全文获取类型
收费全文 | 29829篇 |
免费 | 354篇 |
专业分类
财政金融 | 5046篇 |
工业经济 | 1665篇 |
计划管理 | 4774篇 |
经济学 | 6651篇 |
综合类 | 567篇 |
运输经济 | 74篇 |
旅游经济 | 217篇 |
贸易经济 | 6608篇 |
农业经济 | 600篇 |
经济概况 | 3276篇 |
信息产业经济 | 44篇 |
邮电经济 | 661篇 |
出版年
2020年 | 133篇 |
2019年 | 203篇 |
2018年 | 2491篇 |
2017年 | 2261篇 |
2016年 | 1467篇 |
2015年 | 306篇 |
2014年 | 402篇 |
2013年 | 1395篇 |
2012年 | 809篇 |
2011年 | 2279篇 |
2010年 | 2150篇 |
2009年 | 1854篇 |
2008年 | 1866篇 |
2007年 | 2130篇 |
2006年 | 371篇 |
2005年 | 648篇 |
2004年 | 667篇 |
2003年 | 791篇 |
2002年 | 489篇 |
2001年 | 299篇 |
2000年 | 299篇 |
1999年 | 260篇 |
1998年 | 251篇 |
1997年 | 210篇 |
1996年 | 223篇 |
1995年 | 197篇 |
1994年 | 190篇 |
1993年 | 214篇 |
1992年 | 201篇 |
1991年 | 202篇 |
1990年 | 166篇 |
1989年 | 171篇 |
1988年 | 150篇 |
1987年 | 145篇 |
1986年 | 158篇 |
1985年 | 260篇 |
1984年 | 254篇 |
1983年 | 225篇 |
1982年 | 205篇 |
1981年 | 204篇 |
1980年 | 220篇 |
1979年 | 205篇 |
1978年 | 166篇 |
1977年 | 183篇 |
1976年 | 150篇 |
1975年 | 144篇 |
1974年 | 128篇 |
1973年 | 132篇 |
1971年 | 100篇 |
1970年 | 103篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Using data on job approval ratings of governors, U.S. senators, and the president, we find that firms located in states with high approval ratings outperform firms located in states with low approval ratings by .64% per month. Furthermore, this relationship is stronger when investors are actively involved in politics, when local politicians are closer to the center of political power, for small firms that have a larger proportion of local investors, and for financially strong areas where investors are ready to execute investments in local stocks. Overall, our study shows that investors’ political sentiment is important in determining stock returns. 相似文献
992.
993.
Yong Tao 《Journal of Evolutionary Economics》2016,26(3):467-500
This paper provides attempts to formalize Hayek’s notion of spontaneous order within the framework of an Arrow-Debreu economy. Our study shows that, if a competitive economy is sufficiently fair and free, a spontaneous economic order will emerge in long-run competitive equilibria so that social members spontaneously occupy an unplanned distribution of income. Despite this, the spontaneous order may degenerate in the form of economic crises whenever an equilibrium economy approaches the extreme competition. Remarkably, such a theoretical framework of spontaneous order provides a bridge linking Austrian economics and neoclassical economics, where a truth begins to emerge: “Freedom promotes technological progress”. 相似文献
994.
995.
996.
L. H. Chuang B. G. Verheggen M. Charokopou D. Gibson S. Grandy B. Kartman 《Journal of medical economics》2016,19(12):1127-1134
Objective: To assess the cost-effectiveness of exenatide 2?mg once-weekly (EQW) compared to dulaglutide 1.5?mg QW, liraglutide 1.2?mg and 1.8?mg once-daily (QD), and lixisenatide 20?μg QD for the treatment of adult patients with type 2 diabetes mellitus (T2DM) not adequately controlled on metformin.Methods: The Cardiff Diabetes Model was applied to evaluate cost-effectiveness, with treatment effects sourced from a network meta-analysis. Quality-adjusted life years (QALYs) were calculated with health-state utilities applied to T2DM-related complications, weight changes, hypoglycemia, and nausea. Costs (GBP £) included drug treatment, T2DM-related complications, severe hypoglycemia, nausea, and treatment discontinuation due to adverse events. A 40-year time horizon was used.Results: In all base-case comparisons, EQW was associated with a QALY gain per patient; 0.046 vs dulaglutide 1.5?mg; 0.102 vs liraglutide 1.2?mg; 0.043 vs liraglutide 1.8?mg; and 0.074 vs lixisenatide 20?μg. Cost per patient was lower for EQW than for liraglutide 1.8?mg (?£2,085); therefore, EQW dominated liraglutide 1.8?mg. The cost difference per patient between EQW and dulaglutide 1.5?mg, EQW and liraglutide 1.2?mg, and EQW and lixisenatide 20?μg was £27, £103, and £738, respectively. Cost per QALY gained with EQW vs dulaglutide 1.5?mg, EQW vs liraglutide 1.2?mg, and EQW vs lixisenatide 20?μg was £596, £1,004, and £10,002, respectively. In the probabilistic sensitivity analysis, the probability that EQW is cost-effective ranged from 76–99%.Conclusion: Results suggest that exenatide 2?mg once-weekly is cost-effective over a lifetime horizon compared to dulaglutide 1.5?mg QW, liraglutide 1.2?mg QD, liraglutide 1.8?mg QD, and lixisenatide 20?μg QD for the treatment of T2DM in adults not adequately controlled on metformin alone. 相似文献
997.
To source external knowledge, firms in the service area use various sourcing modes simultaneously suitable for their internal needs or external environments. Each external knowledge sourcing mode has distinctive characteristics, and as such, they can offer different advantages and/or disadvantages to the firms. Thus, the effects of external knowledge sourcing on service innovation may vary depending on the sourcing modes. The current study aims to empirically examine the different effects of various external knowledge sourcing modes on service innovation. The study identifies three external knowledge sourcing modes: joint development, technology purchasing, and external information acquisition. Three hypotheses are established to examine the relationships between the extent of utilizing each mode and service innovation performance in terms of new service introduction. The data for analysis are selected from the “Korean Innovation Survey 2006: Service Sector” (KIS 2006). It is regarded as South Korea's version of the Community Innovation Survey (CIS). The KIS 2006 data set covers joint development, technology purchasing, and external information acquisition activities of corporations in the service sector in South Korea. The study empirically analyzes the data set using a negative binomial regression model. The results first demonstrate that the extent of the joint development has an inverted U‐shaped relationship with the service innovation performance. Second, the results indicate that, on the other hand, service innovation performance decreases with the increase to the extent of the technology purchasing when the extent is below the threshold. On the other hand, it increases with the increase to the extent of the technology purchasing; this occurs when the extent exceeds the threshold. Third, the results show that external information acquisition has a positive effect on service innovation performance. These findings support that the extent of utilizing each mode has different relationships with service innovation performance. The findings suggest that service firms need to utilize joint development at a moderate level, active technology purchasing, and as much external information acquisition as possible to maximize service innovation performance. In practice, this finding can help managers of service firms select appropriate external knowledge sourcing modes and determine the optimum level of use for each mode. This study also can help firms build up strategies for external knowledge sourcing. 相似文献
998.
999.
We analyze optimal merger policy in R&D-intensive industries with product innovation aiming to improve the quality of products. Our results suggest that a permissive merger policy is rarely optimal in high-tech industries when the antitrust authority considers a welfare standard that balances the impact of mergers on consumers’ surplus and firms’ profits. In particular, relative to a benchmark where the effects from R&D are absent, we show that the optimal merger policy should not be substantially more permissive in the presence of those effects from R&D. 相似文献
1000.
This paper considers the assignment of tradable permits—representing property rights of an environmental good—to community members who are harmed by pollution generated by firms. These community members can in turn sell permits to polluters according to their personal preferences. For a special case with a sole household, market transactions between the household and polluters achieve an efficient pollution level. However, for a group of households, the decentralized market solution fails to yield social efficiency because of competitive consumption of the environmental goods. We design a revenue-sharing mechanism akin to unitization, under which market transactions also achieve efficient resource allocation. Importantly, in some cases, efficiency can be achieved even when regulators are ignorant of the private valuation of the environmental good. 相似文献