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31.
本文旨在通过提出多媒体教学手段的多种优势以及诸多专家学者的观点,同时谈到笔者在使用多媒体进行外语教学过程中的一些切身体会,进行理论和实践上的论证,以发掘外语教学中利用多媒体教学手段进行创新性“教”与自主性“学”的可能性,并进一步加强学生的自主性学习以及自我调节性学习,使外语教师更加高效地利用多媒体的优势进行理想的外语教学,同时使外语教学手段更加具有开放性和实践性。  相似文献   
32.
第二语言习得和理解的正确率取决于习得者对目的语的了解程度。在学习和使用第二语言时难免会出现这样那样的错误。有时是因为缺乏对目的语的了解而产生的语内差错,有时则是由于母语的干扰而出现的语际差错。对这些错误进行分类和分析,有助于习得者提高对第二语言的学习和应用能力,减少差错率。  相似文献   
33.
文本同声传译材料的语言特点是影响口译质量的一个重要变量.它包括词汇密度高,没有冗长罗嗦成分,较少出现形合现象,句法停顿较多.为提高口译质量,我们建议同声传译大会发言者从发言口语化,多使用意群停顿以及保持适中语速方面做出努力.  相似文献   
34.
命名与语言、民俗、文化及其它学科之间,均有非常密切的关系。通过对命名学的研究,可以使人们科学地利用命名和有关名称,在人类生活的诸多方面也会产生重要的指导意义。  相似文献   
35.
企业改制是建立现代企业制度的必要途径。资产评估是企业改制中必不可少的重要环节。资产评估应明确评估目的、评估基准期、评估对象 ,掌握正确的评估方法和规范的评估程序。在企业改制中要特别注意设计稳妥的剥离方法 ,对非经营性资产和非经营性人员进行合理的剥离  相似文献   
36.
Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern.  相似文献   
37.
根据地方综合性大学的特点,确立外语教师、学生、辅导员三维一体的教学管理模式具有它的可行性。在这个模式中,教师是教学系统稳态的维系力量,学生是外语教学的主体,辅导员对学生外语学习活动起着导向作用。其三者之间是缺一不可的良性互动的辩证关系。  相似文献   
38.
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure.  相似文献   
39.
文学性言外行为与普通交际性语言的言外行为有所不同 ,文学性言外行为的隐蔽性是由于文学标准、作家对社会文化政治情况的考虑、文学符号的艺术性以及作家对读者群定位造成的  相似文献   
40.
This study evaluates the dose-response relationship for inhalation exposure to hexavalent chromium [Cr(VI)] and lung cancer mortality for workers of a chromate production facility, and provides estimates of the carcinogenic potency. The data were analyzed using relative risk and additive risk dose-response models implemented with both Poisson and Cox regression. Potential confounding by birth cohort and smoking prevalence were also assessed. Lifetime cumulative exposure and highest monthly exposure were the dose metrics evaluated. The estimated lifetime additional risk of lung cancer mortality associated with 45 years of occupational exposure to 1 microg/m3 Cr(VI) (occupational exposure unit risk) was 0.00205 (90%CI: 0.00134, 0.00291) for the relative risk model and 0.00216 (90%CI: 0.00143, 0.00302) for the additive risk model assuming a linear dose response for cumulative exposure with a five-year lag. Extrapolating these findings to a continuous (e.g., environmental) exposure scenario yielded an environmental unit risk of 0.00978 (90%CI: 0.00640, 0.0138) for the relative risk model [e.g., a cancer slope factor of 34 (mg/kg-day)-1] and 0.0125 (90%CI: 0.00833, 0.0175) for the additive risk model. The relative risk model is preferred because it is more consistent with the expected trend for lung cancer risk with age. Based on statistical tests for exposure-related trend, there was no statistically significant increased lung cancer risk below lifetime cumulative occupational exposures of 1.0 mg-yr/m3, and no excess risk for workers whose highest average monthly exposure did not exceed the current Permissible Exposure Limit (52 microg/m3). It is acknowledged that this study had limited power to detect increases at these low exposure levels. These cancer potency estimates are comparable to those developed by U.S. regulatory agencies and should be useful for assessing the potential cancer hazard associated with inhaled Cr(VI).  相似文献   
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