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   1212篇
  免费   56篇
各国政治   69篇
工人农民   79篇
世界政治   98篇
外交国际关系   94篇
法律   641篇
中国共产党   1篇
中国政治   18篇
政治理论   267篇
综合类   1篇
  2023年   13篇
  2022年   16篇
  2021年   39篇
  2020年   47篇
  2019年   54篇
  2018年   55篇
  2017年   60篇
  2016年   59篇
  2015年   48篇
  2014年   56篇
  2013年   198篇
  2012年   54篇
  2011年   50篇
  2010年   31篇
  2009年   41篇
  2008年   38篇
  2007年   65篇
  2006年   34篇
  2005年   22篇
  2004年   32篇
  2003年   26篇
  2002年   24篇
  2001年   19篇
  2000年   21篇
  1999年   11篇
  1998年   9篇
  1997年   10篇
  1996年   14篇
  1995年   13篇
  1994年   8篇
  1993年   10篇
  1992年   12篇
  1991年   10篇
  1990年   9篇
  1989年   7篇
  1988年   7篇
  1987年   4篇
  1985年   3篇
  1984年   8篇
  1983年   2篇
  1982年   3篇
  1981年   2篇
  1980年   2篇
  1979年   3篇
  1978年   3篇
  1977年   4篇
  1970年   2篇
  1969年   3篇
  1967年   1篇
  1966年   1篇
排序方式: 共有1268条查询结果,搜索用时 31 毫秒
331.
332.
In 1994 three elections were held in the Netherlands. For a time it seemed that the right-wing extremist parties were destined to break out of their marginal position. However, after these three elections, in terms of electoral support they ended up where they had started. The variation in electoral support for these parties can only in part be attributed to developments within the parties and the (negative) publicity these developments incited in the media. An alternative explanation based upon protest voting and the theory of first and second-order elections appears more promising.  相似文献   
333.
Three laboratories present a harmonised system for the retrospective comparison of south west Asian heroin. It consists of an improved gas chromatographic (GC) profiling method and a computerised data retrieval. The investigations of the GC were necessary with a view to improve the reproducibility of the system. The necessity of a strict quality control is emphasized. The peaks of the GC profile were investigated for abundance, intensity, GC behaviour (reproducibility) and correlations; 16 of them were selected for describing the heroin profile in the database. The results from intra-lab profile comparisons are reported. The reproducibility of the analysis was good and the variation between the samples was large, thus, allowing conclusions with a high degree of certainty. The criteria of similarity were defined. The system is successfully running in all three labs.In connection with inter-laboratory comparison, the aspects of method harmonisation and standardisation are discussed. It appeared that the GC method is a very subtile one, urging for a strict standardisation between the three labs. Despite a long cooperation between three well-equipped and experienced labs, a more or less serious loss of reproducibility was noticed in the inter-lab results in comparison with the intra-lab results. The loss could for the greater part be attributed to the (limits of the) GC technique; a number of compounds, necessary for making the discrimination between samples, showed difficult chromatographic behaviour, leading to insufficient inter-lab reproducibility. Using the actual variables, improvements in performance can hardly be expected in the near future. The loss of reproducibilty implies that the number of false positive matches in a database search increases. This may strongly reduce the value of a relatively large, international database. The study shows that so far, the best option for international comparison is the analysis in a central laboratory. The idea of local determination at a large number of national labs and the use of a common database is not a realistic aim for this type of analysis.  相似文献   
334.
335.
336.
ABSTRACT

Among the many ‘businesspeople’ whom the promise of commercial success has drawn to southern China in recent years one can find a small number of Kyrgyz middlemen. Working mostly with Russian-speaking clients, their job is to organize buying trips, coordinate with local manufacturers, translate, and oversee cargo shipments. Based on ethnographic fieldwork since 2013, this article examines in detail the careers, work routines and business model adopted by Kyrgyz middlemen in Guangzhou. I argue that in contrast to the early bazaar or shuttle traders, who have been operating across Eurasia since the 1990s, these Kyrgyz middlemen constitute a next kind of economic actor within more diversified, service-oriented and formalized value chains across post-Socialist Eurasia (referred to here as Business 2.0). One of these middlemen’s most salient contributions is to translate between the informal and formal domains of national economies as well as within cross-border economic transactions.  相似文献   
337.
26 Y chromosome short tandem repeat (STR) loci were amplified in a sample of 856 unrelated males from Bhutan, using two multiplex polymerase chain reaction (PCR) assays. The first multiplex is the Y-STR 20plex described by Butler et al. [J.M. Butler, R. Schoske, P.M. Vallone, M.C. Kline, A.J. Redd, M.F. Hammer, A novel multiplex for simultaneous amplification of 20 Y chromosome STR markers, Forensic Sci. Int. 129 (2002) 10-24], and the second is a novel (but overlapping) 14plex that targets six additional Y-STRs (DYS425, DYS434, DYS435, DYS436, DYS461, DYS462) and also amplifies the amelogenin locus. The 26-loci give a discriminating power of 0.9957, though even at this resolution one haplotype occurs 24 times. We identify novel alleles at five loci and microvariants at a further three, which were characterised by sequencing. Extended (11-locus) haplotypes for these samples have been submitted to the Y-STR Haplotype Reference Database (YHRD).  相似文献   
338.
339.
340.
van Praag HM 《危机》2004,25(2):80-85
Stress almost always precedes suicidality. Stress also is a harbinger of a variety of psychiatric disorders, most notably depression. Depression is a major precursor of suicidal behavior. Consequently, the question of whether stress is an epiphenomenon or a decisive factor in the causation of suicidality and (certain forms of) mood disorders is crucial. Certainty about this question can only be obtained when it can be demonstrated that stress phenomena may induce changes in brain functioning similar to the ones supposedly associated with suicidality and with (certain forms of) depression. Since the phenomenology of stress syndromes, as well as their emotional intensity, are highly variable, careful definition of the stress syndrome to be studied is a first requirement. In studies into the significance of stress in the occurrence of suicidality and depression, this degree of finesse has not been achieved. The major shortcomings have been discussed. These should be systematically addressed to provide research into the relation between stress and psychopathology with the necessary acuity.  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