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71.
Despite its frequent use to assess effects of environmental and pharmacological variables on short-term memory, little is known about the development of delayed matching-to-sample (DMTS) performance. This study was designed to examine the dimensions and dynamics of DMTS performance development over a long period of exposure to provide a more secure foundation for assessing stability in future research. Six pigeons were exposed to a DMTS task with variable delays for 300 sessions (i.e., 18,000 total trials; 3,600 trials per retention interval). Percent-correct and log-d measures used to quantify the development of conditional stimulus control under the procedure generally and at each of five retention intervals (0, 2, 4, 8 and 16-s) individually revealed that high levels of accuracy developed relatively quickly under the shorter retention intervals, but increases in accuracy under the longer retention intervals sometimes were not observed until 100-150 sessions had passed, with some still increasing at Session 300. Analyses of errors suggested that retention intervals induced biases by shifting control from the sample stimulus to control by position, something that was predicted by observed response biases during initial training. These results suggest that although it may require a great deal of exposure to DMTS prior to obtaining asymptotic steady state, quantification of model parameters may help predict trends when extended exposure is not feasible. 相似文献
72.
Hyperactivity has attracted a large amount of research interest in recent years. Here we review developments in genetic research and in research testing psychological theories of the condition. Family, adoptee and twin studies indicate a strong role for genetic factors in the etiology of hyperactivity. Evidence is emerging also from molecular genetic studies, implicating specific genes that may be involved. At the level of cognitive functioning, a divided, focused or sustained attention deficit does not seem to be a core deficit in hyperactivity. Although children with hyperactivity often perform poorly on certain executive function tasks, there is disagreement about the interpretation of these findings. The association reported in some studies between a slow inhibitory process and hyperactivity may reflect a generally slow, variable in speed and inaccurate pattern of responding. Hypotheses about psychological mechanisms such as state regulation or delay aversion provide alternative, and particularly encouraging, interpretations of the findings. We discuss the possible integration of the two lines of research—those of genetic research and research on psychological mechanisms. 相似文献
73.
An alternating least squares method for iteratively fitting the longitudinal reduced-rank regression model is proposed. The method uses ordinary least squares and majorization substeps to estimate the unknown parameters in the system and measurement equations of the model. In an example with cross-sectional data, it is shown how the results conform closely to results from eigenanalysis. Optimal scaling of nominal and ordinal variables is added in a third substep, and illustrated with two examples involving cross-sectional and longitudinal data.Financial support by the Institute for Traffic Safety Research (SWOV) in Leidschendam, The Netherlands is gratefully acknowledged. 相似文献
74.
近现代中国文化名人人格的扩展研究 总被引:3,自引:0,他引:3
本研究在前次研究的基础上,以中国近现代文化名人为研究对象,运用问卷调查、评定量表、个案及其主题分析等方法,对该群体的总体人格特征作出了描述,并从性别、出生年代、活跃领域等三个方面比较了各类型集团人格特征的异同,从而揭示了个人选择与环境,人格特征之间密不可分的联系。 相似文献
75.
基于工作要求-资源理论, 本研究探讨了两种社交媒体使用目的对员工工作绩效影响的内部作用机制, 进而分析两种社交媒体使用目的对员工工作绩效的影响效果。通过369份“领导者-下属”匹配数据, 研究发现:(1)基于工作、社交的社交媒体使用均促进员工工作绩效; (2)基于工作、社交的社交媒体使用均通过工作投入影响工作绩效, 基于社交的社交媒体使用还通过关系冲突影响工作绩效; (3)社交媒体的工作使用和社交使用对员工工作绩效的影响存在相互替代关系。本研究结果不仅从理论上拓展了社交媒体使用的研究视角, 为后续研究提供新的理论框架, 同时通过比较分析为组织管理社交媒体使用提供了新思路。 相似文献
76.
Background: Cognitive models propose that attentional biases to threat contribute to the maintenance of social anxiety disorder (SAD). However, the specific characteristics of such biases are still object to debate.Objectives: The current study aimed to disentangle effects of trait and state social anxiety on attention allocation towards social stimuli.Methods: Participants with SAD (n?=?67) and healthy controls (n?=?62) completed three visual search tasks while their eye movements were recorded. Half of the participants in each group were randomly assigned to a state anxiety induction.Results: Contrary to our predictions, neither trait nor state social anxiety was associated with a facilitated attention to or a delayed disengagement from threat. However, participants with SAD did show reduced fixation durations for threatening stimuli, indicating an avoidance of threat. Induction of state anxiety led to an increased distractibility by threat.Conclusions: We suggest that attention allocation in SAD is characterized by an avoidant rather than a vigilant attentional bias. Accordingly, our results contradict previous results that associate SAD with facilitated attention to threat and existing approaches to modify attentional biases, that aim to decrease attention towards threatening stimuli. 相似文献
77.
姬芳序 《医学与哲学(人文社会医学版)》2023,44(9):69-74
瘟疫贯穿人类历史发展始终。近代以降,由于列强势力深入中国各地,围绕瘟疫防治而产生的华洋互动日趋频繁。一方面,外侨主导的防疫事业引发了中国社会各阶层收回防疫主权的外交诉求;另一方面,列强以防疫之名行侵略之实的行为使得华洋之间围绕国权展开了艰难博弈。在此过程之中,近代中国政府通过完善其行政能力,更有力地介入到防疫领域的管理中,推动了防疫事业的制度化发展,并以外交的方式维护公共卫生领域的国权,从而在应对公共卫生事件中逐步走向成熟。
相似文献78.
79.
Abstract. The presence of a basic and general form of creativity in people is investigated through experiments with music. The results indicate that "generative" creativity—-the ability to spontaneously generate a music by varying a basic set of musical elements—is a basic human endowment, unlike "constructive" creativity—-the type of creativity exhibited by composers and other artists—-which is the result of training and the spehal development of faculties. Generative creativity's coming to the fore in contemporary people would contribute to the development of the personality and help bring about more fulfilled, better balanced people and societies. 相似文献
80.
结核病诊治进展与科技革命 总被引:2,自引:0,他引:2
现代科技革命极大地促进了结核病各方面的发展.微生物学和免疫学的发展,揭示了结核病的病因、发病机制、病理生理的本质,分子生物学技术使结核病的基础研究不仅停留在器官、细胞水平,而是深入到蛋白质、核酸、基因的水平;基因治疗的方法可望从根本上治疗结核病.高新技术的产物如X线照片、电子计算机断层扫描、纤维支气管镜检查和新药的出现等极大地提高了临床诊治的能力.借助于各种先进的医疗设备而进行精确的诊断,基因治疗将成为一种崭新的治疗手段. 相似文献