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81.
Subject-specific periods of fluent reading responses of three adult stutterers were positively reinforced with the presentation of a dime. Subjects were run individually through a sequence of two base rate, two experimental, and two extinction sessions, each session lasting 45 min. Periods of fluent reading responses increased during the experimental condition for each of the three subjects. When the reinforcer was withdrawn during the extinction condition, the frequency of fluent periods showed a decrease. Concomitantly, disfluencies decreased during the experimental condition and they increased during the extinction condition. The clinical implications of fluency manipulation as against disfluency manipulation are discussed.  相似文献   
82.
83.
A Greek-born aphasic who had been able to speak four languages (Romanian, Russian, Greek, German) was tested quantitatively for verbal expression (standard interview indexes) and verbal reception (fifth part of the Token Test). The form of aphasia (qualitative aspect) was found to be identical for all four languages. Quantitatively, his performance in the four languages was different, with the languages used most during the past 20 years (Romanian and Russian) being less impaired. Nevertheless, verbal reception was equally impaired quantitatively in all four languages. Treatment with semantic-syntagmatic methods performed in Romanian had a beneficial effect on speech in the other languages as well. The authors feel that the expressive disturbance noted in aphasia reflects involvement of deep as well as of surface structures of language, but the receptive disturbance reflects involvement of the deep structures only. This may account for quantitative discrepancies in expression without discrepancy in reception among the four languages, as well as the qualitatively identical features of the disturbance in verbal expression and reception.  相似文献   
84.
85.
To learn more about the mechanism (or mechanisms) involved with postresponse stimulus processing during discrimination learning, a series of studies was conducted with monkeys to determine why the combined relevant and irrelevant stimuli impair learning more than irrelevant stimuli appearing alone. It was found that: (a) the greater size and complexity of the combination of stimuli were not responsible for the greater deficit, while the presence of the relevant stimuli (SD and SΔ) within the stimulus combination apparently was; (b) the more similar the postresponse irrelevant stimuli were to the relevant stimuli the greater the deficit that resulted; and (c) monkeys that had earlier learned to discriminate the relevant and irrelevant features of a combination showed no learning impairment when this same stimulus combination was later presented after the response during a new learning problem. These results were interpreted as evidence that: (1) processes associated with learning a discrimination problem do not end with the execution of a choice response; (2) postresponse stimuli produce greater impairment in discrimination learning when they are distorted versions of the relevant stimuli; and (3) the impairment resulting from postresponse irrelevant stimuli occurs primarily when this misinformation is processed and misperceived as being relevant to learning the discrimination problem.  相似文献   
86.
The associations formed in the components of a multiple schedule can be classified as (1) stimulus-response (S-R) associations and (2) stimulus-reinforcer (S-SR) associations. The present experiments sought to determine the individual contribution of these S-R and S-SR associations to stimulus control by manipulating them independently. Responses postponed shocks by 25 sec in the presence of a tone alone and a light alone in all experiments. The contingencies programmed in the absence of both tone and light established a reference for the S-R and S-SR associations in tone and in light. All four possible combinations of signalling response increase or decrease together with incentive increase or decrease were studied. Although the influence of the contingencies operating in the absence of tone and light was difficult to detect from response rates in tone or light, presenting tone and light together revealed clear effects. Response rates in tone and light together relative to those in either alone depended upon the contingency operating in the absence of tone and light. Stimulus-response and stimulus-reinforcer associations appeared to counteract each other when in opposition and combine together to enhance each other when in agreement. This suggested that the associations of a stimulus to response and to incentive combine algebraically in determining stimulus control. An algebraic analysis in terms of the S-R and S-SR associations conditioned to the stimulus elements comprising the training and test stimuli accounted for the observed patterns of data.  相似文献   
87.
In two experiments, rats received noncontingent pairings of two stimuli with food reward, one paired with small reward and the other with large reward, and received bar press training with large reward or with small reward. When the noncontingent stimuli (NS) were presented for test during subsequent rewarded bar pressing and during early extinction of bar pressing, responding for each group was faster in the presence of the NS which was paired with the same reward magnitude that group received in bar press training than to the NS which had been paired with a different reward magnitude. As extinction progressed, all groups responded more slowly in the presence of the NS which had been paired with the large reward than in the presence of the NS which had been paired with small reward. These results were interpreted as indicating that responding in the presence of an NS depends on: (i) whether the reward expectancy elicited by the NS has been conditioned to the instrumental response, and (ii) the relationship between the reward expected in the presence of the NS and that received in test.  相似文献   
88.
为考察阅读范文是否能够提高三年级小学生记叙文写作的成绩,在建立低年级小学生记叙文写作评价指标的基础上,选择1篇完整范文并设计8篇不同类型的不完整范文,选取300名三年级小学生为被试进行了实验研究。实验结果表明:(1)阅读完整范文和联结内容式、补充中间式、补充开头式、补充结尾式等不完整范文能够明显提高小学生记叙文写作结构分项的成绩,阅读其他4种类型的不完整范文作用不明显。(2)阅读完整的和8种不完整范文均能明显提高小学生在记叙文写作内容分项的成绩。(3)除了补充开头式、补充中间和结尾式两种不完整范文之外,阅读其他7种范文均能明显提高作文词句分项的成绩。(4)阅读范文对避免写作中出现错别字、错用标点符号和病句无显著作用。  相似文献   
89.
网络医疗的发展和思考   总被引:1,自引:0,他引:1  
随着科学技术、网络技术迅猛的发展,许多互联网业务如网上求医、网上购药、网上保健也日渐火热,成为人们防治疾病的又一手段。网络医疗是网络科技与医疗技术结合的产物,在信息高速发展的今天,它已成为医学交流中一道亮丽的风景线,各国都在不遗余力发展自己的远程医疗系统,这无疑将推动医学模式的进步。然而作为一种新的医疗手段,网络医疗目前仍存在着诸多的弊端和问题,这些问题反过来又可制约网络医疗的发展,因此必须在技术、政策、法律各方面予以完善,使之更好地服务于人类。  相似文献   
90.
社会医疗保险道德风险博弈与防控措施研究   总被引:7,自引:1,他引:7  
通过对社会医疗保险道德风险产生原因与特征的探讨,根据不完全信息重复博弈模型对社会医疗保险道德风险进行了系统分析,据此提出了社会医疗保险道德风险的防控措施,以期实现对道德风险的有效防控,提高社会医疗保险基金的安全。  相似文献   
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