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   944篇
  免费   14篇
  国内免费   21篇
  979篇
  2023年   6篇
  2022年   6篇
  2021年   6篇
  2020年   11篇
  2019年   14篇
  2018年   11篇
  2017年   12篇
  2016年   9篇
  2015年   7篇
  2014年   7篇
  2013年   50篇
  2012年   5篇
  2011年   10篇
  2010年   8篇
  2009年   17篇
  2008年   11篇
  2007年   14篇
  2006年   9篇
  2005年   7篇
  2004年   3篇
  2003年   7篇
  2002年   9篇
  2001年   5篇
  2000年   6篇
  1999年   5篇
  1998年   4篇
  1997年   3篇
  1996年   1篇
  1995年   3篇
  1994年   3篇
  1993年   2篇
  1992年   1篇
  1991年   2篇
  1990年   4篇
  1989年   2篇
  1987年   3篇
  1986年   1篇
  1985年   48篇
  1984年   61篇
  1983年   45篇
  1982年   69篇
  1981年   64篇
  1980年   79篇
  1979年   74篇
  1978年   56篇
  1977年   40篇
  1976年   46篇
  1975年   39篇
  1974年   40篇
  1973年   34篇
排序方式: 共有979条查询结果,搜索用时 0 毫秒
151.
This study used the classical A‐not‐B task (Piaget, 1954 ) to explore individual differences in cognitive flexibility in 10‐month‐old infants by: (1) examining how differences in search performance during A trials relate to search performance during B trials; (2) studying the relation between temperamental dimensions and A‐not‐B performance; and (3) investigating differences in search performance between looking and reaching responses within the same task. Forty infants were tested on a fixed‐design‐version of the A‐not‐B task, not allowing for training or individual adjustment, but instead eliciting additional search behaviors than the common correct responses in A trials and perseverative errors in B trials. Infants were also rated by their parents on the temperamental scales Activity level and Attention span. The main findings were: (1) performance on A trials affected B trial performance, with infants being more correct on A trials having more incorrect and less ‘no search’ responses on B trials; (2) activity level, but not attention span, was related to performance on the A‐not‐B task, with infants performing better on A trials having a lower activity level; and (3) there were a few differences in performance with regard to modality, indicating that responding correctly by looking may be less cognitively demanding than doing so by reaching. This study demonstrated that 10‐month‐olds show a wide variation of search behaviors on this A‐not‐B task, resulting in individual differences in performance. These differences are suggested to reflect variation in temperamental activity level as well as maturity of short term/working memory, inhibition and cognitive flexibility.  相似文献   
152.
Personality traits are associated with major adverse coronary events (MACE) in patients with coronary artery disease (CAD). However, the link between personality traits and intravascular morphology in CAD patients is poorly understood. This study investigated the relationship between personality traits, specifically Type A behavior pattern and Type D personality, and plaque vulnerability. After adjustment for demographic and clinical factors, multivariable regression analysis showed no association between Type A and optical coherence tomography indices. However, Type D personality was independently associated with lipid plaque, thin cap fibroatheroma (TCFA), and fibrous cap thickness. More specifically, negative affectivity of Type D was related to lipid plaque, TCFA and fibrous cap thickness, and social inhibition was associated with plaque rupture. Our results show that Type D personality was associated with plaque vulnerability, independent of clinical factors. Measurement of negative affectivity and social inhibition will increase our understanding of the progressive phase of the plaque vulnerability, which can contribute to the early identification of high risk patients and reduce the incidence of MACE.  相似文献   
153.
154.
In "Action and Responsibility,' Joel Feinberg pointed to an important idea to which he gave the label "the accordion effect.' Feinberg's discussion of this idea is of interest on its own, but it is also of interest because of its interaction with his critique, in his "Causing Voluntary Actions,' of a much discussed view of H. L. A. Hart and A. M. Honoré that Feinberg labels the "voluntary intervention principle.' In this essay I reflect on what the accordion effect is supposed by Feinberg to be, on differences between Feinberg's understanding of this idea and that of Donald Davidson, and on the interaction between Feinberg's discussion of the accordion effect and his critique of the voluntary intervention principle.  相似文献   
155.
The level of motivation (i.e. incentive power) is thought to be one of the most important factors affecting performance and learning in various tasks. We investigated whether reward quality has an effect on the performance of family dogs in a two-way object choice test in which they can find the hidden food by relying on distal momentary human pointing cues. In three experiments we varied (1) the type of food reward according to the subjects’ own preference; (2) the quality of the reward offered at the same time in the indicated and not-indicated locations; and (3) the order of the high or low quality rewards in consecutive sessions. In Experiment 1, we first tested whether dogs prefer one kind of reward over another. Then one group was tested with the ‘preferred’ food as reward in the indicated bowl, while dogs in the other group received the ‘non-preferred’ food as reward. We did not find any difference between the performance and choice latencies of the two groups. In Experiment 2 for the first group, the indicated bowl contained a piece of carrot and the not-indicated bowl was empty. In the second group the indicated bowl contained carrot, but the not-indicated bowl contained sausage. According to a preliminary preference test, most dogs prefer sausage over carrot invariably. After 20 trials, the two groups performed surprisingly similarly. There was no difference found between groups in the number of correct choices, incorrect choices and non-choices. However, the comparison between the first and last five trials revealed that subjects who found sausage when they chose the not-indicated bowl (did not follow the pointing) chose the non-indicated bowl significantly more often toward the end of their test session. In Experiment 3, each dog received two sessions with 12 pointing trials in each. For the first session, one group was rewarded with sausage and the other with carrot upon choosing the indicated bowl. In the second session, the indicated bowl contained dry dog food for both groups. We found that correct choices and response latencies did not change over two sessions in the ‘sausage’ group. In the ‘carrot’ group, the dogs chose faster in the second session, but their performance did not improve; in fact, they chose the not-indicated bowl more often than the indicated bowl. As a conclusion, we can say that reward quality had some effect on dogs’ choice behavior in these experiments. The drop in their performance was not drastic, taking into account the general refusal to eat one of the ‘rewards’ (carrot) during the preference tests and also during the test trials. It seems that incentive contrast may play a relatively minor role in dog-human social interactions. Appropriate reward quality can be very important in asocial problem solving tasks, but, when interacting with humans, following human signals may override the effect of changed incentive power.  相似文献   
156.
Resumen

La presente investigación tuvo como objetivo estudiar el efecto de la hostilidad autoinformada en la reactividad cardíaca de sujetos Tipo A/B. Los sujetos fueron 40 estudiantes varones repartidos en cuatro grupos: (1) Tipo A con alta Hostilidad, (2) Tipo A con baja Hostilidad, (3) Tipo B con alta Hostilidad y (4) Tipo B con baja Hostilidad. Todos ellos pasaron por tres pruebas de reactividad psicofisiológica: El Test de la Respuesta Cardíaca de Defensa ante estimulación auditiva intensa, una Tarea de Aritmética Mental y una Tarea de Juego de Vídeo Competitivo. La variable dependiente registrada fue la tasa cardíaca. Los resultados indican que en las tres pruebas no se observan diferencias en la reactividad de la tasa cardíaca entre sujetos Tipo A y B con alta Hostilidad autoinformada. Sin embargo, sí se observan diferencias entre sujetos Tipo A y B con baja Hostilidad autoinformada, siendo los sujetos Tipo A los que muestran mayores incrementos en tasa cardíaca durante la Respuesta Cardíaca de Defensa y el Juego de Vídeo Competitivo. En la Tarea de Aritmética Mental se observa esta tendencia, aunque no llegan a ser diferencias significativa s. Estos resultados sugieren que la supresión o negación de la hostilidad en sujetos Tipo A está asociada con un incremento en la reactividad cardiovascular.  相似文献   
157.
Our preferences are sensitive to social influences. For instance, we like more the objects that are looked-at by others than non-looked-at objects. Here, we explored this liking effect, using a modified paradigm of attention cueing by gaze. First, we investigated if the liking effect induced by gaze relied on motoric representations of the target object by testing if the liking effect could be observed for non-manipulable (alphanumeric characters) as well as for manipulable items (common tools). We found a significant liking effect for the alphanumeric items. Second, we tested if another type of powerful social cue could also induce a liking effect. We used an equivalent paradigm but with pointing hands instead of gaze cues. Pointing hands elicited a robust attention-orienting effect, but they did not induce any significant liking effect. This study extends previous findings and reinforces the view of eye gaze as a special cue in human interactions.  相似文献   
158.
双酚A (bisphenol, BPA)是一种广泛存在的环境内分泌干扰物,它可与雌激素受体结合干扰内源性雌激素对中枢神经系统的调控作用。本研究通过将10周龄小鼠灌胃染毒BPA (0.4、4、40 mg/kg/day)3个月,研究长期BPA暴露对成年小鼠记忆行为和突触可塑性的影响。开场行为测试结果表明, BPA (0.4、4、40 mg/kg/day)增加雄性的站立次数和理毛频率, BPA (4 mg/kg/day)却显著减少雌鼠的站立次数。水迷宫和被动回避行为模型检测显示, BPA主要损伤雄鼠的空间学习记忆和被动回避记忆。通过制备海马CA1区超薄切片后,电镜观测发现, BPA (0.4、40 mg/kg/day)暴露降低雄鼠海马CA1区突触数密度,缩短雄鼠突触前活性带长度,减小雄鼠突触后致密体(PSD)厚度,增加雄鼠突触间隙宽度。进一步用Western blot方法检测突触前、后的标志性蛋白Synapsin I和PSD95以及兴奋性氨基酸NMDA受体NR1亚基和AMPA受体GluR1亚基蛋白的表达,发现BPA暴露致雄鼠Synapsin I、PSD95、NR1蛋白表达水平下调。而BPA对雌鼠的记忆行为、突触形态、突触蛋白和受体蛋白均没有明显作用。以上结果提示长期B PA暴露性别特异性地影响成年小鼠的活动性和探究行为,损伤雄鼠的学习记忆,这些作用可能通过下调突触蛋白和NMDA受体的表达而负性影响突触结构可塑性,最终影响雄鼠的学习记忆功能。  相似文献   
159.
Abstract

Recent investigations suggest that the hostility component of the Type A behavior patter (TABP) is a greater detriment to health than the overall pattern. Some researchers suggest that certain Type A characteristics (e.g., job-involvement) are actually adaptive. This study compared the relative relationship of the TABP and hostility to career-related achievement and psychosocial adjustment among 223 service-delivery employees. Male and female participants completed the Jenkins Activity Survey and the MMPI Hostility Scale as part of a cardiovascular disease risk factor screening. The TABP was positively associated with managerial status for both men and women. However, the TABP was positively related to psychosocial adjustment variables among men only. Hostility was significantly related to undesirable outcomes including lower job status, life dissatisfaction, and unfavorable perceptions of the workplace for both men and women. Discussion addresses organizational factors which might perpetuate hostility and the TABP, as well as gender differences in the experience of these constructs.  相似文献   
160.
Abstract

Pituitary-adrenal axis was studied in terms of Type A behaviour, hostility and vital exhaustion among 69 healthy middle-aged men. The results showed that psychological factors could explain a significant proportion of the biologically manipulated responses of HPA axis, but they worked in different ways. Type A behaviour was related to a high level of mean basal ACTH and a low level of cortisol response to ACTH stimulation after dexamethasone suppression; hostility was related to a high level of mean basal cortisol and a high cortisol in cortisol/ACTH ratio, while vital exhaustion was characterized by a low level of mean basal ACTH and a decreased ACTH in relation to cortisol. The adrenocortical patterns, i.e. a high ACTH-low cortisol; a high cortisol; and a low ACTH-low mean basal cortisol, as related to Type A behaviour, hostility and exhaustion, respectively, are in line with the traditional physiological stress model and suggest that different adrenocortical responses might be able to identify different mental stress processes. Sense of control has been suggested to be a key concept for psychological understanding of this finding.  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