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   238篇
  免费   25篇
各国政治   16篇
工人农民   41篇
世界政治   15篇
外交国际关系   17篇
法律   131篇
中国政治   2篇
政治理论   41篇
  2023年   7篇
  2022年   2篇
  2021年   5篇
  2020年   12篇
  2019年   11篇
  2018年   15篇
  2017年   14篇
  2016年   22篇
  2015年   12篇
  2014年   12篇
  2013年   30篇
  2012年   14篇
  2011年   13篇
  2010年   6篇
  2009年   6篇
  2008年   11篇
  2007年   7篇
  2006年   7篇
  2005年   5篇
  2004年   8篇
  2003年   4篇
  2002年   5篇
  2001年   1篇
  1999年   2篇
  1997年   2篇
  1996年   4篇
  1995年   1篇
  1994年   2篇
  1993年   1篇
  1992年   2篇
  1991年   1篇
  1989年   1篇
  1987年   4篇
  1986年   2篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1981年   1篇
  1976年   1篇
  1975年   1篇
  1974年   2篇
  1973年   3篇
  1970年   1篇
排序方式: 共有263条查询结果,搜索用时 15 毫秒
41.
42.
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   
43.
Florida's innovative Law Enforcement Families Partnership (LEFP) was created to reduce and prevent officer‐involved domestic violence in the state. Administered by the Institute for Family Violence Studies at Florida State University and supported by the criminal justice and victim's advocacy communities, the LEFP is the first statewide project of its kind. It includes several components, the cornerstone of which is an online curriculum that teaches officers about the dynamics and consequences of domestic violence perpetrated by officers. This article describes the project and early data from the surveys attached to the curriculum.  相似文献   
44.
45.
Sex determination is one of the essential steps in personal identification of an individual from skeletal remains. Most elements of the skeleton have been subjected to discriminant function analysis for sex estimation, but little work has been done in terms of the patella. This paper proposes a new sex determination method from the patella using a novel automated feature extraction technique. A dataset of 228 patellae (95 females and 133 males) was amassed from the William M. Bass Donated Skeletal Collection from the University of Tennessee and was subjected to noninvasive high resolution computed tomography (CT). After the CT data were segmented, a set of features was automatically extracted, normalized, and ranked. The segmentation process with surface smoothing minimizes the noise from enthesophytes and ultimately allows our methods to distinguish variations in patellar morphology. These features include geometric features, moments, principal axes, and principal components. A feature vector of dimension 45 for each subject was then constructed. A set of statistical and supervised neural network classification methods were used to classify the sex of the patellar feature vectors. Nonlinear classifiers such as neural networks have been used in previous research to analyze several medical diagnosis problems, including quantitative tissue characterization and automated chromosome classification. In this paper, different classification methods were compared. Classification success ranged from 83.77% average classification rate using labels from a Fuzzy C-Means (FCM) clustering step, to 90.3% for linear discriminant classification (LDC). We obtained results of 96.02% and 93.51% training and testing classification rates, respectively, using feed-forward backpropagation neural networks (NN). These promising results using newly developed features and the application of nonlinear classifiers encourage the usage of these methods in forensic anthropology for identifying the sex of an individual from incomplete skeletons retaining at least one patella.  相似文献   
46.
In the absence of ongoing involvement in the communities that are the subjects of research, even well-intentioned researchers can develop questions that are not relevant to community needs, employ methods that hurt community members, or disseminate findings in ways that are inaccessible to those most affected. Recognizing these harms, a growing number of domestic violence (DV) researchers have embraced community-based participatory research (CBPR), an approach in which researchers and community members share power at every level of the research process, co-creating knowledge that can be applied to enhance community well-being. Despite growing interest in this approach, however, there are insufficient opportunities for interested researchers to learn how to actually engage in it, especially in the DV context. To remedy this gap, the authors of this paper collaborated to develop an online toolkit for emerging researchers interested in CPBR. This brief report frames the need for CBPR in DV research using short vignettes that come from our own research experience; introduces Power Through Partnerships: A CBPR Toolkit for Domestic Violence Researchers; and presents recommendations for developing, promoting, and disseminating future CBPR research. We chose to announce the development and availability of this toolkit in an academic journal in order to highlight its scholarly and practical relevance for researcher audiences who might be less familiar with the CBPR approach.  相似文献   
47.
I focus on evaluating Brazilian development and humanitarian cooperation in Haiti to answer how emerging providers such as Brazil are contributing to global development through cooperation. The paper establishes criteria for evaluation, arguing that global standards for aid effectiveness need to be expanded. I argue that when assessed on ownership, efficiency and sustainability, cooperation holds several advantages and limits, such as misplaced assumptions that Brazil’s approach is appropriate elsewhere. The discussion is rooted in the context of Haiti in order to underline how outcomes are not pre-determined, but rather depend on the model’s interaction with the partner context.  相似文献   
48.
This article focuses on the construction of “soldier” and “victim” by post-conflict programs in Sierra Leone. Focusing on the absence of individual testimonies and interviews that inform representations of women and girls post-conflict, this article demonstrates that the ideal of the female war victim has limited the ways in which female combatants are addressed by disarmament, demobilization, and reintegration (DDR) programs in Sierra Leone. It is argued that titles given to female soldiers such as “females associated with the war,” “dependents,” or “camp followers” reveal the reluctance of reintegration agencies to identify females who participated in war as soldiers. In addition, I argue that men and masculinity are securitized post-conflict while women—even when they act in highly securitized roles such as soldiers—are desecuritized and, in effect, de-emphasized in post-conflict policy making. The impact of this categorization has been that the reintegration process for men has been securitized, or emphasized as an essential element of the transition from war to peace. In contrast, the reintegration process for females has been deemed a social concern and has been moralized as a return to normal.  相似文献   
49.
Color determination of soil evidence is often done by visual comparison to soil color charts. A handheld spectrophotometer was tested with representative materials for its suitability for forensic soil characterization. Instrumental colorimetry provides accurate colorimetry with ~10-fold better precision than a soil color chart. The minimum sample size for accurate color determination was between 0.02 and 0.04 mg of fine soil for the specific instrument tested. Reporting colors in the L*a*b* space permits quantification of ΔE00, a measure of perceptible color difference, could enable objective quantification of small color differences and thresholds for forensic soil comparisons. A ΔE00 greater than ~ 3.5 to 6 likely indicates disparate soil sources in a forensic comparison, in the absence of confounding factors like sample alteration. Despite the superior precision of instrumental colorimetry, this approach is inappropriate for samples which are mottled at an inseparable scale, attached to a substrate, or too small for instrumental measurement.  相似文献   
50.
This article focuses on the degree of policy congruence, and by extension policy responsiveness, of U.S. federal‐ and state‐level GMO labeling laws from 2011–2016. Utilizing consumer survey data, evidence overwhelmingly demonstrates consumers prefer clear text‐based indication if food products contain genetically modified ingredients. However, the federal law adopted in 2016 mandates GMO labeling but with exceptions permitted to clear on‐package text labeling. The results of this study demonstrate that consumer preferences were not adequately represented at the federal level and were misaligned with state policy activities as captured in the aggregate outcome. State legislatures were actively proposing mandatory legislation with only a few cases of success, which did not adequately represent the wishes of the people. Given the misalignment and overall policy incongruence, the consequences of pending federal law are discussed in light of why the voices of the consumer choir were not heard by lawmakers.  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