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51.
Medic (Medicago spp.) pastures are widely grown in rotation with dryland cereal crops in Mediterranean climate zones of Australia. Attempts since the 1960's to introduce this system to Mediterranean west Asia and north Africa (the native region of medic) have not lead to significant adoption; farmers in the region recognize medic, but as a weed and natural pasture plant. This first detailed economic evaluation of the rotational medic system was conducted using a whole-farm linear programming model based on the agricultural system of north-west Syria. The model represents in detail impacts of rotation on yields, labor requirements of alternative farm activities, availability of family and hired labor, subsistence income requirements, livestock feed sources and uses at different times and a choice of sheep stocking rates. Biological data for the analysis are based on a large six-year cropping and grazing experiment near Aleppo on terra-rossa soil with rainfall mainly in winter and averaging about 330 mm annually. The trial compared a dryland medic-wheat system and traditional two-year rotations of wheat with: fallow, watermelon, lentil and vetch. Results indicate that, given current prices and yields from the trial, medic is less profitable than traditional rotations. The model was used to investigate situations in which medic would be economically preferred. Selection of a medic rotation by the model was found to be particularly sensitive to the area of the farm and the price of labor. On small farms, labor availability per hectare is high, favouring the production of labor intensive crops such as lentil and watermelon. On larger farms, labor costs of these enterprises are substantial, increasing the relative profitability of medic, especially if labor prices increase. Interestingly, the relative desirability of medic is more sensitive to its impact on subsequent wheat crops than to the level of pasture production. We also found that modest increases in the prices of sheep products (especially milk) have a major impact on the economic performance of medic. These insights will allow improved focusing and targeting of future research and extension activities.  相似文献   
52.
Extensification of agriculture is one of the major factors contributing to the destruction of forests in Africa. In Sudan, such horizontal expansion comes at the expense of land devoted to trees and other vegetation, thereby inducing conditions that are inimical to sustainable agricultural production. Different factors have contributed to extensification. Although high economic returns from crop (mainly sorghum) production was an important factor encouraging extensification of rainfed mechanized farming, other factors outside agriculture have also contributed to that expansion. This paper uses data from eastern Sudan and an acreage response model, to identify the most important factors influencing acreage expansion. Different measures and forms of risk were used in the acreage response model. The paper shows how policies in the energy sector can indirectly influence acreage expansion in the agricultural sector.  相似文献   
53.
Although many challenges remain, business ethics is flourishing in North America. Prominent organizations give annual business ethics awards, investments in socially screened mutual funds are increasing, ethics officers and corporate ombudspersons are more common and more influential, and new ideas are being tested in practice. On the academic side, two major journals specializing in business ethics are well-established and other major journals often include articles on business ethics and new organizations emphasizing ethics have been initiated. Within business schools, the number of endowed chairs is growing and the ethics curriculum is expanding. Canada is a major player in the business ethics discipline while business ethics in Mexico is just beginning to emerge as a focus of interest in both the business and academic communities.  相似文献   
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This paper summarizes the consequences of safety and health inattentiveness, and reviews four primary dangers in the workplace. In addition, perspectives of employee health and safety are presented from industry and academia which provide the basis for a strong recommendation to include safety and health issues in business school curricula. Wayne H. Stewart's areas of research and teaching interest include Social Responsibility in Management, Entrepreneurship, and International Business. Wayne is currently on the editorial board of the International Journal of Case Studies, and has published in the Journal of Management Learning, as well as participating in several academic conferences. Donna E. Ledgerwood is currently the Secretary for the Southern Management Association. Donna was President of the Southwest Academy of Management in 1993 and served as the Academy of Management's Director of Exhibits/Publisher Relations and Director of Advertising from 1983–1991. Having written one of the first articles on sexual harassment in 1980, Donna serves on the Editorial Review Board for the Journal of Business Strategies and has published in the Labor Law Journal, the Monthly Labor Review, and the Personnel Administrator. Ruth C. May's areas of expertise are International Business, Business Policy and Strategy and International Human Resource Management. Specializing in the transfer of Western management practices to the former Soviet Union, Ruth is currently involved in the development of training programs and privatization processes in central Russia. She has published in the Academy of Management Executive, Multinational Business Review, and Socialist Labor (Russia).  相似文献   
56.
Search and Liquidity in Single-Family Housing   总被引:5,自引:0,他引:5  
A two-stage least squares model of housing prices is estimated with data collected from 3358 single-family home transactions. The results provide evidence for an optimal marketing period and indicate that a liquidity premium is priced in single-family home sales. Consistent with the hypothesis derived from economic search models, the model shows higher selling prices for houses having longer expected marketing periods. The model also shows a price premium for houses that sell faster than expectations. This effect supports the concept that liquidity is a value-enhancing characteristic.  相似文献   
57.
Empirical studies provide compelling evidence that economic agents do not adopt the complete range of energy-efficient technologies that are cost-effective under prevailing prices and market conditions. Analysts commonly attribute this anomaly to the use of high discount rates in energy-related decisions-an interpretation that is difficult to reconcile with standard models of rational choice. This paper recasts the controversy from the perspective of economic theory and finds that market failures related to asymmetric information, bounded rationality, and transaction costs are major contributors to the so-called "efficiency gap."  相似文献   
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Regime Shifts in Asian Equity and Real Estate Markets   总被引:4,自引:0,他引:4  
This paper applies a new statistical technology for identifying regime shifts to analyze recent data on real estate and equity markets in eight developing Far Eastern countries in the 1992–1998 time period. We find that regime shifts in volatility occur in the summer of 1997; however, most of the regime shifts in returns occur in the spring of 1998. While the clustering of regime breaks does not seem to follow any obvious pattern, the country's exposure to trade and firm leverage are important. An analysis of Granger causality suggests that, in most cases, equity returns cause real estate returns but the converse is not true. We also find two-way causality in volatility, suggesting that a common factor drives volatility in these markets. Finally, we provide evidence that the regime shifts generally imply higher relative risk for real estate securities after the estimated breaks.  相似文献   
60.
Recent studies examining the relationship between stock returns and exchange rate changes have provided evidence that the exchange rate exposure of non-financial companies is reduced by the use of foreign exchange derivatives. Building on such research, this study investigates whether past ineffective derivative hedging contributes to explaining future derivatives use. To the extent that companies monitor the effectiveness of their currency risk management practices, past ineffective hedgers can be expected to modify their future use of foreign exchange derivatives accordingly. In our study of 94 non-financial US multinationals, we provide evidence that the change in derivatives use from 1996–1998 to 1998–2000 can be explained in part by the ineffective hedging of currency risk in 1996–1998, controlling for variables associated with theories of optimal hedging. Additional analyses confirm that such primary results are robust to firm size, the level of foreign operations, and the use of derivatives to partially hedge currency risk. Our results imply that as exchange markets and risk management practices change, the use of derivatives to manage exchange rate risk also changes. Our contribution to this field of study is that we find evidence that past ineffective hedgers tend to increase their future use of FXDs.  相似文献   
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