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91.
Numerous methods have been proposed to update input–output (I–O) tables. They rely on the assumption that the economic structure will not change significantly during the interpolation period. However, this assumption may not always hold, particularly for countries experiencing rapid development. This study attempts to combine forecasting with a matrix transformation technique (MTT) to provide a new perspective on updating I–O tables. Under the assumption that changes in the trend of an economic structure are statistically significant, the method extrapolates I–O tables by combining time series models with an MTT and proceeds with only the total value added during the target years. A simulation study and empirical analysis are conducted to compare the forecasting performance of the MTT to the Generalized RAS (GRAS) and Kuroda methods. The results show that the comprehensive performance of the MTT is better than the performance of the GRAS and Kuroda methods, as measured by the Standardized Total Percentage Error, Theil's U and Mean Absolute Percentage Error indices.  相似文献   
92.
This study examines financial analyst coverage for U.S. firms following an increase in foreign product market competition. To capture exogenous shocks to domestic firms' competitive environments, we exploit a quasi‐natural experiment from large import tariff reductions over the 1984 to 2005 period in the manufacturing sector. Using data for the years before and after large tariff reductions, our difference‐in‐differences analysis shows evidence of a significant decrease in analyst coverage for incumbent U.S. firms when they face greater entry threat from foreign competitors. We also find that analysts with less firm‐specific experience and less accurate prior‐period forecasts are more likely to stop following the domestic firm when foreign competition intensifies. Overall, the findings suggest that foreign product market competition from global trade liberalization is an important determinant of financial analysts' coverage decisions.  相似文献   
93.
邹浩  胡文 《物流技术》2020,(3):145-148
考虑物流管理专业实践教学的特性,从实践环节、创新与创业、管理机制、教学团队等方面构建了实践教学指标体系,并运用模糊综合评价法进行评价分析。研究结论表明,毕业实习、毕业论文、学科竞赛、创新与创业项目对物流管理专业实践教学的影响较大。  相似文献   
94.
Abstract

Objective: This study aimed to compare the cost-effectiveness of ramucirumab versus placebo for patients with hepatocellular carcinoma who progressed on sorafenib with α-fetoprotein concentrations (AFP) of at least 400?ng/ml in the United States.

Methods: A Markov model was constructed to assess the cost-effectiveness of ramucirumab. Health outcomes were measured as quality-adjusted life years (QALYs). With TreeAge software, the disease process was modeled as three health states: progression-free survival (PFS), progressive disease (PD), and death. Costs were extracted from the REACH-2 trial, and utility was derived from published literature. Incremental cost-effectiveness ratios (ICERs) were calculated to compare ramucirumab with placebo. Probabilistic sensitivity analyses were developed to examine the robustness of the results.

Results: In the base case analysis, ramucirumab therapy had a cost of $55,508.41 and generated 0.54 QALYs, while placebo therapy had a cost of $761.09 and generated 0.47 QALYs, leading to an additional $54,747.32 in costs and 0.07 QALYs. The ICER was $782,104.57 per QALY, which was much higher than the willingness-to-pay threshold of $100,000 per QALY. According to sensitivity analyses, the utility of PD in the two groups was the dominant parameter influencing the ICER.

Conclusion: Although ramucirumab was associated with prolonged survival for patients with advanced hepatocellular carcinoma who progressed on sorafenib treatment with an AFP of at least 400?ng/ml, it is not a cost-effective treatment from a United States payer perspective.  相似文献   
95.
Wen He  Ki Hoon Hong  Eliza Wu 《Abacus》2020,56(4):535-560
We investigate whether investor sentiment affects the relationships between accounting variables and contemporaneous stock returns. Using price-relevant accounting variables identified by Chen and Zhang (2007) and the investor sentiment index constructed by Baker and Wurgler (2006), we find that the value relevance of accounting variables is collectively lower in high sentiment periods than in low sentiment periods. More importantly, earnings yield appears to be more related to contemporaneous stock returns in high sentiment periods, while other accounting variables are more related to stock returns in low sentiment periods. The effect of investor sentiment on the value relevance of accounting information is stronger for firms that are more difficult to value and to arbitrage.  相似文献   
96.
Models of entry deterrence typically require that incumbents possess a cost advantage as a prerequisite for deterring entry. Potential entrants possess a cost advantage over incumbents, however, if input costs fall over time. This paper models the behavior of an incumbent and a potential entrant when the input cost falls over time and the firms have the option of buying or leasing the input. The model shows that if the future cost savings from new technology exceed the marginal transaction costs of leasing the current equipment, then leasing increases the incumbent's ability to deter entry. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
97.
经过改革开放后三十多年的发展,东莞市已经成长为典型的劳动密集型的制造业城市。城市在不断地发展,土地资源的有限性与社会经济发展的矛盾日益突出,使得东莞市的产业结构和土地利用结构与改革开放初期时的状态有明显不同。本文通过分析该市2005-2012年间产业结构和土地利用结构的数据及相关性,进一步理清两者之间的关系,并依此提出如何优化东莞市产业结构,提高土地利用效率的建议。  相似文献   
98.
利用Pro/E软件设计了一款多功能躺椅,实现坐、躺和攀爬相结合的功能。该装置采用整体设计、关键部位设计和细节设计的设计思路,利用Pro/E的骨架建模结合多功能躺椅自身结构的特点进行运动和受力分析。结果表明:该设计思路可以有效实现设计的一致性,设计的多功能躺椅既可以当椅子用,也可以转换为躺椅用来休息,同时又可以折叠成梯子来使用,从而达到一物三用的目的。  相似文献   
99.
外语磨蚀有七大影响因素,文章通过定量和定性分析,探究了存在于高职生中的英语磨蚀现象及其影响因素,阐述了高职英语教学减少和防止英语磨蚀的相应对策。  相似文献   
100.
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