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   1070篇
  免费   71篇
各国政治   55篇
工人农民   40篇
世界政治   107篇
外交国际关系   130篇
法律   471篇
中国政治   4篇
政治理论   325篇
综合类   9篇
  2023年   10篇
  2021年   6篇
  2020年   28篇
  2019年   35篇
  2018年   35篇
  2017年   54篇
  2016年   62篇
  2015年   38篇
  2014年   40篇
  2013年   151篇
  2012年   35篇
  2011年   54篇
  2010年   38篇
  2009年   40篇
  2008年   38篇
  2007年   26篇
  2006年   35篇
  2005年   40篇
  2004年   42篇
  2003年   40篇
  2002年   28篇
  2001年   17篇
  2000年   26篇
  1999年   18篇
  1998年   17篇
  1997年   15篇
  1996年   11篇
  1995年   9篇
  1994年   7篇
  1993年   16篇
  1992年   8篇
  1991年   14篇
  1990年   14篇
  1989年   10篇
  1988年   6篇
  1987年   8篇
  1985年   11篇
  1984年   5篇
  1983年   7篇
  1982年   6篇
  1981年   3篇
  1980年   5篇
  1979年   3篇
  1978年   4篇
  1977年   4篇
  1976年   2篇
  1975年   5篇
  1974年   4篇
  1972年   3篇
  1970年   2篇
排序方式: 共有1141条查询结果,搜索用时 15 毫秒
181.
Synthetic cannabinoids are sprayed onto plant material and smoked for their marijuana‐like effects. Clandestine manufacturers modify synthetic cannabinoid structures by creating closely related analogs. Forensic laboratories are tasked with detection of these analog compounds, but targeted analytical methods are often thwarted by the structural modifications. Here, direct analysis in real time coupled to accurate mass time‐of‐flight mass spectrometry (DART‐TOF‐MS) in combination with liquid chromatography quadruple time‐of‐flight mass spectrometry (LC‐QTOF‐MS) are presented as a screening and nontargeted confirmation method, respectively. Methanol extracts of herbal material were run using both methods. Spectral data from four different herbal products were evaluated by comparing fragmentation pattern, accurate mass and retention time to available reference standards. JWH‐018, JWH‐019, AM2201, JWH‐122, 5F‐AKB48, AKB48‐N‐(4‐pentenyl) analog, UR144, and XLR11 were identified in the products. Results demonstrate that DART‐TOF‐MS affords a useful approach for rapid screening of herbal products for the presence and identification of synthetic cannabinoids.  相似文献   
182.
We examined potential predictors of initial court agreement and 1‐year relitigation in a sample of contested paternity cases involving unmarried parents coming to court to establish paternity, child support, and other issues. Cases participated in an RCT of a parent program and of a waiting period between establishment of paternity and court hearing. We controlled for RCT study factors and used baseline assessment data to predict likelihood of reaching full agreement in the initial court hearing and relitigation in the following year. Findings suggest that cases in which parents get along better outside of court are more likely to reach agreement and less likely to return to court. Additionally, particular parent demographics predict lower likelihood of reaching initial agreement (e.g., parents are non‐White, father earns below $10,000 yearly), more relitigation (e.g., parents are non‐White, mother earns above $10,000 yearly, father has children with others), and less relitigation (e.g., father earns above $10,000 yearly). Child demographics and most parent relationship characteristics did not predict outcomes. We discuss findings and offer suggestions for court interventions.  相似文献   
183.
184.
This article provides a review of the history of jihadi foreign fighters in Afghanistan over the last 30 years. It details the post-9/11 period and the invasion of Afghanistan by U.S. forces, focusing on the ethnic origin of the foreign fighters and how different groups engaged in different aspects of the conflict. Additionally, the piece explains that while the foreign fighters who came to fight alongside the Taliban in Afghanistan included, among others, Uzbekistanis (not Afghan Uzbeks), Turks, and Arabs, there was also a significant force of Pakistanis—of both Pashtun and Punjabi origins—that joined, bolstering the Taliban army.  相似文献   
185.
Editorial     
  相似文献   
186.
Editorial     
  相似文献   
187.
Editorial     
  相似文献   
188.
Suicide by asphyxiation using helium is the most widely-promoted method of "self-deliverance" by right-to-die advocates. However, little is known about persons committing such suicides or the circumstances and manner in which they are completed. Prior reports of suicides by asphyxiation involving helium were reviewed and deaths determined by the North Carolina Office of the Chief Medical Examiner to be helium-associated asphyxial suicides occurring between January 1, 2000 and December 31, 2008 were included in a new case series examined in this article. The 10 asphyxial suicides involving helium identified in North Carolina tended to occur almost exclusively in non-Hispanic, white men who were relatively young (M age = 41.1 T 11.6). In 6 of 10 cases, decedents suffered from significant psychiatric dysfunction; in 3 of these 6 cases, psychiatric disorders were present comorbidly with substance abuse. In none of these cases were decedents suffering from terminal illness. Most persons committing suicide with helium were free of terminal illness but suffered from psychiatric and/or substance use disorders.  相似文献   
189.
Data collection using the life event calendar method is growing, but reliability is not well established. We examine test–retest reliability of monthly self-reports of criminal behavior collected using a life event calendar from a random sample of minimum and medium security prisoners. Tabular analysis indicates substantial agreement between self-reports of drug dealing, property, and violent crime during a baseline interview (test) and a follow-up (retest) approximately 3 weeks later. Hierarchical analysis reveals that criminal activity reported during the initial test is strongly associated with responses given in the retest, and that the relationship varies only by the lag in days between the initial interview and the retest. Analysis of validity reveals that self-reported incarceration history is strongly predictive of official incarceration history although we were unable to address whether subjects could correctly identify the months they were incarcerated. African Americans and older subjects provide more valid responses but in practical terms the differences in validity are not large.  相似文献   
190.
Claims-made insurance policies often contain provisions regarding the treatment of the same, related, or interrelated acts or claims. Such language may affect the number of policy limits and retentions available as well as the timing of when multiple claims are deemed made. This article examines sample policy language as to the same, related, or interrelated acts or claims provisions as well as the disparate case law interpreting such provisions. The result is several principles to guide policyholders in the application of such language and to counter insurers’ efforts to unreasonably use such language to limit or deny coverage.  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