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   5272篇
  免费   39篇
  国内免费   1篇
教育   3851篇
科学研究   317篇
各国文化   48篇
体育   683篇
综合类   4篇
文化理论   111篇
信息传播   298篇
  2024年   57篇
  2023年   58篇
  2022年   83篇
  2021年   128篇
  2020年   218篇
  2019年   332篇
  2018年   424篇
  2017年   427篇
  2016年   322篇
  2015年   214篇
  2014年   191篇
  2013年   1135篇
  2012年   201篇
  2011年   142篇
  2010年   128篇
  2009年   114篇
  2008年   96篇
  2007年   84篇
  2006年   86篇
  2005年   65篇
  2004年   50篇
  2003年   73篇
  2002年   44篇
  2001年   54篇
  2000年   36篇
  1999年   41篇
  1998年   36篇
  1997年   25篇
  1996年   36篇
  1995年   33篇
  1994年   29篇
  1993年   23篇
  1992年   18篇
  1991年   22篇
  1990年   26篇
  1989年   23篇
  1988年   23篇
  1987年   19篇
  1986年   14篇
  1985年   11篇
  1984年   13篇
  1982年   11篇
  1981年   13篇
  1980年   8篇
  1979年   11篇
  1978年   14篇
  1977年   9篇
  1976年   10篇
  1975年   10篇
  1974年   8篇
排序方式: 共有5312条查询结果,搜索用时 0 毫秒
101.
György Péteri 《Minerva》1996,34(4):367-380
Conclusions On the basis of these findings, I suggest that the structure and organisation of the field of Hungarian economics under state socialism should be described as a case of partitioned bureaucracy.9 The compromise between research economists and the political elite in the New Course era between 1953 and 195510 survived the post-1956 reaction in so far as political economy, with its predominantly legitimatory and ideological functions, remained partitioned from the other sectors in the field through the remainder of the state-socialist period. This secured considerable protection both for Marxist-Leninist political economy—which faced the destabilising effects of exposure to the findings of serious empirical research—and for the other sectors, which were professionally oriented and earnestly interested in the pursuit of unbiased empirical research, free from stifling agitprop interference. Our data concerning the reputational control of the field reflects only one, although very important, aspect of this partitioning. Another and much plainer aspect is that, from the early 1960s, the Agitation and Propaganda Department of the Central Committee no longer exercised control over the field, except in the political economy sector.The proposition about the mechanism paradigm should not be taken seriously as a statement of a Kuhnian type of intellectual organisation of Hungarian economics, with reform economics at its hard theoretical core. But it should certainly be taken seriously as a reflection of the sociopolitical structure which emerged and developed from the mid-1950s onwards. Neither the politicians nor the economists saw as necessary or even contemplated the integration of Hungarian economic research with Western mainstream economic thought. In exchange for the professional expertise and socio-economic intelligence necessary for the exercise of power, Hungary's state-socialist political class offered their economists relative autonomy and freedom from interference. The price the economists had to pay was partly to refrain from openly and systematically challenging the beliefs perpetuated by the political economy of socialism, and partly to accept in their research the paramountcy of policy orientation. But this burden they assumed willingly since it made them the only group within Hungary's academic intelligentsia—indeed, the only group in Hungarian society outside the political class—with the privilege of being coopted to the institutions with power over some restricted domains of policymaking. After 1989, especially under the conservative Antall government, this proved less than advantageous.11 Although the benevolence of many critics is open to question, it could greatly benefit the field if the economists' expulsion from contemporary politics went hand in hand with provision of the material, intellectual and institutional conditions for a new approach where a fundamentally scientific orientation is paramount.  相似文献   
102.
We describe the results of electromigration desalination of two soluble salt-contaminated Galician granites. The efficacy of electromigration, which had not been previously applied to granite, was assessed for two types of granite contaminated with a 20% NaCl solution and seawater. Desalination effectiveness was evaluated as follows: (1) analysis of anode and cathode ion content during testing; (2) analysis of ions at different distances from the electrodes after testing; (3) pH assessment of the stone surfaces; and (4) evaluation of colour changes. Results were very satisfactory; by the end of testing, chloride was reduced by almost 100% in both the NaCl and seawater contaminated samples. Sulfate reduction was also significant, despite this ion's lower mobility. The granite pH values remained close to neutral and colour changes were minimal. The difference in effectiveness of the process for the two types of stone was associated with their dissimilar pore structure.  相似文献   
103.
Digital libraries of scientific articles contain collections of digital objects that are usually described by bibliographic metadata records. These records can be acquired from different sources and be represented using several metadata standards. These metadata standards may be heterogeneous in both, content and structure. All of this implies that many records may be duplicated in the repository, thus affecting the quality of services, such as searching and browsing. In this article we present an approach that identifies duplicated bibliographic metadata records in an efficient and effective way. We propose similarity functions especially designed for the digital library domain and experimentally evaluate them. Our results show that the proposed functions improve the quality of metadata deduplication up to 188% compared to four different baselines. We also show that our approach achieves statistical equivalent results when compared to a state-of-the-art method for replica identification based on genetic programming, without the burden and cost of any training process.  相似文献   
104.
105.
Our work concerns the design of robust information retrieval environments that can successfully handle queries containing misspelled words. Our aim is to perform a comparative analysis of the efficacy of two possible strategies that can be adopted.  相似文献   
106.
For traditional industries it is a real challenge, not only to achieve a clear product differentiation, but also to provide adequate services in order to ensure value and customer fidelity.  相似文献   
107.
In this article, we draw on a survey conducted with elite upcoming lawyers from all around the world to shed new light on the ethical acceptability of file sharing practices. Although file sharing is typically illegal, our findings show that lawyers overwhelmingly perceive it as an acceptable social practice. The main criterion used by lawyers to decide on the ethical acceptability of file sharing is whether or not the infringer derives any monetary benefits from it. Further, our findings show that lawyers in the public sector (including judiciary and academia) are even more tolerant of online copyright infringement than those in the private sector. Interestingly, our data suggests that this is largely the result of self-selection: lawyers who lean more on the side of broad disclosure and social sharing tend to orient themselves toward the public sector. Implications for the current state of the debate on the reform of copyright law are discussed.  相似文献   
108.
109.
110.
To elucidate a higher rate of premature cardiovascular disease (CVD) in Asian Indian descendants (Roma) in Slovakia, we investigated frequency distribution, correlates and relationship of lipoprotein(a) [Lp(a)] to family CVD risk factors in Roma children and their Caucasian neighbors. The study sample consisted of 607 healthy children aged 7–18 years (55% Roma, 48% male) as part of the biracial (Roma–Caucasian) Slovak Lipid Community Study. Overall, frequency distribution data of Lp(a) were highly skewed to low concentrations, with markedly higher Lp(a) levels in Roma than in Caucasian children (median and range, mg/dL: 14.5; 0–159.2 vs 6.2; 0–112.3, P < 0.001), regardless of age and gender. Lp(a) was positively correlated with apo B (0.159, P = 0.004) in Roma, and LDL cholesterol (0.170, P = 0.005) in Caucasian children. In addition, daily income of the family was negatively related with Lp(a) in Roma (−0.134, P = 0.036) while positively in Caucasians (0.136, P = 0.047). For both race groups, no significant association was found between Lp(a) and age, body mass index, mean arterial pressure, smoking, and physical activity. Also, no significant relationships were examined between serum Lp(a) levels >30 mg/dL in children and family CVD risk factors, except for diabetes mellitus in parents of Caucasian origin (OR 4.46; 95%CI: 1.23–16.20). In a multivariate analysis, daily income, LDL cholesterol or apo B explained ~7% of the variance of Lp(a). This study suggests a significantly higher serum Lp(a) levels in Roma than in Caucasian children and a small effect, in general, of relevant CVD risk factors on the variation of Lp(a) levels in childhood.  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