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911.
Agricultural policies in sub-Saharan Africa have paid insufficient attention to sustainable intensification. In Uganda, agricultural productivity has stagnated with aggregate increases in crop production being attributed to expansion of cultivated land area. To enhance sustainable crop intensification, the Ugandan Government collaborated with stakeholders to develop agricultural policies using an evidence-based approach. Previously, evidence-based decision-making tended to focus on the evidence base rather than evidence and its interactions within the broader policy context. We identify opportunities and pitfalls to strengthen science engagement in agricultural policy design by analysing the types of evidence required, and how it was shared and used during policy development. Qualitative tools captured stakeholders' perspectives of agricultural policies and their status in the policy cycle. Subsequent multi-level studies identified crop growth constraints and quantified yield gaps which were used to compute the economic analyses of policy options that subsequently contributed to sub-national program planning. The study identified a need to generate relevant evidence within a short time 'window' to influence policy design, power influence by different stakeholders and quality of stakeholder interaction. Opportunities for evidence integration surfaced at random phases of policy development due to researchers’ ’embededness’ within co-management and coordination structures.  相似文献   
912.
This paper contributes to an evaluation of the performance of ground nuts in drought-prone areas by estimating yield response functions to water from experimental data. They are combined with meteorological data to simulate yields by location. Efficient genotypes are identified by several risk criteria. Genotype rankings based on these risk criteria and simulated yields are different from those based on experimental data and plant scientists' traditional methods of evaluation.  相似文献   
913.
914.
The new African National Congress government announced after 1994 that municipal commonage would be a pillar of their land reform programme. The Department of Land Affairs spearheaded this by acquiring new land to complement the existing ‘old’ commonages. The aim of old commonage was to supplement the income of poor urban residents through the subsistence user system whereas new commonage was intended as a ‘stepping stone’ for emergent farmers. We investigated the differences between old and new commonage farmers as well as how they perceived the Makana local municipality's capacity to manage the commonage. The results showed that local institutions were weak. Only 46% of the old commonage farmers were members of a local livestock association whereas 74% of the new commonage farmers were members. Most old commonage farmers (59%) were dissatisfied with local government's management of the commonage. In contrast, only 37% of the new commonage farmers were dissatisfied with the management of the commonage. There were no differences between old and new commonage farmers in terms of livestock owners’ characteristics and mean annual net direct-use value of livestock. There were also no differences in the age of the two types of commonage farmers. Furthermore, there was no association between the type of commonage and level of education. The mean annual net direct-use value of livestock on old commonage was R6308 compared with R9707 on new commonage. Although the income from livestock for new commonage farmers varied slightly from that of old commonage farmers, the annual productive output per farmer on old commonage was R473 ha−1, three times higher than that of new commonage farmers which was R134 ha−1. We suggest that new land policy legislation is needed in which poverty as well as the legal arrangements between all stakeholders is clearly defined. Furthermore, national departments need to be more involved with local municipalities to increase local management capacity.  相似文献   
915.
This article investigates the nonlinear adjustment between consumer and producer prices in the Greek milk sector using a threshold error correction autoregressive model. The results reject the null hypothesis of linear cointegration in favor of a 2-regime threshold cointegration model. A cointegrating relationship is expected only when equilibrium consumer price is decreased more than 24.12% or the equilibrium relative markup is squeezed more than 62.74%. In this case consumer prices have to increase faster than producer prices to restore the long-run equilibrium between consumer-producer milk prices.  相似文献   
916.
This paper proposes an extensive data simulation exercise on the likely impact of non-agricultural market access liberalization. The paper analyses real options for tariff cut reduction, special and differential treatment and the treatment of unbound tariffs. This paper also gives indications concerning the likely economic impact of this trade round of industrial market access negotiations on African economies. It shows that an ambitious tariff cut reduction formula would provide greater access to developed country markets for African producers. However, this kind of formula has a major drawback for African countries in the sense that it could accelerate the de-industrialization of African countries and limit incentives to diversify their economies.  相似文献   
917.
[目的]文章评估了价格支持政策对不同粮食作物播种面积变化的平均效应与动态效应,并测度多种价格支持政策的交叉政策弹性。[方法]基于1998—2016年实施粮食价格支持政策省份面板数据,设立对照组,利用倾向得分匹配—双重差分方法(PSM DID)评估价格支持政策平均效应与动态效应,并构建粮食作物供给反应(Nerlove)模型测度价格支持政策的交叉政策弹性。[结果](1)价格支持政策对水稻、小麦、玉米播种面积增加具有不同程度的推动作用,按大小依次为玉米>水稻>小麦,对大豆播种面积变化影响不显著; (2)价格支持政策持续时间越长,对水稻、玉米播种面积增加的推动作用越大,对小麦播种面积增加的推动作用较为稳定; (3)小麦、玉米播种面积变化主要来自自身价格支持政策,水稻播种面积变化除了受到自身价格支持政策影响外,还受到其他作物政策影响,大豆播种面积变化对玉米临储政策反应敏感,对自身价格支持政策反应不敏感。[结论]在制定粮食政策时既要区分政策及其持续性对不同粮食播种面积变化的影响差异,又要注意在同一地区实施多种粮食政策时,可能对不同作物产生交叉影响。  相似文献   
918.
在金融历史发展过程中,时间、机遇和风险、市场以及企业法人等四个主题是永恒的。大约早在1000年前,金融的各种主要要素便都已经存在了,后来经过逐步发展和成熟,演化成今天无数的金融创新。  相似文献   
919.
We address a previous finding in the business ethics literature in which accounting professionals in higher rank levels, i.e., “manager” or “partner” of auditing firms, appear to have lower moral reasoning ability than their junior counterparts. Prior investigations have relied upon a similar methodology for estimating ethical beliefs, namely testing “moral reasoning ability” using either the Moral Judgment Interview or Defining Issues Test. In the present study, we use a multiple vignettes approach to test for the existence of the inverse rank-ethical beliefs effect. With only 2 of the 30 vignettes resulting in both managers and partners being more accepting of the ethically charged behaviors, the results presented here using this alternative methodology are generally not supportive of the inverse rank-ethical beliefs phenomenon. We also use a multivariate analysis in order to control for demographic characteristics. Our results suggest that the most robust predictor of ethical attitudes among accounting practitioners is age, not rank within a firm.  相似文献   
920.
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