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   34111篇
  免费   686篇
财政金融   5959篇
工业经济   2411篇
计划管理   5668篇
经济学   7726篇
综合类   570篇
运输经济   186篇
旅游经济   489篇
贸易经济   5650篇
农业经济   1427篇
经济概况   4613篇
信息产业经济   3篇
邮电经济   95篇
  2021年   171篇
  2020年   283篇
  2019年   384篇
  2018年   1148篇
  2017年   1142篇
  2016年   865篇
  2015年   392篇
  2014年   621篇
  2013年   2893篇
  2012年   920篇
  2011年   1419篇
  2010年   1168篇
  2009年   1242篇
  2008年   1271篇
  2007年   1293篇
  2006年   717篇
  2005年   753篇
  2004年   794篇
  2003年   818篇
  2002年   663篇
  2001年   621篇
  2000年   623篇
  1999年   528篇
  1998年   535篇
  1997年   513篇
  1996年   514篇
  1995年   457篇
  1994年   501篇
  1993年   519篇
  1992年   476篇
  1991年   513篇
  1990年   461篇
  1989年   384篇
  1988年   392篇
  1987年   384篇
  1986年   401篇
  1985年   574篇
  1984年   537篇
  1983年   543篇
  1982年   523篇
  1981年   448篇
  1980年   441篇
  1979年   449篇
  1978年   386篇
  1977年   347篇
  1976年   278篇
  1975年   268篇
  1974年   250篇
  1973年   239篇
  1972年   199篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
991.
In today's tough economic environment, governments at all levels face significant budget shortfalls and public rail transit systems must compete with other public services for government subsidies. It is critical that public rail transit systems be concerned with their operational performance and efficient use of resources. In this paper, we develop a methodology that measures a rail transit system's performance relative to that of other rail transit systems, compares its performance to an appropriate efficient benchmark system, and identifies the sources of its inefficiency. We analyze the relationship between public subsidies and operational performance of public rail systems and show an inverse relationship between subsidization and efficiency.  相似文献   
992.
This article argues for a reconceptualization of one of the most basic concepts in urban studies: the neighborhood. Traditionally neighborhoods have been understood as clearly bounded, quasi‐Westphalian containers or as ‘natural areas’ of urban community. But this approach is widely acknowledged to be under‐theorized. And it fails to account for the ways in which the production of neighborhood is inherently political and often conflictual. After reviewing the ways in which neighborhood has been used in urban sociology and urban planning, this article offers a critical conception of neighborhoods as ‘spatial projects’ on the submetropolitan scale. This approach captures the ways in which neighborhoods are not abstract spaces on a city map, but the uneven, unequal products of complex, ongoing struggles between various groups and institutions. This approach is developed through an ethnographic and historical case study of neighborhood formation in one part of Brooklyn, New York. The article concludes with a discussion of how the language of spatial projects refocuses urban research on the political and economic forces that produce neighborhood in the contemporary city.  相似文献   
993.
Understanding the social processes that support innovations in new biotechnologies presents an interesting challenge. Evidence from the Australian bioindustry reveals how the development and integration of new biotechnologies is a dynamic social process. Our findings highlight how new technology acceptance and integration rested on the micro‐politics of sense‐making and relational networking.  相似文献   
994.
In this article, we broaden the focus of existing research on employee stock purchase plans by analysing employee preferences for investing in employer stock as a construct distinct from actual investment behaviour. In our analysis of original survey data in a sample of 900 employees in four French companies, we find that employee preferences are influenced by two common cognitive heuristics (representativeness and familiarity), organisational commitment, the perceived quality of corporate communications about these plans and perceived managerial commitment to employee ownership. We did not find, however, that risk aversion, turnover intentions or perceived employee involvement in decision making influenced preferences for investing in employer stock. Our findings have both theoretical and practical implications for understanding and operating these types of employee benefit plans, which are becoming more common across the globe.  相似文献   
995.
Major sports events draw unsurpassed media attention. Companies are motivated to increase their advertising investments around these events to reach large audiences in a short period. Is such an advertising surge actually beneficial though, or should companies avoid advertising in these periods because of negative effects of competitive interference? This study investigates when consumer packaged goods companies should invest in advertising to increase sales: before, during, or after the event or outside these event periods. The author estimates short- and long-term own- and cross-advertising elasticities for 206 brands using four years of weekly data. Although considerable heterogeneity exists across brands, own-advertising effectiveness diminishes especially before and during major sports events, in both the short and the long run. In addition, brands benefit less from category-demand effects through competitors' advertising. Conversely, greater increases in advertising spending resulting in significant growth in share of voice around focused, single-sport events are a successful strategy to overcome this overall general negative trend.  相似文献   
996.
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   
997.
The article analyzes the impact of the collapse of world oil prices on the reduction of defense budget, production of weapons, innovative and personnel potential of the defense industry, and on country’s defense capability. Some proposals for the concept of structural changes in the defense industry have been formulated based on experience converting the defense industries in the Soviet Union, the United States, China, and France.  相似文献   
998.
This paper studies the effects of tariffs on intra-firm trade. Building on the Antràs and Helpman (2004) North–South theoretical framework, I show that higher Northern tariffs reduce the incentives for outsourcing and offshoring, while higher Southern tariffs have the opposite effects. I also show that increased offshoring and outsourcing imply a decrease in the ratio of Northern intra-firm imports to total imports, an empirically testable prediction. Using a highly disaggregated dataset of U.S. (the North) imports and relevant U.S. and foreign tariffs, I find robust evidence to support the model's predictions.  相似文献   
999.
Firms increasingly look to collaboration with alliance partners in their quest for breakthrough innovation. But how does the position of a firm in its alliance network weighted by the centrality of its partners—a concept which we term “partner‐weighted alliance centrality”—and the heterogeneities in the types of partners that it cooperates with—in terms of its private‐public collaboration—influence this quest? Using longitudinal data from the U.S. pharmaceutical industry, we build alliance networks in the period 1985–2001 to investigate these questions. We show that, for breakthrough innovation, collaborating with more partners that are more central in alliance networks the better, but only to a point. Beyond that point, we find that the likelihood of achieving breakthrough innovation drops. Furthermore, and looking at the kinds of knowledge provided by the partners in each firm's alliances, we report that firms with a greater share of private partners, relative to public partners, suffer less from the diminishing benefits of collaboration with central partners when developing breakthrough innovation. Taken together, we make novel contributions about how to organize for breakthrough innovation, and provide actionable managerial advice in terms of selecting collaborative partners in alliance networks.  相似文献   
1000.
In a hold‐up experiment designed to test theoretical predictions following from Hart and deMeza and Lockwood regarding investment behavior, Sonnemans, Oosterbeek and Sloof (SOS) find only a partial confirmation of theory. According to SOS these deviations from standard theory can be explained by positive reciprocal behavior. In this paper, we replicate the experiment by SOS and add another group of treatments in which asset ownership is endogenized by auctioning off the assets. Our experiment shows that the results by SOS crucially depend on the ownership structure being exogenously assigned by the experimenter. We present experimental evidence that, by and large, corroborates the theoretical predictions made by Hart.  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