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91.
Zhanbo LEI Yoshiyasu YAMADA Jihong HUANG Youmin XI 《系统科学与复杂性》2006,19(4):538-546
Case-based reasoning (CBR) is an important reasoning technique of expert system. In this paper, the authors introduce CBR to intelligent early-warning support system, which could warn quantitatively for enterprise financial crisis and could warn qualitatively by expert's knowledge and experience. Furthermore, genetic algorithm is applied to case-based reasoning in CBR-IEWSS, which improves accuracy and efficiency of case retrieval. Last, the structure of CBR-IEWSS is given. 相似文献
92.
文中从发展对儿童适宜的生活环境的观点出发来研究城市住房项目.该项研究是针对Makahari湾城镇的中层住宅及附属教育设施的公寓区展开的.文中采用草图来确定Makahari湾城镇中儿童生活与其环境之间的关系.1999年进行首次研究,接着在2003年进行第二次研究,此间该镇的建设有所发展.具体研究是利用儿童凭记忆点出的关于他们的住宅、学校、玩耍场地和其它较多被注意的场所的草图来进行的.在两次研究期间,该地区发生了许多实体环境的变化,这些变化能从儿童的草图的许多元素中反映出来.将这些草图中的变化加以对照、分析,并将环境的改变与儿童的空间认知的关系加以探讨,同时注意分析比较体现在草图中的区域范围。结果表明,儿童早期对目标物的了解能从Makahari湾的空间结构以及环境变化中得到增强,而两者都由方格的模式构成.经验、每目的生活以及对小学和儿童游戏场所的空间认知与儿童的生活环境息息相关.此项分析揭示了在一个发展中的住宅区中儿童对其生活环境的空间认知与其附属教育设施之间的关系. 相似文献
93.
Atsuo Yamada 《复旦学报(自然科学版)》2007,(5)
1 Results As tremendous increase of interest towards the application of LiFePO4 for lithium battery cathode,the mechanism of the intrinsic transport of lithium ions and electrons in LixFePO4 is becoming the intensive and exciting research subject.In the present paper,we will mainly focus on dimension of the transport and the role of solid solution as they seem to be key issues to understand charge movement in the olivine structure.Although one-demensional lithium motion along b-axis has been theoretical... 相似文献
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95.
Interleukin-2 (IL-2) has a key role in the antigen-specific clonal growth of T lymphocytes, by virtue of its interaction with a specific cell-surface receptor (IL-2R). The growth signal seems to be delivered by IL-2 bound to the high-affinity, but not the low-affinity, receptor. Genes encoding IL-2 and its receptor (that is, Tac-antigen) have been cloned and analysed in detail. We have now achieved cell-type-specific reconstitution of the high-affinity human IL-2R by expressing the complementary DNA cloned from normal lymphocytes. A mouse T-lymphocytic line, EL-4, expressed human IL-2R with high (dissociation constant (Kd) = 160-220 pM) and low (Kd = 2.1-2.2 nM) affinity for recombinant human IL-2, while mouse L929 cells expressed only a single class of the IL-2R with lower affinity (Kd = 34.5 nM) for the ligand. We also show that the human IL-2R expressed in EL-4 cells responds to IL-2 and mediates reversed signal transduction: growth of the EL-4 cells harbouring the IL-2R is inhibited specifically by human recombinant IL-2. The approach described here may provide a general experimental framework for elucidating the molecular basis of signal transduction mediated by specific receptor-ligand interaction. 相似文献
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98.
Molecular machinery for non-vesicular trafficking of ceramide 总被引:2,自引:0,他引:2
Synthesis and sorting of lipids are essential for membrane biogenesis; however, the mechanisms underlying the transport of membrane lipids remain little understood. Ceramide is synthesized at the endoplasmic reticulum and translocated to the Golgi compartment for conversion to sphingomyelin. The main pathway of ceramide transport to the Golgi is genetically impaired in a mammalian mutant cell line, LY-A. Here we identify CERT as the factor defective in LY-A cells. CERT, which is identical to a splicing variant of Goodpasture antigen-binding protein, is a cytoplasmic protein with a phosphatidylinositol-4-monophosphate-binding (PtdIns4P) domain and a putative domain for catalysing lipid transfer. In vitro assays show that this lipid-transfer-catalysing domain specifically extracts ceramide from phospholipid bilayers. CERT expressed in LY-A cells has an amino acid substitution that destroys its PtdIns4P-binding activity, thereby impairing its Golgi-targeting function. We conclude that CERT mediates the intracellular trafficking of ceramide in a non-vesicular manner. 相似文献
99.
Early death of mice cloned from somatic cells 总被引:12,自引:0,他引:12
Ogonuki N Inoue K Yamamoto Y Noguchi Y Tanemura K Suzuki O Nakayama H Doi K Ohtomo Y Satoh M Nishida A Ogura A 《Nature genetics》2002,30(3):253-254
Here we report that the lifespan of mice cloned from somatic cells is significantly shorter than that of genotype- and sex-matched controls, most likely due to severe pneumonia and hepatic failure. This finding demonstrates the possibility of long-term deleterious effects of somatic-cell cloning, even after normal birth. 相似文献
100.