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891.
892.
The purpose of this study was to examine whether teaching three participants with learning disabilities to name and identify critical components (i.e., opening sentence, detail sentences, and key words) for four expository text structures, and to discriminate between well-written and poorly written components would improve their expository writing performance. After instruction, one participant immediately improved her expository paragraph writing skills. However, two participants needed additional instruction and feedback on their writing before their paragraph writing improved. Social validation of the study outcomes was assessed by comparing participants' paragraphs before and after instruction to paragraphs produced by same age peers without disabilities. After instruction, participants' paragraph scores were above the mean score of the normative comparison group. Implications for teaching writing skills to students with learning disabilities, and suggestions for future research are discussed.  相似文献   
893.
Two groups of mothers and their infants (24 infants, mean age=3.5 months and 24 infants, mean age=5.5 months) were video‐ and audio‐taped in their homes while playing with a Jack‐in‐the‐box. The mean fundamental frequency of spontaneous surprise exclamations of mothers when opening the toy were analysed, and infant and maternal facial expressions of surprise were coded in three regions of the face. A t‐test established that significantly more of the older children in comparison with younger children showed surprise (t=?2.96, df=46, p<0.005, 2‐tailed). Twenty‐nine per cent of the younger infants, in comparison with 67% of the older children showed facial expressions of surprise. A t‐test of maternal pitch height (Hz) indicated that mothers exclaimed in surprise with a higher pitch when the child did not show a surprise facial expression (mean=415.61 Hz) in comparison with the child showing surprise (mean=358.97 Hz; t=2.9, df=46, p=0.006, 2‐tailed). A multiple regression established that infant's expression was a stronger predictor of maternal vocal pitch than was the age of the infant. These results are discussed in terms of maternal use of emotional expressions as ‘social signals’. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
894.
895.
In 3 experiments, the authors tested performance in simple tone matching and classification tasks. Each tone was defined on location and frequency dimensions. In the first 2 experiments, participants completed a same-different matching task on the basis of one of these dimensions while attempting to ignore irrelevant variation in the other dimension. In Experiment 3, in which the tones were classified either by frequency or location, the authors explored intertrial repetition effects. The patterns of performance across these different tasks were remarkably similar and were taken to reveal basic characteristics of stimulus encoding processes. The data suggest a processing sequence in audition that reveals an early stage in which location and frequency are treated as being integral and a latter stage in which location and frequency are separable.  相似文献   
896.
This study assessed the factor structure of the Questionnaire on Smoking Urges (QSU), a commonly used assessment of cravings for cigarettes, with a sample of smokers presenting for treatment in a smoking cessation trial. On the basis of previous research, three confirmatory factor analytic models were tested. Model 1 hypothesized a 26-item, 2-factor model using the items reported in the original QSU analysis by S. T. Tiffany and D. J. Drobes (1991). Model 2 hypothesized a 12-item, 2-factor model comprised of the 6 most robust items found in each of the 2 factors of the original factor analysis. Using the 12 items from Model 2, Model 3 hypothesized a 12-item, 1-factor model. The 2nd model was found to fit the data best. Reliability was also tested using values obtained in this 2nd model, and these estimates were found to be reasonably good. Future research directions for the QSU are discussed.  相似文献   
897.
The purpose of this study is to estimate the relationship between receiving emotional support from parents early in life and an individual's health in adulthood. Analysis of data from a nationally representative sample of adults ages 25-74 years suggests that a lack of parental support during childhood is associated with increased levels of depressive symptoms and chronic conditions in adulthood. These associations between early parental support and adult health persist with increasing age throughout adulthood. Personal control, self-esteem, and social relationships during adulthood account for a large portion of these long-term associations. These findings underscore the importance of adopting a life course perspective in studying the social determinants of health among adults.  相似文献   
898.
Learning to associate a conditioned (CS) and unconditioned stimulus (US) results in changes in the processing of CS information. Here, we address directly the question whether chemical appetitive conditioning of Lymnaea feeding behavior involves changes in the peripheral and/or central processing of the CS by using extracellular recording techniques to monitor neuronal activity at two stages of the sensory processing pathway. Our data show that appetitive conditioning does not affect significantly the overall CS response of afferent nerves connecting chemosensory structures in the lips and tentacles to the central nervous system (CNS). In contrast, neuronal output from the cerebral ganglia, which represent the first central processing stage for chemosensory information, is enhanced significantly in response to the CS after appetitive conditioning. This demonstrates that chemical appetitive conditioning in Lymnaea affects the central, but not the peripheral processing of chemosensory information. It also identifies the cerebral ganglia of Lymnaea as an important site for neuronal plasticity and forms the basis for detailed cellular studies of neuronal plasticity.  相似文献   
899.
The paper summarizes the first decade of the Developmental Trends Study, a prospective longitudinal study of 177 boys. Initially, they were referred to mental health clinics in Pennsylvania (Pittsburgh), and Georgia (Athens and Atlanta). Since 1987, the boys, their parents, and their teachers have been followed up almost annually. The study is unique because the cooperation rate of participants has remained very high over the years, psychiatric diagnoses were derived from structured interviews (especially disruptive behavior disorders), and many risk factors were measured over the years. The present paper summarizes key findings on the development of disruptive behavior, especially Oppositional Defiant Disorder, Conduct Disorder, and Attention Deficit-Hyperactivity Disorder. The paper also highlights results on risk factors and comorbid conditions of disruptive behaviors.  相似文献   
900.
Tatler BW  Wade NJ 《Perception》2003,32(2):167-184
Investigations of the ways in which the eyes move came to prominence in the 19th century, but techniques for measuring them more precisely emerged in the 20th century. When scanning a scene or text the eyes engage in periods of relative stability (fixations) interspersed with ballistic rotations (saccades). The saccade-and-fixate strategy, associated with voluntary eye movements, was first uncovered in the context of involuntary eye movements following body rotation. This pattern of eye movements is now referred to as nystagmus, and involves periods of slow eye movements, during which objects are visible, and rapid returns, when they are not; it is based on a vestibular reflex which attempts to achieve image stabilisation. Post-rotational nystagmus was reported in the late 18th century (by Wells), with afterimages used as a means of retinal stabilisation to distinguish between movement of the eyes and of the environment. Nystagmus was linked to vestibular stimulation in the 19th century, and Mach, Breuer, and Crum Brown all described its fast and slow phases. Wells and Breuer proposed that there was no visual awareness during the ballistic phase (saccadic suppression). The saccade-and-fixate strategy highlighted by studies of nystagmus was shown to apply to tasks like reading by Dodge, who used more sophisticated photographic techniques to examine oculomotor kinematics. The relationship between eye movements and perception, following earlier intuitions by Wells and Breuer, was explored by Dodge, and has been of fundamental importance in the direction of vision research over the last century.  相似文献   
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