全文获取类型
收费全文 | 67437篇 |
免费 | 2818篇 |
国内免费 | 31篇 |
专业分类
70286篇 |
出版年
2020年 | 852篇 |
2019年 | 1021篇 |
2018年 | 1429篇 |
2017年 | 1425篇 |
2016年 | 1518篇 |
2015年 | 1084篇 |
2014年 | 1335篇 |
2013年 | 6137篇 |
2012年 | 2414篇 |
2011年 | 2436篇 |
2010年 | 1488篇 |
2009年 | 1530篇 |
2008年 | 2127篇 |
2007年 | 2084篇 |
2006年 | 1960篇 |
2005年 | 1680篇 |
2004年 | 1687篇 |
2003年 | 1652篇 |
2002年 | 1561篇 |
2001年 | 2141篇 |
2000年 | 2001篇 |
1999年 | 1538篇 |
1998年 | 792篇 |
1997年 | 717篇 |
1996年 | 759篇 |
1995年 | 695篇 |
1994年 | 681篇 |
1993年 | 657篇 |
1992年 | 1230篇 |
1991年 | 1145篇 |
1990年 | 1108篇 |
1989年 | 1054篇 |
1988年 | 1010篇 |
1987年 | 959篇 |
1986年 | 970篇 |
1985年 | 1043篇 |
1984年 | 870篇 |
1983年 | 751篇 |
1982年 | 587篇 |
1981年 | 586篇 |
1979年 | 840篇 |
1978年 | 663篇 |
1977年 | 568篇 |
1976年 | 564篇 |
1975年 | 693篇 |
1974年 | 778篇 |
1973年 | 782篇 |
1972年 | 656篇 |
1971年 | 601篇 |
1968年 | 635篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
9 stutterers and 9 nonstutterers were administered a dichotic digits test under conditions of free recall and directed attention. Analysis indicated right-ear preference for both groups and no differences between the free recall and directed listening conditions. Results are discussed in relation to previous studies in which dichotic digit-stimuli were presented to stutterers. 相似文献
952.
6 adult subjects (3 men, 3 women) produced highly similar spontaneous speech utterances in quiet and with 90-dB SPL white noise. The frequency of occurrence of perceptual judgments of primary stressing in an utterance was not affected by the masking noise. This finding supplements our previous report that variability for stress production of fundamental frequency (fo) during spontaneous speech was preserved under short-term auditory disruption. Also, it adds further support to the contention that fo is under open-loop regulation. 相似文献
953.
954.
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
955.
Locus of inhibition effects in the priming of lexical decisions: pre- or postlexical access? 总被引:1,自引:0,他引:1
The lexical decision task has been employed to investigate the effects of semantic context on word recognition. A frequent finding from the task is that “word” responses are slower when the target is preceded by an unrelated word than when it is preceded by a neutral stimulus. This inhibition effect has been interpreted as indicating that the unrelated prime interferes with word-recognition processes operating on the target. In three experiments, the effects of unrelated primes were compared for a lexical decision and word naming task. Although large inhibition effects were found for the lexical decision task in all experiments, no inhibition effects were observed for the naming task. The results are interpreted as demonstrating that inhibition effects in the lexical decision task are not on recognition processes; rather they are located at processes operating after recognition of the target has occurred. 相似文献
956.
In some recent papers, the authors and Peter Gärdenfors have defined and studied two different kinds of formal operation, conceived as possible representations of the intuitive process of contracting a theory to eliminate a proposition. These are partial meet contraction (including as limiting cases full meet contraction and maxichoice contraction) and safe contraction. It is known, via the representation theorem for the former, that every safe contraction operation over a theory is a partial meet contraction over that theory. The purpose of the present paper is to study the relationship more finely, by seeking an explicit map between the component orderings involved in each of the two kinds of contraction. It is shown that at least in the finite case a suitable map exists, with the consequence that the relational, transitively relational, and antisymmetrically relational partial meet contraction functions form identifiable subclasses of the safe contraction functions, over any theory finite modulo logical equivalence. In the process of constructing the map, as the composition of four simple transformations, mediating notions of bottom and top contraction are introduced. The study of the infinite case remains open. 相似文献
957.
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
958.
A number of models for categorical item response data have been proposed in recent years. The models appear to be quite different.
However, they may usefully be organized as members of only three distinct classes, within which the models are distinguished
only by assumptions and constraints on their parameters. “Difference models” are appropriate for ordered responses, “divide-by-total”
models may be used for either ordered or nominal responses, and “left-side added” models are used for multiple-choice responses
with guessing. The details of the taxonomy and the models are described in this paper.
The present study was supported in part by two postdoctoral fellowships awarded to Lynne Steinberg: an Educational Testing
Service Postdoctoral Fellowship at ETS, Princeton, NJ and an NIMH Individual National Research Service Award at Stanford University,
Stanford, CA. Helpful comments by the editor and three anonymous reviewers are gratefully acknowledged. 相似文献
959.
960.
Thomas A. Hulbert Charles L. Gdowski David Lachar 《Journal of abnormal child psychology》1986,14(1):115-122
Mothers' and fathers' responses on the Personality Inventory for Children (PIC) were compared for 360 clinic-referred children and adolescents. Interparent agreement was measured by several different indices. Correlations between parental pairs of scale T-scores derived from each parent averaged .66 for 13 of the profile scales; 9 of the scales exceeded this value. In contrast, mothers and fathers agreed in the classification of the presence of clinical significance an average of 77% of the time across these 13 scales, and pairs of parental PIC profiles contained an average of 3 scales in disagreement. The type of index used to measure interparent agreement was found to affect the results. The discussion examines the nature of interparent disagreement and addresses the implications regarding the use of fathers as informants on this instrument.This article is based on Thomas A. Hulbert's master's thesis. The authors extend their appreciation to James Orisell and Dena Mussaff for their assistance in data preparation and analysis. 相似文献