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1.
We extract some physical and chemical features re-lated to the occurrence of single nucleotide polymorphism (SNP) from three groups of sliding windows around SNP site,and then make the predictions about accuracy by using radial basis function (RBF) networks. The result of the forward sliding windows sug-gests that the accuracies and Matthews correlation coefficient (MCC values) ascend with the increasing of length of sliding windows. The accuracies range from 73.27 % to 80.69 %,and MCC values range from 0.465 to 0.614. The backward sliding windows and the sliding windows with fixed length three are de-signed to find the crucial sites related to SNP. The results imply that the occurrence possibility of SNP relies heavily on the above physical and chemical features of sites which are at a distance around 20 bases from the SNP site. Compared with the support vector machine (SVM),our RBF network approach has achieved more satisfactory results.  相似文献   

2.
Based on the thermal stress distribution for functionally gradient material (FGM) plates, a Genetic Algorithm (GA) method for the thermal stresses optimum design of FGM plate with computer technologies is given. The minimum thermal stresses combination distribution for FGM is obtained.  相似文献   

3.
研究目的:创新要点:通过分析miRNA的核心启动子和顺式作用元件为进一步解析大豆(Glycinemax)miRNAs表达调控及其功能研究提供重要信息。利用生物信息学方法全面解析了大豆降解组文库miRNA的启动子特征,并依据顺式作用元件及靶基因构建了miRNA的表达与生长素响应因子、赤霉素响应因子之问存在潜在的负反馈调控网络。研究方法:本研究利用TSSP程序和PlantCARE数据库预测了来自大豆降解组文库的440个miRNA的核心启动子以及369个miRNAs的顺式作用元件,并依据顺式作用元件及靶基因构建miRNA调控网络。重要结论:83.86%的miRNA在其上游序列中含有启动子,8.64%的miRNA在其下游序列中含有启动子,21.59%的miRNA包含增强子。核心启动子的TATA盒与转录起始位点(TSSs)的分布相似(见图2)。此外,对转录起始位点5’端的顺式作用元件预测为miRNAs的可能功能和表达的时空性提供了线索。miRNAs的顺式作用元件和靶基因的分析显示,部分miRNA的表达与生长素响应因子、赤霉素响应因子之间存在潜在的负反馈调控(见图3)。  相似文献   

4.
促甲状腺激素(Thyroid stimulating hormone,thyrotropin,TSH)由脑垂体前叶的嗜碱性细胞分泌,以游离的形式存在于血液中,含量很低,性质稳定的一种糖蛋白激素。主要生理功能是促进甲状腺的发育和分泌,从而影响全身的代谢。鉴于TSH检测结果的重要临床意义,其检测方法有很多,主要有放射免疫分析,免疫放射分析等。随着生物、化学以及材料等学科的发展,科学家们正在努力寻求更准确、更便捷、低成本的检测方法,为内分泌疾病的临床诊断提供快速、准确的数据。  相似文献   

5.
The association between the estrogen receptor a gene (ESR1) Pvull polymorphism (c.454-397T〉C) and coronary artery disease (CAD) is controversial. Thus, we conducted a meta-analysis to evaluate the relationship. Data were collected from 21 studies encompassing 9926 CAD patients and 16710 controls. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the relationship between Pvull polymorphism and CAD. The poly- morphism in control populations in all studies followed Hardy-Weinberg equilibrium. We found a significant association between ESR1 Pvull polymorphism and CAD risk in all subjects. When the data were stratified by region, a significant association between ESR1 Pvull polymorphism and CAD risk was observed in Asian populations but not in Western populations. The current study suggests that ESR1 Pvull polymorphism has an important role in CAD susceptibility.  相似文献   

6.
通过从NBS保守序列设计简并引物PCR的方法,以花椰菜(Brassica oleracea var.botrytis)抗、感黑腐病的近等基因系为材料,分离得到NBS-LRR型抗性基因同源序列,并获得1个克隆,命名为RGA330—7.Southern杂交表明,该片段在近等基因系中存在明显的多态性,且该片段在抗黑腐病基因位点至少存在3个以上类似RGA330—7的同源拷贝.序列分析结果认为该克隆与NBS—LRR型抗性基因的部分CDSs有很高的同源性,说明该片段属于NBS—LRR型.系统进化分析该序列与甘蓝型油菜的2个抗病同源序列归为一类,很可能这3个不同来源的抗性基因同源序列同属于一种抗性基因家族.因此推测该序列与花椰菜抗黑腐病基因紧密相关,为进一步克隆花椰菜抗黑腐病基因提供了可靠的候选基因,对分子标记辅助抗性育种具有重要意义。  相似文献   

7.
Rice plant architecture is an important agronomic trait that affects the grain yield. To understand the molecular mechanism that controls plant architecture, a tillering dwarf mutant with darker-green leaves derived from an indica cultivar IR64 treated with EMS is characterized. The mutant, designated as tddl(t), is nonallelic to the known tillering dwarf mutants. It is controlled by one recessive nuclear gene, TDDL(T), and grouped into the dn-type dwarfism according to Takeda’s definition. The dwarfism of ...  相似文献   

8.
陈红 《科技信息》2010,(29):I0162-I0164
本文简要介绍了概念检查性问题(CCQs)存在的目的,CCQs的定义,CCQs的设计方法,CCQs的优点和缺点,如何有效地运用CCQs。文中引用了大量实例,通俗易懂,对于英语教师正确使用CCQs具有一定的借鉴意义。  相似文献   

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