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901.
Two studies investigated the impact of past ingroup experiences on individual aspirations and effort. Participants were told that in the past, members of their group had either been offered no opportunities (closed), few opportunities (token), or equal opportunities (open) to achieve a desired outcome. The results show that past group experiences determine responses to current opportunities and affect the perceived feasibility of individual success as well as individual performance. Exposure to a token system has different effects, depending on whether the group is historically advantaged or disadvantaged. Whereas those with a collective history of success see token mobility as a challenge and show superior performance, the same situation constitutes a threat to members of a historically disadvantaged group, who fail to take advantage of the opportunities offered to them and perform suboptimally.  相似文献   
902.
Hypothalamo-pituitary-adrenal (HPA) axis changes have been reported in several disease states, including major depressive disorder, rheumatoid arthritis, multiple sclerosis and various other conditions associated with chronic pain. These observations suggest that stress and the HPA axis may play important roles in the pathology of these diseases. In order to contribute to a better understanding of the role that chronic stress may play in human pathology, this review article explores the involvement of the HPA axis in those animal models of chronic pain and inflammation that entail persistent rather than intermittent stress.  相似文献   
903.
Measuring the changes in neurotransmitter extracellular levels in discrete brain areas is considered a tool for identifying the neuronal systems involved in specific behavioral responses or cognitive processes. Acetylcholine (ACh) is the first neurotransmitter whose diffusion from the central nervous system was investigated and whose extracellular levels variations were correlated to changes in neuronal activity. This was done initially by means of the cup technique and then by the microdialysis technique. The latter, notwithstanding some technical limitations, makes it possible to detect variations in extracellular levels of ACh in unrestrained, behaving animals. This review summarizes and discusses the results obtained investigating the changes in ACh release during performance of operant tasks, exposition to novel stimuli, locomotor activity, and the performance of spatial memory tasks, working memory, and place preference memory tasks. Activation of the forebrain cholinergic system has been demonstrated in many tasks and conditions in which the environment requires the animal to analyze novel stimuli that may represent a threat or offer a reward. The sustained cholinergic activation, demonstrated by high levels of extracellular ACh observed during the behavioral paradigms, indicates that many behaviors occur within or require the facilitation provided by the cholinergic system to the operation of pertinent neuronal pathways.  相似文献   
904.
It has been repeatedly found (e.g., Beck, 1982; Beck & Ambler, 1973) that a tilted T is detected better than an L when presented on the background of a number of upright Ts, although in isolation both are discriminated from an upright T about equally well. We demonstrate that an analogous interaction between context presence and stimulus type can be obtained with color stimuli: A light green was discriminated from a dark green better than an olive brown was, yet that occurred only in the context of a background of three dark green disks. This indicates that the effects, both original and novel, probably are not due to anything peculiar to form perception, such as line arrangement or supraelement configurations. It is suggested that the presence of collateral background stimuli probably enables the perceptual system to capitalize on relative judgment involving contrasts or deviations from a presented anchor value.  相似文献   
905.
We examined grouping under inattention using Driver, Davis, Russell, Turatto, & Freeman’s (2001) method. On each trial, two successive displays were briefly presented, each comprising a central target square surrounded by elements. The task was to judge whether the two targets were the same or different. The organization of the background elements stayed the same or changed, independently of the targets. In different conditions, background elements grouped into columns/rows by color similarity, a shape (a triangle/arrow, a square/cross, or a vertical/horizontal line) by color similarity, and a shape with no other elements in the background. We measured the influence of the background on the target same-different judgments. The results imply that background elements grouped into columns/rows by color similarity and into a shape when no segregation from other elements was involved and the shape was relatively “good.” In contrast, no background grouping was observed when resolving figure-ground relations for segregated units was required, as in grouping into a shape by color similarity. These results suggest that grouping is a multiplicity of processes that vary in their attentional demands. Regardless of attentional demands, the products of grouping are not available to awareness without attention.  相似文献   
906.
Following the September 2001 terrorist attacks on the United States, much support for torture interrogation of terrorists has emerged in the public forum, largely based on the “ticking bomb” scenario. Although deontological and virtue ethics provide incisive arguments against torture, they do not speak directly to scientists and government officials responsible for national security in a utilitarian framework. Drawing from criminology, organizational theory, social psychology, the historical record, and my interviews with military professionals, I assess the potential of an official U.S. program of torture interrogation from a practical perspective. The central element of program design is a sound causal model relating input to output. I explore three principal models of how torture interrogation leads to truth: the animal instinct model, the cognitive failure model, and the data processing model. These models show why torture interrogation fails overall as a counterterrorist tactic. They also expose the processes that lead from a precision torture interrogation program to breakdowns in key institutions—health care, biomedical research, police, judiciary, and military. The breakdowns evolve from institutional dynamics that are independent of the original moral rationale. The counterargument, of course, is that in a society destroyed by terrorism there will be nothing to repair. That is why the actual causal mechanism of torture interrogation in curtailing terrorism must be elucidated by utilitarians rather than presumed.  相似文献   
907.
Idiom comprehension was assessed in 10 aphasic patients with semantic deficits by means of a string-to-picture matching task. Patients were also submitted to an oral explanation of the same idioms, and to a word comprehension task. The stimuli of this last task were the words following the verb in the idioms. Idiom comprehension was severely impaired, with a bias toward the literal interpretation. Very few errors were produced with words, making impossible to establish a correlation between comprehension of idioms and of individual words. The difficulties in idiom comprehension seemed to be due to the fact that patients rely on a literal-first strategy, accessing a figurative interpretation only when the linguistic analysis fails to yield acceptable results.  相似文献   
908.
A range of behavior-much deemed problematic by society-is treated with behavioral methods or psychotropic medications. Although the processes associated with behavioral interventions have been investigated using conceptual, experimental, and applied analyses, less is known about the behavioral processes associated with the use of psychotropic medication. Psychotropic drugs produce at least two types of effects of behavioral interest: (a) primary effects of drug action on target behaviors and (b) side effects that change the target or other behavior. Although an empirical literature exists regarding the former effects, little attention has been given to the latter topic. In this paper we offer a conceptual analysis of the side effects of psychotropic medication. We propose that the side effects of various drugs can influence behavior by functioning as motivating operations, conditional or discriminative stimuli, or by establishing new response-reinforcer relations. This conceptualization may facilitate the empirical analysis of how psychotropic drugs change behavior.  相似文献   
909.
This study examined the contribution of individual and family variables to depressive symptoms among youths in a family-centered culture. Participants were 262 Mexican adolescents (mean age = 15.9 years). At the individual level, gender (being female) and higher levels of perceived stressfulness of life events and ruminative coping style were correlated with higher frequency of depressive symptoms. At the family level, higher levels of perceived parental warmth and acceptance and parental monitoring were correlated with lower levels of depressed mood, whereas higher levels of parent-adolescent conflict were associated with greater frequency of depressive symptoms. Regression analyses confirmed our prediction that both individual factors (gender, ruminative coping) and family factors (parental warmth and parental monitoring) would make unique contributions to depressive symptoms. The model comprised of individual and family variables accounted for 50% of the variance in depressed mood. Moreover, parental warmth and acceptance attenuated the impact of ruminative coping style on adolescents' depressive symptomatology. Findings are discussed in relation to previous research on adolescents in another family-centered culture (China), and directions for future research are proposed.  相似文献   
910.
The aim of this work was to obtain an abridged form of the Adolescent Coping Scale (Spanish version) that included items representative of the various factorial dimensions identified as stable. The scale (80 items) was administered to 800 Argentine adolescents. Factor analyses, principal axes and oblimin solution, were performed. An abridged scale was obtained, consisting of 46 items that were grouped into 11 dimensions: Cognitive Redefinition, Self-Blame, Fatalism, Evasion Through Amusement, Problem-Focused Coping (which includes requests for information and action), Evasion Through Physical Activity, Emotional Support, Emotional Discharge and Somatization, Anxiety, Isolation, and No Action. The reliability coefficients were found to be satisfactory.  相似文献   
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