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811.
The planarian flatworm is one of the simplest animals to develop two eyecups that enable them to detect the presence and direction of light, which they typically avoid. In this study we assessed responses of planaria to different intensities of light. We found that they exhibited a graded, sigmoidal, photonegative response to light intensity. A two-octave increase in luminance (on the upward slope of the sigmoid) corresponded to a 9% increase in the speed planaria travelled to avoid light.  相似文献   
812.
Female athletes in the United States face the paradoxical challenge of acquiring a degree of muscularity to be successful in their sport, yet they also endure pressure from societal expectations of femininity that often don??t conform with the notion of muscularity. To address research questions about how female student-athletes balance muscularity and femininity, we conducted a mixed-methods study to examine muscularity beliefs among female student-athletes, female college students, and male college student-athletes. We quantitatively examined Drive for Muscularity Scale (DMS) scores from 221 participants attending college in the Midwestern US. Results indicated that female student-athletes reported significantly higher DMS scores than female students, but male student-athletes reported the highest DMS scores in the sample. Qualitative results indicated that female student-athletes wanted to be muscular for these reasons: functionality (45%), health (42%), external gratification (21%), and internal gratification (18%). Only 16% of female student-athletes did not want to be muscular, whereas every male student-athlete reported a desire to be muscular. The results of this study can be used to better understand the unique drive for muscularity among athletes, particularly female college student-athletes who live the paradox of negotiating societal standards of femininity with this desire to be muscular. This enhanced understanding can help create more nuanced interventions for coaches, administrators, and mental health professionals to use to help female student-athletes create space to resist constraining societal gender ideologies. Doing so can help these student-athletes actualize their athletic potential on the field as well as their interpersonal and intrapersonal potential off the field.  相似文献   
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815.
People commonly believe that they communicate better with close friends than with strangers. We propose, however, that closeness can lead people to overestimate how well they communicate, a phenomenon we term the closeness-communication bias. In one experiment, participants who followed direction of a friend were more likely to make egocentric errors—look at and reach for an object only they could see—than were those who followed direction of a stranger. In two additional experiments, participants who attempted to convey particular meanings with ambiguous phrases overestimated their success more when communicating with a friend or spouse than with strangers. We argue that people engage in active monitoring of strangers’ divergent perspectives because they know they must, but that they “let down their guard” and rely more on their own perspective when they communicate with a friend.  相似文献   
816.
Childhood anxiety is impairing and associated with later emotional disorders. Studying risk factors for child anxiety may allow earlier identification of at-risk children for prevention efforts. This study applied an ecological risk model to address how early childhood anxiety symptoms, child temperament, maternal anxiety and depression symptoms, violence exposure, and sociodemographic risk factors predict school-aged anxiety symptoms. This longitudinal, prospective study was conducted in a representative birth cohort (n = 1109). Structural equation modeling was used to examine hypothesized associations between risk factors measured in toddlerhood/preschool (age = 3.0 years) and anxiety symptoms measured in kindergarten (age = 6.0 years) and second grade (age = 8.0 years). Early child risk factors (anxiety symptoms and temperament) emerged as the most robust predictor for both parent-and child-reported anxiety outcomes and mediated the effects of maternal and family risk factors. Implications for early intervention and prevention studies are discussed.  相似文献   
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818.
Emotion appears to have a substantial impact on a wide variety of attentional functions. However, stimuli that elicit affective responses also tend to be meaningful. Here we attempted to disentangle the effects of meaning from the effects of affect on attentional capture by irrelevant distractors. Experiment 1 used a previously unfamiliar distractor stimulus, and manipulated the amount of knowledge provided to observers about the distractor. The results suggested that increases in meaning can reduce attentional capture. Experiments 2 and 3 used both familiar and unfamiliar symbols (baseball logos and flags, respectively) as distractors. Critically, of the two familiar symbols, one was rated as affective-positive and the other was rated as affective-negative. As in Experiment 1, the results showed that unfamiliar distractors can capture attention. In addition, the results also suggested that the two affective distractors captured attention (so long as they were sufficiently intense). This finding suggests that while increased knowledge can reduce capture, affect can restore an item's ability to capture attention. Finally, the results of Experiment 4 showed that observers were slower to disengage from a negative item than from a positive item. This evidence emphasizes the differential roles of semantic knowledge versus affect on attentional capture.  相似文献   
819.
Classic cognitive theory conceptualizes executive functions as involving multiple specific domains, including initiation, inhibition, working memory, flexibility, planning, and vigilance. Lesion and neuroimaging experiments over the past two decades have suggested that both common and unique processes contribute to executive functions during higher cognition. It has been suggested that a superordinate fronto–cingulo–parietal network supporting cognitive control may also underlie a range of distinct executive functions. To test this hypothesis in the largest sample to date, we used quantitative meta-analytic methods to analyze 193 functional neuroimaging studies of 2,832 healthy individuals, ages 18–60, in which performance on executive function measures was contrasted with an active control condition. A common pattern of activation was observed in the prefrontal, dorsal anterior cingulate, and parietal cortices across executive function domains, supporting the idea that executive functions are supported by a superordinate cognitive control network. However, domain-specific analyses showed some variation in the recruitment of anterior prefrontal cortex, anterior and midcingulate regions, and unique subcortical regions such as the basal ganglia and cerebellum. These results are consistent with the existence of a superordinate cognitive control network in the brain, involving dorsolateral prefrontal, anterior cingulate, and parietal cortices, that supports a broad range of executive functions.  相似文献   
820.
There has been growing interest in using adaptive training interventions such as Cogmed-RM to increase the capacity of working memory (WM), but this intervention may not be optimally designed. For instance, Cogmed-RM can target the primary memory (PM) component of WM capacity, but not the secondary memory (SM) component. The present study hypothesized that Cogmed-RM does not target SM capacity because the simple span exercises it uses may not cause a sufficient amount of information to be lost from PM during training. To investigate, we randomly assigned participants to either a standard (simple span; N = 31) or a modified (complex span; N = 30) training condition. The main findings showed that SM capacity did not improve, even in the modified training condition. Hence, the potency of span-based WM interventions cannot be increased simply by converting simple span exercises into complex span exercises.  相似文献   
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