基于PCA的SOM网络在基因数据聚类分析中的应用

把主分量分析（PCA）方法和自组织特征映射网络（SOM）相结合,应用到基因数据聚类分析中。首先对基因数据集进行PCA分析,提取出少量的特征主分量,再对数据集进行降维。这些主分量基本上可以反映原数据集的综合信息,然后应用SOM网络对得到的特征分量进行聚类分析,把相似的基因划分到一个区域。实验结果表明,与单一地选用SOM网络进行聚类分析相比,该方法有较高的分类正确率及较为清晰的分类边界,是一种非常有效的聚类分析方法。     

C++中虚函数的应用

多态性是面向对象程序设计的重要特性之一, 虚函数是实现多态的基础.文章对C 中虚函数的定义进行分析,并通过程序举例来探讨虚函数的作用.     

Mapping technological trajectories of the Green Revolution and the Gene Revolution from modernization to globalization

The dynamics of technology development along the technological trajectories of the Green Revolution and the Gene Revolution could be explicated by the social morphologies of modernization and globalization. The Green Revolution was shaped by the exigencies of modernization, while the Gene Revolution is being shaped by the imperatives of neo-liberal economic globalization. Innovation, development, and diffusion of technologies followed different trajectories in these two realms because of being part of different innovation systems. Considerations of private gain and profit in the form of high returns to shareholders of agro-biotech corporations of global reach, largely, determine the dynamics of technological innovation in the Gene Revolution. Technology transfer and local adaptive work in the Green Revolution was carried out in the international public domain with the objective of developing research capacity in post-colonial Third World agriculture to increase food production to avert hunger-led political insurrection during the Cold War. Differentiating these two trajectories is important not only due to the normative implications inherent in comparing the impacts of these two “revolutions”, but also due to the important lessons we learn about how different contexts of innovation in the same technology cluster could evolve into contrasting research policy regimes.     

线性遗传程序设计比较分析

遗传程序设计是近几年各专家学者研究的热点之一。主要论述了6种线性遗传程序设计的原理,比较分析了各线性遗传程序设计的共同点和差异性,简单介绍了各遗传程序设计的应用领域,总结了针对不同的问题采用相应的遗传程序设计的方法。     

Genetic susceptibility to lead poisoning—A case report

Lead poisoning is well documented in persons occupationally exposed to lead. What is less known is, that even in persons working in lead based industries, the effect of lead and the appearance of signs and symptoms of lead poisoning is genetically determined. Three genes related to lead metabolism, exhibiting polymorphism have already been demonstrated-δALA-dehydratase, Vitamin D receptor gene and Hemochromatosis gene. These alleles determine the susceptibility of the individuals to lead. We present here a case of a lead acid battery worker, who presented without any signs and symptoms of lead poisoning except for a very high level of blood lead (82.8μg/dl and 47.5μg/dl 9 months later)     

FPN1基因多态性与HiHiLo训练后血象指标训练效果的关联性研究

目的:探讨FPN1基因多态性与HiHiLo训练效果的关联性。方法:选取70名健康受试者在模拟海拔2 800 m高度进行30 d HiHiLo训练(低氧暴露10 h/d、除白天常氧训练外,以75%.VO2max强度每周进行3次低氧训练),测定训练前、训练后第4 d、第7 d、第16 d、第23 d和第30 d的RBC、Hct和Hb等血象指标,应用PCR-RFLP方法解析基因多态性。结果:FPN1基因rs1123110和rs4145237多态性与血象指标的初始值不关联。经30 d HiHiLo训练训练后,rs1123110位点TT型RBC、Hb、Hct的平均增加量显著高于TC型;TT型Hb、Hct从第7 d、RBC从第16 d开始显著增加并持续至第30 d。rs4145237位点GG型RBC、Hb、Hct的平均增加量显著高于CG型;GG型Hb、Hct、RBC从第16 d开始显著增加,随后持续升高至第30 d。结论:rs1123110的TT型和rs4145237的GG型与HiHiLo训练效果关联,可以作为预测血象指标训练效果的分子标记。     

Controversial opinion: evaluation of <Emphasis Type="Italic">EGR1</Emphasis> and <Emphasis Type="Italic">LAMA2</Emphasis> loci for high myopia in Chinese populations

Functional studies have suggested the important role of early growth response 1 (EGR1) and Laminin α2-chain (LAMA2) in human eye development. Genetic studies have reported a significant association of the single nucleotide polymorphism (SNP) in the LAMA2 gene with myopia. This study aimed to evaluate the association of the tagging SNPs (tSNPs) in the EGR1 and LAMA2 genes with high myopia in two independent Han Chinese populations. Four tSNPs (rs11743810 in the EGR1 gene; rs2571575, rs9321170, and rs1889891 in the LAMA2 gene) were selected, according to the HapMap database (http://hapmap.ncbi.nlm.nih.gov), and were genotyped using the ligase detection reaction (LDR) approach for 167 Han Chinese nuclear families with extremely highly myopic offspring (<?10.0 diopters) and an independent group with 485 extremely highly myopic cases (<?10.0 diopters) and 499 controls. Direct sequencing was used to confirm the LDR results in twenty randomly selected subjects. Family-based association analysis was performed using the family-based association test (FBAT) software package (Version 1.5.5). Population-based association analysis was performed using the Chi-square test. The association analysis power was estimated using online software (http://design.cs.ucla.edu). The FBAT demonstrated that all four tSNPs tested did not show association with high myopia (P>0.05). Haplotype analysis of tSNPs in the LAMA2 genes also did not show a significant association (P>0.05). Meanwhile, population-based association analysis also showed no significant association results with high myopia (P>0.05). On the basis of our family- and population-based analyses for the Han Chinese population, we did not find positive association signals of the four SNPs in the LAMA2 and EGR1 genes with high myopia.     

染色体多态性与生殖异常的关系探讨

通过对生殖异常人群进行外周血染色体培养以及对G显带染色体核型分析,将染色体多态核型和正常核型人群分组,以比较两组人群的生殖异常的发生率,结果显示染色体多态组的生殖异常率高达68.6%,明显高于染色体正常组,二组比较具有高度显著性差异。提示染色体多态与生殖异常有一定的关系。     

血管紧张素转换酶基因多态性与运动能力关系的研究进展

采用文献资料法,总结和分析了ACE基因多态性与人体有氧代谢能力、肌肉力量及对人体运动能力机制等方面影响的研究成果。结果提示:ACE基因多态性与人体运动能力存在一定关联,但其通过何种途径影响运动能力尚有争议。因此,ACE基因能否作为人类运动能力的遗传标志,用于训练和运动员的科学选材,有待进一步研究。     

与体质和运动能力相关的双生子研究

双生子分析法是人类遗传学研究的经典方法,采用此法进行体质与运动能力的遗传学研究,首先要解决如遗传度公式的选择、双生子卵型的鉴别等基础问题。人类体质与运动能力的遗传学研究已有较长的历史,其领域从经典遗传流行病学发展到分子生物学,研究方法不断更新,人类对体质与运动能力遗传本质有了更深入的了解。