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161.
Four conditions were used to investigate developmental trends in the ability to establish and use a color set to direct the selective processing of pictures. In three conditions, 6-year-old, 9-year-old, and adult subjects viewed a series of pairs of pictures, with one red and one black line drawing in each pair. Subjects were asked to look either at the red pictures only, the black pictures only, or both pictures. In a fourth condition, subjects viewed a series of singly presented red and black pictures. Pictures of both colors were included in a subsequent recognition memory test. At all ages recognition memory was comparable for pictures of each color in the both and single conditions but was higher for pictures of the specified color in the selective red and selective black conditions. There was no evidence at any age that memory for pictures of the specified color was decreased by the presence of the second picture. These results, showing roughly comparable selectivity at all ages, were discussed in relation to findings of developmental trends in selective attention on more “traditional” central-incidental learning tasks.  相似文献   
162.
163.
Given sequences of digits with temporally equidistant acoustic onsets, listeners do not perceive them as isochronous (Morton, Marcus, & Frankish, 1976). In order for the sequences to be perceptually isochronous, systematic departures from acoustic isochrony must be introduced. These acoustic departures are precisely those that talkers generate when asked to produce an isochronous sequence (Fowler, 1979), suggesting that listeners judge isochrony based on acoustic information about articulatory timing. The present experiment was an attempt to test directly whether perceptually isochronous sequences have isochronous articulatory correlates. Electromyographic potentials were recorded from the orbicularis oris muscle when speakers produced sequences of monosyllables “as if speaking in time to a metronome.” Sequences were devised so that lip-muscle activity was related to the syllable-initial consonant, the stressed vowel, or the stressed vowel and final consonant. Results indicate that isochronous muscular activity accompanies both isochronous and anisochronous acoustic signals produced under instructions to generate isochronous sequences. These results support an interpretation of the perceptual phenomenon reported by Morton et al. to the effect that listeners judge isochrony of the talker’s articulations as they are reflected in the acoustic signal.  相似文献   
164.
Previous experiments show that the opportunity to engage in schedule-induced responding is reinforcing. In this experiment, the reinforcing strength of schedule-induced drinking was measured. Four rats were trained on a concurrent-chain schedule. The two terminal links provided food pellets on identical fixed-time schedules. In addition, one terminal link also provided the opportunity to press a button that operated a water dipper. In this link, the rats showed polydipsic drinking. Button-pressing rate for polydipsic drinking was a bitonic function of pellet rate, and it was possible to describe the relationship with a slightly modified version of the matching equation for primary reinforcement. This equation also closely fit the data from other studies. Initial-link response rates, however, did not appear to be influenced by the availability of water in the terminal links. Control conditions suggested that the reinforcing strength of polydipsia was strongly bound to the context provided by periodic food reinforcement.  相似文献   
165.
Does varying the spacing of repetitions over intervals as long as 1 week aftect recall? The answer from three experiments is yes. Subjects incidentally processed words repeated within a single list and words repeated in separate lists at list spacings of up to 1 week. Memory was tested by free recall shortly after the second presentations or after retention intervals of up to 1 week. Recall of the words repeated across separate lists conformed to a proportionality rule. When the retention interval is short relative to the spacing intervals, performance is inversely related to spacing. When the retention interval is a large proportion of the spacing intervals, performance is directly related to spacing. Does varying the spacing of repetitions within a single list affect recall after a retention interval of 2 weeks? The answer depends on the processing used while studying the words. Processing that generated interitem associations resulted in a within-list spacing effect even after a 2-week retention interval. Without the interitem associations, the effect was absent after a 1-day retention interval. Most of these findings were explained by examining the changing relationship between the retrieval context and the context stored during study.  相似文献   
166.
167.
Many families, when presented with the option of family therapy, are less than eager to participate. This paper comprises the second and third parts of a series on engaging “resistant” families. 1 1 The first paper in this series, authored by J. M. Van Deusen, M. D. Stanton, S. M. Scott, and T. C. Todd, is entitled “Engaging “Resistant” Families in Treatment: I. Getting the Drug Addict to Recruit His Family Members” and appeared in the International Journal of the Addictions 15 (7): 1069–1089, 1980. A revised and expanded version of Part II is presented in M.D. Stanton, T. C. Todd, and Associates, The Family Therapy of Drug Abuse and Addictions New York, Guilford, in press.
Part II presents 21 principles and a number of techniques and strategies that have been developed for successfuly recruiting such families. These techniques should be applicable for engaging resistant families with all types of presenting problems. Part III provides an analysis of the important variables involved, along with data on cost efficiency and administrative costs. It was found that when therapists had administrative control of their cases, serving in dual roles as both therapists and drug counselors, the recruitment effort was (a) more effective (i.e., complete families, including both parents or parent surrogates, were recruited in 77 per cent of the cases), and (b) twice as cost efficient. Two-thirds of the non-engaged families were not recruited because the index patient would not allow family members to be contacted. Black families were more difficult to recruit than whites. Data on cost efficiency and on the actual administrative costs of recruiting families are also provided. We conclude that the engagement process requires a revision in therapeutic philosophy, since such families are often desperately in need of help but are unavailable unless therapists make a special effort to reach them.  相似文献   
168.
Septal correlates of conditioned inhibition and excitation in rats   总被引:3,自引:0,他引:3  
Multiple-unit activity was recorded in the lateral septum of rats during Pavlovian differential conditioning. In Experiment 1, one group of animals received a classical aversive discrimination paradigm, while another group was presented with a control procedure in which the unconditioned stimuli (shocks) were administered randomly with regard to the conditioned stimuli. Septal unit activity increased during presentations of the conditioned inhibitor and was markedly suppressed during presentations of the conditioned excitor in the conditioning-group animals and not in the control animals. Baseline activity remained unchanged in the conditioning group but was suppressed in the random control group. Furthermore, termination of the aversive stimuli was marked by a burst of firing in the conditioning group, but no such rebound was seen in the control group. In Experiment 2, a classical appetitive discrimination paradigm was given, in which septal unit activity was found to increase in the presence of the conditioned excitor and was suppressed in the presence of the conditioned inhibitor. The results are interpreted as indicating a role for the septum in the relief of aversive states.  相似文献   
169.
Several researchers who have compared the performance of dyslexic and normal-reading children on a variety of different tasks have suggested that dyslexic children may have subtle deficits in the phonemic analysis of spoken as well as written language. Thus it is of interest to know how children who have extraordinary difficulty learning to read can perform explicity auditory-phonetic tasks. Seventeen dyslexic children (10 years of age) and a group of 17 controls were administered tests of identification and discrimination of synthesized voiced stop consonants differing in place of articulation. These were tests of the type used to study categorical perception in adults, adapted for use with young children. Significant differences between dyslexics and controls were found in both kinds of tasks; the pattern of identification and discrimination differences suggests an inconsistency in the dyslexics' phonetic classification of auditory cues. A significant relationship was found between reading level and speech discrimination.  相似文献   
170.
The role of the vocal channel of emotion expression in infancy has been neglected in developmental theory. The present review describes the ontogenetic course of vocal emotional expression as exhibited by human and infrahuman primate young and considers its dynamic relationship to the facial and bodily components of expression. The infant's encoding of negative and positive emotion expression is discussed within a developmental framework. In addition, this review assesses the impact of early social influences. It is concluded that early patterns of infant vocal emotional expression are probably biogenetically determined and that there may be certain universal vocal signals. However, data derived from studies of dyadic interaction indicate that the transition from raw affect expression in early infancy to a more modulated pattern later on is a product not only of neuromuscular maturation but of maternal coaching in affective expression as well.  相似文献   
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