首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2939篇
  免费   360篇
  国内免费   373篇
  3672篇
  2024年   18篇
  2023年   90篇
  2022年   63篇
  2021年   74篇
  2020年   170篇
  2019年   189篇
  2018年   190篇
  2017年   186篇
  2016年   196篇
  2015年   129篇
  2014年   125篇
  2013年   497篇
  2012年   103篇
  2011年   102篇
  2010年   71篇
  2009年   112篇
  2008年   91篇
  2007年   133篇
  2006年   162篇
  2005年   132篇
  2004年   116篇
  2003年   86篇
  2002年   72篇
  2001年   83篇
  2000年   62篇
  1999年   51篇
  1998年   43篇
  1997年   39篇
  1996年   36篇
  1995年   25篇
  1994年   28篇
  1993年   20篇
  1992年   27篇
  1991年   7篇
  1990年   17篇
  1989年   11篇
  1988年   8篇
  1987年   13篇
  1986年   8篇
  1985年   9篇
  1984年   8篇
  1983年   7篇
  1982年   10篇
  1981年   5篇
  1980年   9篇
  1979年   11篇
  1978年   11篇
  1977年   7篇
  1976年   10篇
排序方式: 共有3672条查询结果,搜索用时 15 毫秒
191.
Pseudo-guessing parameters are present in item response theory applications for many educational assessments. When sample size is not sufficiently large, the guessing parameters may be ignored from the analysis. This study examines the impact of ignoring pseudo-guessing parameters on measurement invariance analysis, specifically, on item difficulty, item discrimination, and mean and variance of ability distribution. Results show that when non-zero guessing parameters are ignored from the measurement invariance analysis, item discrimination estimates tend to decrease particularly for more difficult items, and item difficulty estimates decrease unless the items are highly discriminating and difficult. As the guessing parameter increases, the size of the decrease in item discrimination and difficulty tends to increase, and the estimated mean and variance of ability distribution tend to be inaccurate. When two groups have heterogeneous ability distributions, ignoring the guessing parameter affects the reference group and the focal group differently. Implications of result findings are discussed.  相似文献   
192.
青少年特发性脊柱侧凸患者是个特殊的患病群体,患者的心理健康状况和躯体受到显著影响,青少年患者对其自身形象更为关注,心理焦虑和障碍表现更为明显。脊柱外科医生需要明确脊柱侧凸程度对患者生存质量及心理的影响,能明确其风险因素,针对不同畸形程度的患者采取个体化诊疗方案,以期最终能改善患者的疗效。  相似文献   
193.
心理账户深刻地体现了心理学和经济学的结合,是在行为经济学的大背景下开始研究的。心理账户是人们在心理上对结果,尤其是经济结果的编码,分类和估价的过程,它反映了人们在进行资金财富决策过程中的心理认知过程。心理账户与经济账户的运算法则不同,它具有非替代性。心理账户与金融投资结合形成了行为资产组合理论,心理账户与消费经济结合,形成了行为生命周期理论。  相似文献   
194.
采用荧光PCR法对199例晚期非小细胞肺癌(NSCLC )组织进行表皮生长因子受体(EGFR )基因突变检测,分析EGFR基因突变的分布特征及其与临床病理特征的相关性。结果显示56例(28.1%)存在EGFR基因突变,其中27例(13.6%)为外显子19突变,25例(12.6%)为外显子21突变,2例为外显子18突变,1例外显子20突变,1例外显子18和20的共突变。另外,除广东及安徽省铜陵市外,辽宁地区NSCLC患者EGFR基因突变率及主要突变类型与其他地区相符,常见于外显子19、21突变,其中腺癌、不吸烟患者突变率更高,更适宜EGFR-TKI靶向治疗。  相似文献   
195.
Attachment theory, developed by child psychiatrist John Bowlby, is considered a major theory in developmental psychology. Attachment theory can be seen as resulting from Bowlby's personal experiences, his psychoanalytic education, his subsequent study of ethology, and societal developments during the 1930s and 1940s. One of those developments was the outbreak of World War II and its effects on children's psychological wellbeing. In 1950, Bowlby was appointed WHO consultant to study the needs of children who were orphaned or separated from their families for other reasons and needed care in foster homes or institutions. The resulting report is generally considered a landmark publication in psychology, although it subsequently met with methodological criticism. In this paper, by reconstructing Bowlby's visit to several European countries, on the basis of notebooks and letters, the authors shed light on the background of this report and the way Bowlby used or neglected the findings he gathered.  相似文献   
196.
197.
Although a statistical model might fit well to a large proportion of the individuals of a random sample, some individuals might give ‘unusual’ responses that are not well explained by the hypothesized model. If individual responses are given as continuous response vectors, M-distances can be used to produce real valued indicators of how well an individual's response vector corresponds to a covariance structure implied by a psychometric model. In this note, we focus on the so-called one-factor model. Two M-distances, dsi and dri, which are sensitive to different aspects of the assumed factor model, have been proposed. While one of the M-distances, dri, has been derived based on Bartlett factor scores, in this note we show that the second M-distance, dsi, can be derived in an analogous fashion based on Thomson factor scores.  相似文献   
198.
199.
We present a single-subject prospective outcome study of a man with severe morphing fear and long history of OCD who was not helped by previous interventions, and who received an adapted form of cognitive behavior therapy (CBT) as part of this study. Treatment consisted of a cognitively focused approach tailored to address his fear of morphing and included developing a stronger sense of self-stability. We describe the details of the case, the treatment protocol, and the therapeutic outcomes as assessed over 36 weeks by questionnaires, rating scales, and semistructured interviews. The intervention was effective in eradicating the patient’s morphing fears and reducing other symptoms of OCD, anxiety, and depression. The presented case illustrates the need to appropriately conceptualize, assess, and address the specific nature of morphing fear symptoms in treatment.  相似文献   
200.
Life satisfaction is linked to premature morbidity and mortality and it may be compromised for individuals living in economically-disadvantaged, urban neighborhoods. The present study explores how behavioral and social-environmental health factors are associated with life satisfaction among a sample of African American young adults. Participants (N = 307, Mage = 26.6 years, 53% male) were recruited from a publicly-funded clinic for a randomized controlled trial (RCT). Data from the baseline assessment of the RCT, which included measures of sleep, depression, anxiety, social support, alcohol and drug use problems, city stress, and life satisfaction, were used for the current study. Correlation analyses assessed bivariate associations between life satisfaction and the demographic and health-related factors. Linear regression using backward elimination determined the best fitting model of factors associated with life satisfaction. Backward elimination resulted in the following variables remaining as significantly associated with life satisfaction: age (b = ?2.40, p = .017), anxiety (b = ?5.32, p < .001), and social support (b = 2.89, p = .004). Feeling rested upon waking also remained in the best fitting model, although this association did not achieve statistical significance (p = .099). The results suggest that African American adults who are younger, less anxious, and report adequate social support are more likely to report satisfaction with life. These findings add to the literature aimed at examining health and social factors impacting the well-being of African Americans living in low-income, urban communities.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号