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   69篇
  免费   5篇
各国政治   2篇
工人农民   3篇
世界政治   1篇
外交国际关系   2篇
法律   53篇
中国共产党   1篇
政治理论   11篇
综合类   1篇
  2023年   1篇
  2022年   1篇
  2021年   1篇
  2020年   4篇
  2019年   1篇
  2018年   4篇
  2017年   8篇
  2016年   4篇
  2015年   2篇
  2014年   5篇
  2013年   11篇
  2012年   10篇
  2011年   4篇
  2010年   3篇
  2009年   1篇
  2008年   1篇
  2007年   3篇
  2006年   1篇
  2004年   2篇
  2003年   2篇
  2002年   1篇
  2001年   1篇
  1999年   2篇
  1995年   1篇
排序方式: 共有74条查询结果,搜索用时 15 毫秒
1.
Lophophora is a member of the Cactaceae family, which contains two species: Lophophora williamsii and L. diffusa. Lophophora williamsii is an illegal plant containing mescaline, a hallucinogenic alkaloid. In this study, a novel method based on a single nucleotide polymorphism (SNP) assay was developed for identifying L. williamsii; this assay reliably detects SNPs within chloroplast DNA (rbcL, matK, and trnL-trnF IGS) and was validated for identifying Lophophora and L. williamsii simultaneously. The chloroplast DNA sequences from four L. williamsii and three L. diffusa plants were obtained and compared using DNA sequence data from approximately 300 other Cactaceae species available in GenBank. From this sequence data, a total of seven SNPs were determined to be suitable for identifying L. williamsii. A multiplex assay was constructed using the ABI PRISM® SNaPshot™ Multiplex Kit (Applied Biosystems, Forster City, CA) to analyze species-specific SNPs. Using this multiplex assay, we clearly distinguished the Lophophora among 19 species in the Cactaceae family. Additionally, L. williamsii was distinguished from L. diffusa. These results suggest that the newly developed assay may help resolve crimes related to illegal distribution and use. This multiplex assay will be useful for the genetic identification of L. williamsii and can complement conventional methods of detecting mescaline.  相似文献   
2.
广州公民政治参与状况调查   总被引:7,自引:0,他引:7  
公民政治参与是衡量政治文明发展程度的重要标志。调查显示当前广州公民政治参与呈现引人关注的若干基本特点 :党和政府的基层组织、职能部门以及领导人是党群、政群沟通的第一线力量 ;报纸、电视等成为公民政治参与的主流渠道 ,互联网在参与中的作用加强 ;国有和三资企业中的中高级管理人员、个体经营者成为政治生活的一支重要力量 ;选举机制的不完善和沟通渠道的不畅通阻碍公民政治参与的热情 ;多数公民倾向于以正式途径和理智行动解决纠纷 ,但对激烈手段的认同率有所上升 ;必须重视由利益受损、失业压力及腐败问题造成的群众性事件  相似文献   
3.
Existing theories on real exchange rates predict a significant undervaluation of the Korean won (KRW) in the early and mid-1990s. The paper demonstrates why this expectation did not materialize and instead an unprecedentedly large degree of overvaluation took place. Focusing on three variables, namely, financial repression, devaluation pass-through, and policy exhibitionism, the paper examines how the unraveling of the developmental state eventually gave rise to the 1990s’ overvaluation. It argues that the policy exhibitionism of the new civilian government amplified the influence of Chaebol on monetary policies, which in turn created a strong appreciative force to KRW. It also contends that the increasing exchange rate pass-through onto the prices of imported intermediate goods explains why Chaebol did not desire to tame the excessive appreciative trend despite its detrimental effect on their exports. The paper offers policy implications for other state-led, emerging economies.  相似文献   
4.
U.S. immigration control is typically understood in terms of enforcement practices undertaken by federal officers guided by legislation and court decisions. While legislation and court opinions are important components of the immigration control apparatus, they do not adequately account for immigration control ‘on the ground.’ To explore this problem, we advance the concept of paralegality, the practices and operations that constitute a dynamic system of actions and relationships that are not simply linear applications of legislation or judicial decisions but may in fact extend or counter these texts. We illustrate the importance of paralegality by reconstructing the evolution of the §287(g) and Secure Communities programs, both of which have shape-shifted dramatically since their inception. Our account of immigration control highlights the problem practice poses for law, proposes a theoretical alternative to textual-law-centric research on immigration and law enforcement, and contributes to scholarship on everyday citizenship.  相似文献   
5.
Impurity profiling and classification of seized methamphetamine may play an important role in the interpretation of analytical results, the determination of the synthetic method employed, and the criminal investigations of drug traffic routes. Our study is focused on classifying seized methamphetamine samples according to the groups sorted by the types and quantities of impurities present in illicit methamphetamine samples. The samples (100 mg) were dissolved in 2 mL of potassium phosphate buffer (pH 7.0), extracted with 200 μL of ethyl acetate under basic condition, and then analyzed by gas chromatography-mass spectrometry (GC–MS) with a DB-1 capillary column (30 m × 0.25 mm i.d., 0.25 μm). Five impurities are used as criteria for the classification of seized methamphetamine samples by Emde and Nagai method. A total of fifty-two samples of seized methamphetamine were analyzed by GC–MS and classified by five organic impurities, and then sorted into four groups, which are Nagai type, Emde Type, Undetermined I type, and Undetermined II type.  相似文献   
6.
7.
Predispositions and orientation toward cooperation or competition with other jurisdictions can play a critical role in implementing regional collaboration. By examining collaboration at the micro level, this article investigates how individual factors, including perceptions of cooperation and competition, as well as institutional and environmental factors, are related to regional collaboration. In particular, the authors assert that competitive motivation may support the emergence of regional governance mechanisms. This article explores the relationships between competitive/cooperative motivations and interlocal collaboration networks based on a network survey conducted in the Orlando, Florida, metropolitan area. The authors apply a quadratic assignment procedure regression analysis to examine how dyadic conceptual ties of cooperation and competition, along with the effect of community characteristics, affect policy network structures for economic development. By comparing estimated coefficients with sampling distributions of coefficients from all of the permuted data sets, the regression results indicate the influences of perceived competition/cooperation on the network exchange.  相似文献   
8.
Lip prints are thought to have the ability to distinguish individuals and, hence, have a potential use in human identification purposes. However, questions remain regarding their utility for sex determination. This study aimed to classify lip prints for different individuals in a Portuguese population and to determine whether sex differences exist. Lip prints of 25 females and 25 males were obtained using dark-colored lipstick and cellophane tape. Lip prints were analyzed using a magnifying lens and classified according to the Suzuki and Tsuchihashi classification. A Type II pattern was found to be most common. A comparison of lip-print patterns between males and females showed results with a statistically significant difference: Type III pattern was most common in males, and a Type II pattern in females. This study corroborates the hypothesis that lip prints are able to distinguish individuals and may be useful in sex determination.  相似文献   
9.
Palatal rugae have been related with specific racial groups and are said to be useful in sex discrimination. This work aimed to characterize the palatal rugae patterns in a Portuguese population. Fifty plaster casts were examined for first and third rugae shape evaluation; shape, frequency, and association with sex were studied. In females, the most prevalent first rugae were the straight type on the right and the curve type on the left; in males, the straight type was the most prevalent on both sides. The most frequent third rugae type was sinuous on both sides, in both sexes. No significant sexual dimorphism in rugae shape was found (p > 0.05). When comparing these results with those from other investigations, it was clear that a particular rugae pattern could be established for different ethnic groups. However, the small sample size justifies further work in larger samples to validate these findings.  相似文献   
10.
A sensitive analytical method was developed for the quantitative determination of tetrodotoxin (TTX), a powerful sodium channel blocker, in human postmortem whole blood. The sample mixture was cleaned up using cation exchange SPE catridge after protein precipitation by methanol and then separated on a PC-HILIC (phosphorylcholine hydrophilic interaction liquid chromatography) column (150 mm × 2.0mm i.d., 5 μm) using a isocratic elution of 1% acetic acid and acetonitrile. The identification of TTX was performed on tandem mass spectrometry with electrospray ionization interface in positive ion mode. The retention time of voglibose (internal standard) and TTX was 5.1 and 6.0 min, respectively. TTX and internal standard (voglibose) were monitored and quantitated using the ion transitions: the respective precursor to product ion combinations, m/z 320/302 for TTX and m/z 268/92 for voglibose in the multiple reaction monitoring (MRM) mode. The recovery of TTX and voglibose was 61.4% and 62.8%, respectively and the good accuracy (97.7-103.9%), linearity (2-1200 ng/mL) and reproducibility were shown in this method. The limit of detection and limit of quantification were 0.32 ng/mL and 1.08 ng/mL, respectively. This method was applied in the case of three fishermen who were poisoned (including one death) by unknown fish on their boat in October 2010. In this case, the levels of TTX were 27.2, 30.0 and 29.7 ng/mL in heart blood, peripheral blood and serum of a victim, were 3.1 and 12.1 ng/mL in peripheral blood and 3.9 and 12.8 ng/mL in serum of two survivors, respectively.  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