首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2476篇
  免费   105篇
各国政治   123篇
工人农民   60篇
世界政治   92篇
外交国际关系   455篇
法律   1206篇
中国共产党   19篇
中国政治   124篇
政治理论   238篇
综合类   264篇
  2024年   3篇
  2023年   40篇
  2022年   41篇
  2021年   37篇
  2020年   95篇
  2019年   116篇
  2018年   109篇
  2017年   123篇
  2016年   96篇
  2015年   75篇
  2014年   80篇
  2013年   247篇
  2012年   128篇
  2011年   115篇
  2010年   56篇
  2009年   97篇
  2008年   130篇
  2007年   187篇
  2006年   146篇
  2005年   124篇
  2004年   120篇
  2003年   88篇
  2002年   79篇
  2001年   54篇
  2000年   50篇
  1999年   28篇
  1998年   17篇
  1997年   9篇
  1996年   8篇
  1995年   8篇
  1994年   11篇
  1993年   9篇
  1992年   9篇
  1991年   13篇
  1990年   5篇
  1989年   9篇
  1988年   6篇
  1987年   2篇
  1986年   7篇
  1985年   1篇
  1984年   2篇
  1979年   1篇
排序方式: 共有2581条查询结果,搜索用时 31 毫秒
931.
The State Department ranks countries on adherence to minimum standards set forth by the Trafficking Victims Protection Act 2000. The Trafficking in Persons Report (TIP) is updated annually and failure to enact changes to combat trafficking results in higher tier rankings. This paper evaluates the TIP by situating this tool in light of special features of the modern era, such as globalization and risk. Through a survey of the theoretical literature on risk and on trafficking risk factors, we devise six preliminary risk clusters and discuss how the TIP could incorporate governments’ response to trafficking risk factors into the ranking system. Our intentions are to spark debate about how risk factors could be incorporated in the TIP, to provide a preliminary model and to encourage further research in this area.  相似文献   
932.
目的寻找SCN2B、SCN4B基因的变异位点,探讨其与青壮年不明原因夜间睡眠中猝死(SMDS)的关系。方法提取SMDS病例组及健康对照组的基因组DNA,采用聚合酶链式反应(PCR)方法扩增SCN2B、SCN4B基因编码区外显子、外显子-内含子交界区以及3'侧翼区序列,直接行DNA测序以明确遗传变异类型。结果在病例组中共检测到4个变异位点,c.237+27AG,c.*38CT,c.174CT(p.C58C)和c.*7CT。结论本研究首次对中国人SMDS病例进行了SCN2B、SCN4B基因的检测,上述基因是否为中国人SMDS的易感基因尚有待进一步研究证实。  相似文献   
933.
混合STR分型的解释及分析一直是国际上法医物证领域研究的热点和难点。随着DNA检验技术的发展,案件中检出的混合STR分型呈现出模板量降低以及混合组分数增加的趋势,其解释变得愈加复杂,传统的人工分析方法已难以满足现实要求。近几年国外基于统计算法模型的自动化软件解析方法渐趋成为混合STR分型分析的主要方法。本文综述了混合STR分型分析方法的相关研究进展,包括人工为主的定性分析方法以及基于统计模型的基因型概率分析方法;讨论了混合STR分型分析方法的未来发展趋势以及人工智能技术的应用前景。  相似文献   
934.
信息通信技术的使用给国际和平与国家安全带来威胁,而网络安全国际规范还处在生成的过程中。各国政府致力于达成一定的规范共识,但常常受到国家间政治博弈的影响。在此情况下,互联网企业及非政府组织开始以“自下而上”的方式积极参与到规范制定中,并提出了不少有别于现有规范成果的规范倡议。互联网企业及非政府组织期望严格约束国家的网络空间行为,并在网络安全治理中扮演更重要的角色。它们提出的规范倡议从多个方面弥补了现有规范的不足。在现实中,主导规范制定的国家行为体与非国家行为体既相互利用,又持续博弈,互联网企业及非政府组织在规范制定进程中的权力与影响力受限。联合国信息安全开放式工作组及少部分国家有限度地向非国家行为体开放,使经过挑选的部分规范倡议进入政府间规范讨论议程,但国家间的分歧与博弈又阻止了这些规范倡议成为受到认可的国际规范。尽管如此,国家间博弈方式的转变,即越来越多的国家利用互联网企业及非政府组织的力量为政治博弈服务,以及公私关系更为平衡的新型网络安全治理模式的构建,为互联网企业及非政府组织争取更大的规范制定权力提供了机会。  相似文献   
935.
犬瘟热病毒RT-nested PCR检测方法的建立与应用   总被引:1,自引:0,他引:1  
根据犬瘟热病毒(CDV)弱毒株Onderstepoort的核衣壳蛋白(NP)基因序列设计了套式引物,建立了RT-nested PCR检测方法。特异性试验表明,该法可以特异扩增出CDV NP基因片段,但从RNA病毒狂犬病病毒(RV)、犬副流感病毒(CPIV)、犬冠状病毒(CCV),DNA病毒犬细小病毒(CPV)、犬腺病毒(CAV)及正常Vero细胞中均不能扩增出条带。敏感性试验表明,RT-PCR可以扩增10-6稀释度的病毒RNA,而建立的RT-nested PCR可以扩增到10-9稀释度的病毒RNA,后者的敏感性明显高于前者。用RT-nested PCR法检测了2006年我国东北地区临床表现犬瘟热症状的病例19例,检出率达90%,明显高于RT-PCR的检出率(45%)。部分病例扩增片段的测序结果表明,CDV NP基因出现个别碱基变异。研究结果表明,建立的犬瘟热病毒RT-nested PCR方法敏感、特异,适用于动物犬瘟热的快速诊断。  相似文献   
936.
Crime scene investigators and laboratory analysts use chemical tests to detect and differentiate body fluids. Testing often requires a sample of the stain, and the chemicals may cause degradation of the fluid or interfere with subsequent tests. Colorimetric chemical tests do not differentiate between different types of the same fluid, such as venous and menstrual blood, and there is no presumptive test available to simultaneously differentiate several body fluids. In this study, we recorded ATR FT ‐IR spectra of venous and menstrual blood, semen, saliva, and breastmilk. Neat and simulated casework body fluid samples were analyzed on cotton, nylon, wood, paper, and glass substrates. Differences in fluid composition, including proteins and small molecules, resulted in spectral differences. Venous and menstrual blood is differentiated by the peak at 1039 cm?1 attributed to phosphoric acid found in menstrual blood. Peak intensity is influenced by the porosity and weave of the substrate fabric.  相似文献   
937.
In the current study, we extend the gene‐by‐environment interaction (cGxE) literature by examining how a widely studied polymorphism, the MAOA upstream variable number tandem repeat (MAOA‐uVNTR) interacts with distal and proximal stressors to explain variation in crime and delinquency. Prior research findings have revealed that MAOA‐uVNTR interacts with single indicators of environmental adversity to explain criminal behavior in general‐population and incarcerated samples. Nevertheless, the genetically moderated stress sensitivity hypothesis suggests that increased risk for criminal behavior associated with variation in the MAOA‐uVNTR can be best understood in the context of both distal stress during childhood and proximal stress in adulthood. Therefore, we employed Tobit regression analyses to examine a gene–distal–proximal environment (CGxExE) interaction across gender in a sample of university students (n = 267) and with data from the National Longitudinal Study of Adolescent to Adult Health (Add Health; n = 1,294). The results across both sets of analyses demonstrate that variation in the MAOA‐uVNTR interacts with distal and proximal stress to lead to increased risk for criminal behavior in males. Although proximal life stress is associated with an increase in crime and delinquency, this effect is more pronounced among MAOA‐L allele carriers that have experienced distal stress.  相似文献   
938.
《国际相互影响》2012,38(4):283-297

This paper consists of three parts. First, it investigates the rationality assumption behind much deterrence theorizing and arrives at the conclusion that the rationality assumption is not fully compatible with credible retaliation. Moreover, the requirements of central deterrence and of extended deterrence tend to be incompatible with each other. Since theoretical deliberations call the persisting reliability of deterrence into question, alternatives to deterrence have to be considered. The second part of the paper therefore investigates strategic defense as an improvement over deterrence and a possibly stabilizing element in deterrence. The final part refers to conceivable conflicts of interests between the USA and Western Europe concerning SDI. It is argued that such conflicts of interest either arise from parochial concerns or from overlooking the comparative advantages of free and totalitarian systems in the production of military power.  相似文献   
939.
《国际相互影响》2012,38(4):443-461
Many observers contend that wartime civilian victimization is an instrument of political leaders to achieve a particular goal. This article examines whether retaliation for similar acts by the other side, the developments on the battlefield, or the behavior of international actors accounts for the ups and downs of this so-called one-sided violence. Using information from the Konstanz One-Sided Violence Event Dataset and other sources, we evaluate the empirical relevance of these complementary models statistically. Time series analyses of the weekly number of killed and harmed Muslims (Bosniacs) and Serbs during the Bosnian civil war support the military and the massacre logic. We show that the Serbian side decreased one-sided violence following a territorial conquest, but that its one-sided violence was not a reciprocal response to the Bosniac targeting of civilians. Conversely, the Bosniac side resorted to violence during times of increasing Serbian atrocities and when the fighting was particularly intense. The analysis reveals that most international interventions did not reduce the carnage, but that the Serbs responded to Russian moves.  相似文献   
940.
猪链球菌血清2型环介导等温扩增快速检测方法的建立   总被引:1,自引:0,他引:1  
为了建立快速、灵敏的猪链球菌血清2型(SS2)LAMP检测方法,根据GenBank登录的SS2特异的荚膜多糖(cps2 H)基因序列作为检测靶标,在其序列的保守区域设计LAMP引物,利用参考菌株S735基因组DNA为模板进行扩增,优化了LAMP的反应条件和反应体系,并进行了敏感性、特异性和重复性试验。结果,利用建立的LAMP方法对SS2进行扩增,扩增产物显色呈现阳性反应,电泳出现阶梯状条带,最低检测量为0.186fg/μL模板DNA,比常规PCR高1 000倍;且与其他常见的细菌无交叉反应。结果表明,建立的LAMP方法具有灵敏、特异、快速和重复性强等优点,适用于猪链球菌病的实验室快速检测。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号