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61.
新时代中国城市土地集约利用若干问题的再认识   总被引:2,自引:0,他引:2  
研究目的:基于中国城市土地集约利用研究现状,面向新时代要求,重新审视与厘清城市土地集约利用理论认知、评价标准、影响机制和优化调控等基本问题,为中国土地集约利用的理论完善和实践创新提供支撑。研究方法:理论分析法和推理演绎法。研究结果:(1)城市土地集约利用在理论认知上应由“三个阶段”转向“三个时期”;(2)城市土地利用集约度的评价标准应由静态指标转向动态耦合;(3)城市土地集约利用的影响机制研究应由封闭区域转向关联传导;(4)城市土地集约利用优化调控策略应由极限集约转向最优集约。研究结论:进入新时代,城市土地集约利用理论上可实现“不增地,多增效”甚至“地减量,效增加”,未来相关研究应重点关注存量和减量规划中建设用地与经济发展之间关系的变化特征,以及国土空间规划与土地利用计划管理改革下新的城市土地集约利用问题。国家相关规程中的集约评价标准须结合区域发展阶段进行“匹配性”修正,政策制定要考虑区域间的“关联性”和“传导性”进行精准化设计,治理方案应按照最优集约度的“动态性”进行差异化调控。  相似文献   
62.
Background: Biologic treatments have enhanced the treatment outcomes of patients with active ankylosing spondylitis (AS). Until recently, TNF-alpha-inhibitors have been the only biologics approved for the treatment of active AS. The objective of this study was to assess the potential financial impact of the first non-TNF-alpha biologic secukinumab (fully human IL-17A-inhibitor) vs adalimumab (TNF-alpha-inhibitor) in the treatment of AS in Finland.

Materials and methods: In this model-based budget impact analysis, patients were treated either with secukinumab (150?mg) or adalimumab (40?mg). The number of patients and market share of different biologics were based on national reimbursement registry data. Adalimumab was the most commonly used biologic treatment for AS, and in the base case analysis all adalimumab patients are assumed to switch to secukinumab. Response rates were based on a matching-adjusted indirect comparison between secukinumab and adalimumab. Patients not achieving response were switched to another biologic treatment.

Results: Treating AS patients with secukinumab instead of adalimumab leads to potential savings of 18.2 million euros within a 5-year time period. The total costs within the follow-up time were 59.5 million euros and 77.7 million euros with and without secukinumab, respectively. According to sensitivity analyses, a higher adoption rate of secukinumab corresponds to higher potential savings.

Conclusions: Secukinumab is a cost-saving treatment option compared with adalimumab in the treatment of AS in Finland. More patients could be treated with a biologic by allocating resources more efficiently.  相似文献   
63.
With the rapid urbanization in China, land resources are becoming increasingly scarce. Identifying and resolving land use conflict is essential for reasonably using land resources and achieving land sustainability. Taking the middle reaches of the Heihe River as an example, we included the constraints of local water resources to construct a multi-criteria evaluation system for assessing land use competitiveness in 2000 and 2015 based on land use, socio-economic, and nighttime light data. By comparing the competitiveness of cultivated land, construction land and ecological land, we then derived the spatiotemporal patterns of potential land use conflicts. Actual land use changes supported the hypothesis that land use tended to convert into the type with higher competitiveness at areas with intense conflict, which better indicated that our assessment model was effective. The results showed that the potential land use conflict was more acute in the central and northwest but weak in the southeast and northeast, and its pattern showed a significantly positive spatial autocorrelation. The conflict between cultivated land and construction land was most prominent and mainly occurred in the transitional zone from urban to rural areas. Rapid urban development and water shortage were the main causes of the potential land use conflict. Assessing land use multi-functions and making a tradeoff among ecological, economic, and social services will be an effective way to guide future land use to solve land use conflict. Our research provides scientific evidence for sustainable land use planning and management in the arid areas.  相似文献   
64.
Given the marked heterogeneous conditions in smallholder agriculture in Sub-Saharan Africa, there is a growing policy interest in site-specific extension advice and the use of digital extension tools to provide site-specific information. Empirical ex-ante studies on the design of digital extension tools and their use are rare. Using data from a choice experiment in Nigeria, we elicit and analyze the preferences of extension agents for major design features of ICT-enabled decision support tools (DSTs) aimed at site-specific nutrient management extension advice. We estimate different models, including mixed logit, latent class and attribute non-attendance models. We find that extension agents are generally willing to use such DSTs and prefer a DST with a more user-friendly interface that requires less time to generate results. We also find that preferences are heterogeneous: some extension agents care more about the effectiveness-related features of DSTs, such as information accuracy and level of detail, while others prioritise practical features, such as tool platform, language and interface ease-of-use. Recognising and accommodating such preference differences may facilitate the adoption of DSTs by extension agents and thus enhance the scope for such tools to impact the agricultural production decisions of farmers.  相似文献   
65.
[目的]在系统梳理浙江省绿色农业发展进程基础上,文章从农业资源综合利用的视角,基于经济社会发展、资源减量投入、资源循环利用和资源环境安全4个维度构建绿色农业综合评价指标体系,并评价浙江省绿色农业发展水平。[方法]借鉴BPEIR概念模型构建浙江绿色农业生产系统概念模型和评价指标体系,采用灰色关联分析法并结合宏观统计数据,从动态视角评价了2002—2016年浙江省绿色农业发展状况,并静态比较2015年浙江省11个地级市农业绿色发展的基本状况。[结果]浙江省绿色农业资源综合利用指数呈波动上升趋势,在不同的发展阶段,农业资源综合利用指数也呈现出规律性变化; 浙北地区绿色农业资源综合利用指数明显高于浙南地区; 杭州、嘉兴、宁波位居前三,金华市绿色农业资源综合利用指数最低。[结论]浙江绿色农业发展水平呈不断上升趋势,不同地区差异明显; 实行差异发展、完善政策体系、提高质量品牌、强化科技支撑是推进浙江农业绿色发展的关键。  相似文献   
66.
Economic reform in China has resulted in rapid urbanisation over the past three decades, changing the urban and rural landscape dramatically. A large amount of farmland was developed, leading to conflict between construction demand and farmland protection. In response, the “Link Policy” was proposed in 2005 that seeks to concurrently preserve farmland while providing for urban expansion through land exchange. The effectiveness of the Link Policy has not been systematically investigated. The purpose of this study is to analyse and evaluate outcomes of the Link Policy objectives from both a participant and investigator’s interpretive perspective. Ezhou, the first experimental city to implement the Link Policy in Hubei Province in central China, was selected as a case study area. Eight different communities in Ezhou were visited and 160 semi-structured interviews were conducted with resettled rural residents in March 2016. A combination of interviews and investigator field observations were used to evaluate the Link Policy objectives. The results show that participants recognize and support improving rural living conditions and coordinating urban-rural development, but the Link Policy failed to achieve the objectives of preserving farmland, protecting farmers’ land use rights and interests, and facilitating agricultural production. Participants perceived concentrated resettlement communities to be more efficient in land use compared to more expansive rural settlements, but vacant apartments for commercial use in resettlement areas account for a large proportion of land suggesting inefficiency in the land exchanges. We suggest policy changes to achieve more successful implementation of the Link Policy.  相似文献   
67.
研究目的:作为保障首都生态环境质量与可持续发展的关键区域,北京市西北生态涵养区的生态健康程度反映了生态文明战略部署下首都高质量发展的综合成效。本文通过构建北京市西北生态涵养区健康评价指标体系,评价该区域的生态健康程度,为生态涵养区的可持续发展提供对策建议。研究方法:PSR模型、层次分析法(AHP)。研究结果:(1)基于PSR模型构建的生态健康评价指标体系包括压力、状态和响应系统3个准则层和10个评价指标,涵盖涵养区自然生态和人类活动影响;(2)研究区4个时段的健康指数分别为0.673、0.664、0.650、0.687,生态健康等级为一般。研究结论:北京市西北涵养区生态健康状况较为稳定,在保持西北涵养区建设现有成果的基础上,需要加大生态建设的力度,进一步提高生态健康水平。  相似文献   
68.
本文根据免费开放科技馆的功能属性,确定了科技馆免费开放评估指标体系的构建原则,考虑不同角度评估工作的重点,设计了适应不同主体和要求的科技馆免费开放评估指标体系,包括免费开放科技馆自评估指标体系、各级科协主管部门自评估指标体系和科技馆免费开放第三方评估指标体系,最后对主要指标和考察要点进行了总结说明。本文的研究成果,可以为免费开放科技馆和科协主管部门开展自评估以及第三方评估提供标准和依据,规范免费开放科技馆的评估和运行管理,为中国特色现代科技馆体系建设提供支持,为科技馆事业的可持续发展提供参考。  相似文献   
69.
沈阳城市周边耕地多功能评价   总被引:4,自引:0,他引:4  
[目的]为探索城市化影响下城市周边耕地多功能的现状,分析其空间差异,为耕地保护及城市周边耕地发展提供参考。[方法]从耕地的生产、生态、社会和景观4个功能出发构建评价指标体系,利用熵权法确定指标权重,加权求和法计算单一功能和多功能值,并用ArcGIS进行空间分析,对沈阳城市周边50个乡镇(街道)的耕地多功能性进行综合评价。[结果](1)沈阳城市周边耕地的多功能性空间差异较为明显。生产功能远郊平原区最强,远郊山区和近郊区较弱;生态功能总体偏弱,个别乡镇较好;距离城市越远,社会功能越强;景观功能近郊区较强,远郊区较弱。(2)耕地的生态、社会和景观功能主要受距市中心距离的影响,生产功能受地形和距市中心距离的双重影响,而多功能则受地形、距市中心距离及各乡镇(街道)耕地主导功能等的综合影响。(3)沈阳城市周边的大多数耕地以农业生产为主导,景观文化功能整体相对较弱。近郊区耕地生态功能所占比重较大,但社会功能比重较小,远郊区则与之相反。[结论]沈阳城市周边耕地多功能性空间差异较为明显且不均衡,应科学规划城市周边耕地功能,优化空间布局,协调耕地各功能的关系,促进耕地多功能综合发展。  相似文献   
70.
[目的]随着经济的快速发展,我国各地区都面临着不同程度的农业生态脆弱性,通过研究特殊地形和气候下的农业生态脆弱性,有助于为农业生态环境的综合治理提供参考。[方法]文章以广西为例,通过构建评价指标体系,采用层次分析法和熵权法确定综合权重,通过构建综合评价模型对广西农业生态脆弱性程度进行评价,利用ArcGIS对生态脆弱性进行分级,以期探究广西农业生态脆弱性的空间分布情况。[结果]权重分析结果表明水蚀面积的权重值最高为0134,年平均降水量的权重值为0113,自然环境指标相对于农业生产和经济指标对农业生态脆弱性的影响更大。区划研究结果表明广西农业生态脆弱性区域大致可分为5个区域,分别是桂西峰丛洼地带、桂东山地丘陵地带、桂中低山丘陵地带、桂东北山地、桂南沿海丘陵地带。[结论]广西农业生态环境整体来看较为脆弱,处于轻度和中度脆弱等级,但生态环境问题仍不容忽视。为了改善农业生态脆弱性,政府应实行区域的联合防治,加大对农业生态环境的监督和治理,积极探寻生态、环保的农业发展方式,调整产业结构,改善农业生态环境的状态,促进广西农业的可持续发展。  相似文献   
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