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LEONARD Michel 《中山大学学报(自然科学版)》2007,46(Z2):126-129
The science of services constitutes a breakthrough in the traditional way of thinking of the place of informatics in the economic development of a State,a Region,an enterprise and consequently in the teaching programs.The question is no more only a question of computer science.We are in front of a more complex situation,which requires not only a multidisciplinary approach,but an interoperable approach at the intellectual level.This paper is an introduction to this complexity and it is also an attempt to propose crucial questions about the new bachelor programs and master programs. 相似文献
174.
本书是法国埃库勒理工学院一套著名的教科书中的一本.是作者为高年级大学生讲授原子核物理相关的一些专题课发展而成的教材。作者们认为大多数核现象都可以从基于泡利原理与库仑势垒的一些简单的论证理解。因此本书并不打算对于核理论现代发展深人讨论,而是把重点放在核物理学各方面的实际应用。本书充分利用了从网上可以得到的大量核物理的实验数据资源。 相似文献
175.
Platelet shape change and aggregation 总被引:1,自引:0,他引:1
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177.
Summary A combined treatment involving a radio-sensitizing chemical and low doses of X-rays was investigated. Small quantities of iodoacetamide can cause an increase in the radiation damages of rat embryos. The possibility of inhibition of postirradiation repair mechanisms is discussed. 相似文献
178.
Van Laere AS Nguyen M Braunschweig M Nezer C Collette C Moreau L Archibald AL Haley CS Buys N Tally M Andersson G Georges M Andersson L 《Nature》2003,425(6960):832-836
Most traits and disorders have a multifactorial background indicating that they are controlled by environmental factors as well as an unknown number of quantitative trait loci (QTLs). The identification of mutations underlying QTLs is a challenge because each locus explains only a fraction of the phenotypic variation. A paternally expressed QTL affecting muscle growth, fat deposition and size of the heart in pigs maps to the IGF2 (insulin-like growth factor 2) region. Here we show that this QTL is caused by a nucleotide substitution in intron 3 of IGF2. The mutation occurs in an evolutionarily conserved CpG island that is hypomethylated in skeletal muscle. The mutation abrogates in vitro interaction with a nuclear factor, probably a repressor, and pigs inheriting the mutation from their sire have a threefold increase in IGF2 messenger RNA expression in postnatal muscle. Our study establishes a causal relationship between a single-base-pair substitution in a non-coding region and a QTL effect. The result supports the long-held view that regulatory mutations are important for controlling phenotypic variation. 相似文献
179.
Mutations in IRF6 cause Van der Woude and popliteal pterygium syndromes 总被引:25,自引:0,他引:25
Kondo S Schutte BC Richardson RJ Bjork BC Knight AS Watanabe Y Howard E de Lima RL Daack-Hirsch S Sander A McDonald-McGinn DM Zackai EH Lammer EJ Aylsworth AS Ardinger HH Lidral AC Pober BR Moreno L Arcos-Burgos M Valencia C Houdayer C Bahuau M Moretti-Ferreira D Richieri-Costa A Dixon MJ Murray JC 《Nature genetics》2002,32(2):285-289
180.
Cytochrome c oxidase, the terminal enzyme of cellular respiration in mitochondria and many bacteria, reduces O(2) to water. This four-electron reduction process is coupled to translocation (pumping) of four protons across the mitochondrial or bacterial membrane; however, proton pumping is poorly understood. Proton pumping was thought to be linked exclusively to the oxidative phase, that is, to the transfer of the third and fourth electron. Upon re-evaluation of these data, however, this proposal has been questioned, and a transport mechanism including proton pumping in the reductive phase--that is, during the transfer of the first two electrons--was suggested. Subsequently, additional studies reported that proton pumping during the reductive phase can occur, but only when it is immediately preceded by an oxidative phase. To help clarify the issue we have measured the generation of the electric potential across the membrane, starting from a defined one-electron reduced state. Here we show that a second electron transfer into the enzyme leads to charge translocation corresponding to pumping of one proton without necessity for a preceding turnover. 相似文献