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11.
品牌竞争力的DNA模型解析   总被引:2,自引:0,他引:2  
通过建立品牌竞争力的DNA模型对品牌竞争力进行了探索。DNA模型以品牌显性竞争能力和隐性竞争能力为双链,形成双螺旋结构,并以品牌市场能力、品牌领导能力、品牌创新能力和品牌文化能力为碱基,形成具有生物活性的DNA结构,从而打造出具有独特性和可遗传性的竞争优势。最后,用DNA模型对海尔的品牌竞争能力进行分析,清晰地呈现了海尔品牌的强势基因,为企业提升品牌竞争力提供了一种分析方法。  相似文献   
12.
本文用常规方法测定了雅卡凯门鳄(caiman yacane)、新几内亚鳄(crocodylus novaeguineae)等2种鳄类的约400bp的mtDNA12SrRNA基因片段的部分序列,所测序列与GenBank中的其他18种鳄类的12SrRNA基因相应片段同源序列一起经Clustal X1.8软件进行比对,并以乌龟(chinemys reevesii)为外群,用ClustalX(1.8),Mega2软件以及paup软件将这20种鳄的12SrRNA基因部分序列进行比对后构建了20种鳄的进化关系树,并分别用NJ树,MP树探讨它们之间的系统发生关系。其结果显示:食鱼鳄属Gavialis与马来假食鱼鳄属Tomistoma的亲缘关系较近,构成姐妹群并位于鳄科分支的基部。非洲窄吻鳄(Crocodylus cataphractus)与骨喉鳄(Osteolaemus retraspis)形成姐妹群,它们的亲缘关系比与其它真鳄类的关系更近,赞同非洲窄吻鳄应从鳄属中独土出来归属于长吻鳄属Mecistops的观点,因此鳄科包括鳄属、骨喉鳄属和长吻鳄属,它们的关系为(鳄属(骨喉鳄属,长吻鳄属))。鼍科4属中凯门鳄属与黑鳄属关系最近,接下来的是古鳄属、鼍属,而且鼍属是鼍科中起源最早的类群。扬予鳄(Alligator sinensis)与密河鳄(Alligator mississippiensis)较近的亲缘关系得到支持,但它们并没有形成姐妹群关系。  相似文献   
13.
We consider the problem of statistically evaluating the similarity of DNA intronic regions of genes. Present algorithms are based on matching a sequence of interest with known DNA sequences in a gene bank and are designed primarily to assess homology among exonic regions of genes. Most research focuses on exonic regions because they have a clear biological significance, coding for proteins, and therefore tend to be more conserved in evolution than intronic regions. To investigate whether the intronic features of genes whose expression is highly sensitive to environmental perturbations differ from genes that have a more constant expression, a collection of oncogenes, tumor suppressor genes, and nonregulatory genes involved in energy metabolism are compared. An analysis of the features of these genes' intronic regions result in clustering by regulatory group. In addition, Billingsley's test for Markov structure (1961) suggests that 67% of the intronic regions in this collection of genes show evidence of nonrandom structure, indicating the possibility of a biological function for these regions. The result of Billingsley's test for homology is used as input to a clustering algorithm. The biological significance of this methodology lies in the identification of groups based on the intronic regions from genes of unknown function. With the advent of rapid sequencing techniques, there is a great need for statistical techniques to help identify the purpose of poorly understood portions of genes. These methods can be utilized to assess the functional group to which such a gene might possibly belong.  相似文献   
14.
The availability of the next generation sequencing (NGS) technology in today's biomedical research has provided new opportunities in scientific discovery of genetic information. The high-throughput NGS technology, especially DNA-seq, is particularly useful in profiling a genome for the analysis of DNA copy number variants (CNVs). The read count (RC) data resulting from NGS technology are massive and information rich. How to exploit the RC data for accurate CNV detection has become a computational and statistical challenge. We provide a statistical online change point method to help detect CNVs in the sequencing RC data in this paper. This method uses the idea of online searching for change point (or breakpoint) with a Markov chain assumption on the breakpoints loci and an iterative computing process via a Bayesian framework. We illustrate that an online change-point detection method is particularly suitable for identifying CNVs in the RC data. The algorithm is applied to the publicly available NCI-H2347 lung cancer cell line sequencing reads data for locating the breakpoints. Extensive simulation studies have been carried out and results show the good behavior of the proposed algorithm. The algorithm is implemented in R and the codes are available upon request.  相似文献   
15.
针对物体外形轮廓特征,给出一种基于主动式光电传感器的轮廓特征提取方法,该方法是通过物体经过传感器组视场时各传感器输出状态来获取特征信息;并结合稀疏表示理论,提出一种基于稀疏表示的目标轮廓识别算法,该算法是将测试样本投影到稀疏域,依据系数的稀疏性对测试样本进行分类。数值仿真与实验结果表明:采用光电传感器组获取的信息能够有效地描述物体;且通过本文算法对不同类型物体进行分类,具有良好的识别效果;对不同条件下获得的特征样本进行分类时,具有良好的鲁棒性。  相似文献   
16.
Non-coding deoxyribonucleic acid (DNA) can typically be modelled by a sequence of Bernoulli random variables by coding one base, e.g. T, as 1 and other bases as 0. If a segment of a sequence is functionally important, the probability of a 1 will be different in this changed segment from that in the surrounding DNA. It is important to be able to see whether such a segment occurs in a particular DNA sequence and to pin-point it so that a molecular biologist can investigate its possible function. Here we discuss methods for testing the occurrence of such a changed segment and how to estimate the end points of it. Maximum-likelihood-based methods are not very tractable and so a nonparametric method based on the approach of Pettitt has been developed. The problem and its solution are illustrated by a specific DNA example.  相似文献   
17.
旋形图式和旋形装饰是楚器物装饰的一种普遍现象,它是由楚人创造的、普遍流行于春秋战国时期的一种富有时代气息的新样式,是对原始旋纹的继承和发展。透过形态看观念,楚旋形图式既内含着楚文化的宇宙哲学观念,又因表征楚风楚俗而隐含了楚人的宗教信仰。作为较早出现的结构样式,它对秦汉以及后世中国传统装饰艺术产生了巨大影响。  相似文献   
18.
为适应铁路工程建设中信息管理的要求 ,在现代铁路建设中引入BPR、MRP等先进管理思想 ,以WindowsDNA技术设计开发出一种基于网络的信息管理系统 ,系统采用了全局数据库管理系统结构 ,降低了系统的构建及维护成本。最后 ,给出了系统的物料管理子系统的逻辑结构示意图 ,并列出构建该系统的主要程序段。  相似文献   
19.
The utilization of DNA evidence in cases of forensic identification has become widespread over the last few years. The strength of this evidence against an individual standing trial is typically presented in court in the form of a likelihood ratio (LR) or its reciprocal (the profile match probability). The value of this LR will vary according to the nature of the genetic relationship between the accused and other possible perpetrators of the crime in the population. This paper develops ideas and methods for analysing data and evaluating LRs when the evidence is based on short tandem repeat profiles, with special emphasis placed on a Bayesian approach. These are then applied in the context of a particular quadruplex profiling system used for routine case-work by the UK Forensic Science Service.  相似文献   
20.
DNA双螺旋结构模型的建立,是生命科学史上的奇迹和里程碑,具有划时代的意义。它不仅揭开了基因遗传之谜,也是近代生物工程勃勃兴起的重要基石。文章从多个方面探讨这一伟大发现给我们带来的启示:正确的科研选题,密切的科技合作,恰当的科学方法,合理的创造性思维等等,这些都是发现DNA结构的关键。  相似文献   
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