全文获取类型
收费全文 | 130207篇 |
免费 | 5156篇 |
国内免费 | 52篇 |
出版年
2020年 | 1393篇 |
2019年 | 1725篇 |
2018年 | 2456篇 |
2017年 | 2584篇 |
2016年 | 2736篇 |
2015年 | 1944篇 |
2014年 | 2248篇 |
2013年 | 10426篇 |
2012年 | 4307篇 |
2011年 | 4389篇 |
2010年 | 2635篇 |
2009年 | 2674篇 |
2008年 | 3721篇 |
2007年 | 3764篇 |
2006年 | 3436篇 |
2005年 | 3998篇 |
2004年 | 3349篇 |
2003年 | 3025篇 |
2002年 | 2847篇 |
2001年 | 3900篇 |
2000年 | 3710篇 |
1999年 | 2854篇 |
1998年 | 1458篇 |
1997年 | 1304篇 |
1996年 | 1325篇 |
1995年 | 1226篇 |
1993年 | 1204篇 |
1992年 | 2431篇 |
1991年 | 2261篇 |
1990年 | 2302篇 |
1989年 | 2092篇 |
1988年 | 2082篇 |
1987年 | 1989篇 |
1986年 | 2022篇 |
1985年 | 2042篇 |
1984年 | 1794篇 |
1983年 | 1608篇 |
1982年 | 1192篇 |
1979年 | 1889篇 |
1978年 | 1378篇 |
1975年 | 1517篇 |
1974年 | 1696篇 |
1973年 | 1830篇 |
1972年 | 1499篇 |
1971年 | 1399篇 |
1970年 | 1252篇 |
1969年 | 1306篇 |
1968年 | 1618篇 |
1967年 | 1466篇 |
1966年 | 1284篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
M Tomonaga T Matsuzawa 《Journal of comparative psychology (Washington, D.C. : 1983)》1992,106(1):43-52
In a conditional-discrimination task (matching-to-sample), we assessed similarities among figures consisting of 2 elemental figures through the choice reaction time, nonmetric multidimensional scaling, and hierarchical cluster analysis data from chimpanzees (Pan troglodytes) and humans (Homo sapiens). Humans also rated similarities among figures. The results of the 3 experiments clearly indicated that the reaction time data obtained from chimpanzees' performances were useful measures of the similarities among figures. The results suggested that chimpanzees and humans perceived the complex figures similarly. The outer-contour elements were perceived most dominantly by both species, and the straight-line elements were perceived least dominantly. Both species showed the same perceptual hierarchy or dominance among perceptual categories, as determined by the similarity of simple elements, on the basis of transformational invariances. 相似文献
992.
J D Batson J S Hoban M E Bitterman 《Journal of comparative psychology (Washington, D.C. : 1983)》1992,106(2):114-119
Honeybees (Apis mellifera) were classically conditioned with odor as conditioned stimulus (CS), sucrose as unconditioned stimulus (US), and proboscis extension as response. The purpose of Experiment 1 (Ns = 26 and 27) was to look for facilitation of forward conditioning by CS-US overlap, but rapid conditioning without overlap left little room for improvement. In 2 further experiments, CS and US were simultaneous, and response to odor alone was measured in subsequent tests. In Experiment 2, a Simultaneous group (N = 25) responded more to the training odor than did an Unpaired control group (N = 25). In Experiment 3, a differentially conditioned Simultaneous group (N = 29) responded more to an odor paired with sucrose in training (S+) than to an odor presented alone (S-). The implications of the results for the problem of the role of amount of reward in honeybee learning are considered. 相似文献
993.
Much of the methodology in stress research focuses on stress manifestation and organismic reactions to life’s crises. In contrast,
the present study sought to identify the major sources of stress and the nature of those sources. The results revealed a consistent
pattern in high and low stressors throughout the 3-year period of the study, and differences only of intensity between males
and females, not type of stress. Except for individuals’ temporal variations in critical events, the highest stressors for
the groups were external, primarily financial and time management. Internal sources, such as personal relationships and self-absorption,
were typically the lowest concerns. Everyday problems arising from current life styles seem to be significant sources of stress. 相似文献
994.
I examined preweanling rats' (Rattus norvegicus) expression of ultrasounds and secretion of ACTH when exposed to unfamiliar adult male rats or to their mothers. Pups at 7 days of age produced similar levels of ultrasonic vocalization near both unfamiliar males and mothers. However, these pups could discriminate familiar from unfamiliar adults because ACTH was significantly higher in pups near adult males than in those near mothers. At 14 days of age, pups avoided adult males but not their mothers; therefore, adult males represented a significant threat. Importantly, 14-day-old rats significantly reduced ultrasound production only when near adult males. Pups at 21 days of age no longer emitted ultrasounds when socially isolated or when near conspecific adults. In addition, 14- and 21-day-old rats produced similar elevated ACTH levels across stimulus conditions. Results show significant changes in preweanling rats' responses to conspecific adults. 相似文献
995.
996.
Two experiments are reported which investigated how subject gender and time-of-day influenced the estimation of duration and
the perception of task-related mental workload. In the first experiment, 24 subjects performed a filled time-estimation task
in a constant blacked-out, noise-reduced environment at 0800h, 1200h, 1600h, and 2000h, respectively. In the second experiment,
12 different subjects performed an unfilled time estimation task in similar conditions at 0900h, 1400h, and 1900h. At the
termination of all experimental sessions, participants completed the NASA Task Load Index workload assessment questionnaire
as a measure of perceived mental workload. Results indicated that physiological response, reflected in body temperature change,
followed an expected pattern of sequential increase with time-of-day. However, estimates of duration and the perception of
mental workload showed no significant effects for time-of-day. In each of the experiments there were significant differences
in time estimation and mental workload response contingent on the gender of the participant. These results are interpreted
in light of the previous positive findings for circadian fluctuation in performance efficiency and the equivocal findings
of a gender difference in time estimation. A unifying account of these collective results is given based on gender by time-of-day
interactional effects.
An earlier version of this paper was presented at the 32nd Annual Meeting of the Human Factors Society, Anaheim, CA, October,
1988. 相似文献
997.
M. S. Singer 《Current Psychology》1992,11(2):128-144
This study attempted to apply the relative deprivation theory to preferential selection research. Two questions were addressed
in this context: First, does preferential selection cause feelings of injustice or deprivation? and, second, can the magnitude
of such feelings of injustice be predicted? A questionnaire was designed to assess fairness perceptions of all types of selection
outcomes: preferential selection; together with selection involving discrimination against minorities and selections without
either forms of discrimination. Results showed that preferential selection caused feelings of injustice. The level of felt
injustice associated with preferential selection was identical to that due to discrimination against minorities. Further,
the magnitude of felt injustice due to preferential selection could be predicted by the size of the discrepancy in “performance-relevant
merits” between the selected minority candidate and the unsuccessful majority candidate. The study also compared effects of
the “self-other” comparison process, used in previous relative deprivation research, and a “other-other” comparison process
on justice perception. Implications of the results for the application of relative deprivation theory to preferential selection
research were discussed. 相似文献
998.
Psychological knowledge from eye-witness research is applied here to the particular problem of reporting road accidents. Thereby
the paper highlights some of the assumptions in eye-witness research. The interface between that research and the reporting
of road accidents is examined by reference to existing social psychological notions. These are notions about questioning and
about hypothesis testing. The paper makes special reference to the questioning of child witnesses because problems therein
are particularly acute. 相似文献
999.
Measures of spatial cognition, neighborhood knowledge, and neighborhood use from the research described by Walsh, Krauss, and Regnier (1981) were examined to determine if laboratory tests of spatial cognition were significant predictors of older adults' use of their neighborhoods. The overall results show that laboratory-based measures of spatial cognition and subjects' knowledge of their neighborhoods are both significant predictors of their use of neighborhood goods and services. The ability to learn and remember the location and orientation of objects, when contextual cues were not provided at test, was more predictive of the participants' neighborhood use than either the participants' number of years in the neighborhood or their mobility. Spatial memory as measured by the Educational Testing Service Building Memory task predicted neighborhood knowledge, which was predictive of neighborhood use. 相似文献
1000.
Elders exposed to either progressive or imaginal relaxation procedures reported significant relaxation effects and showed improvement on measures of personal functioning. The results of the Physical Assessment Scale of the Relaxation Inventory indicated that relaxation responses were acquired within and across sessions. Large, consistent changes in relaxation occurred in all 4 sessions. The Symptom Checklist-90-R, which measures self-reported personal adjustment, showed significant positive changes following relaxation training and at 1-month follow-up. Elders who imagined muscle tension release profited as much as those engaged in actual muscle tension-release activities. This finding is of importance for older adults who may experience physical limitations that contraindicate muscle-tension-release procedures. 相似文献