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   185篇
  免费   4篇
财政金融   5篇
工业经济   20篇
计划管理   18篇
经济学   54篇
综合类   4篇
贸易经济   20篇
农业经济   53篇
经济概况   15篇
  2021年   3篇
  2020年   4篇
  2019年   3篇
  2018年   3篇
  2017年   3篇
  2016年   3篇
  2015年   2篇
  2014年   10篇
  2013年   46篇
  2012年   6篇
  2011年   10篇
  2010年   13篇
  2009年   7篇
  2008年   12篇
  2007年   8篇
  2006年   12篇
  2005年   10篇
  2004年   7篇
  2003年   7篇
  2002年   13篇
  2001年   2篇
  2000年   1篇
  1999年   1篇
  1994年   1篇
  1993年   1篇
  1991年   1篇
排序方式: 共有189条查询结果,搜索用时 46 毫秒
151.
This paper explores the national and transnational character of mobilization against GM crops in India, South Africa and Brazil in the ten-year period to 2005. By examining the contexts and practices of mobilization across the three countries, and in particular the complex, often fraught, local and global connections, the paper examines the diverse mobilizations that have occurred. The paper argues that to understand these processes, particular national political and economic contexts must be appreciated, alongside how the GM debates articulate with other foci for activism and the complex and often fragile nature of alliances that make up activist networks. The paper shows how the debate about GM crops has become a much wider one: about the future of agriculture and small-scale farmers, about corporate control and property rights and about the rules of global trade. In sum, a debate not just about the pros and cons of a particular set of technologies, but about politics and values and the future of agrarian society.  相似文献   
152.
全球化背景下,创新对经济发展具有重要的推动作用。近10年来,学术界掀起了对创新活动研究的高潮,经济学家、经济地理学家、管理学家从不同的视角对创新的形成动机、过程、模式及演变进行了相关研究。研究显示,一方面,创新是集体行动的结果,企业间互动对创新的发生具有积极作用;另一方面,创新网络要素结构差异对创新功能的实现也有着不同的影响。因此,将基于集体学习机制,从网络个体与整体结构差异出发,分析和总结结构差异下不同创新网络模式特点,并以浦东生物医药产业创新网络作为实证案例。  相似文献   
153.
This article employs a propensity score‐matching approach to examine the direct effects of adoption of Bacillus thuringiensis (Bt) cotton on yields, pesticide demand, household income and poverty, using cross‐sectional data from a survey of farmers in the Punjab province of Pakistan. Generally, the findings reveal that adoption of the new technology exerts a positive and significant impact on cotton yields, household income and poverty reduction, and a negative effect on the use of pesticides. The positive and significant impact of the technology on yields and household income is consistent with the potential role of new agricultural technology in directly reducing rural poverty through increased farm household income.  相似文献   
154.
为适应21世纪生物经济发展趋势,培养21世纪新型生物技术人才,结合我校实际,通过提高实验课时所占总课时的比例,增加实验课的内容,整合药学相关实验资源,结合综合性实验、设计性实验、创新性实验,改革"理论-实践"的教学环节,多指标综合评分考核等对药学实验教学进行改革,获得新型药学实验教学模式。  相似文献   
155.
We examine the strategic incentive for gene holders to vertically integrate with seed companies and chemical input companies. With homogeneous conventional seeds, we find that a pure bundling strategy (produce the genetically modified seed only) is dominant. When the gene holder and breeder are, respectively, the monopolistic producers of genetically modified and conventional seeds, they may commit to mixed bundling (supply both genetically modified and conventional seed) to deter potential entry to the conventional seed market. A vertical merger may solve the credibility issue of the mixed bundling commitment through third party licensing agreements in the conventional seed market.  相似文献   
156.
We examine the economic effects of the introduction of consumer-oriented genetically modified (GM) products into the food system by developing a model of heterogeneous consumers and producers that allows for vertical and horizontal differentiation between the products available to consumers. The model facilitates the estimation of consumer and producer surpluses in the product/utility and product/net returns spaces. Results show that the introduction of consumer-oriented GM products can change the relationship between GM and conventional and organic products from one of vertical to one of horizontal product differentiation and can enhance both economic welfare and the market acceptance and growth of agricultural biotechnology.  相似文献   
157.
德国的工业生物技术具有很长的历史,目前在各行业的应用迅速增长.通过发展工业生物技术,德国提高了工业的竞争力和创造了大量就业机会.德国具有发展工业生物技术的雄厚工业基础及技术优势,但缺乏风险资本和配套政策.因此,目前德国正在研究发展工业生物技术的相关政策.  相似文献   
158.
Increased investment in agricultural research could contribute to sustainable development goals and benefit farmers, consumers, the environment, and the economy. This paper provides recent evidence and a critical assessment of the evolving Canadian canola crop development and innovation policy and compares it to the wheat and pulse sectors that differ in degree of biotechnology adoption, seeded acreage, intellectual property rights, and private sector involvement. This study also assesses how crop characteristics and technological changes affect future optimal public policy. A number of innovation policies are discussed that could stimulate further growth within the crop sector.  相似文献   
159.
160.
Classical innovation adoption models implicitly assume homogenous information flow across farmers, which is often not realistic. As a result, selection bias in adoption parameters may occur. We focus on tissue culture (TC) banana technology that was introduced in Kenya more than 10 years ago. Up till now, adoption rates have remained relatively low. We employ the average treatment effects approach to account for selection bias and extend it by explicitly differentiating between awareness exposure (having heard of a technology) and knowledge exposure (understanding the attributes of a technology). Using a sample of Kenyan banana farmers, we find that estimated adoption parameters differ little when comparing the classical adoption model with one that corrects for heterogeneous awareness exposure. However, parameters differ considerably when accounting for heterogeneous knowledge exposure. This is plausible: while many farmers have heard about TC technology, its successful use requires notable changes in cultivation practices, and proper understanding is not yet very widespread. These results are also important for other technologies that are knowledge‐intensive and require considerable adjustments in traditional practices.  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