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11.
基于GM(1,1)模型的某高校招生人数预测 总被引:1,自引:0,他引:1
分析了近年来我国高校招生人数的变化趋势,并利用GM(1,1)模型对某高校2008年的招生人数进行了预测.从而为高校招生人数决策提供了依据。 相似文献
12.
Regulation of insulin receptor function 总被引:1,自引:0,他引:1
Youngren JF 《Cellular and molecular life sciences : CMLS》2007,64(7-8):873-891
Resistance to the biological actions of insulin contributes to the development of type 2 diabetes and risk of cardiovascular
disease. A reduced biological response to insulin by tissues results from an impairment in the cascade of phosphorylation
events within cells that regulate the activity of enzymes comprising the insulin signaling pathway. In most models of insulin
resistance, there is evidence that this decrement in insulin signaling begins with either the activation or substrate kinase
activity of the insulin receptor (IR), which is the only component of the pathway that is unique to insulin action. Activation
of the IR can be impaired by post-translational modifications of the protein involving serine phosphorylation, or by binding
to inhibiting proteins such as PC-1 or members of the SOCS or Grb protein families. The impact of these processes on the conformational
changes and phosphorylation events required for full signaling activity, as well as the role of these mechanisms in human
disease, is reviewed in this article.
Received 3 August 2006; received after revision 1 December 2006; accepted 8 January 2007 相似文献
13.
14.
以乙酸四氢呋喃甲酯为原料,通过自由基氯化反应,合成双脱氧核苷类抗艾滋病药物的重要中间体化合物5—0—乙酰基—2.3—双脱氧—D.L—吹喃戊糖基氯.对于此种不稳定的中间体化合物,用~1HNMR跟踪监测反应物的方法,研究了改变反应时间、反应温度和反应物摩尔比对反应产物的影响,获得了最佳的反应条件,使其收率从10%提高到50%左右. 相似文献
15.
16.
褚志仁 《汕头大学学报(自然科学版)》1995,(1)
本文把文[1]的一个具有复拟单调系数的Fourier级数L1-收敛的充要条件推广到具有复O-正则拟单调系数的Fourier级数上,所得的结果推广了文[1]和[5]的主要结论. 相似文献
17.
廖业元 《北京交通大学学报(自然科学版)》1992,(1)
在用“奇偶点图上作业法”求解“中国邮路问题”时,需检查图中的每一个回路.当图中回路较多时,检查不便且易出错.针对此,本文建立了求解“中国邮路问题”的0-1规划模型,并给出了算例。 相似文献
18.
19.
Edouard T Montagner A Dance M Conte F Yart A Parfait B Tauber M Salles JP Raynal P 《Cellular and molecular life sciences : CMLS》2007,64(13):1585-1590
Activating and inactivating mutations of SHP-2 are responsible, respectively, for the Noonan (NS) and the LEOPARD (LS) syndromes.
Clinically, these developmental disorders overlap greatly, resulting in the apparent paradox of similar diseases caused by
mutations that oppositely influence SHP-2 phosphatase activity. While the mechanisms remain unclear, recent functional analysis
of SHP-2, along with the identification of other genes involved in NS and in other related syndromes (neurofibromatosis-1,
Costello and cardio-facio-cutaneous syndromes), strongly suggest that Ras/MAPK represents the major signaling pathway deregulated
by SHP-2 mutants. We discuss the idea that, with the exception of LS mutations that have been shown to exert a dominant negative
effect, all disease-causing mutations involved in Ras/MAPK-mediated signaling, including SHP-2, might lead to enhanced MAPK
activation. This suggests that a narrow range of MAPK signaling is required for appropriate development. We also discuss the
possibility that LS mutations may not simply exhibit dominant negative activity.
Received 30 November 2006; received after revision 8 February 2007; accepted 13 March 2007 相似文献
20.
The interleukin 1β (IL-1β) cDNA was cloned from the red seabream (Pagrus major) by homology cloning strategy. A cDNA fragment was amplified by PCR using two degenerated primers, which were designed according to the conserved regions of other known IL-1β sequences, and elongated by 3' ends and 5' ends RACE PCR to get the full length coding sequence of red seabream IL-1β (RS IL-1β). The sequence contained 1252 nucleotides that included a 5' untranslated region (UTR) of 84bp, a 3' UTR of 410 bp and an open reading frame (ORF) of 759 nucleotides which could be translated into a putative peptide of 253 amino acids with molecular weight of 28.6 kD and putative isoelectric point pI of 5.29. The deduced peptide contained two potential N-glycosylation sites and an identifiable IL1 family signature, but lacked the signal peptide and the clear ICE cut site, which were common in other nonmammalian IL-1β genes. The RS IL-1β had the highest homology with piscine IL-1β according to phylogenetic tree analysis. 相似文献