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31.
Operating cash flow (CFO) asymmetric timeliness occurs when CFO reflects bad news more quickly than good news. We examine the presence and determinants of CFO asymmetric timeliness in Australia, where substantial differences in reporting requirements of cash flow components, in characteristics of listed companies and in the degree of conservative financial reporting produce contrasting findings to those in the United States. We find supportive evidence for the novel ‘sticky cost behaviour’ explanation and also the product-pricing strategy, but not the life cycle hypothesis. These findings are useful for investors and analysts concerned with forecasting the future values of companies.  相似文献   
32.
Abstract

Objective: This study aimed to compare the cost-effectiveness of ramucirumab versus placebo for patients with hepatocellular carcinoma who progressed on sorafenib with α-fetoprotein concentrations (AFP) of at least 400?ng/ml in the United States.

Methods: A Markov model was constructed to assess the cost-effectiveness of ramucirumab. Health outcomes were measured as quality-adjusted life years (QALYs). With TreeAge software, the disease process was modeled as three health states: progression-free survival (PFS), progressive disease (PD), and death. Costs were extracted from the REACH-2 trial, and utility was derived from published literature. Incremental cost-effectiveness ratios (ICERs) were calculated to compare ramucirumab with placebo. Probabilistic sensitivity analyses were developed to examine the robustness of the results.

Results: In the base case analysis, ramucirumab therapy had a cost of $55,508.41 and generated 0.54 QALYs, while placebo therapy had a cost of $761.09 and generated 0.47 QALYs, leading to an additional $54,747.32 in costs and 0.07 QALYs. The ICER was $782,104.57 per QALY, which was much higher than the willingness-to-pay threshold of $100,000 per QALY. According to sensitivity analyses, the utility of PD in the two groups was the dominant parameter influencing the ICER.

Conclusion: Although ramucirumab was associated with prolonged survival for patients with advanced hepatocellular carcinoma who progressed on sorafenib treatment with an AFP of at least 400?ng/ml, it is not a cost-effective treatment from a United States payer perspective.  相似文献   
33.
This article provides an in‐depth, longitudinal analysis combining real‐time and retrospective data on a set of Mondragon's industrial cooperatives that are organized as international groups. We examine the life cycle of these international cooperative groups, which is expected to evolve differently to that of small‐ and medium‐sized cooperatives that operate exclusively on a local scale. The article is theoretically informed by the cooperative life cycle theory, as well as by recent insights from the degeneration and regeneration theses. Our analysis yields an intricate picture of the evolution of cooperatives faced with a ‘grow‐or‐die’ dichotomy. On the one hand, our findings reject the highly simplistic and deterministic view of the degeneration thesis by demonstrating that these cooperatives can mobilize resources to revitalize cooperative values and practices. On the other, we find that regeneration may not occur in a consistent, sequential fashion as the previous literature suggests, but rather degenerative and regenerative tendencies can occur simultaneously, even leading to long‐lasting, unresolvable situations. In light of this, the article asks future research to draw on power‐aware and politically informed approaches for further understanding of how cooperatives manage the tensions at each organizational stage of their life cycle, and of which organizational actors benefit, and how, from reversing some degenerative tendencies while maintaining others intact.  相似文献   
34.
新的结构发展期,加快资源型产业升级对经济可持续和高质量发展至关重要。将可耗竭资源因素引入有关产业结构和技术创新的理论模型中,分析技术创新对资源型产业转型升级的作用机理。将地区产业划分为资源型产业和创新型产业,借助夹角余弦的思想构建资源型产业升级的动态指标,利用2005-2016年间中西部地区17个省、市、自治区(西藏除外)面板数据进行计量分析。结果显示:技术创新是资源型产业升级的内生驱动力,而政府的调节效应却因资源型产业发展阶段的不同而不同。为此,需根据资源型产业的发展阶段,制定适宜的转型升级策略。对处于成熟期的资源型产业,宜借助政府的政策引导和调节作用,激励企业向非资源型产业发展。对处于衰竭期的资源型产业,则要更加注重创新技术的培育和应用转化。  相似文献   
35.
Social media platforms have become an (almost) obligatory part of our lives and activities. However, many disadvantages have emerged such as an increase in dependency on social media owing to addictions known as the dark side of social media. The current research seeks to understand the impact of specific aspects of this dark side, viz. social media addiction, fear of missing out, and narcissism, on self-esteem, and their links with an individual's satisfaction with life (SwL). The results of a quantitative survey (n = 260) show the salient impact of these aspects on self-esteem as well as the preponderant role of collective self-esteem in SwL. Academic and managerial implications are discussed.  相似文献   
36.
37.
为进一步提升中短码长下准循环低密度奇偶校验(Quasi-cyclic Low-density Parity-check,QC-LDPC) 码的纠错性能,提出了一种综合短环数目和环连通性的QC-LDPC码构造方法。首先,采用Golomb规则构造QC-LDPC码,对基矩阵中的部分元素进行替换预处理,初步降低短环数目;其次,采用所提的利用近似环外信息度(Approximate Cycle Extrinsic message degree,ACE)的消环掩模算法来优化QC-LDPC码,使得掩模后的校验矩阵具有较大的ACE平均值,最终完成QC-LDPC码的构造。该构造方法简单、通用性强,在短环数目和连通性间进行了平衡。与只考虑减少短环数目、增大围长等方法相比,该方法构造的QC-LDPC码有更加优异的纠错性能。  相似文献   
38.
The management of supply chains is becoming more important in economic and social environments. Currently, the social sustainability is a factor that must be considered to design governmental strategies and policies. The objective of this research paper was to show, with a case study an approach to optimize distribution and delivery logistics of food in a social assistance program of school breakfast using mathematical models that include transportation distance, optimal locations, and vehicle routing through different clusters. By using qualitative variables like poverty levels, food insecurity and social exclusion, different clustering methods are proposed with the purpose of identifying the common characteristics in the studied population; and at the same time, reducing the distribution complexity. The results show an efficient approach to design a supply chain that includes economic and social factors. The new model developed in this paper can be used to plan social assistance governmental programs, to identify the specific needs and characteristics of the beneficiaries, minimizing the total cost of the distribution network logistics when delivering food for school meals.  相似文献   
39.
Within a continuous time life cycle model of consumption and savings, I study the properties of the most general class of additive intertemporal utility functionals. They are not necessarily stationary, and do not necessarily multiplicatively separate a discount factor from “per-period utility”. I prove rigorously that time consistency holds if and only if the per-period felicity function is multiplicatively separable in t, the date of decision and in s, the date of consumption, or equivalently, if the Fisherian instantaneous subjective discount rate does not depend on t. The model allows to explain “anomalies in intertemporal choice” even when the agents are time consistent and various empirical regularities. On the other hand, the model allows to characterize mathematically the “effective consumption profile” of naive, time-inconsistent agents.  相似文献   
40.
This study examines the effect of the state of the economy and inventory on interest-adjusted bases and expected returns for five energy commodities. We find that interest-adjusted bases and returns have a business cycle pattern. Consistent with the theory of storage, demand shocks near business cycle peaks generate negative interest-adjusted bases and positive returns. In recessions, the bases become positive, and the average returns are negative. Our regression results also show that the interest-adjusted bases of energy commodities are counter-cyclical and the expected returns are pro-cyclical. For petroleum commodities, inventory has a significant effect on interest-adjusted bases at low levels of inventory, whereas at high inventory levels the effect of inventory on the bases is weak. Finally, we find that the bases and economic conditions predict spot returns in energy commodity markets.  相似文献   
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