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   3561篇
  免费   441篇
  国内免费   906篇
  4908篇
  2024年   7篇
  2023年   78篇
  2022年   88篇
  2021年   124篇
  2020年   167篇
  2019年   145篇
  2018年   164篇
  2017年   166篇
  2016年   171篇
  2015年   125篇
  2014年   136篇
  2013年   321篇
  2012年   239篇
  2011年   288篇
  2010年   272篇
  2009年   256篇
  2008年   286篇
  2007年   354篇
  2006年   310篇
  2005年   301篇
  2004年   199篇
  2003年   138篇
  2002年   94篇
  2001年   58篇
  2000年   57篇
  1999年   53篇
  1998年   39篇
  1997年   31篇
  1996年   20篇
  1995年   29篇
  1994年   27篇
  1993年   17篇
  1992年   12篇
  1991年   15篇
  1990年   11篇
  1989年   17篇
  1988年   11篇
  1987年   11篇
  1986年   5篇
  1985年   12篇
  1984年   7篇
  1983年   6篇
  1982年   7篇
  1981年   10篇
  1980年   6篇
  1979年   9篇
  1976年   3篇
  1975年   2篇
  1973年   1篇
  1972年   2篇
排序方式: 共有4908条查询结果,搜索用时 10 毫秒
181.
Many studies have suggested that emotional stimuli orient and engage attention. There is also evidence that animate stimuli, such as those from humans and animals, cause attentional bias. However, categorical and emotional factors are usually mixed, and it is unclear to what extent human context influences attentional allocation. To address this issue, we tracked participants' eye movements while they viewed pictures with animals and inanimate images (i.e., category) as focal objects. These pictures had either negative or neutral emotional valence, and either human body parts or nonhuman parts were near the focal objects (i.e., context). The picture's valence, arousal, position, size, and most of the low-level visual features were matched across categories. The results showed that nonhuman animals were more likely to be attended to and to be attended to for longer times than inanimate objects. The same pattern held for the human contexts (vs. nonhuman contexts). The effects of emotional valence, category, and context interacted. Specifically, in images with a negative valence, focal animals and objects with human context had comparable numbers of gaze fixations and gaze duration. These results highlighted the attentional bias to animate parts of a picture and clarified that the effects of category, valence, and picture context interacted to influence attentional allocation.  相似文献   
182.
Lei Q  Bao Y  Wang B  Gutyrchik E 《Cognitive processing》2012,13(Z1):S223-S227
When a target appears in the same peripheral location as a previous cue, responding is typically delayed if the cue-target interval is relatively long. This phenomenon is termed inhibition of return (IOR) and has been suggested to reflect an attentional bias in favour of novel visual space. It has been demonstrated recently that IOR is much stronger in the far periphery than in the perifoveal visual field. The present study further investigated the neural mechanisms underlying this eccentricity effect of IOR with an event-related fMRI technique. The results demonstrated a stronger activation in visual cortex for perifoveal processing and a broader activation in multiple brain areas for peripheral processing. When IOR effects were compared between these two areas, a stronger activation of the fronto-parietal network was evidenced for perifoveal versus peripheral IOR, while the prefrontal cortex was more strongly involved in the peripheral IOR versus perifoveal IOR. These results suggest that different neural mechanisms are mediating the dissociable inhibitory functions between the perifoveal and peripheral visual field.  相似文献   
183.
Li L  Fan M  Sun B  Wang R  Mo L  Zhang JX 《Psychological reports》2012,110(3):935-945
The event-related brain potential (ERP) technique was used to investigate the neural mechanism of non-target language processing in Chinese-English bilinguals. Participants were presented with a mixed list of Chinese and English words and required to make conceptual decisions for words in one language and ignore words in the other non-target language. Regardless of whether the nontarget word was in Chinese or English, the ERPs they elicited were modulated by word frequency, suggesting that their meaning had been accessed. The N400 peak was delayed in the English as the non-target language condition, probably because participants were less proficient in English. The results suggest that the non-target language can be processed during conceptual tasks with participants' proficiency in this language being a critical factor.  相似文献   
184.
Li Z  Wang L  Zhang L 《Psychological reports》2012,110(1):263-275
The present study used a sample of Chinese adolescents and validated a short-form of the Egna Minnen Betr?ffande Uppfostran: One's Memories of Upbringing (s-EMBU) assessing perceived parental rearing styles. A Chinese revision of the s-EMBU by the authors was administered to a total of 779 high school students, ages 11 to 19 years. Exploratory factor analysis with half of the sample yielded a three-factor solution of Rejection, Emotional Warmth, and Overprotection, accounting for 47.1% of the total variance onthe father form and 48.8% of the total variance on the mother form. Then, confirmatory factor analysis indicated a good fit of the three-factor model to the data in the other half of the sample. The three subscales consisted of 6, 6, and 7 items, respectively. Scores on these subscales had Cronbach alphas ranging from .71 to .81, indicating adequate internal consistency. These psychometric properties suggest its applicability for research with Chinese adolescents.  相似文献   
185.
Hu Z  Zhang R  Zhang Q  Liu Q  Li H 《Brain and language》2012,121(1):70-75
Previous studies have found a late frontal-central audiovisual interaction during the time period about 150-220 ms post-stimulus. However, it is unclear to which process is this audiovisual interaction related: to processing of acoustical features or to classification of stimuli? To investigate this question, event-related potentials were recorded during a words-categorization task with stimuli presented in the auditory-visual modality. In the experiment, congruency of the visual and auditory stimuli was manipulated. Results showed that within the window of about 180-210 ms post-stimulus more positive values were elicited by category-congruent audiovisual stimuli than category-incongruent audiovisual stimuli. This indicates that the late frontal-central audiovisual interaction is related to audiovisual integration of semantic category information.  相似文献   
186.
In reading music, the acquisition of pitch information depends mostly on the spatial position of notes, hence more spatial processing, whereas the acquisition of temporal information depends mostly on the visual features of notes and object recognition. This study used both electrophysiological and behavioral methods to compare the processing of pitch and duration in reading single musical notes. It was observed that in the early stage of note reading, identification of pitch could elicit greater N1 and N2 amplitude than identification of duration at the parietal lobe electrodes. In the later stages of note reading, identifying pitch elicited a greater negative slow wave at parietal electrodes than did identifying note duration. The sustained contribution of parietal processes for pitch suggests that the dorsal pathway is essential for pitch processing. However, the duration task did not elicit greater amplitude of any early ERP components than the pitch task at temporal electrodes. Accordingly, a double dissociation, suggesting involvement of the dorsal visual stream, was not observed in spatial pitch processing and ventral visual stream in processing of note durations.  相似文献   
187.
188.
This paper first discusses the relationship between Kullback–Leibler information (KL) and Fisher information in the context of multi-dimensional item response theory and is further interpreted for the two-dimensional case, from a geometric perspective. This explication should allow for a better understanding of the various item selection methods in multi-dimensional adaptive tests (MAT) which are based on these two information measures. The KL information index (KI) method is then discussed and two theorems are derived to quantify the relationship between KI and item parameters. Due to the fact that most of the existing item selection algorithms for MAT bear severe computational complexity, which substantially lowers the applicability of MAT, two versions of simplified KL index (SKI), built from the analytical results, are proposed to mimic the behavior of KI, while reducing the overall computational intensity.  相似文献   
189.
Twin and family studies have shown that genetic factors play a role in the development of conduct disorder (CD). The purpose of this study was to identify genetic variants associated with CD using a family-based association study. We used 4,720 single nucleotide polymorphisms (SNPs) from the Illumina Panel and 11,120 SNPs from the Affymetrix 10K GeneChips genotyped in 155 Caucasian nuclear families from Genetic Analysis Workshop (GAW) 14, a subset from the Collaborative Study on the Genetics of Alcoholism (COGA). 20 SNPs had suggestive associations with CD (p < 10−3), nine of which were located in known genes, including ADAM10 (rs383902, p = 0.00036) and CAMK2A (rs2053053, p = 0.00098). Our results were verified using the International Multi-Center ADHD Genetics Project (IMAGE) dataset. In conclusion, we identified several loci associated with CD. Especially, the two genes (ADAM10 and CAMK2A) have been reported to be associated with Alzheimer’s disease, bipolar disorder and depression. These findings may serve as a resource for replication in other populations.  相似文献   
190.
Yang H  Jin G  Ren D  Luo S  Zhou T 《Brain and cognition》2011,76(1):206-210
This study investigated the effect of isoflavone aglycone (IA) on the learning and memory performance of senescence-accelerated mice, and explored its neural protective mechanism. Results showed that SAM-P/8 senescence-accelerated mice treated with IA performed significantly better in the Y-maze cognitive test than the no treatment control (P<0.05). The cortex AchE activity, serum SOD and GSH-Px activities were notably higher (P<0.05). MDA concentration and the β-secretase activity in the hippocampal tissue were both lower (P<0.05). Additionally, the number of hippocampal neurons was increased and cell morphology was significantly improved. Data suggested that IA could indirectly increase concentration of the cholinergic neural transmitter Ach through regulation of AchE, therefore improving the central cholinergic function and enhancing the learning and memory ability. By reducing the β-secretase activity, IA could decrease the formation and deposition of insoluble Adebris, relieve the resulted toxicity and damage to neurons, and thereby effectively protect the nervous system.  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