全文获取类型
收费全文 | 19979篇 |
免费 | 876篇 |
国内免费 | 14篇 |
出版年
2021年 | 168篇 |
2020年 | 286篇 |
2019年 | 348篇 |
2018年 | 482篇 |
2017年 | 472篇 |
2016年 | 499篇 |
2015年 | 372篇 |
2014年 | 458篇 |
2013年 | 2061篇 |
2012年 | 818篇 |
2011年 | 877篇 |
2010年 | 526篇 |
2009年 | 553篇 |
2008年 | 726篇 |
2007年 | 716篇 |
2006年 | 728篇 |
2005年 | 634篇 |
2004年 | 596篇 |
2003年 | 613篇 |
2002年 | 615篇 |
2001年 | 451篇 |
2000年 | 419篇 |
1999年 | 393篇 |
1998年 | 257篇 |
1997年 | 261篇 |
1996年 | 240篇 |
1995年 | 201篇 |
1994年 | 192篇 |
1993年 | 207篇 |
1992年 | 257篇 |
1991年 | 269篇 |
1990年 | 238篇 |
1989年 | 218篇 |
1988年 | 179篇 |
1987年 | 206篇 |
1986年 | 225篇 |
1985年 | 270篇 |
1984年 | 253篇 |
1983年 | 210篇 |
1982年 | 185篇 |
1981年 | 200篇 |
1980年 | 181篇 |
1979年 | 219篇 |
1978年 | 177篇 |
1977年 | 159篇 |
1976年 | 167篇 |
1975年 | 170篇 |
1974年 | 208篇 |
1973年 | 176篇 |
1972年 | 130篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
51.
52.
V E Whiffen 《Journal of abnormal psychology》1988,97(4):467-474
53.
The influences of sex, age, and conversational, partner (mother vs. stranger) on eye contact during verbalizations were examined in a longitudinal study of 33 children at 2 and 4 years of age. A free-play sample was obtained of each child interacting with mother and with a male or female experimenter. The amount of eye contact in conjunction with verbalization was analyzed. Significant main effects were found for sex (females engaged in a higher percent of eye contact than males) and conversational partner (more eye contact while speaking exhibited to experimenter than to mother). There was an interaction between age and conversational partner, in that mother received more and experimenter relatively less percent of eye contact during verbalizations as children got older. Notably, there was no main effect for age. These results revealed sex differences at an age (2–2 1/2 years) and in a context (free-play setting) not previously studied, demonstrating the robustness of the effect. Further, age findings seem indicative of unique developmental trends for eye contact during verbalizations for the ages between 2 and 4 years.Mount Saint Vicent University 相似文献
54.
There is some controversy concerning whether or not the visual abilities of the newborn are mediated entirely through subcortical pathways or whether the visual cortex is functioning at birth. A critical test of cortical functioning is discrimination of orientation: orientation-selective neurons are found in the visual cortex but not in subcortical parts of the visual system. An experiment is described in which newborn infants were habituated to a square-wave grating oriented 45 degrees from vertical. After habituation, significant preferences for the novel, mirror-image, grating were found, a result which argues for some degree of visual cortical functioning at birth. 相似文献
55.
56.
V Di Lollo P Dixon 《Journal of experimental psychology. Human perception and performance》1988,14(4):671-681
Iconic memory, which was initially regarded as a unitary phenomenon, has since been subdivided into several components. In the present work we examined the joint effects of two such components (visible persistence and the visual analog representation) on performance in a partial report task. The display consisted of 15 alphabetic characters arranged around the perimeter of an imaginary circle on the face of an oscilloscope. The observer named the character singled out by a bar-probe. Two factors were varied: exposure duration of the array (10, 50, 100, 150, 200, 300, 400 or 500 ms) and duration of blank period (interstimulus interval, ISI) between the termination of the array and the onset of the probe (0, 50, 100, 150, or 200 ms). Performance was progressively impaired as both exposure duration and ISI were increased. The results were explained in terms of a probabilistic combinatorial model in which the timecourses of visible persistence and of the visual analog representation are regarded as time-locked to the onset and to the end of stimulation, respectively. The impairing effect of exposure duration was attributed to the relatively high spatial demands of the task that could be met optimally by information in visible persistence (which declines as a function of exposure duration), but less adequately by information in the visual analog representation. A second experiment, employing a task with lesser spatial demands, confirmed this interpretation. 相似文献
57.
We studied the effect of different postoperative times on the behavioral recovery following brain implants. Adult male rats received cortical tissue grafts 2 weeks after aspiration of the medial frontal cortex. Either 2 (Immediate Group) or 28 (Delay Group) days after grafting, the performance of these rats on a behavioral battery, comprising the Morris water maze task, forepaw use, and grooming, was compared to that of rats with similar lesions and postoperative recovery times but no grafts. Rats tested immediately after receiving implants performed better on the spatial navigation task than rats with similar lesions but no grafts. This improvement, however, was less than that shown by rats with lesions but no grafts permitted to recover for 28 days before testing. In contrast, in the Delay Group, rats with grafts were more greatly impaired than were their operated controls. Neither lesions nor grafts affected grooming although the Immediate Group with grafts were significantly more impaired in using their forepaws during feeding than were any of the other groups. These results lead us to conclude that differing postoperative recovery times and task requirements may account for some of the inconsistent results of the influence of brain grafts on behavioral recovery reported in the literature. We also conclude that cortical tissue implants can have two effects with different time courses and opposite net behavioral effects. 相似文献
58.
Previous theories of intrinsic motivation have traditionally ignored the experiential or subjective aspects of engagement in intrinsically and extrinsically motivated tasks. Part of the reason for the lack of research in this area was our ignorance of which emotions to study. Data are presented here from two studies designed to produce the first systematic evidence of changes in basic emotional states during task engagement. Our findings suggest that intrinsic and extrinsic tasks can be differentiated according to the emotional changes subjects retrospectively report about their engagement with these tasks, and point the way to future research incorporating emotion as an important variable to consider.The first author was supported in part by a Minority Fellowship administered by the American Psychological Association under a Clinical Training Grant from the National Institute of Mental Health (5 T01 MH13833), and by a Regents Fellowship from the University of California, Berkeley. 相似文献
59.
David Widerker 《Erkenntnis》1988,28(2):269-291
I would like to thank Eddy Zemach, Jonathan Stavi, Julius Moravcsik and Dov Gabbay for some very good discussions on the logical form of action sentences. Also, I am indebted to an anonymous referee of Erkenntnis for some very helpful comments on an earlier draft of this paper. 相似文献
60.
Jeffrey S. Levin Ph.D. M.P.H. C. David Jenkins Ph.D. Robert M. Rose M. D. 《Journal of religion and health》1988,27(4):267-278
In a study of air traffic controllers, religious differences are found in the way Type A behavior is associated with several health status indicators. Associations between the Jenkins Activity Survey (JAS) and physical illness incidence, health-promotive behavior, diastolic and systolic blood pressure, subjective distress and impulse control problems, and alcohol consumption are examined by religious attendance, religious affiliation, and change in affiliation. Findings confirm that Type A does not vary significantly by religion. However, there are several significant findings between Type A and various health indicators. Type A is associated with illness incidence, overall and more strongly in several religion, subgroups. Type A and alcohol consumption are related positively in Protestants and converts, and negatively in churchgoing Catholics. Type A is related to impulse control problems in churchgoing Protestants and to subjective distress in churchgoing Catholics. Finally, in individuals with weak or no religious ties, Type A is associated with lower blood pressure. This last finding suggests that in some people (for example, the irreligious or unchurched), the coronary-prone behavior pattern may have cardiovascular effects which are salutary in at least one respect.The authors wish to thank Dr. Kyriakos S. Markides and Laura A. Ray for their assistance with this study. Address requests for reprints to Dr. Levin at the Institute of Gerontology, 300 North Ingalls, Ann Arbor, MI 48109. 相似文献