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   40514篇
  免费   525篇
  国内免费   1篇
财政金融   7144篇
工业经济   2449篇
计划管理   6085篇
经济学   9110篇
综合类   826篇
运输经济   178篇
旅游经济   433篇
贸易经济   8000篇
农业经济   1257篇
经济概况   4887篇
信息产业经济   45篇
邮电经济   626篇
  2021年   133篇
  2020年   247篇
  2019年   410篇
  2018年   2752篇
  2017年   2534篇
  2016年   1709篇
  2015年   373篇
  2014年   632篇
  2013年   2527篇
  2012年   1145篇
  2011年   2697篇
  2010年   2408篇
  2009年   2208篇
  2008年   2186篇
  2007年   2457篇
  2006年   636篇
  2005年   855篇
  2004年   991篇
  2003年   1036篇
  2002年   762篇
  2001年   510篇
  2000年   507篇
  1999年   437篇
  1998年   420篇
  1997年   416篇
  1996年   422篇
  1995年   358篇
  1994年   367篇
  1993年   400篇
  1992年   408篇
  1991年   401篇
  1990年   329篇
  1989年   301篇
  1988年   291篇
  1987年   302篇
  1986年   323篇
  1985年   468篇
  1984年   435篇
  1983年   400篇
  1982年   376篇
  1981年   346篇
  1980年   390篇
  1979年   318篇
  1978年   270篇
  1977年   256篇
  1976年   198篇
  1975年   242篇
  1974年   193篇
  1973年   188篇
  1972年   133篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
Without guaranteed compensation, granted by the German Renewable Energy Sources Act (Erneuerbare Energien Gesetz/EEG), biogas plants compete with all other plant types on the market for electrical energy. However, exchange-based electricity products do not currently permit an economically viable operation of biogas plants owing to their cost situation.  相似文献   
12.
13.
Do local partners' network attributes affect the survival of high-tech international joint ventures (IJV)? How does the effect of network attributes vary in different subnational institutional environments? While the classic economic explanation for IJV formation and subsequent performance draws from the resource-based view (RBV), we add the relational dimension to explain that IJV survival may be affected by local partners’ relation-specific assets within the local network. We test the effect of the local partners’ network attributes as calculated by UCINET (centrality, network status, and structural hole position) on IJV survival. We additionally assert that this relationship is moderated by subnational institutional heterogeneity. Using our sample of 125 IJV dyadic pairs of US multinational enterprises (MNEs) operating in high-tech industries and their local partners in China, we find partial support for our claims.  相似文献   
14.
15.
We explore the innovation performance benefits of alliances for spin-off firms, in particular spin-offs either from other firms or from public research organizations. During the early years of the emerging combinatorial chemistry industry, the industry on which our empirical analysis focuses, spin-offs engaged in alliances with large and established partners, partners of similar type and size, and with public research organizations, often for different reasons. We seek to understand to what extent alliances of spin-offs with other firms (either large- or small- and medium-sized firms) affected their innovation performance and also how this performance may have been affected by their corporate or public research background. We find evidence that in general alliances of spin-offs with other firms, in particular alliances with large firms, increased their innovation performance. Corporate spin-offs that formed alliances with other firms outperformed public research spin-offs with such alliances. This suggests that, in terms of their innovation performance, corporate spin-offs that engaged in alliances with other firms seemed to have benefitted from their prior corporate background. Interestingly, it turns out that the negative impact of alliances on the innovation performance of public research spin-offs was largely affected by their alliances with small- and medium-sized firms.  相似文献   
16.
During patent litigation, pay‐for‐delay (P4D) deals involve a payment from a patent holder of a branded drug to a generic drug manufacturer to delay entry and withdraw the patent challenge. In return for staying out of the market, the generic firm receives a payment, and/or an authorized licensed entry at a later date, but before the patent expiration. We examine why such deals are stable when there are multiple potential entrants. We combine the first‐mover advantage for the first generic with the ability of the branded manufacturer to launch an authorized generic (AG) to show when P4D deals are an equilibrium outcome. We further show that limiting a branded firm's ability to launch an AG before entry by a successful challenger will deter such deals. However, removing exclusivity period for the first generic challenger will not.  相似文献   
17.
Forward guidance can be provided as an unconditional promise, i.e. commitment to a specific low policy rate. Alternatively, the promise may include an escape clause, i.e. a condition defining the state of the economy under which the central bank would not keep such a low rate and, instead, it would revert to setting policy under discretion. The escape clause can be expressed as a threshold in terms of a specific variable. The present paper shows that, when such a threshold is expressed in terms of an endogenous variable (e.g. output, inflation), there are cases where it becomes impossible for the central bank to act in a way that is consistent with its promise. Consistency imposes limits on the policy rate that can be set since reverting immediately to the optimal discretionary rate can be incompatible with exceeding the threshold.  相似文献   
18.
Decisions in Economics and Finance - This paper sets out to explore the nexus between cryptocurrencies connected to cannabis production and the three highest capitalization digital currencies....  相似文献   
19.
20.
Review of Accounting Studies - Abstract We examine whether broad-based public engagement by institutional investors influences the behavior of portfolio firms. We investigate this question in the...  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