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251.
This paper summarizes and comments on the methodology actually employed in participatory planning of R&D activities for the iron and steel industry in Turkey. Through an organized collaboration with more than a hundred managers, engineers, experts, and planners: (1) technical, managerial, financial, and social problems that are obstacles to the achievement of predetermined goals for the industry are identified and defined; (2) these problems are formulated as R&D candidate projects; and (3) a set of R&D candidate projects are selected for implementation in the 1980s.  相似文献   
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Microeconomic theory is the theory of individual choice. For macroeconomic problems to be analyzed and solutions proposed with microeconomic theory, such problems must be capable of being defined in individualistic terms. It is argued that individuals can never perceive truly social problems requiring collective action in a manner consistent with the requirements of microeconomic theory. Even reformulating microeconomic theory to allow for interpersonal comparisons of utility, individuals may not be able to perceive the nature of social concerns in a manner necessary to support individually motivated actions bringing forth a solution.  相似文献   
254.
This paper examines the international mixed duopoly behaviour with research spillovers. Using a two‐stage game with Research and Development (R&D) and output, we investigate the effects of imperfectly appropriable R&D on optimal R&D strategies of a domestic public firm and a foreign private firm across different market interactions: (i) international R&D competition, (ii) only the foreign firm conducts R&D, (iii) only the domestic public firm conducts R&D, (iv) no firm conducts R&D, and (v) research joint venture. The results show that firms' research performances are determined by the degree of spillovers and the optimal R&D strategies involve R&D competition. Spillovers are shown to be socially beneficial and their absence can prove to be a strategic deterrent, with the public firm monopolising the market. Some of these findings contrast with the traditional models of oligopoly (with or without R&D) and mixed oligopoly (without R&D).  相似文献   
255.
The author considers the potential for a link between the recent pattern of demographic transition and intertemporal and inter-country variations in savings rates. Fertility, infant mortality, life expectancy, and levels of female and child labor force participation are among the various demographic factors which affect national savings rates through their effects upon age structure, age-specific individual savings behavior, and their general equilibrium effects upon interest rates, wage rates, and income distribution. The author establishes a simple discrete time life cycle model of savings, explains the issues related to age structure, and discusses the effect of age-specific savings functions, the general equilibrium effects of demographic factors, the effects of life expectancies and child mortalities, and the nature of social security coverages in less developed countries, as well as issues which are especially important for less developed countries. A new strategy for empirically evaluating demographic policies is proposed. That is, one can estimate the age profile of earnings, saving and fertility rates from household survey data. The life tables can then be used to compute the aggregate savings rate and population size. Any demographic policy which affects the fertility rate, life expectancy, and investment in the quality of children will change the aggregate saving and population growth rates. These two aggregate effects could be compared to evaluate demographic policies. The author stresses, however, that changes in different demographic factors will have different short-run and long-run effects upon the savings rate which will also depend upon whether such changes are transitory or permanent.  相似文献   
256.
Valuing ecosystem services: A shadow price for net primary production   总被引:4,自引:0,他引:4  
We analyze the contribution of ecosystem services to GDP and use this contribution to calculate an empirical price for ecosystem services. Net primary production is used as a proxy for ecosystem services and, along with capital and labor, is used to estimate a Cobb Douglas production function from an international panel. A positive output elasticity for net primary production probably measures both marketed and nonmarketed contributions of ecosystems services. The production function is used to calculate the marginal product of net primary production, which is the shadow price for ecosystem services. The shadow price generally is greatest for developed nations, which have larger technical scalars and use less net primary production per unit output. The rate of technical substitution indicates that the quantity of capital needed to replace a unit of net primary production tends to increase with economic development, and this rate of replacement may ultimately constrain economic growth.  相似文献   
257.
Objectives: To examine treatment patterns, treatment effectiveness, and treatment costs for 1 year after patients with rheumatoid arthritis switched from a tumor necrosis factor inhibitor (TNFi) (adalimumab, certolizumab pegol, etanercept, golimumab, or infliximab), either cycling to another TNFi (“TNFi cyclers”) or switching to a new mechanism of action (abatacept, tocilizumab, or tofacitinib) (“new MOA switchers”).

Methods: This retrospective cohort study used administrative claims data for a national insurer. Treatment persistence (without switching again, restarting, or discontinuing), treatment effectiveness (defined below), and costs were assessed for the 12-month post-switch period. Patients were “effectively treated” if they satisfied all six criteria for a treatment effectiveness algorithm (high adherence, no dose increase, no new conventional synthetic disease-modifying anti-rheumatic drug, no subsequent switch in therapy, no new/increased oral glucocorticoids, and <2 glucocorticoid injections). Multivariable logistic models were used to adjust for baseline factors.

Results: The database included 581 new MOA switchers and 935 TNFi cyclers. New MOA switchers were 39% more likely than TNFi cyclers to persist after the switch (odds ratio [OR]?=?1.39; 95% confidence interval [CI]?=?1.12–1.74; p?=?.003) and 36% less likely to switch therapy again (OR?=?0.64; 95% CI?=?0.51–0.81; p?p?=?.006). New MOA switchers had 16% lower drug costs than TNFi cyclers (cost ratio?=?0.84; 95% CI?=?0.79–0.88; p?p?Limitations: Claims payments may not reflect rebates or other cost offsets. Medical and pharmacy claims do not include clinical end-points or reasons that lead to new MOA switching vs TNFi cycling.

Conclusions: These results support switching to a new MOA after a patient fails treatment with a TNFi, which is consistent with recent guidelines for the pharmacologic management of established rheumatoid arthritis.  相似文献   
258.
This paper explores whether expert judgements can be taken as a proxy for citizen preferences for determining investment strategies for public goods. As an illustration, we focus on the provision of Public Rights Of Way (PROW) by Local Government Authorities in England. These provide rights of passage over property to those other than the owners, and little information is available on the welfare effects of changes in the provision and use of PROW. Given limited funds, reliance on expert judgement could be a cost effective alternative for decision-making compared with stated preference surveys of citizens. Two methods are compared. The Analytic Hierarchy Process (AHP) is used to elicit expert judgement to proxy citizen preferences for different attributes of PROW. The Choice Experiment (CE) technique is then used to derive preferences directly through personal interviews with citizens. Overall it was found that judicious use of AHP by experts can, in this instance, be used to represent citizen views. However, this result may not be easily generalisable to other settings.  相似文献   
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