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31.
Mortality,Human Capital and Persistent Inequality   总被引:4,自引:0,他引:4  
Available evidence suggests high intergenerational correlation of economic status and persistent disparities in health status between the rich and the poor. This paper proposes a mechanism linking the two. We introduce health capital into a two-period overlapping generations model. Private health investment improves the probability of surviving from the first period of life to the next and, along with education, enhances an individual’s labor productivity. Poorer parents are of poor health, unable to invest much in reducing mortality risk and improving their human capital. Consequently, they leave less for their progeny. Despite convex preferences and technologies, initial differences in economic and health status may perpetuate across generations when annuities markets are imperfect.Additional support was provided by the National Science Foundation. Additional support was provided by the National Science Foundation.  相似文献   
32.
Altruism and the Economic Values of Environmental and Social Policies   总被引:2,自引:0,他引:2  
Altruism is a type of non-use value which can have different definitions depending on the type of goods entering the utility function of the altruists and their expectations about the contributions of others. The purpose of this paper is to measure the trade-offs between different types of altruist values originating from social and environmental policies. Environmental policies are concerned with reducing health effects from a power plant while social policies involve both the attainment of public facilities for education and leisure and an increase in the income of the affected population. The empirical application utilizes a choice experiment technique which allows for valuation of multiple goods. Health effects are decomposed into the values of the risk of becoming ill, the duration of the episodes and the limitations imposed by illness. Altruist values are elicited from a population that is not affected by pollution. Results show that altruism is significant for policies directed to reducing health effects and improving the income level of the affected population, whereas there is egoism for a policy aimed at improving public facilities in the polluted suburb. The value of altruism is significantly influenced by the expectations of net benefits to be received by the affected population.  相似文献   
33.
Mixed logit models represent a powerful discrete choice analytical model but require assumptions about the functional form of the parameter distributions. The use of unbounded distributions, such as the normal distribution, may be regarded as unsuitable where theory indicates that all are negatively affected by increases in an attribute, such as price. Bounded distributions such as the triangular and log-normal are unable to model the case where a section of the population is indifferent towards an attribute, while the remainder are negatively disposed toward it. Train and Sonnier’s bounded mixed logit model accommodates these features and is employed in this paper. A censored normal and Johnson’s Sb distribution are used to model preferences in the UK for food attributes, including price and GM technology. Bi-modal distributions are identified regarding GM food: some are unlikely to ever consume it, some are close to indifference and willing to consume at relatively small discounts while the remainder are fairly unresponsive to further price reductions.  相似文献   
34.
我国绿色食品出口贸易中存在的问题及对策探析   总被引:5,自引:1,他引:5  
20世纪90年代以来,绿色食品贸易在全球兴起并已成为人类社会可持续发展的必然选择。然而,尽管在国内绿色食品生产日益社会化、市场化、国际化的背景下,我国绿色食品已经呈现出蓬勃发展的良好态势,但出口数量和出口规模还是偏低。本文在分析我国绿色食品出口中存在的问题及原因的基础上,探索相应的对策,以期为我国绿色食品竞争优势的提升提供有益的思路。  相似文献   
35.
食品供应链综合管理的核心内容是质量认证与跟踪管理,其思想为解决我国食品供应链中的安全问题提供了基本的思路。本文在分析我国食品供应链中存在的与食品安全相关的问题基础上,对我国实践食品安全供应链综合管理进行了思考,提出了从宏观、中观、微观三个层面上进行食品安全供应链综合管理的框架,并对食品安全供应链综合管理中的信息集成与共享进行了探讨。  相似文献   
36.
中国粮食生产区域分化特征和成因的实证研究   总被引:3,自引:0,他引:3  
薛宇峰 《经济经纬》2005,(2):105-109
对中国在1990年和2002年粮食生产的区域分化状况进行统计分析的结果表明,工业化和城市化的发展,以及农产品市场形成条件下,稻米生产的区域分散特征、小麦生产的区域集中特征以及玉米播种面积的集中和生产产量的分散特征日益明显。计量检验显示,人均承包经营耕地面积和种植业收入比率是影响粮食生产区域分化的最主要的两个因素。  相似文献   
37.
我国农业生态系统营养循环链的断裂与重建   总被引:9,自引:0,他引:9  
完整的营养循环是农业生态系统健康、可持续发展的重要保障。我国传统农业属于环境友好型生态农业。农业生态系统的营养循环结构完整,持续健康、繁荣。但是,随着工业化、城市化、市场经济的发展以及农业耕作方式的转变,农业生态系统营养循环的结构遭到严重破坏,导致一系列资源、环境、经济与社会问题。通过秸秆还田以及城市生活废弃物(排泄物、厨房垃圾等)向农业生态系统的返还,重建农业生态系统完整的营养循环,是我国农业生态系统持续健康发展的必由之路。  相似文献   
38.
This paper estimates the dose-response relationship between air pollution and the number of work loss days for the Netherlands. The study is based on illness data (work loss days) for the Dutch labour population and average year concentrations of air pollution in 29 districts. The dose-response relationship has been estimated by means of two different techniques: the ordinary least squares method (OLS) and the one-way fixed-effects method (OWFEM), which we consider to be more adequate. In general health effects are much smaller when OWFEM is applied than if OLS is used. With OWFEM a significant relationship is found between sulphate aerosol (SO4), ammonia (NH3) and the number of work loss days (WLDs). Particulates (TSP), O3 and SO2 have no significant effect on the number of WLDs. These results differ from those obtained in studies in the United States, which indicate that particulates (TSP) and other small particles, ozone (O3) and to a lesser extent SO4 and SO2 significantly influence the number of WLDs.  相似文献   
39.
目的汇总分析北京市16个区县近100家社区卫生服务中心处方抽样点评的结果,比较各区之间的差异,细化点评结果,促进全市合理用药。方法抽取2017年6月第2周,全门诊不包括草药处方,共计50189张处方,进行精细化集中点评。结果2017年北京16个区县社区卫生服务中心平均处方金额为160.07元,注射剂使用率为5.56%,全部基本药物占比为68.29%,处方的不合理率为8.8%。结论对于北京市社区卫生服务中心门诊处方集中点评最应改进的为统一点评标准,其次还应完善处方管理,强化药剂师自身的业务学习.  相似文献   
40.
Background: Validation of overall survival (OS) extrapolations of immune-checkpoint inhibitors (ICIs) during the National Institute for Health and Care Excellence (NICE) Single Technology Assessment (STA) process is limited due to data still maturing at the time of submission. Inaccurate extrapolation may lead to inappropriate decision-making. The availability of more mature trial data facilitates a retrospective analysis of the plausibility and validity of initial extrapolations. This study compares these extrapolations to subsequently available longer-term data.

Methods: A systematic search of completed NICE appraisals of ICIs from March 2000 to December 2017 was performed. A targeted search was also undertaken to procure published OS data from the pivotal clinical trials for each identified STA made available post-submission to NICE. Initial Kaplan-Meier curves and associated extrapolations from NICE documentation were extracted to compare the accuracy of OS projections versus the most mature data.

Results: The review identified 11 STAs, of which 10 provided OS data upon submission to NICE. The extrapolations undertaken considered parametric or piecewise survival models. Additional data cut-offs provided a mean of 18 months of OS beyond the end of the original data. Initial extrapolations typically under-estimated OS from the most mature data cut-off by 0.4–2.7%, depending on the choice of assessment method and use of the manufacturer- or ERG-preferred extrapolation.

Conclusion: Long-term extrapolation of OS is required for NICE STAs based on initial immature OS data. The results of this study demonstrate that the initial OS extrapolations employed by manufacturers and ERGs generally predicted OS reasonably well when compared to more mature data (when available), although on average they appeared to underestimate OS. This review and validation shows that, while the choice of OS extrapolation is uncertain, the methods adopted are generally aligned with later-published follow-up data and appear appropriate for informing HTA decisions.  相似文献   

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