全文获取类型
收费全文 | 49653篇 |
免费 | 2088篇 |
国内免费 | 34篇 |
出版年
2020年 | 561篇 |
2019年 | 625篇 |
2018年 | 959篇 |
2017年 | 876篇 |
2016年 | 982篇 |
2015年 | 644篇 |
2014年 | 840篇 |
2013年 | 3758篇 |
2012年 | 1531篇 |
2011年 | 1579篇 |
2010年 | 895篇 |
2009年 | 1027篇 |
2008年 | 1354篇 |
2007年 | 1370篇 |
2006年 | 1233篇 |
2005年 | 1085篇 |
2004年 | 1041篇 |
2003年 | 990篇 |
2002年 | 962篇 |
2001年 | 1702篇 |
2000年 | 1671篇 |
1999年 | 1257篇 |
1998年 | 522篇 |
1997年 | 493篇 |
1995年 | 471篇 |
1992年 | 1018篇 |
1991年 | 930篇 |
1990年 | 971篇 |
1989年 | 889篇 |
1988年 | 863篇 |
1987年 | 795篇 |
1986年 | 818篇 |
1985年 | 901篇 |
1984年 | 725篇 |
1983年 | 638篇 |
1982年 | 503篇 |
1979年 | 749篇 |
1978年 | 554篇 |
1977年 | 483篇 |
1976年 | 491篇 |
1975年 | 618篇 |
1974年 | 738篇 |
1973年 | 770篇 |
1972年 | 643篇 |
1971年 | 541篇 |
1970年 | 492篇 |
1969年 | 532篇 |
1968年 | 667篇 |
1967年 | 585篇 |
1966年 | 591篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
941.
When people are exposed to misleading details after a witnessed event, they often claim that they saw the misleading details as part of the event. We refer to this as themisinformation effect. In four experiments, involving 570 subjects, we explored the role that discrepancy detection plays in the misinformation effect. Experiment 1 showed that subjects who naturally read a post-event narrative more slowly were more resistant to the effects of misleading information contained in the narrative. In Experiment 2, subjects who naturally read more slowly were more likely to detect a discrepancy between what they were reading and what was stored in their memory. In Experiment 3, subjects who were instructed to read slowly were more likely to detect a discrepancy than were those who were instructed to read quickly. In Experiment 4, subjects who were instructed to read slowly were more resistant to misleading postevent information. Taken together, these results suggest that longer reading times are associated with a greater scrutiny of postevent information. This leads to an increased likelihood that discrepancies will be detected and that the misinformation will be resisted. 相似文献
942.
Michael C. Corballis 《Memory & cognition》1986,14(2):124-128
A task requiring the mental rotation of letters was performed either alone or during the retention interval of two short-term memory tasks. The retention of eight digits or random configurations of eight dots slowed overall reaction time on the mental-rotation task, but did not significantly alter the estimated rate of mental rotation. Conversely, performance on the memory tasks did not vary with the angle of mental rotation. These results support the view that attentional control is required to set up the mental structures required in mental rotation, but that the actual execution of the mental-rotation component can be relegated to subordinate systems that do not compete for attentional resources. 相似文献
943.
In two experiments, we investigated the factors that influence the perceived similarity of speech sounds at two developmental levels. Kindergartners and second graders were asked to classify nonsense words, which were related by syllable and phoneme correspondences. The results support the existence of a developmental trend toward increased attention to individual phonemic segments. Moreover, one significant factor in determining the perceived similarity of speech sounds appears to be the position of the component correspondences; attention to the beginning of utterances may have developmental priority. An unexpected finding was that the linguistic status of the unit involved in a correspondence (whether it was a syllable or a phoneme) did not seem particularly important. Apparently, the factors which contribute to the perceived similarity of speech sounds in the classification task are not identical to those which underlie performance in explicit segmentation and manipulation tasks, since in the latter sort of task, syllables are more accessible than phonemes for young children. The present task may tap a level of processing that is closer to the one entailed in word recognition and lexical access. 相似文献
944.
Predicting which words get recalled: Measures of free recall,availability, goodness,emotionality, and pronunciability for 925 nouns 总被引:3,自引:0,他引:3
To investigate the properties that make a word easy to recall, we added to existing norms for 925 nouns measures of availability, goodness, emotionality, pronunciability, and probability of recall in multiple-trial free recall. Availability, imagery, and emotionality were found to be the best predictors of which words were recalled. This result, which is stable across recall data collected in three separate laboratories, argues for the importance of availability as a predictor of recall and questions the role of the correlated variables of word frequency and meaningfulness. Consistent with earlier work on a smaller sample of words, six factors describe the numerous properties of words studied by psychologists. The six factors are composed of variables based on orthography, imagery and meaning, word frequency, recall, emotionality, and goodness. 相似文献
945.
Punctuation in 20 radio homilies by four speakers accounted for 76% of pause time and 64% of pause number. Pause duration varied systematically according to punctuation type. Commas accounted for 82% of punctuated positionsnot used for pausing.RRelevance for theories of text unitization is discussed. Both typographical and temporal measures are compared with a similar corpus of German homilies. 相似文献
946.
Intermediate prepositional logics we consider here describe the setI() of regular informational types introduced by Yu. T. Medvedev [7]. He showed thatI() is a Heyting algebra. This algebra gives rise to the logic of infinite problems from [13] denoted here asLM
1. Some other definitions of negation inI() lead to logicsLM
n
(n ). We study inclusions between these and other systems, proveLM
n
to be non-finitely axiomatizable (n ) and recursively axiomatizable (n < ). We also show that formulas in one variable do not separateLM
from Heyting's logicH, andLM
n
(n < ) from Scott's logic (H+S). 相似文献
947.
Santosh C. Panda 《Synthese》1986,67(2):259-271
The axioms adopted by Packard (1981) and Heiner and Packard (1983) for plausibility ranking of sets of statements are critically examined. It is shown that the informational requirement of the Heiner-Packard (1983) framework is much stronger than Packard's (1981) framework and hence both axiomatic setups are examined separately. A characterization of the leximin rule is provided in Packard's framework and the nonintuitive implications of the Heiner-Packard (1983) axioms are discussed. It is also demonstrated that in both frameworks, minor variations of some of the axioms convert the characterization results into logical impossibilities.I am grateful to Prof. P. K. Pattanaik for many helpful suggestions. 相似文献
948.
Two different concepts of distinguishability are often mixed up in attempts to derive in quantum mechanics the (anti)symmetry of the wave function from indistinguishability of identical particles. Some of these attempts are analyzed and shown to be defective. It is argued that, although identical particles should be considered as observationally indistinguishable in (anti)symmetric states, they may be considered to be conceptually distinguishable. These two notions of (in)distinguishability have quite different physical origins, the former one being related to observations while the latter has to do with the preparation of the system. 相似文献
949.
Hans P. W. Vermeeren 《Synthese》1986,69(3):273-290
Controversies, i.e., multiple theory confrontations, may have a strong impact on the development of science. By an analysis of the so-called “resonance controversy” in chemistry the view that controversies and their resolution differ considerably from the process of theory succession is defended. It is argued that controversies are symptomatic of foundational problems, produce theory-scattering or domain-splitting, and induce ontological shifts. An explication is given of the role of existence claims and the applicability of Ockham's Razor in the resolution of controversies. The requirement of a realistic interpretation of theories at all times, as defended by some philosophers, is criticised. 相似文献
950.