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   3743篇
  免费   121篇
  国内免费   82篇
财政金融   548篇
工业经济   143篇
计划管理   774篇
经济学   630篇
综合类   635篇
运输经济   19篇
旅游经济   49篇
贸易经济   447篇
农业经济   221篇
经济概况   480篇
  2024年   14篇
  2023年   49篇
  2022年   41篇
  2021年   84篇
  2020年   114篇
  2019年   90篇
  2018年   63篇
  2017年   72篇
  2016年   90篇
  2015年   124篇
  2014年   291篇
  2013年   281篇
  2012年   307篇
  2011年   367篇
  2010年   299篇
  2009年   208篇
  2008年   246篇
  2007年   254篇
  2006年   258篇
  2005年   201篇
  2004年   118篇
  2003年   113篇
  2002年   68篇
  2001年   49篇
  2000年   49篇
  1999年   28篇
  1998年   12篇
  1997年   15篇
  1996年   11篇
  1995年   5篇
  1994年   6篇
  1993年   8篇
  1992年   2篇
  1991年   3篇
  1990年   1篇
  1989年   1篇
  1987年   1篇
  1984年   2篇
  1983年   1篇
排序方式: 共有3946条查询结果,搜索用时 31 毫秒
101.
Open source software (OSS) projects represent a new paradigm of software creation and development based on hundreds or even thousands of developers and users organised in the form of a virtual community. The success of an OSS project is closely linked to the successful organisation and development of the virtual community of support group. This paper reviews different fields and research topics related to the OSS communities such as collective intelligence, the structure of OSS communities, their success, communities as virtual organisations, motivation, shared knowledge, innovation and learning. The main challenges, results obtained, and the knowledge areas are detailed for each topic.  相似文献   
102.
Background and aims: IDegLira, a fixed ratio combination of insulin degludec and glucagon-like peptide-1 receptor agonist liraglutide, utilizes the complementary mechanisms of action of these two agents to improve glycemic control with low risk of hypoglycemia and avoidance of weight gain. The aim of the present analysis was to assess the long-term cost-effectiveness of IDegLira vs liraglutide added to basal insulin, for patients with type 2 diabetes not achieving glycemic control on basal insulin in the US setting.

Methods: Projections of lifetime costs and clinical outcomes were made using the IMS CORE Diabetes Model. Treatment effect data for patients receiving IDegLira and liraglutide added to basal insulin were modeled based on the outcomes of a published indirect comparison, as no head-to-head clinical trial data is currently available. Costs were accounted in 2015?US dollars ($) from a healthcare payer perspective.

Results: IDegLira was associated with small improvements in quality-adjusted life expectancy compared with liraglutide added to basal insulin (8.94 vs 8.91 discounted quality-adjusted life years [QALYs]). The key driver of improved clinical outcomes was the greater reduction in glycated hemoglobin associated with IDegLira. IDegLira was associated with mean costs savings of $17,687 over patient lifetimes vs liraglutide added to basal insulin, resulting from lower treatment costs and cost savings as a result of complications avoided.

Conclusions: The present long-term modeling analysis found that IDegLira was dominant vs liraglutide added to basal insulin for patients with type 2 diabetes failing to achieve glycemic control on basal insulin in the US, improving clinical outcomes and reducing direct costs.  相似文献   
103.
This paper examines the effectiveness of target rate guidance in open market operation by the central bank in China (PBOC). We find that target rate change in open market operation is effective in adjusting the short-term Treasury rates. The target rate changing direction is more effective than the target rate changing level. There is no significant asymmetry in the effectiveness between the target rate increase and target rate decrease. We also document that the effectiveness of the target rate is conditional on liquidity operation of the same direction, especially when they both aim to loosen the monetary policy. Furthermore, consecutive operations with higher intensity appear to be more effective in adjusting the market interest rate.  相似文献   
104.
针对目前我国建筑材料的发展现状,论述了节约型社会发展新型节能建材的必要性,以及新型墙体材料、保温隔热材料、防水密封材料、装饰装修材料的发展现状及趋势,发展新型节能建筑材料对于落实科学发展观和构建资源节约型社会具有的重要现实意义。  相似文献   
105.
We examine whether informed trading around earnings announcements drives mutual fund performance. The measure is motivated by prior studies arguing that a mutual fund is skilled if it buys stocks with subsequent high earnings announcement returns. We find that this measure predicts future mutual fund returns. On average, after adjusting for Carhart’s four risk factors, the top decile of mutual funds outperforms the bottom decile by 44 basis points per quarter. By decomposing fund alphas into two components in their relations to earnings, we find that this measure is only associated with earnings-related fund alphas. This measure can also be used to predict stock returns at future earnings announcements.  相似文献   
106.
论文以有效分配、促进竞争、实现经济价值为目标,建立了公开升价拍卖+密封拍卖的两阶段牌照拍卖模型,证明了其有效性和最优性。并以北京市为例讨论了牌照数量的确定、进入密封拍卖阶段的时机和牌照的流通等实际问题。这些讨论将有利于拍卖机制在现实中的操作实施。  相似文献   
107.
Is there a link between capital controls and monetary policy autonomy in a country with a floating currency? Shocks to capital flows into a small open economy lead to volatility in asset prices and credit supply. To lessen the impact of capital flows on financial instability, a central bank finds it optimal to use the domestic interest rate to “manage” the capital account. Capital account restrictions affect the behavior of optimal monetary policy following shocks to the foreign interest rate. Capital controls allow optimal monetary policy to focus less on the foreign interest rate and more on domestic variables.  相似文献   
108.
In the past few decades many countries have increased the presence of various forms of private sector involvement in airport ownership and management. This paper focuses on the financial performance of Italian airport companies. We present empirical evidence separately for two groups where public or private management majority prevails. The main findings indicate that companies with a private majority outperform the others in terms of financial indicators that are related to operating income.  相似文献   
109.
Despite data limitations, an attempt is made to find out if a GDP nowcasting model can provide reliable forecasts for a small open economy. Two competing Bayesian vector autoregressive models are tested rigorously to obtain the optimal model by minimizing in-sample forecasting errors. The main finding of this study is that GDP nowcasting can produce reliable results for a small open economy despite the unavailability of sufficient data sets and the lack of high frequency indicators.  相似文献   
110.
为解决绵阳卷烟厂卷包生产过程中存在的设备自控关联性差、连锁方式难以改变、分散的设备与生产运行难以监控、生产管理模式难以满足柔性化生产等问题,引进了卷包集控系统,并对该系统的三层网络结构进行了规划设计、对比分析。通过改变三个网络层次之间的连接方式、网络拓扑结构,使卷接包生产因集控系统网络故障引起的停机时间降到最低。应用效果表明,改进后的网络结构有利于缩小网络规模,控制网络风险,保证数据交换,避免I/O整体失控,有效提高了通信网络的安全性和稳定性及网络资源的利用率。  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