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161.
明代宫廷的书画收藏十分丰富,嘉靖以后虽多有散出,但仍具有一定规模,直至明清鼎革之际宫廷所藏书画才散佚殆尽。明代宫廷所藏书画主要包括接收前代遗存、查抄籍没书画以及帝后臣工新创作书画几个部分。宫廷所藏书画主要由宦官机构司礼监负责保管,存放于质慎库中;另有部分历代帝王、君臣画像由印绶监保管,存放于古今通集库中。明代中叶以后,宫廷收藏书画通过充抵官员俸禄、偷窃等方式大量流散出宫,但同时也存在一定的补充和回流。明清易代之际,宫中所藏书画散佚殆尽,这为明末清初私人收藏家群体的崛起提供了机遇。  相似文献   
162.
由于长期的城乡二元体制,我国农村养老事业的发展远落后于城市,农村养老政策的欠完善成为影响农村养老问题解决的重要因素.回顾新中国成立以来我国农村养老政策的发展历程,将其分为萌芽时期、转型时期和发展时期三个发展阶段,并重点分析了五保供养制度、农村养老保险制度、农村合作医疗制度、最低生活保障制度等特殊养老制度,在此基础上提出了农村养老政策的未来展望.  相似文献   
163.
164.
Previous research has shown that there are a number of risk factors for disordered and problem gambling, including an individual’s ethnicity and age. Endorsing gambling as an escape has also been shown to contribute to and maintain disordered gambling. The present study examined potential interactions between ethnicity and age as they relate to disordered gambling, as well as if ethnicity and age would be predictors of endorsing gambling as an escape. Three hundred fifteen adults from the United States completed measures relating to gambling. Participants were grouped into ethnic categories of Caucasian and non-Caucasian, and age groups of 18–25, 26–35, 36–55, and 56 years old and above. Non-Caucasians reported more gambling problems than Caucasians. A significant interaction was found between ethnicity and age for 36–55 year olds. Overall, participants were more likely to gamble for positive than negative reinforcement. However, only gambling as an escape was a significant predictor of disordered gambling. Implications and limitations are discussed with the thought that these results are informative to practitioners treating disordered gambling.  相似文献   
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166.
In this article, we generalize the partially linear single-index models to the scenario with some endogenous covariates variables. It is well known that the estimators based on the existing methods are often inconsistent because of the endogeneity of covariates. To deal with the endogenous variables, we introduce some auxiliary instrumental variables. A three-stage estimation procedure is proposed for partially linear single-index instrumental variables models. The first stage is to obtain a linear projection of endogenous variables on a set of instrumental variables, the second stage is to estimate the link function by using local linear smoother for given constant parameters, and the last stage is to obtain the estimators of constant parameters based on the estimating equation. Asymptotic normality is established for the proposed estimators. Some simulation studies are undertaken to assess the finite sample performance of the proposed estimation procedure.  相似文献   
167.
To compare two modes of administration (self-administered; by interviewer) and two response options format (using words; images of “facial-expressions”) of the first question of SF-36 (Q1SF-36), and to test its validity. We included 825 participants (20–90 years). Q1SF-36, using words or images, was included in a global questionnaire interview and at the end participants filled the SF-36. The agreement was tested by weighted kappa coefficients (WKappa). Classification Trees were used in the calibration of Q1SF-36 responses, with the physical (PDSF36) and mental dimensions of SF-36. Polyserial correlation coefficients and areas under the ROC curves (AUC) were used for validation. After categorization, using PDSF36 classification trees, the WKappa were 0.770 (self-administered vs. interviewer), 0.569 (self-administered vs. facial-expressions) and 0.566 (interviewer vs. facial-expressions). The WKappa between the PDSF36 and the modes (self-administered, interviewer and facial-expressions) were 0.784, 0.713 and 0.579 and the corresponding polyserial correlation coefficients were 0.784, 0.713 and 0.579. A good discriminatory power was found comparing the modes with the PDSF36 (AUC = 0.907, 0.923 and 0.827), but not with mental dimension (AUC = 0.538, 0.501 and 0.629). The Q1SF-36, by self-administration or interviewer, may be a valid alternative for assessment of subjective physical health, but not mental health.  相似文献   
168.
169.
Social service contracting to nongovernmental organizations is popular form of privatization across the world. Although nonprofits are preferable social service providers for legal and normative reasons, governments in the United States increasingly rely on for-profit organizations to deliver social services. This trend warrants further exploration about whether nonprofits or for-profits perform according to theoretical expectations when they exist in the same market. This study employs qualitative comparative analysis (QCA) to examine how sector-public, nonprofit, and for-profit-combines with structural variables to produce acceptable contract performance in juvenile justice programs. QCA is a discovery-oriented research tool that determines whether combinations of variables within cases produce a specific outcome and whether those combinations are consistent across cases. I find sector is not a necessary or sufficient predictor of acceptable performance on its own. Rather it combines with market factors to lead to acceptable contract performance. Combinations vary by sector, indicating that sectors behave differently in similar circumstances. The primary theoretical contribution of this paper is to provide a nuanced account of contract performance in mixed sector markets.  相似文献   
170.
We critically review conceptual and empirical issues surrounding the derivation of the international poverty line, expressed in PPP-adjusted dollars and linked to various rounds of the International Comparison Program (ICP). We find that there are some limitations in the current estimation of these lines, but show that statistically superior methods lead to lines that are relatively robust and confirm the $1.25 using 2005 PPPs and suggest $1.67–1.71 using 2011 PPPs (or close to the $1.90 proposed by the World Bank if we follow the World Bank’s approach of adjusting inflation rates in some countries); they also roughly confirm the current shape of the proposed ‘weakly relative’ poverty line. Using the new absolute line based on 2011 PPPs would lead to substantially lower poverty in our estimation. The extent of the decline depends on whether and how one treats China, India, and Indonesia differently from other countries in the 2005 and 2011 PPPs. More seriously, we note that the dependence on successive ICP rounds creates conceptual and empirical problems that have become worse over time so that we suggest that it would be best to consider alternatives to the current reliance on ICP rounds and the resulting PPPs. As a short-term solution we propose to fix the international poverty line in national currencies using either the 2005 or 2011 level; in the medium term, we argue for global poverty measurement based on internationally coordinated national poverty measurement.  相似文献   
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