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51.
Objective: To review, summarize, and analyze both similarities and differences of pharmacoeconomic (PE) guidelines, to enable researchers to access their characteristics and the current state of PE guidelines; furthermore, to learn which methodological issues still remain contested and to promote the methodological development of PE guidelines.

Materials and methods: The authors performed a search for PE guidelines using PubMed, the Cochrane library database, and the websites of the International Society for Pharmacoeconomics and Outcomes Research. Information of each guideline was extracted using a pre-designed extraction template, which included 22 aspects; the guidelines were summarized in the forms of charts, and their characteristics have been described.

Results: A total of 40 PE guidelines were studied. The most common methodological issues include the types of analysis, sources for effectiveness, use of quality-adjusted life-years (QALYs) to measure outcomes, and use of incremental cost effectiveness ratios to present results. The majority of the guidelines preferred a cost utility analysis with outcomes expressed in terms of QALYs. Most of the guidelines preferred meta-analysis or meta-analysis of the randomized controlled trials, and required a systematic review of all evidence. Issues that varied most in the guidelines were the choice of the comparator, recommended costs to be included, methods related to indirect cost calculations, methods of sensitivity analysis, and discounting rate.

Conclusion: A comparison of these guidelines revealed that a number of differences exist among them in several key aspects, and some critical methodological issues still exist, for which no best solution is available. Furthermore, efforts need to be made to develop harmonious methods for the PE, and to improve the transferability of the outcomes of PE evaluations.  相似文献   
52.
中国耕地资源利用的碳排放时空特征及脱钩效应研究   总被引:8,自引:0,他引:8  
研究目的:揭示中国耕地资源利用的碳排放时空分异规律及其与农业经济增长之间的脱钩关系,以期为中国耕地资源低碳化利用政策的制定和推行提供参考。研究方法:IPCC碳排系数法,TAPIO脱钩分析法。研究结果:(1)中国耕地资源利用的碳排放整体上呈现增长趋势,但2010年后增速趋于下降并于2016年开始转入负增长,省际差异不断扩大的同时区域间差异趋于缩小;(2)中国耕地资源利用的碳排放强度总体上处于下降态势,省际和区域间碳排放强度的差异总体上趋于缩小;(3)中国耕地资源利用的不同碳排放源的碳排放量及增速呈现不同的时序波动特征,同时存在明显的地域差异性,其中,化肥是最主要碳排放源;(4)中国2000—2012年耕地资源利用的碳排放与农业经济增长之间呈现以"弱脱钩"为主,但2013—2017年不同省域的脱钩类型及脱钩程度趋于差异化。研究结论:中国耕地资源利用碳排放的时空分异性显著,且与农业经济增长之间不同阶段和不同省域呈现不同脱钩类型,需突出减排重点、实施差异化策略及注重绿色发展等多途径推进耕地资源低碳化利用,提高政策的精准性。  相似文献   
53.
Payments for ecosystem services (PES) are environmental management tools that enable corporations to simultaneously enhance their environmental performance and fund sustainable development in rural areas. PES is primarily promoted as part of a sustainable production strategy for conserving natural resources, offsetting carbon emissions, and green supply chain management. Nevertheless, PES uptake by the private sector remains low, and few studies have analysed whether corporate‐financed PES schemes conform to this rationale. This study evaluates three of the first PES schemes in Thailand, financed by large corporations in the water utilities, aquaculture, and beverage sectors. Interviews with 39 business managers and project stakeholders suggest that PES may be viewed as a tool for philanthropy, public relations, and gaining license to operate—akin to many corporate social responsibility initiatives. Explanations and ramifications are discussed in the context of ecological uncertainty, risk management, financial performance, organisational learning, and the corporate‐engagement strategies of non‐governmental organisations.  相似文献   
54.
稻鳅共生种养模式试验研究   总被引:2,自引:0,他引:2  
[目的]稻鳅共生是典型的稻田综合利用模式,符合生态农业发展方向。通过对稻鳅共生生态系统的生理生态学机制开展试验研究,为进一步推广稻鳅共生种养模式提供科学依据。[方法]采用田间试验方法,以水稻单作为对照,研究了不同泥鳅养殖密度下的稻鳅共生对水稻农艺性状、土壤理化性质、水稻产量构成的影响,并对稻鳅共生种养模式进行了经济效益分析。[结果]与对照处理相比,水稻长势在株高、有效分蘖率、根长等方面有一定提高。养殖田水稻株高增高了3%,有效分蘖率提高了8%~11%,根长提高了8.8%~31.3%。在土壤理化性质方面,与对照相比,土壤容重降低了7.1%~21.2%,孔隙度增加了4.1%~14.7%。实验前后养殖田内土壤有机质增加了3.5%~26.5%,对照田降低了2.5%~5.8%。土壤肥力(氮、磷、钾)减少,但减少幅度小于对照处理。稻鳅共生种养模式下水稻产量提高了5%~25%,同时稻田增收泥鳅1 725~3 375kg/hm2,净收入为1.836 0万~2.307 0万元/hm2,经济效益提高了3.65~4.84倍。稻鳅共生种养模式中泥鳅的养殖密度为30万尾/hm2时稻田的生态效益和经济效益最佳。[结论]稻鳅共生有效改善了土壤理化性质,促进了水稻的生长,提高了稻田产量和产值。  相似文献   
55.
基于管理规范、管理执行、管理支持和管理效益4个方面的指标构建,对中国181个国家水利风景区进行问卷调查,以评价水利风景区的管理效能。结果表明:181个水利风景区管理效能平均得分为58.4分,得分低于60分的水利风景区占54.7%,说明我国水利风景区的管理效能总体偏低;水利风景区管理效能与景区类型、批准设立时间、地域分布、所在地区域经济发展水平、主要功能、管理机构独立性差异显著,与面积大小和经营性质之间差异不显著。从分类指标看,管理效果类指标得分最低,从全部指标看,土地权属、游客控制、餐住布局、管理条例、环境保护考核、生态厕所、居民参与、资源调查、保护经费、环境保护宣传、环境保护培训、经营情况等10个指标得分低于平均分。建议破除管理体制障碍,实行分类管理,试点跨流域、市场化、多功能间生态补偿制度,实行特许经营制度,加强自然保护地监督管理,完善自然保护地制度体系。  相似文献   
56.
闽侯县闲置农地生态安全评价研究   总被引:1,自引:0,他引:1  
[目的]根据闽侯县农用地闲置情况,结合当地社会经济及生态环境发展情况,深入分析闽侯县闲置农地的生态安全发展水平。[方法]建立闽侯县闲置农地生态安全评价指标体系,分别从农村垃圾处理点数量、财政支农资金、外部进入农村投资、农业生产总值、种粮补贴、自然灾害、农业技术水平、农村生物的多样性程度、农村家庭收入结构、农村生态补偿金额、农地的整理规模及环保支出占GDP比重共确定12个指标进行深入研究,运用普通最小二乘法对设计的多元线性回归模型进行回归,进一步对闽侯县闲置农地的生态安全水平进行评价。[结果]农村垃圾处理点数量、财政支农资金、种粮补贴、环保支出占GDP比重、生态补偿金额、生物多样性程度对闽侯县闲置农地生态安全水平起到促进作用,呈正相关趋势;自然灾害则与闲置农地生态安全水平呈负相关趋势。[结论]整体看来,闽侯县闲置农地的生态安全水平主要受到当地经济、环境及生态基础三大因素的影响。  相似文献   
57.
Farmers in the Vietnamese Mekong Delta face a wide range of climate-related and hydrological factors which threaten rice production. Smallholder farmers must adapt to climate change to sustain rice production as their central and most important livelihood activity. A sample was stratified across agro-ecological areas in the Delta affected by flooding, alluvial soils, acid sulphate soils, and saline water intrusion and by derived farmer typologies. A rural livelihoods approach was used in focus group discussions and in-depth interviews to identify and enumerate enabling and constraining adaptation factors. Smallholders experienced diverse natural hazards such as floods, abnormal rains, high temperatures, water scarcity, and salinity intrusion specific to the agro-ecological areas. Adaptation was constrained by labour shortages, water quality, topography, access to combine harvesters, transportation infrastructure, dryers and household savings. Adaptation was enabled by farming techniques and experience, cooperative groups, water quantity, access to information, and ability to purchase agro-chemicals through credit. Small farmers (< 1?ha) were more constrained than large farmers (> 1?ha) who had an expanded livelihood asset base. A range of policy implications are discussed, but adaptation is not just about technological fixes but requires overall improvements in a range of human, social and financial components.  相似文献   
58.
Unlike previous studies in which a single index was used to measure audit quality, this study establishes a new comprehensive index to measure audit quality via Discretionary Accrual, as estimated by Jones’ basic model (1991) and Audit Opinions. The former is used to measure the quality of financial statements, and the latter is used to measure the auditors’ independence in the mainstream international literature. We examine whether and how an auditor’s gender affects the quality of his or her audits under the framework of empathy theory and gender role socialization theory. Using a large sample of 9861 auditor-firm-year observations from Chinese A-share–listed companies from 2011 to 2015, we find that the audit quality of signed auditors shows significant gender differences: these significant gender differences differ from the findings of previous studies that female auditors could provide a higher-quality audit than male auditors; that is, in our study the audit quality of the male auditors exceeds that of the female auditors. After distinguishing the positive and negative directions of the Discretionary Accrual, we find no significant gender differences in audit quality between male and female auditors when the earnings had been adjusted upward by the client; that is, female and male auditors had the same audit risk perception. However, when the client adjusted earnings downward, which indicates a lower audit risk for the auditor, the audit quality of female auditors was significantly lower than that of the male auditors. After controlling for the age and position of the auditors, we also find that the gender differences in the auditors’ audit quality decreased significantly or even disappeared when the auditor’s age exceeded 45?years and/or their position was manager or above. These results are consistent with the empathy theory and gender role socialization theory.  相似文献   
59.
新型冠状病毒感染的肺炎疫情发生以来,全国上下齐心协力,在中国共产党的集中统一领导下、在以人民为中心的执政理念指引下,依靠集中力量办大事的体制优势、社会主义先进文化的支撑,以及依法治国理念的保障,使疫情在短时间内得到有效控制,最大程度保障了人民的生命安全,集中体现了中国特色社会主义制度的显著优势。  相似文献   
60.
This study examines the extent of and determinants for sustainability assurance quality. Data comprise sustainability assurance statements published by the top 100 listed companies in Australia and New Zealand from 2017 to 2019. The findings indicate that Australian companies lead their New Zealand counterparts in sustainability assurance. Although sustainability reporting has risen, assurance rates remain significantly low. Accountants dominate the market, and companies prefer to use their own auditors for sustainability assurance work. Sustainability assurance quality is poor and does not vary significantly among Australian and New Zealand companies. Low-quality sustainability assurance plays a limited role in mitigating potential stakeholder–agency conflicts. The regression analysis indicates that audit committee characteristics such as members' independence, industry/market expertise, and attending meetings enhance sustainability assurance quality, whereas audit committee size has no affect. These findings suggest that audit committee characteristics such as independence, industry expertise, and regular meeting attendance have the potential to reduce stakeholder–agency conflicts by improving the quality of sustainability statement assurance. Our findings build on the sustainability assurance literature by exploring current trends in sustainability assurance practices in Australia and New Zealand where corporate governance codes have been recently revised. Further, these findings are timely given recent changes in standards (International Standard on Assurance Engagements [ISAE] 3000 and Global Reporting Initiative [GRI]). Our study contributes to the audit committee literature and sheds light on the role played by audit committee characteristics on sustainability assurance statement quality. The study findings potentially offer useful insights for practitioners, standard setters, and regulators.  相似文献   
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