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91.
Ghorashi SM Smilek D Di Lollo V 《Journal of experimental psychology. Human perception and performance》2007,33(1):124-136
J. S. Joseph, M. M. Chun, and K. Nakayama (1997) found that pop-out visual search was impaired as a function of intertarget lag in an attentional blink (AB) paradigm in which the 1st target was a letter and the 2nd target was a search display. In 4 experiments, the present authors tested the implication that search efficiency should be similarly impaired (steeper search slopes at shorter lags). A conventional AB deficit was found, but, contrary to expectations, search slopes were invariant with lag. These results suggest that no search can be carried out during the period of the AB. Instead, the search is postponed until after the 1st target has been processed. The authors conclude that efficient visual search cannot be carried out unless the visual system is configured appropriately for the search task. If the initial configuration is inappropriate, processing of the 2nd target is held in abeyance until the system has been suitably reconfigured. 相似文献
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Stimulus intensity and duration of visible persistence have been found to vary directly in some studies but inversely in others. Hawkins and Shulman (1979) have proposed that this inconsistency can be resolved by separating the studies that employed a decrement-threshold measure of persistence (Type I measure) from those that measured the total duration of persistence (Type II measure). They suggested that Type I measures yield an inverse relationship, whereas Type II measures yield a direct relationship between intensity and persistence. Hawkins and Shulman's model is incomplete in ways that are easily remedied. However, the model is totally contradicted by the experimental evidence. A new resolution of the inconsistent results is proposed in terms of retinal afterimages. 相似文献
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Temporal aspects of early visual information processing were studied developmentally in good and in poor reading male subjects ranging in age from 7 to 13 years. Forced-choice temporal integration and backward masking tasks, respectively, were utilized to assess duration of visual persistence and of relative rate of visual information processing. The results did not reveal differences in either visual persistence or processing rate in relation to reading ability at any age level studied. However, processing rate was found to increase markedly with chronological age in both the good and the poor readers while visual persistence did not vary significantly. The findings were discussed in relation to earlier work and in relation to current theoretical formulations of visual information processing. 相似文献
95.
J. A. Parkinson A. C. Roberts B. J. Everitt P. Di Ciano 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》2005,58(1):19-30
The associative mechanisms responsible for the efficacy of Pavlovian stimuli during first- and second-order conditioning have been extensively studied, but little is known about the representations underlying instrumental conditioned reinforcement. The present study investigated the associative structure underlying conditioned reinforcement, by employing an unconditioned stimulus (US) devaluation procedure on a commonly used instrumental task: the acquisition of a new response with conditioned reinforcement. Whilst US-directed behaviour was abolished following devaluation, the conditioned stimulus acting as a conditioned reinforcer supported the acquisition of instrumental responding. In this preparation then, the conditioned reinforcer appears to be impervious to devaluation of its associated US, suggesting that the underlying representation maintaining behaviour is independent of the current value of the US and may reflect the activation of a central appetitive motivational state. 相似文献
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分析我国城市一二级公立医院转型为康复医院、老年护理院等接续性医疗机构政策的内外部特征,为后续政策的制定与完善提供参考。通过构建政策工具、政策利益相关者、政策力度三维政策分析框架,对相关政策进行多维分类分析。得出相关政策发文量呈波动增长趋势;环境型政策工具使用过溢,供给型政策工具内部结构配置失衡,需求型政策工具应用匮乏;对不同政策利益相关方的关注度存在差异;政策顶层设计欠缺,整体政策效力不高。建议优化政策工具使用,平衡各利益相关方需求,完善政策体系内容。
相似文献99.
通过检索国内外6个文献数据库以获取发表于2010年1月~2020年7月研究相关的文献,并对干细胞来源的生物材料采集的供者健康风险进行了系统性综述。50篇相关文献分析显示,在许多情况下,生物材料采集可使供者承受健康风险,包括麻醉、粒细胞集落刺激因子或促排卵药物使用、中心静脉导管放置、穿刺等带来的风险。此外,生物材料采集还可影响供者的心理健康。根据上述发现,建议干细胞来源的生物材料采集需要严格的伦理管控,以保障生物材料供者的健康权益。
相似文献100.
新型冠状病毒肺炎尚无治疗特效药和疫苗。在继续加强防控的同时,把有限的资源优先放在探索对重症和危重症患者的支持性治疗,积极建立和完善对重症、危重症患者及其家属的缓和医疗等方面,有利于患者群体利益最大化,经得起伦理辩护。缓和医疗有助于改善患者预后,降低住院病死率,有效缓解患者濒死痛苦;对医患双方而言,如果死亡已无可避免,帮助临终者走得平安、少些痛苦,是医学对患者最后的人文关怀。 相似文献