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   9832篇
  免费   223篇
各国政治   644篇
工人农民   254篇
世界政治   581篇
外交国际关系   381篇
法律   6283篇
中国共产党   8篇
中国政治   49篇
政治理论   1748篇
综合类   107篇
  2020年   111篇
  2019年   141篇
  2018年   240篇
  2017年   232篇
  2016年   278篇
  2015年   203篇
  2014年   192篇
  2013年   981篇
  2012年   282篇
  2011年   264篇
  2010年   220篇
  2009年   246篇
  2008年   311篇
  2007年   312篇
  2006年   329篇
  2005年   223篇
  2004年   245篇
  2003年   228篇
  2002年   237篇
  2001年   419篇
  2000年   376篇
  1999年   300篇
  1998年   121篇
  1997年   110篇
  1996年   86篇
  1995年   89篇
  1994年   99篇
  1993年   86篇
  1992年   181篇
  1991年   199篇
  1990年   202篇
  1989年   203篇
  1988年   181篇
  1987年   169篇
  1986年   184篇
  1985年   151篇
  1984年   133篇
  1983年   144篇
  1982年   91篇
  1981年   91篇
  1980年   61篇
  1979年   129篇
  1978年   75篇
  1977年   63篇
  1976年   57篇
  1975年   67篇
  1974年   82篇
  1973年   80篇
  1972年   69篇
  1971年   62篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
901.
902.
Information sharing research has largely focused on capturing operational practices related to the exchange of information. A noticeable shortcoming of this developing literature is the lack of scholarly attention focused specifically on analytic personnel. The present study employs semi-structured interviews with 23 personnel that comprise the analytic unit within a regional fusion center located in a large metropolitan area in the United States. Findings indicate that there is significant ambiguity surrounding the organizational and geographic audiences to which intelligence products should be tailored. Moreover, it appears information sharing is sparse and reliant upon personal relationships between analysts and external organizations. Lastly, analysts do not receive feedback pertaining to the content and effectiveness of intelligence products created. These findings may be generalized to other analytical organizations whose primary goal is to gather, analyze and disseminate intelligence. Action steps for policymakers are provided.  相似文献   
903.
There are a number of forensic cases in which the identification of the epithelial cell type from which DNA originated would provide important probative evidence. This study aimed to develop a technique using histological staining of fixed cells to distinguish between skin, buccal and vaginal epithelium. First, 11 different stains were screened on formalin-fixed, wax-embedded cells from five women. Samples were analysed qualitatively by examining staining patterns (colour) and morphology (absence or presence of nuclei). Three of the staining methods – Dane's, Csaba's and Ayoub-Shklar – were successful in distinguishing skin epithelial cells from buccal and vaginal. Second, cells were smeared directly onto slides, fixed with one of five fixatives and stained with one of the three stains mentioned above. Methanol fixation, coupled with the Dane's staining method, specific to keratin, was the only technique that distinguished between all three cell types. Skin cells stained magenta, red and orange and lacked nuclei; buccal cells stained predominantly orange–pink with red nuclei; while vaginal cells stained bright orange with orange nuclei and a blue extracellular hue. This staining pattern in vaginal cells was consistent in samples collected from 50 women aged between 18 and 67. Identification of cell type from unlabelled micrographs by 10 trained observers showed a mean success rate of 95%. The results of this study demonstrate that histological staining may provide forensic scientists with a technique for distinguishing between skin, buccal and vaginal epithelial cells and thus would enable more conclusive analyses when investigating sexual assault cases.  相似文献   
904.
No consensus yet exists on how to handle incidental findings (IFs) in human subjects research. Yet empirical studies document IFs in a wide range of research studies, where IFs are findings beyond the aims of the study that are of potential health or reproductive importance to the individual research participant. This paper reports recommendations of a two-year project group funded by NIH to study how to manage IFs in genetic and genomic research, as well as imaging research. We conclude that researchers have an obligation to address the possibility of discovering IFs in their protocol and communications with the IRB, and in their consent forms and communications with research participants. Researchers should establish a pathway for handling IFs and communicate that to the IRB and research participants. We recommend a pathway and categorize IFs into those that must be disclosed to research participants, those that may be disclosed, and those that should not be disclosed.  相似文献   
905.
906.
907.
Allele frequencies for 16 STR loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, FGA, and SE33) were calculated for a sample of 300 unrelated individuals from Greece. No deviations from Hardy–Weinberg equilibrium were observed for all loci. The combined power of discrimination (PD) and the combined power of exclusion (PE) for the 16 tested STR loci were 0.999999999 and 0.999999816, respectively. Population comparisons were carried out and low genetic distances were found between our data and those previously published for other neighbouring European populations.  相似文献   
908.
The diagnosis of posttraumatic stress disorder (PTSD) sometimes is raised in compensation claims, in tort settings, and in other medical–legal settings. Accordingly, health-care and legal professionals working in these areas need to be familiar with the current findings and controversies concerning the disorder. The purpose of this article is twofold. First, we review the most important findings concerning the clinical features, etiology, and treatment of PTSD. Second, we examine six major controversies concerning the disorder that are relevant to psychologists and other medical–legal practitioners: (a) the issue of what qualifies as a traumatic stressor, (b) the question of whether traumatic stress causes brain damage, (c) the validity of the concept of delayed-onset PTSD, (d) the recovered memory controversy, (e) the question of whether PTSD can arise when the person has no memory of the trauma (e.g., due to concussion), and (f) issues concerning PTSD malingering. Throughout this article we offer recommendations for psychological and other medical–legal practice in relation to the evaluation of PTSD claims.  相似文献   
909.
Zusammenfassung Seit einem Jahr liegen die thematische Strategie für den Bodenschutz und der Entwurf der Bodenrahmenrichtlinie vor, mit denen die Europ?ische Kommission das europ?ische Umweltrecht komplettieren und einen nachhaltigen Umgang mit den Bodenressourcen erreichen will. Jahrzehnte vorher hatten schon die Welt-Boden-Charta und die Europ?ische Bodencharta eine nachhaltige Bodennutzung gefordert, um der anhaltenden Bodendegradation Einhalt zu gebieten. Vor 15 Jahren hatte die Weltgemeinschaft die Rio-Deklaration über Umwelt und Entwicklung und einen Aktionsplan für diese Deklaration, mit denen nachhaltige Entwicklung, nachhaltige Ressourcennutzung und nachhaltiger Bodenschutz umgesetzt werden sollen, vereinbart. Der Beitrag stellt die Strategie, die Rahmenrichtlinie und den Diskurs zwischen den am Entscheidungsprozess beteiligten Organen und Interessenvertretungen von Landwirtschaft und Industrie, der noch im Gange ist, dar. Auch werden einige Schlüsselthemen der Weiterentwicklung des Bodenschutzes, l?sungsbedürftige theoretische Fragen, die im Hintergrund der Auseinandersetzungen stehen, skizziert.  相似文献   
910.
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