理,介绍了Adleman实验,指出了DNA计算目前的应用领域和存在的问题,并对DNA计算的发展前景进行了展望。 相似文献
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M. BraAbrem A. Najari H.‐A. Ho J.‐F. Gravel P. Nobert D. Boudreau M. Leclerc 《Advanced materials (Deerfield Beach, Fla.)》2006,18(20)
The cover image depicts biochips based on responsive nanoaggregates made from stoichiometric complexes between a cationic polythiophene and an appropriate DNA aptamer. These structures undergo a conformational transition from an unfolded to a folded (G‐quadruplex) structure in the presence of a specific target protein that results in a significant increase of the fluorescence intensity, as reported on p. 2703 by Leclerc and co‐workers. 相似文献
127.
A new method for the determination of DNA was developed with azocarmine G(AG) in the presence of cetyltrimethylammonium bromide(CTAB) by the resonance light scattering (RLS) technique. The synthetic samples were determined with satisfactory results, and the reaction mechanism was also studied. The results show that under the optimum conditions, the weak RLS signal of AG can be enhanced by DNA, which results from the formation of a new ternary complex AG-CTAB-DNA with large size. Moreover, the enhanced RLS intensity at 552 nm is directly proportional to the concentration of DNA in the range of 0 - 1.0 μg/mL for fish sperm DNA (fsDNA) and 0 - 1.5μg/mL for calf thymus DNA (ctDNA). Based on this, a new assay of DNA can be established. The detection limits (3σ) are 2. 1 ng/mL for fsDNA and 2.2 ng/mL for ctDNA, respectively. 相似文献
128.
Spectroscopy Study on Crystal Structure of Ce(NO3)3 (phen)2 and Interactions of Ce(NO3)3 (phen)2 with DNA 总被引:3,自引:0,他引:3
Inrecentyears ,Komiyaetal.[1] havefoundthatrareearthsionsmaybeoneofthestrongestcutre agentsofnucleicacids .Theexperimentalresults ,thatrareearthsrepresscancersonwholeanimalbodiesandonhumanbodies(invitro) ,indicatedthatrareearthselementsactuallyhavestrongf… 相似文献
129.
During the last hundred years, the debate over the meaning of race has retained a highly consistent core, despite evolution of the technical details. Non-Europeans, and in particular, Africans, are assigned the role of deviants and outcasts, whose claim on our common humanity remains in doubt. Each time the technical facade of these racialist arguments is destroyed, the latest jargon and half-truths from the margins of science are used to rebuild them around the same core belief in Black inferiority. Because race is in part a genetic concept, the advent of molecular DNA technology has opened an important new chapter in this story. Unfortunately, the article by D. Rowe (2005, this issue, see record 2005-00117-007) begins from mistaken premises and merely restates the racialist view using the terminology of molecular genetics. No technology--even the awe-inspiring tools now available to DNA science--can overcome the handicap of fundamental conceptual errors. Race is not a concept that emerged from within modern genetics; rather, it was imposed by history, and its meaning is inseparable from that cultural origin. By ignoring its cultural meaning the reductionist narrative about race fails--both in the narrow terms of science and as a contribution to the broader social discourse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.