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841.
The accommodative response to subthreshold blur and to perceptual fading during the Troxler phenomenon 总被引:2,自引:0,他引:2
A study is reported which shows that accommodation can be stimulated by a blur stimulus which is below the threshold for visual perception. It is also shown that perceptual fading of the target, caused by stabilization of the retinal image (Troxler phenomenon), can eliminate the accommodative response causing it to default to its resting level. The first finding suggests a way in which the visual system can filter the percept of blur out of our conscious awareness and still effectively utilize the blur as a steady-state error for the accommodative control system. The second finding is consistent with a locus for the Troxler phenomenon in the early afferent part of the visual pathway, ie the retinal ganglion cells. 相似文献
842.
Static depiction of movement 总被引:1,自引:0,他引:1
A number of pictorial devices were compared in order to assess their relative effectiveness in depicting events. Effectiveness, as measured by a rating task, did not seem to be a function of the classification of a device as natural or metaphorical. Rather, it depended on whether a given device highlighted a distinctive aspect of a particular event (running, jumping, or moving), or simply modified the event. This observation was buttressed by the existence in a forced-choice task of a category boundary for depictions of running (pictures with a certain device were seen as running, those without it were not) but not for moving or jumping. Even preschool children displayed some understanding of metaphorical devices. They chose figures with those devices as running faster than the experimental standard. Results are discussed in the context of Kennedy's characterization of pictorial metaphors and Gibson's framework for understanding the relationship between pictorial and environmental information. 相似文献
843.
Earlier studies have shown the girls spend more time than boys in activities that are highly structured by adults. Structured activities may encourage feminine sex-typed behaviors such as compliance to adults; low-structure activities may encourage masculine sex-typed behaviors such as independence and assertiveness. In the present study the effects of high or low levels of adult structuring on children's social behavior during preschool free-play activities were tested in a field experiment carried out during an entire semester in one preschool classroom. For the first 15 minutes of free play, children were assigned to high- or low-structure activities. As predicted, when children were in high-structure activities, they exhibited high rates of bids for recognition and compliance to adults; in low-structure activities, they exhibited peer-directed leadership, bids for recognition, and compliance. There were no generalized effects of these treatments on their subsequent free choice of activities or social behavior. The study demonstrates powerful effects of naturally occurring variations in children's play activities on sex-typed social behaviors. 相似文献
844.
845.
San Diego suicide study: comparison of gay to straight males 总被引:1,自引:0,他引:1
Previous large studies of completed suicides have not considered sexual orientation in their data analyses. In this study, data from the known homosexual subpopulation (13 males, aged 21-42) in a series of 283 suicides were examined. They were compared with all other aged male suicides 21-42 (n = 106). Both groups showed considerable substance abuse plus a variety of other psychiatric diagnoses. Both also had a high frequency of relationship difficulties near the time of death. Gays who committed suicide did not have a history of more police trouble and were no more likely to be living alone than the comparison group. They did not have more prior suicide attempts or previous psychiatric treatment. We conclude that, among the factors examined here, there appears to be little difference between gay and heterosexual male suicides. 相似文献
846.
Reasoning on social dilemmas varying in emotional saliency: an adult developmental perspective 总被引:2,自引:0,他引:2
F Blanchard-Fields 《Psychology and aging》1986,1(4):325-333
The purpose of this study was to provide age-comparative evidence of social cognitive reasoning in adulthood, as mediated by the emotional saliency of tasks tapping postformal reasoning. Specifically, the tasks focused on the ability to resolve discrepant accounts of the same event sequence. It was assumed that less mature thinking may be more evident in reasoning contexts in which emotional factors play a major role. A postformal coding scheme was used to assess levels of reasoning in an interpersonal context. Tasks were administered to 60 subjects--adolescents and young and middle-aged adults. Measures of formal operations, ego level, and verbal ability were also administered. An interaction was found between age and degree of emotional saliency of the task for reasoning level. Specifically, adolescents performed less well on tasks higher in degree of emotional saliency. In addition, developmental differences in postformal reasoning as a function of age and ego level were found. 相似文献
847.
Younger adult students between 19 and 24 years of age (M = 21.3 years), older adult students between 61 and 76 years of age (M = 67.9 years), and older adult nonstudents between 62 and 76 years of age (M = 68.5 years) were assessed for health (self-ratings of physical and mental health), social functioning (self-ratings of physical and mental activity, perceived role activity level, perceived roles, locus of control, and age-norm expectations), and cognitive functioning (Wechsler Adult Intelligence Scale-Revised vocabulary and block design, and paired associate memory). Age differences were observed in self-ratings of health, social roles, intellectual performance, and memory. No student status differences were observed. The results are discussed in terms of plasticity of intellectual function and characteristics of student status in later adulthood. 相似文献
848.
Modest decrements in both taste threshold sensitivity and, more recently, suprathreshold sensitivity have been associated with the aging process. The present study was designed to investigate the existence of changes in preference for various concentrations of single tastes and of the same single tastes in more complex chemosensory mixtures. In this study, 300 participants from three different age groups (18-26, 32-45, over 65) rated for pleasantness four concentrations of sodium chloride, sucrose, and citric acid presented in both aqueous and beverage bases. Results showed significant effects of age, stimulus background, stimulus, concentration, and of several interactions, and they suggest that elderly subjects find salt and sugar pleasanter at higher concentrations than younger subjects do. 相似文献
849.
Fluid intelligence belongs to that cluster of intellectual abilities evincing aging loss. To examine further the range of intellectual reserve available to aging individuals and the question of replicability in a new cultural and laboratory setting, 204 healthy older adults (mean age = 72 years; range = 60-86) participated in a short-term longitudinal training study. For experimental subjects, 10 sessions consisted of cognitive training involving two subability tests (Figural Relations, Induction) of fluid intelligence. The pattern of outcomes replicates and expands on earlier studies. Older adults have the reserve to evince substantial increases in levels of performance in fluid intelligence tests. Transfer of training, however, is narrow in scope. Training also increases accuracy of performance and the ability to solve more difficult test items. Difficulty level was estimated in a separate study, with a comparable sample of N = 112 elderly adults. Future research is suggested to examine whether intellectual reserve extends to near-maximum levels of performance. 相似文献
850.
Barbara E. DiCocco L.C.S.W. 《Contemporary Family Therapy》1986,8(1):50-61
When presented with a behavioral problem or symptom expression that involves two systems, such as a serious school-related problem, the therapist needs to design an approach that will intervene effectively and expeditiously in both systems. This paper offers a guide to stages of problem escalation and therapeutic intervention that is intended to aid the problem-solver's thinking processes in approaching a troubled situation that involves two systems, the school and the home. 相似文献