全文获取类型
收费全文 | 68703篇 |
免费 | 3315篇 |
专业分类
各国政治 | 4594篇 |
工人农民 | 2869篇 |
世界政治 | 6111篇 |
外交国际关系 | 3892篇 |
法律 | 32037篇 |
中国共产党 | 10篇 |
中国政治 | 759篇 |
政治理论 | 20801篇 |
综合类 | 945篇 |
出版年
2023年 | 364篇 |
2021年 | 410篇 |
2020年 | 1171篇 |
2019年 | 1537篇 |
2018年 | 1672篇 |
2017年 | 1990篇 |
2016年 | 2190篇 |
2015年 | 1837篇 |
2014年 | 2126篇 |
2013年 | 10675篇 |
2012年 | 1591篇 |
2011年 | 1720篇 |
2010年 | 1828篇 |
2009年 | 2075篇 |
2008年 | 1740篇 |
2007年 | 1727篇 |
2006年 | 1910篇 |
2005年 | 1792篇 |
2004年 | 1712篇 |
2003年 | 1502篇 |
2002年 | 1539篇 |
2001年 | 1562篇 |
2000年 | 1365篇 |
1999年 | 1225篇 |
1998年 | 1109篇 |
1997年 | 989篇 |
1996年 | 958篇 |
1995年 | 921篇 |
1994年 | 933篇 |
1993年 | 945篇 |
1992年 | 951篇 |
1991年 | 982篇 |
1990年 | 928篇 |
1989年 | 982篇 |
1988年 | 958篇 |
1987年 | 987篇 |
1986年 | 949篇 |
1985年 | 1028篇 |
1984年 | 940篇 |
1983年 | 986篇 |
1982年 | 915篇 |
1981年 | 856篇 |
1980年 | 664篇 |
1979年 | 686篇 |
1978年 | 597篇 |
1977年 | 536篇 |
1976年 | 491篇 |
1975年 | 407篇 |
1974年 | 413篇 |
1973年 | 428篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
241.
242.
顶空固相微萃取气相色谱法快速检测尿液中氯胺酮 总被引:1,自引:1,他引:0
目的建立快速检测吸毒人员尿液中氯胺酮的顶空固相微萃取(HS/SPME)-GC/NPD的方法。方法样品瓶中加入尿液、氢氧化钠溶液、氯化钠,在95℃下加热搅拌,用聚二甲基硅氧烷SPME萃取头(100μm)顶空萃取20min,气相色谱氮磷检测器检测,外标法定量。结果尿液中氯胺酮浓度在0.2~20.0μg/ml范围内呈现线性关系(r2=0.9965),尿液添加1.0μg氯胺酮,平均回收率102.6%,RSD=3.39%(n=7),检测限1.13ng/ml(S/N=3)。结论建立的方法简单、快速、灵敏、准确,十分适合尿液等生物检材中氯胺酮的快速定性定量分析。 相似文献
243.
244.
245.
246.
DAVID P. FARRINGTON 《犯罪学》2003,41(2):221-225
The main aim of this paper is to advance knowledge and (especially) theories about developmental and life‐course criminology (DLC). First, I review the widely accepted DLC findings that all DLC theories have been designed to explain. Second, I review more contentious and unresolved empirical DLC issues that might present challenges to DLC theories. Third, I describe my own DLC theory and specify how it addresses key empirical and theoretical questions. Fourth, I summarize five important DLC theories, by Catalano and Hawkins, Sampson and Laub, Moffitt, LeBlanc, and Thornberry and Krohn. Fifth, I identify differences in assumptions and predictions between my theory and the other five theories. Finally, I recommend a detailed comparison of the key features of all DLC theories, of their answers to key empirical and theoretical questions, and of their predictions regarding key unresolved empirical DLC issues. 相似文献
247.
Research has indicated that school factors such as communal school organization and student bonding are predictive of school disorder, with greater communal organization and greater student bonding leading to less delinquency and victimization. Data from a nationally representative sample of 254 public, nonalternative, secondary schools were used to examine structural equation models representing hypothesized relationships among communal school organization, student bonding, and school disorder. The hypothesis that communally organized schools would have less disorder held true for teacher victimization and student delinquency, but not for student victimization. In addition, the hypothesis that the relationship between communal school organization and school disorder would be mediated by student bonding was supported for student delinquency, but not for teacher victimization. 相似文献
248.
Ernest L. Nickels 《Journal of criminal justice》2007,35(5):570
“Discretion” holds an unrivaled position at the core of the notional inventory employed in the study of criminal justice generally and policing particularly. Efforts to systematically define the term have been irregular and its status in the empirical literature is an ambiguous one. While spoken of as a quantitative aspect of the policing which influences behavior, measurement is rarely addressed. After sketching problems in present formulations, discretion is recast in terms of perceived job autonomy and an outline of two general constructs is contributed in hopes of renewing consideration of the potential relevance of the concept for police theory and research. 相似文献
249.
Laura K. Landolt 《Global Society》2007,21(3):393-414
To demonstrate that norms have independent causal power, constructivists de-emphasise material factors related to state interests and highlight social factors. Similarly, they conceptualise international organisations as autonomous from state influence, and focus on cases featuring non-state actors that stimulate a “tipping point” of norm diffusion among states in advance of state sponsorship. By contrast, this article utilises an historical materialist approach that admits both social and material data to examine the contrasting case of population control. It finds that US corporate foundations, eugenist demographers, feminist birth control activists and related NGOs conceptualised and promoted population control in the United States, at the United Nations, and across developing countries. However, the tipping point of norm diffusion occurred only after the United States publicly advocated population control. Indeed, material and social factors were inextricably bound together. 相似文献
250.