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21.
从文明交往看巴以冲突   总被引:2,自引:0,他引:2  
从文明交往角度看 ,巴以冲突的持久难息缘于以下因素 :地理上 ,巴勒斯坦是巴勒斯坦人和犹太人共同的根 ;宗教上 ,伊斯兰教与犹太教尖锐对立 ;巴以交往中迥异的民族利益。巴以冲突短时期内难以平息 ,但从长远来看 ,和平共存是巴以民族问题的最终解决之路  相似文献   
22.
The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SEΔ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SEΔ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SEΔ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
23.
黑龙江汉族民歌的衍变历经了数百年的岁月沧桑,它与民族迁徙、人口变迁以及文化传统等存在着极为密切的联系。通过对黑龙江民歌与河北、山东、河南、山西民歌进行比较,表明黑龙江民歌与河北民歌之间存在着较近的亲缘关系。因此,文章试图在对较有代表性的几首黑龙江与河北民歌比较研究的基础上进一步探究黑龙江民歌衍变的影响因素。  相似文献   
24.
Conservation biology aims at assessing the status of a population, based on information which is often incomplete. Integrated population modelling based on state‐space models appears to be a powerful and relevant way of combining into a single likelihood several types of information such as capture‐recapture data and population surveys. In this paper, the authors describe the principles of integrated population modelling and they evaluate its performance for conservation biology based on a case study, that of the black‐footed albatross, a northern Pacific albatross species suspected to be impacted by longline fishing  相似文献   
25.
论非理性因素在认识中的作用   总被引:1,自引:0,他引:1  
非理性因素作为主体认识结构中的一个恒常性要素,对主体的认识活动具有非常重要的作用。情感、意志、需求等非理性因素对认识活动起着选择、调节控制和驱动的作用,直觉、灵感等非理性因素对认识的发展起突破和创造的作用。把握非理性因素在认识中的作用,有助于我们深入理解认识过程的内在机制。  相似文献   
26.
流动人口婚姻满意度实证分析   总被引:1,自引:0,他引:1  
利用"流动人口的婚姻家庭调查研究"课题收集的数据,从流动人口对婚姻生活的满意度和对配偶的满意度来描述流动人口的婚姻满意度状况,并对流动人口各方面的婚姻满意度随结婚年数的发展变化趋势进行分析。通过建立多视角多因素的综合解释模型,对流动人口婚姻满意度的影响因素进行回归分析,结果表明,夫妻关系维系因素、冲突解决方式、婚恋意愿、权利模式等是流动人口婚姻满意度的主要影响因素。  相似文献   
27.
左思风力之成因初探   总被引:1,自引:0,他引:1       下载免费PDF全文
西晋诗人左思的诗风在西晋文坛上独树一帜,称之为“左思风力”,前人对此有较多地论述,然而就诗风形成的原因却缺乏深入地探究。本文试图从社会时代背景、家庭因素、性格特征三个方面对此加以分析,旨在能够更好地把握左思其人及其诗风。  相似文献   
28.
Latina female (n= 97) and Latino male (n= 69) college students (M age = 21.4 years) completed self‐report surveys regarding family of origin experiences, including sexual communication with parents while growing up. Latino parents of this comparatively highly educated sample tended to use direct rather than indirect strategies for communicating about sexuality with their children. Young women reported higher levels of sexual communication with mothers while growing up than did young men, and respondents reported less communication with fathers than mothers. Among young women, sexual communication with mother was positively associated with non‐Mexican origin and negatively associated with having older brothers living at home. In contrast, maternal education was positively associated with mother‐son communication about sex. Paternal education and the absence of older brothers positively predicted communication with both sons and daughters. The analyses provide novel information regarding sexual communication in Latino families and suggest directions for future research.  相似文献   
29.
Missing data, and the bias they can cause, are an almost ever‐present concern in clinical trials. The last observation carried forward (LOCF) approach has been frequently utilized to handle missing data in clinical trials, and is often specified in conjunction with analysis of variance (LOCF ANOVA) for the primary analysis. Considerable advances in statistical methodology, and in our ability to implement these methods, have been made in recent years. Likelihood‐based, mixed‐effects model approaches implemented under the missing at random (MAR) framework are now easy to implement, and are commonly used to analyse clinical trial data. Furthermore, such approaches are more robust to the biases from missing data, and provide better control of Type I and Type II errors than LOCF ANOVA. Empirical research and analytic proof have demonstrated that the behaviour of LOCF is uncertain, and in many situations it has not been conservative. Using LOCF as a composite measure of safety, tolerability and efficacy can lead to erroneous conclusions regarding the effectiveness of a drug. This approach also violates the fundamental basis of statistics as it involves testing an outcome that is not a physical parameter of the population, but rather a quantity that can be influenced by investigator behaviour, trial design, etc. Practice should shift away from using LOCF ANOVA as the primary analysis and focus on likelihood‐based, mixed‐effects model approaches developed under the MAR framework, with missing not at random methods used to assess robustness of the primary analysis. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
30.
国外大学办学特色形成的因素分析及启示   总被引:2,自引:0,他引:2  
办学特色是高等院校在这个激烈竞争的时代求得生存和发展的重要因素。国外著名大学办学特色的形成受各种因素影响。其中办学理念是核心基础,学科和专业设置是集中体现,教师和毕业生的高质量是关键支撑,而大学校长则发挥着主导作用。我国的高等院校要形成自身的办学特色,应立足于这些因素,同时结合本国国情和高校自身的实际情况,借鉴和创造并举,即以前瞻性的办学理念为指导,以建立特色学科与特色专业为方向,深化管理体制改革,扩大办学自主权,大力加强教师队伍建设。  相似文献   
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