全文获取类型
收费全文 | 33325篇 |
免费 | 1396篇 |
国内免费 | 15篇 |
出版年
2020年 | 370篇 |
2019年 | 394篇 |
2018年 | 622篇 |
2017年 | 597篇 |
2016年 | 631篇 |
2015年 | 432篇 |
2014年 | 595篇 |
2013年 | 2895篇 |
2012年 | 1019篇 |
2011年 | 1121篇 |
2010年 | 634篇 |
2009年 | 733篇 |
2008年 | 1029篇 |
2007年 | 981篇 |
2006年 | 938篇 |
2005年 | 875篇 |
2004年 | 860篇 |
2003年 | 836篇 |
2002年 | 825篇 |
2001年 | 1003篇 |
2000年 | 963篇 |
1999年 | 771篇 |
1998年 | 433篇 |
1997年 | 403篇 |
1996年 | 342篇 |
1995年 | 354篇 |
1994年 | 319篇 |
1993年 | 357篇 |
1992年 | 640篇 |
1991年 | 556篇 |
1990年 | 617篇 |
1989年 | 523篇 |
1988年 | 498篇 |
1987年 | 488篇 |
1986年 | 498篇 |
1985年 | 576篇 |
1984年 | 509篇 |
1983年 | 465篇 |
1982年 | 395篇 |
1981年 | 353篇 |
1979年 | 447篇 |
1978年 | 422篇 |
1977年 | 350篇 |
1976年 | 345篇 |
1975年 | 431篇 |
1974年 | 489篇 |
1973年 | 449篇 |
1972年 | 343篇 |
1968年 | 353篇 |
1966年 | 326篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
When some pictures are mirror reversed, aesthetic evaluations of them change dramatically. Stimulus features that may be important in contributing to this effect are: (a) location of areas of principal interest or weight in the picture space, (b) cues that suggest a direction of motion within the picture. Dextrals and inverted sinistrals preferred paintings with cues suggesting motion proceeding from left to right over their mirror-reversed versions and also preferred those with weight concentrated in the left portions of the picture space. The explanation that best fits these data is that preference is promoted when the picture content encourages attention to its rightmost portions, thus placing a majority of the picture in the left visual field where it is directly processed by the right hemisphere. 相似文献
22.
23.
John C. Bennett 《The Ecumenical review》1988,40(2):132-146
24.
25.
26.
27.
28.
29.
Susan D. Healy John R. Krebs 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1992,45(1):33-47
The ability of two species of tits to remember the location and/or features of an object was tested in a delayed-matching-to-sample procedure. Three values of retention interval between presentation of the sample stimulus and the choice--30 sec, 5 min, and 15 min--were used. Both species performed at above-chance level at all retention intervals, and there was no significant decline in accuracy with increasing interval. A pool of 100 stimulus objects was used, but the results of control trials indicated that the birds responded primarily to location rather than stimulus features of the object itseif. Although the food-storing marsh tit tended to perform at a higher level than the non-storing great tit, the only significant difference between the species was in the first 50 trials of the first treatment, when the birds were acquiring the task. The results are discussed in relation to the hypothesized special memory capacity of food-storing birds. 相似文献
30.
John M. Pearce Helen Kaye Louis Collins 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1985,37(4):379-396
Three experiments, each using a single group of pigeons, are reported. In Experiment 1 subjects were initially trained with two stimuli, one of which was always followed by food, the other being reinforced according to a 50% partial reinforcement schedule. Subsequently a serial procedure was adopted in which an additional stimulus, C, was consistently followed by the partially reinforced CS. A second additional stimulus, A, was followed on half of its occurrences by the continuously reinforced CS, its remaining presentations being followed by nothing. The rate of autoshaped keypecking was substantially greater during A than during C. In the remaining experiments subjects received first-order conditioning with a single stimulus that was either partially (Experiment 2) or continuously (Experiment 3) reinforced. The stimuli A and C were then again introduced for serial autoshaping. Stimulus A was occasionally paired with the CS and occasionally followed by nothing, whereas stimulus C was always followed by the CS. As in Experiment 1, the rate of responding during A was greater than during C. It is proposed that one influence on the rate of autoshaped keypecking during a CS is the accuracy with which the immediate consequences of that CS are predicted. 相似文献