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991.
Iron deficiency is very widespread, with adverse consequences for health and cognition. Iron supplementation is not popular for long-term use, and cereal fortification is not feasible where milling occurs locally. Double-fortified salt (DFS: using both iron and iodine) is an alternative. The study undertakes a literature survey to find the effect of DFS on hemoglobin, and then uses a previous algorithm to make calculations for India. The benefit:cost ratio was estimated as 2.4:1 if only the benefits to children and women were included, and between 4:1 and 5:1 if anemia levels for men also decreased. This is just a little lower than the median ratio estimated for iron fortification of cereal staples (6.7:1), for home fortification for children less than two (37:1), and for biofortification – breeding for high iron – of cereals (high, but no exact figure available). Double-fortified salt is therefore a good alternative for improving iron status in populations where fortification of other staple foods does not achieve desired coverage. 相似文献
992.
Recent studies of purchasing power parity (PPP) use panel tests that fail to take into account heterogeneity in the speed of mean reversion across real exchange rates. In contrast to several other severe restrictions of panel models and tests of PPP, the assumption of homogeneous mean reversion is still widely used and its consequences are virtually unexplored. This paper analyzes the properties of homogeneous and heterogeneous panel unit root testing methodologies. Using Monte Carlo simulation, we uncover important adverse properties of the panel approach that relies on homogeneous estimation and testing. More specifically, power functions are low and assume irregular shapes. Furthermore, homogeneous estimates of the mean reversion parameters exhibit potentially large biases. These properties can lead to misleading inferences on the validity of PPP. Our findings highlight the importance of allowing for heterogeneous estimation when testing for a unit root in panels of real exchange rates. 相似文献
993.
Daniel G. Arce M 《Managerial and Decision Economics》2005,26(6):397-405
This paper integrates economics and business ethics through the use of the subgame perfection/backward induction decision rule. It is shown that textbook examples of subgame perfection differ in their ethical complexity. Specifically, predatory pricing is difficult to justify on both game‐theoretic and ethical grounds, whereas ‘poison pill’ takeover defenses have complex economic and ethical ramifications. Further, I employ backward induction to examine two additional areas of ethics and management decision‐making: product recall (the Ford Explorer and Firestone tires), and price versus advertising competition. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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M.S. Reed A. Bonn W. Slee N. Beharry-Borg J. Birch I. Brown T.P. Burt D. Chapman P.J. Chapman G.D. Clay S.J. Cornell E.D.G. Fraser J.H. Glass J. Holden J.A. Hodgson K. Hubacek B. Irvine N. Jin M.J. Kirkby W.E. Kunin F. Worrall 《Land use policy》2009
Upland areas provide UK society with many important functions, goods and services, but have experienced a number of disturbing trends and face an uncertain future. This paper outlines historic, current and future drivers of environmental, economic, socio-cultural and policy change in UK uplands, and assesses how these have affected or are likely to affect ways in which land is used and the provision of ecosystem services. Information is synthesised into scenarios summarising a range of possible futures anticipated for UK uplands to 2060 and beyond. Finally, innovations in science, technology, governance and policy are evaluated that could enable uplands to continue providing key ecosystem services under a range of scenarios. The paper concludes that many upland areas will need to be prepared for significant reductions in grazing and prescribed burning. Conversely, other areas could experience agricultural intensification, for example significant increases in grazing or an expansion of arable or bioenergy crops into upland valleys, due to anticipated increases in global demand for food and energy. These scenarios will take place in the context of climate change. Many may take place together and may interact with each other, with complex and unpredictable implications for the upland environment, economy and society. In this context, a number of advances are needed in science, technology and policy to maintain viable upland communities and the future provision of ecosystem services. These may include funding for ecological and hydrological restoration via carbon offsetting or other means. It may also involve advances in ecosystem service modelling, mapping and valuation, which through stakeholder participation could facilitate more integrated rural planning. New forms of environmental governance need to be explored that can empower those interested in developing upland economies to maintain thriving upland communities, while managing the ecosystem services they provide as efficiently as possible. 相似文献
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Julian M. Alston Michele C. Marra Philip G. Pardey & T. J. Wyatt 《The Australian journal of agricultural and resource economics》2000,44(2):185-215
A total of 289 studies of returns to agricultural R&D were compiled and these provide 1821 estimates of rates of return. After removing statistical outliers and incomplete observations, across the remaining 1128 observations the estimated annual rates of return averaged 65 per cent overall — 80 per cent for research only, 80 per cent for extension only, and 47 per cent for research and extension combined. These averages reveal little meaningful information from a large body of literature, which provides rate-of-return estimates that are often not directly comparable. This study was aimed at trying to account for the differences. Several features of the methods used by research evaluators matter, in particular assumptions about lag lengths and the nature of the research-induced supply shift. 相似文献