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   4636篇
  免费   99篇
  国内免费   11篇
财政金融   151篇
工业经济   118篇
计划管理   491篇
经济学   844篇
综合类   273篇
运输经济   77篇
旅游经济   168篇
贸易经济   293篇
农业经济   2041篇
经济概况   290篇
  2024年   25篇
  2023年   95篇
  2022年   81篇
  2021年   120篇
  2020年   262篇
  2019年   108篇
  2018年   127篇
  2017年   242篇
  2016年   208篇
  2015年   142篇
  2014年   267篇
  2013年   300篇
  2012年   260篇
  2011年   391篇
  2010年   302篇
  2009年   291篇
  2008年   238篇
  2007年   302篇
  2006年   253篇
  2005年   181篇
  2004年   123篇
  2003年   97篇
  2002年   78篇
  2001年   90篇
  2000年   40篇
  1999年   28篇
  1998年   13篇
  1997年   15篇
  1996年   4篇
  1995年   24篇
  1994年   8篇
  1993年   5篇
  1992年   4篇
  1991年   2篇
  1990年   1篇
  1988年   1篇
  1986年   1篇
  1985年   8篇
  1984年   7篇
  1982年   1篇
  1981年   1篇
排序方式: 共有4746条查询结果,搜索用时 15 毫秒
61.
土地利用规划是一项多学科、多部门、多时序的系统工程,其规划决策过程中涉及到许多半结构及非结构化问题,需要地理信息系统和决策支持系统的共同作用。本文从九个方面对我国当前土地利用规划决策支持新趋势进行了探讨。  相似文献   
62.
研究目的:明确国土空间用途管制的转型逻辑,探究国土空间用途管制制度完善路径。研究方法:文献梳理法与综合分析法。研究结果:(1)国土空间用途管制属于在地化的空间管制创新模式,是在新的价值理念与治理需求引导下的空间治理转型实践。(2)国土空间用途管制的治理目标是实现国土空间系统性、激励性与高效能管制,其治理逻辑是将国土空间用途管制小闭环嵌入到国土空间治理大闭环之中,实现自然资源部内部治理“小协同”与以自然资源部为核心的多部门治理“大协同”联动。(3)可从构建全域全要素全过程的国土空间用途管制体系、优化系统治理的“三条控制线”划定及管制规则、规范与创新国土空间用途管理政策体系、建立健全多部门权力协同机制以及利益调节机制等方面探索国土空间用途管制完善路径。研究结论:国土空间用途管制涉及多学科交叉、需要理论联系实践,将来研究要加强理论综合支撑顶层设计、关注区域差异鼓励地方创新以及尊重主体利益提高管制效能。  相似文献   
63.
研究目的:科学探究乡村数字化转型对耕地绿色利用效率的影响机制,为推进乡村数字化转型赋能耕地绿色生产提供理论依据。研究方法:非期望产出SBM模型,Tobit回归模型和面板门槛回归模型。研究结果:(1)中国耕地绿色利用率均值由2011年0.628上升至2021年0.845,年均增幅2.17%,空间上呈现“东部、西部、中部”和“粮食主销区、产销平衡区、粮食主产区”依次递减格局;(2)乡村数字化转型水平均值由2011年0.127增长至2021年0.259,年均增幅10.49%,空间上呈现“东部、中部、西部”和“粮食主销区、粮食主产区、产销平衡区”依次递减非均衡格局;(3)中国乡村数字化转型对耕地绿色利用效率具有显著促进作用且存在区域异质性,东、中部地区乡村数字化转型的促进作用较西部地区更为显著,粮食主产区和产销平衡区较粮食主销区更为显著;(4)乡村数字化转型水平越过门槛值0.261时,对耕地绿色利用效率促进作用呈现边际效应递减的单门槛非线性特征。研究结论:区域间应联通数字赋能耕地绿色利用的合作共享网络、扩大数字技术对耕地利用环境污染的缓释效应和衔接耕地利用主体数字化耕种需求,是实现耕地绿色利用的长效驱动路径。  相似文献   
64.
在中央提出科学发展观与构建和谐社会的新形势下,我国各类中心城市在土地开发中应当坚持可持续发展原则,进行有序、合理地开发,实现城市人口、资源、环境各要素的协调发展。本文回顾了城市土地可持续利用的相关理论,指出了城市可持续发展与土地可持续利用的关系,重点研究了当前我国中心城市土地可持续利用的战略选择。  相似文献   
65.
The spread of free trade agreements (FTAs) in Southeast Asia has ignited a debate about their impact on enterprises including the business costs from the Asian ‘noodle bowl’ effect. This paper undertakes a comparative and firm-level analysis of the determinants of FTA use in Indonesia, Malaysia and the Philippines. The likelihood of firms using important ASEAN+1 FTAs (e.g. the ASEAN-China FTA, the ASEAN-Japan FTA and ASEAN-Korea FTA) is positively associated with acquiring knowledge about FTAs, building technological capabilities, and membership in industrial clusters. Non-use of FTAs is explained by a lack of information about FTAs and the absence of FTAs with major trading partners. Key policy implications are the need to improve business support for FTAs, to conclude FTAs with major trading partners, and to create a database on FTA preference use.  相似文献   
66.
Objective:

To define the in-hospital and 6-month post-discharge resource use, following Transcatheter Aortic Valve Implantation (TAVI) and conventional Aortic Valve Replacement (AVR) surgery within a single UK hospital.

Methods:

A local service evaluation of patients undergoing TAVI or AVR between January 2011 and May 2012 captured data until 6-months post-procedure, collected from hospital records and via a General Practitioner questionnaire. The main end-points were mortality, time in ITU/HDU, hospital length of stay (LoS), discharge destination, re-admission, and post-discharge primary/secondary care resource use. Sub-group analyses were performed for AVR patients aged ≥80 (AVR?≥?80) and with EuroSCORE of ≥10 (AVR ES?≥?10) to allow more direct comparison with ‘TAVI type’ patients.

Results:

Results are given as means (standard deviation) for TAVI (n?=?51), AVR (n?=?188), AVR?≥?80 (n?=?48), and AVR ES?≥?10 (n?=?47), respectively, unless otherwise stated. Age in years was 83.0 (8.1), 71.2 (13.1), 84.1 (2.7), 79.4 (7.1); EuroSCORE was 24.7 (11.9), 8.1 (6.4), 12.0 (6.0), and 16.5 (6.6); post-operative LoS (days) was 11.5 (11.2), 10.9 (10.8), 14.3 (16.7), and 15.2 (17.7). For discharged patients, 0%, 7%, 13%, and 9% had unplanned cardiac-related re-admissions within 30-days of discharge. Time to first readmission was 74.6 (34.0), 35.0 (34.2), 20.8 (9.7), and 22.6 (14.3) days.

Limitations:

This was a single-center retrospective evaluation, not prospectively powered to confirm differences in outcomes.

Conclusions:

Despite TAVI being performed in an older, higher risk population, LoS was similar to AVR. Most strikingly there were no cardiac-related re-admissions within 30-days for TAVI and time to first re-admission was significantly longer. This evaluation suggests that TAVI is clinically appropriate and provides economic advantages in both the hospital and post-discharge setting in this high risk group. Many patients undergoing TAVI are considered unfit for surgery and, hence, TAVI offers a treatment that delivers similar results to traditional AVR without the high risk associated with surgery.  相似文献   
67.
徐梦辉 《时代经贸》2014,(6):179-179
在经济全球化大环境下,企业具有更加多样化的会计信息,也就更需要能全面反映企业业绩的财务分析体系。多年来传统杜邦分析法虽因能系统、全面、直观地反映企业财务状况,提高对财务报表的分析效率,提升经营管理能力而得到企业的广泛应用,但它本身存在着诸多缺陷。针对其局限性,本文引入可持续增长率来改进传统的杜邦分析体系以更加符合现代企业的要求。  相似文献   
68.
In the search for solutions to complex real-world problems, the benefits of transdisciplinary research (TDR) have been widely heralded. Land use science appears to be a designated field for TDR. However, to date, the additional expenses of TDR are accompanied by a so far not proved added value, and empirical findings are claimed to be scarce and dispersed over several disciplines and case studies.We reviewed 299 articles obtained from a structured literature search to (1) investigate the current differences between theory and practice, (2) identify empirical findings, and (3) ascertain the contributions of TDR to promoting sustainable land use management.Our results demonstrate that, in spite of an increasing conceptual consistency in the theoretical discussion of TDR, the implementation of TDR remains a substantial challenge, in part because of the gap between theory and practice. In addition, research on TDR is science and process centred. The benefits of TDR in addressing real-world problems within the field of land use remain unproven.  相似文献   
69.
Land use regulation has always been regarded as one of the most crucial means of macro-control of urban growth, which can affect a city’s land values directly and further determine related urban economic well-being. Since the New Type Urbanization Strategy proposed by the government in 2014, China’s mode of urban growth has been transformed from addressing “quantity” to “quality" in the urbanization process. In this case, the regulation of land use by the Chinese government plays a more important role in urban growth. With their planned land regulatory scheme, the various instruments employed by Chinese governments have quite different mechanisms influencing land prices. However, there are no rigorous studies focusing on the land use regulation system and its impact on land values to date, particular in China. This study seeks to explore how land use regulation affects urban land values through the systematic lens. We summarize the main land use regulatory instruments based on the analysis of China’s planned land use system and urban land banking system, including the construction land quota, constraints on the allowed floor area ratio (FAR) of each land transaction parcel, and land supply restrictions. A new dataset based on land transaction data from 2007 to 2016 that covers 286 prefectural cities from the country’s coastal, central, and western regions is used in the empirical analysis. The results show that the effects of the floor area ratio (FAR) on land values are significant and positive, with the residential and commercial land supply ratio being a key factor. Moreover, the results imply that the effects of constraints on FAR and commercial land supply vary between regions. These findings indicate that the Chinese land market is considerably distorted by excessive administrative interventions by local governments, in the stage of urban transition guided, the capable regulatory instruments could play an important role in adjusting urban land prices and hence impact on urban growth.  相似文献   
70.
Aims: This study compared the risk for major bleeding (MB) and healthcare economic outcomes of patients with non-valvular atrial fibrillation (NVAF) after initiating treatment with apixaban vs rivaroxaban, dabigatran, or warfarin.

Methods: NVAF patients who initiated apixaban, rivaroxaban, dabigatran, or warfarin were identified from the IMS Pharmetrics Plus database (January 1, 2013–September 30, 2015). Propensity score matching (PSM) was used to balance differences in patient characteristics between study cohorts: patients treated with apixaban vs rivaroxaban, apixaban vs dabigatran, and apixaban vs warfarin. Risk of hospitalization and healthcare costs (all-cause and MB-related) were compared between matched cohorts during the follow-up.

Results: During the follow-up, risks for all-cause (hazard ratio [HR]?=?1.44, 95% confidence interval [CI]?=?1.2–1.7) and MB-related (HR?=?1.57, 95% CI?=?1.0–2.4) hospitalizations were significantly greater for patients treated with rivaroxaban vs apixaban. Adjusted total all-cause healthcare costs were significantly lower for patients treated with apixaban vs rivaroxaban ($3,950 vs $4,333 per patient per month [PPPM], p?=?.002) and MB-related medical costs were not statistically significantly different ($100 vs $233 PPPM, p?=?.096). Risk for all-cause hospitalization (HR?=?1.98, 95% CI?=?1.6–2.4) was significantly greater for patients treated with dabigatran vs apixaban, although total all-cause healthcare costs were not statistically different. Risks for all-cause (HR?=?2.22, 95% CI?=?1.9–2.5) and MB-related (HR?=?2.05, 95% CI?=?1.4–3.0) hospitalizations were significantly greater for patients treated with warfarin vs apixaban. Total all-cause healthcare costs ($3,919 vs $4,177 PPPM, p?=?.025) and MB-related medical costs ($96 vs $212 PPPM, p?=?.026) were significantly lower for patients treated with apixaban vs warfarin.

Limitations: This retrospective database analysis does not establish causation.

Conclusions: In the real-world setting, compared with rivaroxaban and warfarin, apixaban is associated with reduced risk of hospitalization and lower healthcare costs. Compared with dabigatran, apixaban is associated with lower risk of hospitalizations.  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