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   186篇
  免费   12篇
  2023年   2篇
  2022年   2篇
  2021年   2篇
  2020年   2篇
  2019年   2篇
  2018年   11篇
  2017年   3篇
  2016年   12篇
  2015年   5篇
  2014年   8篇
  2013年   21篇
  2012年   14篇
  2011年   13篇
  2010年   8篇
  2009年   5篇
  2008年   7篇
  2007年   7篇
  2006年   10篇
  2005年   6篇
  2004年   5篇
  2003年   4篇
  2002年   3篇
  2001年   3篇
  2000年   5篇
  1999年   4篇
  1998年   1篇
  1994年   1篇
  1993年   3篇
  1992年   4篇
  1990年   2篇
  1989年   2篇
  1987年   2篇
  1985年   2篇
  1983年   3篇
  1982年   1篇
  1981年   1篇
  1979年   2篇
  1978年   3篇
  1977年   3篇
  1975年   1篇
  1970年   1篇
  1968年   1篇
  1966年   1篇
排序方式: 共有198条查询结果,搜索用时 15 毫秒
161.
We examined cessation among 630 smokers who quit abruptly on their own. Continuous, complete abstinence rates were 33% at 2 days, 24% at 7 days, 22% at 14 days, 19% at 1 month, 11% at 3 months, 8% at 6 months postcessation, and 3% at 6 months with biochemical verification. Slipping (smoking an average of less than 1 cigarette/day) was common (9% to 15% of subjects) and was a strong predictor of relapse; however, 23% of long-term abstainers slipped at some point. These results challenge beliefs that most smokers can initially stop smoking and that most relapse occurs later on postcessation.  相似文献   
162.
163.
164.
The goal of this research was to expand theoretical models of adolescent depression to determine whether individual differences in cognitive processing—specifically attentional control deficits—help to explain increased risk for depression during adolescence. We also examined whether this pathway was stronger in girls than in boys. A longitudinal design was used to examine whether poor attentional control in everyday life (i.e., difficulties shifting between ideas, tasks, and activities) contributes to depression over time by fostering higher levels of stress reactivity. Youth (298 boys, 338 girls) completed questionnaires assessing stress reactivity (6th and 7th grades) and depressive symptoms (6th, 7th and, 8th grades); teachers completed the shifting subscale of the Behavior Rating Scale of Executive Function (Gioia et al. 2000a) to assess attentional control (6th and 7th grades). Structural equation modeling analyses provided support for the predicted pathway in girls but not boys, yielding a significant indirect effect from 6th grade shifting deficits to 8th grade depressive symptoms via 7th grade stress reactivity. These results suggest that attentional control deficits in early adolescence heighten girls’ sensitivity to stress and consequent depressive symptoms, providing a critical direction for efforts to decrease adolescent girls’ risk for depression.  相似文献   
165.
Adolescents with conduct disorder (CD) and elevated callous-unemotional (CU) traits have been reported to present with a more severe and persistent pattern of antisocial behaviour than those with low levels of CU traits. However, relatively few studies have investigated whether there are differences in brain structure between these subgroups.We acquired diffusion tensor imaging data and used tract-based spatial statistics (TBSS) to compare adolescents with CD and high levels of CU traits (CD/CU+; n?=?18, CD and low levels of CU traits (CD/CU-; n?=?17) and healthy controls (HC; n?=?32) on measures of fractional anisotropy (FA), axial (AD), radial (RD) and mean (MD) diffusivity. Compared to CD/CU- adolescents, those with CD/CU+ presented increased FA and reduced RD and MD (lower diffusivity) in several tracts including: body and splenium of the corpus callosum, right inferior longitudinal fasciculus, ILF; right inferior fronto-occipital fasciculus, IFOF; left superior longitudinal fasciculus, SLF; left cerebral peduncle, bilateral internal capsule, left superior and posterior corona radiata, bilateral thalamic radiation and left external capsule. In addition, relative to CD/CU- individuals, adolescents with CD/CU+ showed lower diffusivity (indexed by reduced RD and MD) in left uncinate fasciculus and bilateral fornix. Finally, relative to healthy controls, CD/CU+ individuals showed lower diffusivity (reduced RD) in the genu and body of the corpus callosum and left anterior corona radiata. These results suggest that CD/CU+ individuals present with white-matter microstructural abnormalities compared to both CD/CU- individuals and age-matched healthy controls. This finding is consistent with emerging evidence suggesting that CD/CU+ represents a distinct subtype of CD, and illustrates the importance of accounting for heterogeneity within CD populations.  相似文献   
166.
167.
Little is known about the social cognitive development of young adults. Furthermore, existing studies of young adults tend to rely on college-age participants. A study of social cognition during interpersonal conflict was conducted with 100 young adult women (mean age = 25 years). The relationship of contextual variables to conflict-resolution strategy was examined. Strategy coding was done according to Selman's (1980) four-level model of interpersonal negotiation strategies. Of the features of context studied, the nature of the relationship between the participant and the other person (work-based, personal, or impersonal) was related to strategy use. Most strategies used (46%) were low-level unilateral strategies, e.g., giving in to the demands of the other person. Most participants reported conflicts at work. These data, taken with other research on young adults' perceived lack of ability at handling conflicts at work, suggest that constructive conflict management programs may be important for young adult women in the school-to-work transition.  相似文献   
168.
Rats were trained to use stimuli arising from 0 and 24 hr without food as discriminative signals for shock. In Experiment 1, one group was shocked under 0-hr food deprivation and not shocked under 24-hr food deprivation. Another group received the reverse contingency. The groups received only 3 training trials under each deprivation level. Learning was revealed in a test phase when greater extinction of freezing was observed under the nonshocked than under the shocked deprivation level for both groups. A similar pattern of results was obtained in Experiment 2 when auditory cues were also relevant throughout training. Furthermore, prior training with food deprivation cues seemed to reduce learning about auditory cues subsequently trained in compound with deprivation stimuli. The results indicate that food deprivation intensity cues can be potent discriminative stimuli. The idea that deprivation cues function as conditioned modulatory stimuli cues is also discussed.  相似文献   
169.
170.
The perception of affordances for the actions of other people (actors) was examined. Observers judged the maximum and preferred sitting heights of tall and short actors. Judgments were scaled in centimeters, as a proportion of the observer's leg length, and as a proportion of each actor's leg length. In Experiment 1 observers viewed live actors standing next to a chair. When judgments were scaled by actor leg length, they reflected the actual ordinal relation between the capabilities of the actors. The perception of affordances from kinematic displays was then evaluated. Observers differentiated tall and short actors, but only when the displays contained direct information about relations between the actors and the chair. It is concluded that observers can perceive affordances for the actions of actors and that kinematic displays can be enough to support such percepts if they preserve actor-environment relations that define affordances.  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