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941.
Abstract

Background: The prevalence of nontuberculous mycobacterial lung disease (NTMLD) in the US has increased; however, data characterizing the associated healthcare utilization and expenditure at the national level are limited.

Objective: To examine associations between economic outcomes and the use of anti-Mycobacterium avium complex (MAC) guidelines-based treatment (GBT) for newly-diagnosed NTMLD in a US national managed care claims database (Optum® Clinformatics® Data Mart).

Methods: NTMLD was defined as having ≥2 claims for NTMLD (ICD-9 031.0; ICD-10 A31.0) on separate occasions ≥30?days apart (between 2007 and 2016). The cohort included patients insured continuously over a period of at least 36?months (12?months before initial NTMLD diagnostic claim and for the subsequent 24?months). Treatment was classified as GBT (consistent with American Thoracic Society/Infectious Diseases Society of America guidelines), non-GBT, or untreated. All-cause hospitalization rates and total healthcare expenditures at Year 2 were assessed as outcomes of the treatment prescribed in Year 1 after NTMLD diagnosis.

Results: A total of 1,039 patients met study criteria for NTMLD (GBT, n?=?294; non-GBT, n?=?298; untreated, n?=?447). After adjustment for baseline characteristics, GBT was associated with a significantly lower all-cause hospitalization risk vs non-GBT (odds ratio [OR]?=?0.53; 95% CI = 0.33–0.85, p?=?0.008), and vs being untreated (OR = 0.57; 95% CI = 0.35–0.91, p?=?0.020). Adjusted total healthcare expenditure in Year 2 with GBT ($69,691) was lower than that with non-GBT ($77,624) with a difference of ?$7,933 (95% CI = ?$14,968 to ?$899; p?=?0.03).

Conclusions: Patients with NTMLD in a US managed care claims database who were prescribed GBT had lower hospitalization risk than those who were prescribed non-GBT or were untreated. GBT was associated with lower total healthcare expenditure compared with non-GBT.  相似文献   
942.
Abstract

Background:

Tiotropium has been shown to reduce exacerbations and improve quality of life for patients with chronic obstructive pulmonary disease (COPD), a lung disease characterized by a persistent and progressive airflow limitation.

Objectives:

To present a systematic literature review of the cost effectiveness of treatment with tiotropium compared with other currently used treatments for COPD.

Methods:

A systematic search was performed via PubMed, the Cochrane database, and EMBASE from 2002 to 2009. Methods and results by study design and by country were compared.

Results:

Seventeen studies were included in the review. Study designs were characterized as follows: modeling based on clinical trial data, and empirical analysis based on either clinical trial or observational data. Comparing monotherapy regimens (12 studies), all study designs found that treatment with tiotropium was associated with lower costs for hospitalisation and other non-drug services. Total costs, including the costs of maintenance drugs, were lower with tiotropium in some, but not all, of the studies. Tiotropium was shown to be cost effective based on commonly accepted benchmark values. Limitations of the review included the wide variety of outcome measures used in different studies, the limited number of observational database studies for monotherapy, and limited data for combination therapy regimens.

Conclusions:

The main conclusions of the economic evaluations derived from clinical trial data at the time of product approval and from later observational data reflecting clinical use are similar: use of tiotropium monotherapy is associated with lower hospital and other non-drug costs and better health outcomes and is either cost saving or cost effective compared with other maintenance monotherapies.  相似文献   
943.
目的比较维格列汀、吡格列酮、格列美脲分别与二甲双胍合用治疗2型糖尿病时的效果、成本及成本-效果。方法运用Markov模型对三种治疗方案的终身治疗成本及效用(期望寿命、质量调整寿命年)进行经济学评价,通过文献资料和专家问卷咨询获得临床、生命质量、并发症年治疗成本等数据,进行敏感度分析。结果维格列汀、吡格列酮、格列美脲分别与二甲双胍合用治疗2型糖尿病分别延长11.02、10.96、10.90个质量调整生命年,而生命周期中三种治疗方案的治疗费用分别为124892元、134135元、126010元。敏感度分析证明了结果的可靠性。结论与吡格列酮、格列美脲合并二甲双胍质量相比,维格列汀合并二甲双胍治疗获得的健康效果更好,而治疗成本更低。  相似文献   
944.
摘要:新型农村养老保险制度的实施和持续发展,不仅具有维护农村居民社会养老保险权益公平性的社会作用,还能起到刺激农村消费需求增加从而促进农村经济发展的经济作用。通过两期代际扩展型的应用,证明了新农保的实施对个体农户终身效用最大化下的最优储蓄存在挤出效应,其主要影响因素有:缴费年限、缴费比率、养老保险账户的增值保值能力和收入替代率等,并以此为基础,提出了完善新农保制度、促进其可持续发展的政策建议。  相似文献   
945.
The present study analyzes the influence that perceived risk in online shopping has on the process of e‐commerce adoption by end consumers. With this aim, the Technology Acceptance Model is taken as a reference framework, proposing an Extended E‐Commerce Acceptance Model that includes the diverse constructs of perceived risk: financial, performance, social, time, psychological and privacy. Empirical evidence is obtained from two samples, one is composed by Internet users with no experience in web shopping and the other is formed by online buyers. The results obtained confirm that the intention to shop through the Internet is positively influenced by general attitude toward the system and negatively influenced by the risk associated with the Web. Regarding the importance of the risk dimensions considered in the study, the economic and performance facets are the ones that have a greater influence on e‐commerce adoption, while social and time dimensions are the less relevant.  相似文献   
946.
In this paper, we develop a multivariate risk-neutral Lévy process model and discuss its applicability in the context of the volatility smile of multiple assets. Our formulation is based upon a linear combination of independent univariate Lévy processes and can easily be calibrated to a set of one-dimensional marginal distributions and a given linear correlation matrix. We derive conditions for our formulation and the associated calibration procedure to be well-defined and provide some examples associated with particular Lévy processes permitting a closed-form characteristic function. Numerical results of the option premiums on three currencies are presented to illustrate the effectiveness of our formulation with different linear correlation structures.  相似文献   
947.
We consider robust optimal portfolio problems for markets modeled by (possibly non-Markovian) Itô–Lévy processes. Mathematically, the situation can be described as a stochastic differential game, where one of the players (the agent) is trying to find the portfolio that maximizes the utility of her terminal wealth, while the other player (“the market”) is controlling some of the unknown parameters of the market (e.g., the underlying probability measure, representing a model uncertainty problem) and is trying to minimize this maximal utility of the agent. This leads to a worst case scenario control problem for the agent. In the Markovian case, such problems can be studied using the Hamilton–Jacobi–Bellman–Isaacs (HJBI) equation, but these methods do not work in the non-Markovian case. We approach the problem by transforming it into a stochastic differential game for backward stochastic differential equations (a BSDE game). Using comparison theorems for BSDEs with jumps we arrive at criteria for the solution of such games in the form of a kind of non-Markovian analogue of the HJBI equation. The results are illustrated by examples.  相似文献   
948.
In March 2008, the Australian Government announced its intention to introduce a national Emissions Trading Scheme (ETS), now expected to start in 2015. This impending development provides an ideal setting to investigate the impact an ETS in Australia will have on the market valuation of Australian Securities Exchange (ASX) firms. This is the first empirical study into the pricing effects of the ETS in Australia. Primarily, we hypothesize that firm value will be negatively related to a firm's carbon intensity profile. That is, there will be a greater impact on firm value for high carbon emitters in the period prior (2007) to the introduction of the ETS, whether for reasons relating to the existence of unbooked liabilities associated with future compliance and/or abatement costs, or for reasons relating to reduced future earnings. Using a sample of 58 Australian listed firms (constrained by the current availability of emissions data) which comprise larger, more profitable and less risky listed Australian firms, we first undertake an event study focusing on five distinct information events argued to impact the probability of the proposed ETS being enacted. Here, we find direct evidence that the capital market is indeed pricing the proposed ETS. Second, using a modified version of the Ohlson ( 1995 ) valuation model, we undertake a valuation analysis designed not only to complement the event study results, but more importantly to provide insights into the capital market's assessment of the magnitude of the economic impact of the proposed ETS as reflected in market capitalization. Here, our results show that the market assesses the most carbon intensive sample firms a market value decrement relative to other sample firms of between 7% and 10% of market capitalization. Further, based on the carbon emission profile of the sample firms we imply a ‘future carbon permit price’ of between AUD$17 per tonne and AUD$26 per tonne of carbon dioxide emitted. This study is more precise than industry reports, which set a carbon price of between AUD$15 to AUD$74 per tonne.  相似文献   
949.
The main reasons for giving European insurance companies the option to apply internal models for calculating the main solvency requirement within the Solvency II framework is to enhance better risk management in the firms, and to provide the opportunity to derive a more accurate risk-oriented capital requirement than the standard Solvency Capital Requirement (SCR) could provide. The possibility to use internal models within pillar 1 basically means freedom to calculate the solvency requirement using some other formula and even principles than those given by the standard formula. This freedom is more limited with partial models.

This paper gives a brief introduction and update to the Solvency II project, reviews and discusses some topical aspects of internal models from the supervisory point of view, and points out some relating results of the Quantitative Impact Studies carried out, thus far, in the EU by CEIOPS.  相似文献   
950.
In the framework of classical risk theory we investigate a model that allows for dividend payments according to a time-dependent linear barrier strategy. Partial integro-differential equations for Gerber and Shiu's discounted penalty function and for the moment generating function of the discounted sum of dividend payments are derived, which generalizes several recent results. Explicit expressions for the nth moment of the discounted sum of dividend payments and for the joint Laplace transform of the time to ruin and the surplus prior to ruin are derived for exponentially distributed claim amounts.  相似文献   
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