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   365篇
  免费   12篇
各国政治   27篇
工人农民   28篇
世界政治   23篇
外交国际关系   18篇
法律   205篇
中国政治   2篇
政治理论   71篇
综合类   3篇
  2023年   5篇
  2022年   3篇
  2021年   1篇
  2020年   2篇
  2019年   7篇
  2018年   21篇
  2017年   20篇
  2016年   17篇
  2015年   13篇
  2014年   16篇
  2013年   44篇
  2012年   23篇
  2011年   10篇
  2010年   12篇
  2009年   16篇
  2008年   18篇
  2007年   15篇
  2006年   13篇
  2005年   9篇
  2004年   13篇
  2003年   11篇
  2002年   8篇
  2001年   11篇
  2000年   13篇
  1999年   6篇
  1998年   5篇
  1997年   1篇
  1996年   3篇
  1995年   2篇
  1994年   3篇
  1993年   5篇
  1992年   1篇
  1991年   2篇
  1990年   6篇
  1989年   3篇
  1987年   1篇
  1986年   1篇
  1985年   3篇
  1984年   1篇
  1981年   1篇
  1980年   2篇
  1979年   3篇
  1977年   1篇
  1974年   2篇
  1973年   1篇
  1970年   2篇
  1963年   1篇
排序方式: 共有377条查询结果,搜索用时 15 毫秒
91.
Efforts to set standards for artificial intelligence (AI) reveal striking patterns: technical experts hailing from geopolitical rivals, such as the United States and China, readily collaborate on technical AI standards within transnational standard-setting organizations, whereas governments are much less willing to collaborate on global ethical AI standards within international organizations. Whether competition or cooperation prevails can be explained by three variables: the actors that make up the membership of the standard-setting organization, the issues on which the organization's standard-setting efforts focus, and the “games” actors play when trying to set standards within a particular type of organization. A preliminary empirical analysis provides support for the contention that actors, issues, and games affect the prospects for cooperation on global AI standards. It matters because shared standards are vital for achieving truly global frameworks for the governance of AI. Such global frameworks, in turn, lower transaction costs and the probability that the world will witness the emergence of AI systems that threaten human rights and fundamental freedoms.  相似文献   
92.
A chimney built and operated according to the instructions is supposed to ensure that the combustion gases coming from the fireplace can escape safely. If the operational reliability is impaired, this presents a risk of acute poisoning. The report deals with a negligently caused carbon monoxide poisoning of a married couple as a consequence of improper installation of a cover of the chimney opening. Various causes of fatal poisoning due to defective exhaust systems are discussed in connection with the presented case report.  相似文献   
93.
One crucial element for the evolution of cooperation may be the sensitivity to others?? efforts and pay-offs in comparison with one??s own costs and gains. If an individual responds to a disadvantageous reward distribution, then it would likely increase its relative fitness compared with those who do not (Brosnan & de Waal, Nature 428:140, 2004). Recent experimental research indicates that sensitivity toward unequal reward distribution is not a uniquely human trait; non-human primates react to inequity if they witness a conspecific that obtains a more attractive reward for the same effort. However, primates are not the only species that cooperate and thus would benefit from inequity aversion. Canids also frequently cooperate with group members (e.g., wolves, wild dogs, etc.) or humans (domestic dogs), allowing for the possibility that they also are sensitive to the reward distribution. We report the findings of two studies of dogs?? responses to inequity and the social factors that mediate such responses. In the first study, we investigated whether domestic dogs showed a response to the inequity of rewards received for the same action in pairs of familiar dogs. We found that dogs showed significant behavioral differences when tested without food rewards when in the presence of a rewarded partner compared to the baseline and asocial control situations. This indicated that the presence of a rewarded partner matters (Range, Horn, Virányi, & Huber, Proc Natl Acad Sci USA 106(1):340?C345, 2009). In contrast to primates, dogs did not react to differences in the quality of food or effort. In the second study, we analyzed whether individual (motivational or personality) characteristics determined the response of each subject to unequal reward distributions or whether the subject??s responses depended on the specific relationship they had with its partner. We found that individual motivation and the quality of the relationship influenced the dogs?? performance in test conditions, but that these factors varied across the control and reward inequity conditions. Overall, our results suggest that inequity aversion in dogs is conditional on their and their partner??s rewards. Whether inequity aversion is based on the same mechanisms in both humans and non-human primates is still unclear.  相似文献   
94.
95.
96.
In this paper, the author revisits the emotive theory of value and argues that values are not entities but nothing other than linguistic fictions. Accordingly, valuations—i.e., valuing actions—can be defined as approving or disapproving attitudes of a subject to some object. In this perspective, values cannot be true or false: What we can do is just compare them with regard to strength. As a consequence, value judgments are to be understood as sentences which are used either to say that a subject s values an object o positively or negatively, or to express (evince) a valuation. The author then shows some relations between normative and evaluative discourses. First, he claims that norms as well as valuations are not true or false. Second, he argues that both may be explained or justified, even if the former are usually justified teleologically whereas the latter are explained referring back to the subject's background and life-style. Third, he notes that a legal order originates from the fact that valuations crystallize into norms. Finally, the author examines some further questions related to his analysis. In particular, he argues that the different realms of values, e.g., morals, aesthetics, politics, etc., do not correspond to different evaluative attitudes, but to different phenomena and diverse spheres of human life.  相似文献   
97.
Asia Europe Journal - Against the background of ever stronger linkages between the EU and China as well as their emphatically voiced objective to jointly shape the increasingly multi-polar world,...  相似文献   
98.
Traditional pollen preparation techniques provide clear residues for pollen identification; however, such methods are time-consuming, requiring repeated centrifugation, heating, and digestion with high-concentration hazardous chemicals. Tobacco leaves can effectively trap environmental pollen due to hairy surface and terpene-rich exudates. A new tobacco sample processing method was developed by using different extraction chemistry with surfactant. Marlboro Gold cigarettes were employed as model samples for method development. Parameters critical for pollen extraction, which include number of cigarette sticks used, extraction solution, and extraction temperature, were optimized. By using 1% dishwashing detergent to treat three cigarettes at room temperature, the improved method was able to recover sufficient pollen for microscopic analysis in three repeated centrifuge-washing steps and omit hazardous chemicals involved in traditional methods. We focused on the pollen of common ragweed (Ambrosia artemisiifolia), a plant native to North America, as an indicator to differentiate genuine and counterfeit U.S. brand cigarettes. Results from analyzing randomly purchased genuine (authenticated by forensic examination) and known counterfeit Marlboro Gold provided by law enforcement revealed that a significant amount (39%) of Ambrosia were consistently present in all genuine samples, while counterfeit contained none or only trace count. Similar results were found in other counterfeit U.S. brand cigarettes (all seized in the U.S.) involved in this study as well. Lack of Ambrosia in cigarette strongly indicates the product was not originated in the United States.  相似文献   
99.
In a certain amount of paternity investigations, only DNA from child and alleged father is analyzed, thus increasing the possibility of false paternity inclusions. The aim of this study was to determine how many wrong paternity inclusions could be detected in a rather small geographical area comparing empirical results from 336 children and 348 men (13-15 STRs were investigated per person). This comparison between each child and all unrelated men (i.e. all putative fathers from the other cases) with an especially designed computer program resulted in 116,004 man/child pairs. Less than three excluding STRs were found in 1666 child/unrelated man pairs (1.44% of the comparisons). At least one unrelated man with only two or less STR mismatches could be determined for 322 children (95.8% of all investigated children). In 26 comparisons no STR mismatches between a child and an unrelated man were detected, thus at least one and up to three "second father(s)" under 350 men could be found for 23 children, if the mother is excluded. Paternity probabilities between 95.475% and 99.996% were calculated. Our results underline the difficulties in motherless paternity cases using only STR analysis and advise great precaution in assigning verbal predicates such as "paternity proven" in those investigations.  相似文献   
100.
This paper presents an overview of the organisation and the results of the collaborative exercises (CE) of the European DNA Profiling (EDNAP) Group's mitochondrial DNA population database project (EMPOP). The aim of the collaborative exercises was to determine whether uniformity of mtDNA sequencing results could be achieved among different laboratories. These were asked to sequence either the complete mtDNA control region or the two hypervariable regions HVI (16024-16365) and HVII (73-340) from DNA extracts, buccal swabs or bloodstains, proceeding in accordance with the protocol and strategies used in each individual laboratory. The results of the collaborative exercises were employed to identify possible sources of errors that could arise during the analysis and interpretation of mtDNA profiles. These findings were taken as a basis to tentatively make suitable arrangements for the construction of a high quality mtDNA database. One hundred fifty mtDNA profiles were submitted to the evaluating laboratory, and disaccording profiles were classified into four groups corresponding to the source of error: clerical errors, sample mix-ups, contaminations and discrepancies with respect to the mtDNA nomenclature. Overall, 14 disaccording haplotypes (16 individual errors) were observed. The errors included 10 clerical errors, 3 interpretation problems, 2 cases of sample mix-up and 1 case of point heteroplasmic mixture, where the 2 sequencing reactions brought inconsistent base calls. This corresponds to an error rate of 10.7% in a virtual mtDNA database consisting of the collaborative exercise results. However, this estimate is still conservative compared to conclusions drawn by authors of meanwhile numerous publications critically reviewing published mtDNA population databases. Our results and earlier published concerns strongly emphasize the need for appropriate safety regulations when mtDNA profiles are compiled for database purposes in order to accomplish the high standard required for mtDNA databases that are used in the forensic context.  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