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   13309篇
  免费   902篇
  国内免费   237篇
财政金融   619篇
工业经济   494篇
计划管理   2503篇
经济学   2884篇
综合类   1678篇
运输经济   79篇
旅游经济   193篇
贸易经济   1743篇
农业经济   2335篇
经济概况   1920篇
  2024年   63篇
  2023年   426篇
  2022年   378篇
  2021年   557篇
  2020年   565篇
  2019年   409篇
  2018年   374篇
  2017年   446篇
  2016年   499篇
  2015年   439篇
  2014年   890篇
  2013年   1090篇
  2012年   1092篇
  2011年   1244篇
  2010年   953篇
  2009年   832篇
  2008年   962篇
  2007年   789篇
  2006年   663篇
  2005年   486篇
  2004年   350篇
  2003年   259篇
  2002年   171篇
  2001年   168篇
  2000年   93篇
  1999年   54篇
  1998年   37篇
  1997年   35篇
  1996年   33篇
  1995年   25篇
  1994年   13篇
  1993年   16篇
  1992年   12篇
  1991年   7篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1987年   1篇
  1986年   3篇
  1985年   3篇
  1984年   1篇
  1983年   4篇
  1981年   1篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
61.
Ownership is considered to be one of the crucial governance mechanisms; however, there have been no systematic attempts at validating the construct and measures used to operationalize ownership. We review the current understanding of ownership and the measures used by each perspective, namely blockholder/dispersed shareholder perspective, owner identity perspective, and aggregated ownership perspective. We thereafter critique each of these perspectives, offer hypotheses regarding their validity, and empirically assess each ownership measure vis‐à‐vis firm performance outcomes. We utilize a sample of 3,990 US firms to test our hypotheses and find no consistent results for the blockholder measure, or for the owner identity measure. However, the aggregated ownership measure consistently accounts for significant increases in explanation of variance in firm performance. Copyright © 2018 ASAC. Published by John Wiley & Sons, Ltd.  相似文献   
62.
湖南省农业生态与农业经济耦合性测度   总被引:3,自引:0,他引:3  
[目的]考察湖南省近9年来农业生态与农业经济系统耦合发展现状,探究二者发展过程中的规律,以期找出二者协调发展模式,并为湖南省农业生态环境保护、农业经济发展提供决策依据。[方法]运用耦合协调度模型,基于熵权法为各指标进行客观确定权重,结合2007~2015年湖南省农业生态与农业经济发展的相关数据,确定农业生态与农业经济的耦合匹配分析模型,采用熵值赋权法确定各项指标的权重,构建农业生态—农业经济耦合协调评价指标体系。[结果]研究结果表明,2007~2015年湖南省农业生态与农业经济的耦合协调发展基本稳定,耦合度值均在0.9以上,二者呈协调发展趋势。其中,2014年和2015年二者的耦合度较高,分别为0.975 3和0.984 3,说明湖南省在这两年的农业生态与农业经济的协调性好,农业经济与农业生态能够相互有效促进彼此的发展。同时,仍需时刻关注生态环境的承载力,降低对自然资源的无序攫取,实现经济的可持续发展。  相似文献   
63.
Low agricultural productivity remains the primary source of poverty in the developing regions and yet little is known about the influence on agricultural productivity of domestic and international accumulated R&D knowledge and the channels through which this knowledge is transmitted internationally. Following a large scientific literature, this article argues that R&D and R&D knowledge spillover are ecozone‐specific and, therefore, are transmitted internationally through ecozones, where ecozones are the broadest biogeographic division of the earth's land surface. Using data for a panel of 88 countries, it is shown that international knowledge spillovers are ecozone‐specific and have been an important contributing factor behind the marked widening of the income gap between developed and developing countries since 1983.  相似文献   
64.
本试验以感官评定、菌落总数、pH值和DPPH自由基清除能力为指标,探究不同浓度的壳聚糖溶液处理对以紫花地丁和大麦为主要原料的复合饮料的保质期影响。结果表明,壳聚糖添加量在1.5%时饮料的感官评分较高,菌落总数的增长受到有效抑制,pH值下降受到抑制,具有良好的抗氧化稳定性。研究结果可为紫花地丁复合饮料的研发试验提供理论基础。  相似文献   
65.
The main aim of this paper was to understand a guest’s decision to stay at a green hotel by using the theory of planned behavior (TPB) developed by Ajzen (1991). The population for this study was green hotel customers in Taiwan. A total of 425 usable responses were received from the willing participants around the parking area of green hotels. This study performed a PLS-SEM to examine the proposed model. The results of this study showed that social pressure has very little direct impact on behavioral intention to stay at a green hotel. The results of the estimated standardized regression coefficients and t-values indicated that perceived behavioral control has a slightly higher impact on behavioral intention than attitude. This study also verified the proposed mediating relationships between the first-order and second-order antecedents. This study provided theoretical and managerial implications for understanding respondents’ decision to stay at a green hotel.  相似文献   
66.
[目的]通过对山西省乡村休闲旅游地的空间分布特征及影响因素进行研究,旨在为山西省的乡村旅游发展提供合理的参考建议。[方法]选取山西省213处国家级和省级乡村旅游示范点为研究对象,运用最临近点指数对其空间分布类型进行判别,并运用地理集中指数和地理联系率对其分布均衡程度和地理联系程度进行考量,通过核密度图进一步分析其空间分布指向,在此基础上对影响因素进行分析。[结果]山西省乡村休闲旅游地空间分布呈集聚分布的特点,且与经济规模和人口密度在空间上的均衡、配合程度较高。[结论](1)山西省乡村休闲旅游地包括以太原和晋中为主的中部密集区和以临汾、运城、晋城为主的南部密集区,且都以各地级市为中心向周边扩展,大多数示范点分布于城郊地区; (2)经济发展、人口密度、资源禀赋、区位因素和社会因素是影响山西省乡村休闲旅游地分布的主要因素,其中农业科技类、农事体验类和特色村镇类多分布于经济和人口密度较高的地区。  相似文献   
67.
[目的]通过分析什邡市耕地质量现状,充分把握影响耕地质量的主导因素并进行质量提升分区,测算不同质量提升区的提升潜力,以期为全市耕地质量的建设与发展指明方向。[方法]依据农用地分等理论,构建2014年什邡市耕地质量限制性指数评价体系,采用限制性指数模型测算耕地质量限制性指数,结合因素组合法、耕地质量潜力测算法,分别进行耕地质量提升分区及其提升潜力评价。[结果]什邡市耕地质量现状差异显著,地域分布特征明显;因素限制程度以中限制为主,多因素共同主导限制耕地比重大;各质量分区限制特征明显,各区耕地质量提升潜力在时序上和空间上也存在差异。高等别耕地集中分布于南部平原,受土壤酸碱度中等限制和剖面构型高程度限制为主;北部丘陵区以及南部河谷低洼地带主要为低等别耕地,表现为坡度与灌溉因素较高程度限制为主;综合提升潜力较大的耕地集中于北部丘陵区与南部河谷低洼地带。[结论]什邡市范围内耕地质量差异明显,存在普遍限制且分区限制特征明显,各区提升潜力空间差异明显。  相似文献   
68.
Swedish census data and tax records reveal an astonishing decline in the aggregate skill premium of 30 percent between 1970 and 1990, with only a modest recovery in the next couple of decades. In contrast, the US skill premium rose by around 24 percent over those four decades. A theory that equalizes wages with marginal products can rationalize these disparate outcomes when we replace commonly used measures of total labor supplies by private sector employment. The dramatic decline in the skill premium in Sweden is the result of an expanding public sector that has disproportionately hired unskilled labor.  相似文献   
69.
[目的]实现我国粮食安全与农业结构调整之间(即粮食增产和农民增收)关系的协调,较长时间以来是学界、政界关注的重要议题,但定量分析两者之间内在依存关系的研究一直欠缺。[方法]文章采用协整分析及Granger因果关系检验方法,以广东为例,对我国粮食安全(用粮食总产量来衡量)与农业结构调整水平之间的协整性及因果关系进行了研究。[结果]广东粮食总产量与反映农业结构调整水平的3个指标之间均存在长期均衡关系,且农作物播种面积中粮食作物面积对广东粮食总产量影响最大,每下降1%,粮食总产量下降0. 659 548%。短期内,反映农业结构调整水平的3个指标对广东粮食总产量的影响均存在波动,但由短期偏离拉向长期均衡的牵动作用均较弱。Granger因果关系检验表明农业在国民经济中的比重、农作物播种面积中粮食作物面积早期对广东粮食总产量产生单向影响,但影响程度相对较弱。[结论]提出应从农业结构调整以外的因素着手提高我国粮食安全水平,并通过调整农业区域结构去缓解我国粮食供求市场的结构性矛盾。  相似文献   
70.
Background: Inhibitor development to factor VIII (FVIII) hemophilia therapy results in increased complications and substantial economic costs. The SIPPET study, the first randomized controlled trial to compare the immunogenicity of plasma-derived FVIII (pdFVIII)/von Willebrand factor (VWF) and recombinant-DNA-derived FVIII (rFVIII), demonstrated higher inhibitor rates in previously untreated patients (PUPs) treated with rFVIII than in PUPs treated with pdFVIII/VWF.

Objective: To quantify the economic impact of treating PUPs with pdFVIII/VWF vs rFVIII.

Methods: An Excel-based clinical and economic model was developed from a US healthcare payer perspective and run over a 5-year period. The analysis utilized a cohort approach to model patient treatment and outcomes over a monthly cycle to quantify differences in costs of FVIII, bypassing agents, and hospitalizations for serious bleeds. Rates of high-titer inhibitor development were obtained from the SIPPET study. Patients developing high-titer inhibitors were treated with immune tolerance induction (ITI). Patients who developed low-titer inhibitors and those who did not develop inhibitors continued their usual FVIII treatment. Patients who were successfully treated with ITI returned to FVIII treatment, while unsuccessfully treated patients received bypassing agents. Total costs per treated patient were estimated and a one-way sensitivity analysis was conducted to quantify the impact of parameter uncertainty on the model outcomes.

Results: Total cumulative costs per patient over 5 years were $834,621 for pdFVIII/VWF patients and $1,237,163 for rFVIII patients, representing a total saving of $402,542 per patient over the 5-year period, for an average annual saving of $80,508 per patient.

Conclusions: Based on data from the SIPPET study, this analysis found that initiating FVIII treatment in severe hemophilia A PUPs with pdFVIII/VWF has the potential to offer substantial cost savings to healthcare payers, amounting to a one-third reduction in costs.  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