首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1578篇
  免费   85篇
财政金融   214篇
工业经济   82篇
计划管理   326篇
经济学   438篇
综合类   13篇
运输经济   22篇
旅游经济   34篇
贸易经济   360篇
农业经济   71篇
经济概况   94篇
邮电经济   9篇
  2024年   1篇
  2023年   30篇
  2022年   13篇
  2021年   30篇
  2020年   60篇
  2019年   99篇
  2018年   92篇
  2017年   103篇
  2016年   98篇
  2015年   61篇
  2014年   77篇
  2013年   226篇
  2012年   83篇
  2011年   101篇
  2010年   81篇
  2009年   75篇
  2008年   58篇
  2007年   64篇
  2006年   36篇
  2005年   28篇
  2004年   39篇
  2003年   29篇
  2002年   27篇
  2001年   24篇
  2000年   18篇
  1999年   16篇
  1998年   12篇
  1997年   13篇
  1996年   11篇
  1995年   7篇
  1994年   6篇
  1993年   8篇
  1992年   1篇
  1991年   3篇
  1990年   2篇
  1989年   3篇
  1988年   3篇
  1987年   1篇
  1986年   1篇
  1985年   4篇
  1984年   2篇
  1983年   1篇
  1982年   1篇
  1981年   3篇
  1980年   3篇
  1979年   3篇
  1978年   2篇
  1977年   1篇
  1974年   2篇
  1971年   1篇
排序方式: 共有1663条查询结果,搜索用时 15 毫秒
71.
We study the optimal timing of adoption of a cleaner technology and its effects on the rate of growth of an economy in the context of an AK endogenous growth model. We show that the results depend upon the behavior of the marginal utility of environmental quality with respect to consumption. When it is increasing, we derive the capital level at the optimal timing of adoption. We show that this capital threshold is independent of the initial conditions on the stock of capital, implying that capital-poor countries tend to take longer to adopt. Also, country-specific characteristics, as the existence of high barriers to adoption, may lead to different capital thresholds for different countries. If the marginal utility of environmental quality decreases with consumption, a country should never delay adoption; the optimal policy is either to adopt immediately or, if adoption costs are “too high”, to never adopt. The policy implications of these results are discussed in the context of the international debate surrounding the environmental political agenda.   相似文献   
72.
We argue that in seeking to insure against model uncertainty, monetary policy makers are often ready to trade ex post performance for greater certainty in the outcome. They thus look for rules that although not optimal ex post, have certain properties that qualify them as robust. We apply first, Gul's approach of ‘disappointment’ aversion to describe policy makers' aversion to uncertainty and then define the properties the notion of ‘robustness’ entails. With these two tools we then link the desirability of such robust rules to the degree of policy makers' aversion to uncertainty. We thus show that provided such robust rules exist, a larger degree of disappointment aversion leads to a greater emphasis on robustness in policy implementation.  相似文献   
73.
Europe and global imbalances   总被引:2,自引:1,他引:2  
  相似文献   
74.
Aims: Although several therapeutic options are available for chronic immune thrombocytopenic purpura (cITP), little is known about the treatment of cITP in Brazil.

Materials and methods: A multi-center, retrospective chart review, observational study was designed to describe the treatment patterns, clinical burden, resources use, and associated costs for adult patients diagnosed with cITP and treated in public and private institutions in Brazil. Patient charts were screened in reverse chronological order based on their last visit post January 1, 2012. (All costs were calculated using 1.00 USD?=?3.9571 BRL, from February 2016.)

Results: Of 340 patient charts screened, 50 patients were eligible for inclusion in the study. Single-drug therapy (prednisone, dexamethasone, or dapsone) was the most commonly used treatment, followed by combination therapies (azathioprine?+?prednisone, azathioprine?+?prednisone?+?danazol, and prednisone?+?dapsone). Splenectomy was performed in 22% of patients after at least first-line treatment. Platelet count and number of bleeding episodes at diagnosis were 31,561.1/mm3 (SD?=?±26,396.1) and 40 episodes, respectively; in first-line, 92,631.1/mm3 (SD?=?±79,955.3) and 19 episodes, respectively; in second-line, 96,950.0/mm3 (SD?=?±76,476.4) and 17 episodes, respectively. Private system patients had a higher median cost compared to public system patients (USD 17.49/month, range?=?0–2,020.77 vs USD 9.51/month, range?=?0–192.64, respectively).

Limitations: This study does not allow conclusions for causal explanations due to the cohort study design, and treatment patterns represent only the practices of physicians who have agreed to participate in the study.

Conclusions: The data indicate that available therapeutic strategies for second- and third-line therapies appear to be limited.  相似文献   
75.
Using quarterly data for a panel of advanced economies, we show that synchronized fiscal consolidation (stimulus) programmes in different countries make their business cycles more closely linked. We also find: (i) some evidence of decoupling when an inflation targeting regime is unilaterally adopted; (ii) an increase in business cycle synchronization when countries fix their exchange rates and become members of a monetary union; (iii) a positive effect of bilateral trade on the synchronization of business cycles. Global factors, such as a rise in global risk aversion and uncertainty and a reversal of nonstandard expansionary monetary policy, can also reduce the degree of co‐movement of business cycles across countries. From a policy perspective, our work shows that an inflation targeting regime coupled with simultaneous fiscal consolidations can lead to more business cycle synchronization.  相似文献   
76.
In this paper empirical evidence is presented on theelasticity of private R & D spending on its price. Acensored panel-data regression model with random effectsis applied to a balanced panel of 726 Italian firms overthe 1992–1997 period. Implied estimates point out thatItalian firms' response to policy measures (including taxcredits), aimed at reducing the user cost of R & D capital,is likely to be substantial (1.50–1.77). Furthermore, wealso find that the elasticity of R & D spending is higherin recession (2.01) than in expansion (0.87).  相似文献   
77.
In this paper, we model the dynamics of business investment taking into account asset-specific characteristics potentially affecting the reactivity of aggregate and disaggregate capital accumulation over the business cycle. We estimate Information and Communication Technologies (ICTs) and traditional investment (non-ICT) determinants within a Vector Error Correction Model testing the assumptions of the flexible accelerator and neoclassical model as well as the role of financial constraints and uncertainty. We evaluate our model on Italian data over the period 1980–2012, and we check our results also with Spanish and UK data. Our findings support the assumption that capital is heterogeneous since short- and long-run determinants are significantly different across the assets. Traditional assets experience stock adjustment costs while ICT investment incurs flow adjustment cost. In the short run, liquidity is a key determinant of investment independently of the asset type. In the long run, uncertainty significantly affects ICT. Finally, the results of the counterfactual exercises support the idea that ICT is a key policy variable to foster economic growth.  相似文献   
78.
Health insurance reform in Massachusetts lowered the cost of both pregnancy (by increased coverage of pregnancy‐related medical events) and pregnancy prevention (by increasing access to reliable contraception). We empirically examine fertility responses and find no overall effect from increased coverage due to the Massachusetts reform. This finding, however, masks substantial heterogeneity. For married women aged 20 to 34—with high latent fertility and pregnancy wantedness—fertility increased by approximately 1%. For unmarried women in the same age range—for whom pregnancies are typically unwanted—fertility declined by 8%. (JEL I13, I18, J13)  相似文献   
79.
Bio-economic modelling has become a useful tool for anticipating the outcomes of policies and technologies before their implementation. Advances in mathematical programming have made it possible to build more comprehensive models. In an overview of recent studies about bio-economic models applied to land-use problems in agriculture and forestry, we evaluated how aspects such as uncertainty, multiple objective functions, system dynamics and time have been incorporated into models. We found that single objective models were more frequently applied at the farm level, while multiple objective modelling has been applied to meet concerns at the landscape level. Among the objectives, social aspects are seldom represented in all models, when being compared to economic and environmental aspects. The integration of uncertainty is occasionally a topic, while stochastic approaches are more frequently applied than non-stochastic robust methods. Most multiple-objective models do not integrate uncertainty or sequential decision making. Static approaches continue to be more recurrent than truly dynamic models. Even though integrating multiple aspects may enhance our understanding of a system; it involves a tradeoff between complexity and robustness of the results obtained. Land-use models have to address this balance between complexity and robustness in order to evolve towards robust multiple-objective spatial optimization as a prerequisite to achieve sustainability goals.  相似文献   
80.
This study examines the effects of macroeconomic shocks on key macro variables, including stock market returns in Korea, using the structural vector autoregression (SVAR) model. We suggest a three-variable SVAR model incorporating inflation, output growth and stock returns. We adopt a nonzero z-ratio restriction for the long-run identifying assumption to allow for economically meaningful relationships among variables. While our results support the negative (positive) relation of demand (supply) shocks to stock returns, we also find that demand shocks influence stock market variance more significantly than supply shocks do. The sub-period analysis finds that global market fluctuations during the global financial crisis have relatively little effect on Korean stock market performance. We also examine a generalized five-variable model that includes the foreign exchange rate and interest rate, confirming the results from the three-variable case.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号