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   71775篇
  免费   3294篇
各国政治   4545篇
工人农民   3021篇
世界政治   6279篇
外交国际关系   3864篇
法律   34770篇
中国共产党   11篇
中国政治   755篇
政治理论   20884篇
综合类   940篇
  2021年   415篇
  2020年   1178篇
  2019年   1536篇
  2018年   1748篇
  2017年   2041篇
  2016年   2244篇
  2015年   1857篇
  2014年   2121篇
  2013年   10577篇
  2012年   1733篇
  2011年   1828篇
  2010年   1876篇
  2009年   2117篇
  2008年   1863篇
  2007年   1863篇
  2006年   2065篇
  2005年   1935篇
  2004年   1792篇
  2003年   1576篇
  2002年   1667篇
  2001年   1839篇
  2000年   1587篇
  1999年   1389篇
  1998年   1146篇
  1997年   999篇
  1996年   958篇
  1995年   958篇
  1994年   956篇
  1993年   979篇
  1992年   1050篇
  1991年   1076篇
  1990年   1024篇
  1989年   1045篇
  1988年   1046篇
  1987年   1037篇
  1986年   1072篇
  1985年   1115篇
  1984年   991篇
  1983年   1009篇
  1982年   905篇
  1981年   853篇
  1980年   676篇
  1979年   744篇
  1978年   600篇
  1977年   536篇
  1976年   489篇
  1975年   422篇
  1974年   448篇
  1973年   440篇
  1972年   381篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Species identification of necrophagous insects found on a dead body is an essential key in applying medicolegal entomology to the estimation of postmortem interval (PMI). Due to limited morphological identification of insect evidence, several studies have identified species using molecular information such as DNA markers. While considerable cytochrome c oxidase subunit I (COI) gene sequence data of necrophagous fly species have been collected and annotated, those of necrophagous beetle species have not. Since necrophagous beetles such as Dermestes species have a larval period longer than that of flies, beetles are useful in even the late decomposition phase in estimating minimum PMI. To obtain the full-length COI gene sequences of six Dermestes species collected from South Korea, we designed primers for polymerase chain reaction amplification and sequencing. The obtained full COI nucleotide sequences were used for performing phylogenic analysis and comparison with previously reported sequences. The results demonstrated that the COI gene sequences could be used to identify forensically important Dermestes species in South Korea.  相似文献   
52.
We present results of our study on the stability of 4-chloromethcathinone (4-CMC) in authentic postmortem peripheral blood and vitreous humor samples. The stability of 4-CMC was determined in postmortem blood samples (for a period of 90 days) and vitreous humor (30 days) at three different temperatures: −15°C, +4°C, and + 23°C. The analyses were carried out using ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). In both materials, the lowest 4-CMC stability was demonstrated at room temperature. The blood samples stored in a freezer (−15°C) showed stability for the entire study period (90 days), while in the case of the vitreous humor sample stored at the same temperature the concentration of the substance decreased by 53% after 30 days. The study carried out in authentic postmortem blood and vitreous humor samples confirms the previous reports of 4-CMC instability in biological material. Authors suggest that the biological material should be stored frozen until analyses are carried out as soon as possible after collection of the material.  相似文献   
53.
The decision to go to war in Australia remains the prerogative of the Executive. The lack of parliamentary authorisation of perhaps the most significant decision a democracy can make has seen sustained, but unsuccessful, efforts to reform legislation. In the wake of the costly invasion and occupation of Iraq in 2003, repeated calls for legislative reform of Australia's war powers have failed to find traction amongst Coalition and Australian Labor Party (ALP) leadership. Lamenting the lack of transparency and accountability in the current system, those favouring legislative reform would see authorisation of combat missions placed in the hands of Parliament. However, given the lack of support from either of the major parties, any legislative reform remains unlikely. Given this impasse, this article argues that a compromise option, in the form of a new war-powers convention, may be a small step towards democratising the decision of going to war. While not legally binding, this constitutional convention would represent an agreement by the major parties that overseas combat operations will be properly debated in Parliament.  相似文献   
54.
55.
Sport's transformative potential is known to support marginalised children, to deal with traumatic experiences and instil positive values; yet hosting mega sporting events (MSEs) can have negative impacts. Drawing on participatory research with favela‐based children during the 2014 World Cup in Brazil, this article argues that MSEs bring a macro‐securitisation of urban life, which causes considerable harm. This paper also suggests that the inclusion of children's voices in advocacy debates can challenge top‐down securitisation and might allow MSEs to foster further positive social transformation. Therefore, juxtaposed with causing harm, macro‐securitisations can open opportunities for children to take action and have their voices heard.  相似文献   
56.
57.
Brazil's Movimento de Trabalhadores Sem Teto (MTST, Homeless Workers' Movement) has grown dramatically in recent years. This growth was partly provided for by the use of a large government housing programme, Minha Casa Minha Vida (MCMV, My House My Life), which allowed the MTST to construct housing for its members and swell its ranks with thousands of new members. Yet some have argued that the MCMV programme used by the MTST may compromise the autonomy of civil society organisations. This article, by contrast, argues that while the MCMV programme encouraged bureaucratic practices, it also helped to promote the cultural politics of the MTST.  相似文献   
58.
59.
This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source.  相似文献   
60.
This paper examines the power to prorogue (or suspend) Parliament following the 2019 prorogation controversy in the UK. We outline the legal basis of prerogative-based prorogation, survey its uses in the UK and other Westminster systems, and compare it with equivalent rules in other European parliamentary democracies. The comparative perspective highlights the outlier status of the UK among comparable European democracies. In the UK, the absence of explicit legal limits on the use of prorogation gives the executive exceptional scope to employ the power for political purposes to sidestep Parliament. We conclude by discussing the implications of these findings for current discussions about the desirability of reforming the UK’s prorogation rules and placing express legal limits on the executive’s power.  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