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   1921篇
  免费   54篇
  2023年   12篇
  2022年   13篇
  2021年   13篇
  2020年   31篇
  2019年   34篇
  2018年   41篇
  2017年   50篇
  2016年   36篇
  2015年   25篇
  2014年   42篇
  2013年   202篇
  2012年   62篇
  2011年   82篇
  2010年   65篇
  2009年   56篇
  2008年   75篇
  2007年   71篇
  2006年   71篇
  2005年   61篇
  2004年   72篇
  2003年   70篇
  2002年   75篇
  2001年   30篇
  2000年   33篇
  1999年   30篇
  1998年   30篇
  1997年   27篇
  1996年   29篇
  1995年   44篇
  1994年   30篇
  1993年   33篇
  1992年   22篇
  1991年   31篇
  1990年   18篇
  1989年   25篇
  1988年   18篇
  1987年   16篇
  1986年   21篇
  1985年   27篇
  1984年   27篇
  1983年   31篇
  1982年   22篇
  1981年   34篇
  1980年   14篇
  1979年   24篇
  1978年   21篇
  1977年   19篇
  1976年   17篇
  1975年   16篇
  1973年   8篇
排序方式: 共有1975条查询结果,搜索用时 15 毫秒
251.
Space advocates, presidents, and NASA administrators have talked for decades about sending people back to the Moon and on to Mars, to stay. Neither funding nor public support has materialized. Billionaire Elon Musk has declared his intent to establish a human colony on Mars, drawing much media attention. Here Linda Billings argues that it would be unethical to contaminate a potentially habitable planet for further scientific exploration and immoral to transport a tiny, non-representative, subset of humanity—made up of people who could afford to spend hundreds of thousands to millions of dollars on the trip—to live on Mars.  相似文献   
252.
The authors examined the dimensionality and psychometric properties of the Multigroup Ethnic Identity Measure (MEIM) among Black South African adolescents (ages = 13–14; 52% female) representing several ethnic groups (Ndebele, Pedi, Sotho, Swati, Tsonga, Tswana, Venda, Xhosa, Zulu) and evaluated the measure for differential item functioning primarily among four ethnic groups (Sotho, Tswana, Xhosa, and Zulu). Results indicated that a two-dimensional model best represented the data, reflecting ethnic search/clarity and ethnic affirmations. Subsequently, we evaluated the equivalence of the MEIM among the four South African ethnic groups and a sample of African American adolescents (Mage = 15.57 years; SD = 1.22; 51% female). Further analyses revealed that configural and metric models were excellent across the four South African ethnic groups and the African American group. However, scalar invariance (i.e., intercept) was not found; the item intercepts were different for the South African ethnic groups and African Americans. Findings are discussed with consideration for conducting research on ethnic identity among youth in South Africa.  相似文献   
253.
Faces are adaptively coded relative to visual norms that are updated by experience, and this adaptive coding is linked to face recognition ability. Here we investigated whether adaptive coding of faces is disrupted in individuals (adolescents and adults) who experience face recognition difficulties following visual deprivation from congenital cataracts in infancy. We measured adaptive coding using face identity aftereffects, where smaller aftereffects indicate less adaptive updating of face‐coding mechanisms by experience. We also examined whether the aftereffects increase with adaptor identity strength, consistent with norm‐based coding of identity, as in typical populations, or whether they show a different pattern indicating some more fundamental disruption of face‐coding mechanisms. Cataract‐reversal patients showed significantly smaller face identity aftereffects than did controls (Experiments 1 and 2). However, their aftereffects increased significantly with adaptor strength, consistent with norm‐based coding (Experiment 2). Thus we found reduced adaptability but no fundamental disruption of norm‐based face‐coding mechanisms in cataract‐reversal patients. Our results suggest that early visual experience is important for the normal development of adaptive face‐coding mechanisms.  相似文献   
254.
Background and Objectives: Social stress and associated coping responses can profoundly influence women’s stress physiology and health. Implicit social attentional biases can also influence psychological and physiological stress responses. The purpose of this study was to explore whether a coping style characterized by greater use of social support predicts indices of cortisol activity in laboratory and daily life contexts among female university students. We hypothesized that the relation of this coping style to cortisol activity would be moderated by women’s attentional biases.

Methods: Seventy-four women (Mage?=?19.44, range: 17.8–27.8, 64% White) completed an interpersonal stress task and an attentional bias task in the lab, along with a self-report coping inventory. Participants provided five saliva samples during the lab protocol, followed by three saliva samples per day for three consecutive weekdays. Outcome measures included cortisol response to lab tasks (AUCg), diurnal cortisol slope, diurnal AUCg, and cortisol awakening response (CARi).

Results: A coping style characterized by greater use of social support predicted lower lab AUCg and lower, flatter average diurnal cortisol slope for women with attentional avoidance compared to women with attentional vigilance (ps?<?.05).

Conclusions: Responding to stress by using social support is linked to lower cortisol responses to social stress and diurnal cortisol activity for women with implicit avoidance of social threat cues.  相似文献   
255.
Using existing longitudinal data from 570 infants in the Maternal Lifestyle Study, we explored the predictive value of maternal and infant affect and maternal vocalizations during 2 minutes of face‐to‐face interactions at 4 months on IQ scores at 4.5 and 7 years. After controlling for demographic factors, maternal depression, and prenatal drug exposure, maternal positive affect and maternal positive vocalizations emerged as predictors of both verbal and performance IQ at 4.5 and 7 years. Although infant positive affect during the interaction with the mother was not predictive of these outcome measures, infant positive affect towards an examiner predicted verbal but not performance IQ at 4.5 years. These results suggest that maternal positive affect may index emotional engagement in interaction that facilitates both verbal and nonverbal cognitive development, while infant social positive affect is specifically related to the acquisition of verbal reasoning abilities. These findings are significant because they are based on a discrete snapshot of observable behavior in infancy (just 2 minutes of interaction), because they extend the range of maternal behaviors and characteristics known to support positive developmental outcomes, and because they are derived from high‐risk infants where prevention efforts may be beneficial. Potential mechanisms for these associations are discussed, as are the clinical implications for identifying dyads most in need of targeted interventions.  相似文献   
256.
Advances in theory and research on self‐regulation and decision‐making processes have yielded important insights into how cognitive, emotional, and social processes shape risk perceptions and risk‐related decisions. We examine how self‐regulation theory can be applied to inform our understanding of decision‐making processes within the context of genomic testing, a clinical arena in which individuals face complex risk information and potentially life‐altering decisions. After presenting key principles of self‐regulation, we present a genomic testing case example to illustrate how principles related to risk representations, approach and avoidance motivations, emotion regulation, defensive responses, temporal construals, and capacities such as numeric abilities can shape decisions and psychological responses during the genomic testing process. We conclude with implications for using self‐regulation theory to advance science within genomic testing and opportunities for how this research can inform further developments in self‐regulation theory.  相似文献   
257.
The current exploratory study utilized a family strengths framework to identify marital expectations in 39 strong African American heterosexual marriages. Couples reflected on their marital expectations over their 10 or more years of marriage. Three themes emerged through qualitative analysis and the participants' own words were used in the presentation of the themes. African Americans indicated that there was growth in marital expectations over time, with marital expectations often beginning with unrealistic expectations that grew into more realistic expectations as their marriages progressed. Participants also indicated that core expectations in strong African American marriages included open communication, congruent values, and positive treatment of spouse. Finally, participants explained there is an “I” in marriage as they discussed the importance of autonomy within their marital relationships. Results are discussed in association with existing research and theory.  相似文献   
258.
259.
For monolingual English-speaking children, judgment and production of stress in derived words, including words with phonologically neutral (e.g., -ness) and non-neutral suffixes (e.g., -ity), is important to both academic vocabulary growth and to word reading. For Mandarin-speaking adult English learners (AELs) the challenge of learning the English stress system might be complicated by cross-linguistic differences in prosodic function and features. As Mandarin-speakers become more proficient in English, patterns similar to those seen in monolingual children could emerge in which awareness and use of stress and suffix cues benefit word reading. A correlational design was used to examine the contributions of English stress in derivation with neutral and non-neutral suffixes to English word and nonword reading. Stress judgment in non-neutral derivation predicted word reading after controlling for working memory and English vocabulary; whereas stress production in neutral derivation contributed to word reading and pseudoword decoding, independent of working memory and English vocabulary. Although AELs could use stress and suffix cues for word reading, AELs were different from native English speakers in awareness of non-neutral suffix cues conditioning lexical stress placement. AELs may need to rely on lexical storage of primary stress in derivations with non-neutral suffixes.  相似文献   
260.
The UPPS‐P model of impulsivity is gaining popularity among personality and substance use researchers, but questions remain as to whether its five facets have incremental validity in explaining substance use over a more parsimonious model specifying only two facets: reward drive and rash impulsiveness. In three cross‐sectional studies (total N = 486), we investigated whether the novel components of the UPPS‐P model (negative Urgency, Premeditation, Perseverance, Sensation seeking, Positive urgency) predicted typical and problematic alcohol and cannabis use after accounting for reward drive, rash impulsiveness and trait neuroticism (assessed with the Eysenck Personality Questionnaire). Reward drive and rash impulsiveness scores were calculated using principal components analysis of multiple scales, including UPPS‐P premeditation and sensation seeking. Results showed that rash impulsiveness was a robust predictor of typical and problematic substance use. The novel facets of the UPPS‐P did not improve prediction of typical substance use. The urgency scales inconsistently predicted problematic use. Specifically, negative urgency predicted one of three measures of negative consequences from alcohol use, and positive urgency only predicted negative consequences from cannabis use. Results suggest that the three novel facets of the UPPS‐P model add little over a two component model in explaining substance use, although may provide preliminary evidence for the utility of a revised global urgency construct in explaining problematic substance use. Copyright © 2017 European Association of Personality Psychology  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