全文获取类型
收费全文 | 22504篇 |
免费 | 49篇 |
国内免费 | 1篇 |
专业分类
22554篇 |
出版年
2020年 | 25篇 |
2019年 | 46篇 |
2018年 | 3505篇 |
2017年 | 2849篇 |
2016年 | 2284篇 |
2015年 | 217篇 |
2014年 | 125篇 |
2013年 | 355篇 |
2012年 | 645篇 |
2011年 | 2458篇 |
2010年 | 2565篇 |
2009年 | 1518篇 |
2008年 | 1776篇 |
2007年 | 2229篇 |
2006年 | 69篇 |
2005年 | 282篇 |
2004年 | 214篇 |
2003年 | 163篇 |
2002年 | 110篇 |
2001年 | 56篇 |
2000年 | 90篇 |
1999年 | 46篇 |
1998年 | 44篇 |
1997年 | 37篇 |
1996年 | 25篇 |
1995年 | 18篇 |
1994年 | 24篇 |
1993年 | 19篇 |
1992年 | 28篇 |
1991年 | 23篇 |
1990年 | 28篇 |
1989年 | 31篇 |
1988年 | 29篇 |
1987年 | 22篇 |
1986年 | 27篇 |
1985年 | 30篇 |
1984年 | 27篇 |
1983年 | 22篇 |
1982年 | 18篇 |
1981年 | 23篇 |
1980年 | 25篇 |
1979年 | 38篇 |
1978年 | 21篇 |
1977年 | 25篇 |
1976年 | 17篇 |
1975年 | 16篇 |
1974年 | 22篇 |
1973年 | 24篇 |
1969年 | 18篇 |
1966年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
Erich Kirchler 《European journal of social psychology》1992,22(4):363-373
In the past, leadership was perceived to be the special province of males and still females tend not to occupy top management positions. Traditional social stereotypes hold that a leader needs to have typical masculine characteristics: he needs to be competitive, aggressive, tough and successful. Due to important changes in the conception of the societal female and male gender role during the last decades it can be assumed that the classical sex role stereotypes have at least become less polarized. Obituaries concerning deceased male and female managers, published in the years 1974, 1980 and 1986 in four daily newspapers were content analysed. Terms used to describe the managers were classified into 53 categories and included in a correspondence analysis. The results show that images of male and female managers were dissimilar in 1974 and 1980 and were still different in 1986. Male managers were perceived as intelligent, knowledgeable, experienced, outstanding instructors, unselfish opinion-leaders with an enviable entrepreneurial spirit. Women, on the other hand, were described as adorable, likeable superiors in 1974 and 1980. Some years later, in 1986, they became fighting managers: their surviving colleagues described them as courageous, highly committed workers who, nevertheless are still lacking in knowledge and expertise. 相似文献
22.
23.
Walter Schneider 《Behavior research methods》1989,21(2):334-340
A computer virus is a program that replicates itself and spreads to computers with the goal of disrupting or destroying normal computer use. In academic computing, viruses represent a serious problem that costs millions of dollars in losses annually and hinders the free exchange of information so critical to education. Viruses operate in incubation, infection, and destroy phases. The nature, mechanisms, and preventive measures for personal-computer viruses are reviewed. Different procedures are recommended to protect research laboratories, instructional laboratories, and software lending libraries. Tradeoffs between providing adequate protection and not having the security become too burdensome are considered. 相似文献
24.
John M. Eiler Walter W. Nelson Craig C. Jensen Steven P. Johnson 《Behavior research methods》1989,21(1):53-58
Using bar code technology to automate data collection provides a rapid and reliable alternative to paper-and-pencil tracking or keyboard entry into pocket or laptop computer. An array of bar code symbols is printed on a data menu, with a unique symbol corresponding to each possible observation. Bar code symbols are scanned using hand-held readers, which record the event, log the observation time, and store data for transfer to a personal computer. Advantages of the bar code monitoring system include: (1) ease of use by staff with minimal technical training, (2) reduced data entry errors and increased entry speed, (3) reliable portable operation, and (4) low-cost hardware. While the bar code system described here is used for behavioral monitoring in a residential treatment setting for the developmentally disabled, with minimal modification this system can be adapted for use in a wide variety of research and clinical applications. 相似文献
25.
26.
Hardyck, Tzeng, and Wang (1978, Brain and Language, 5, 56–71) hypothesized that ample repetition of a small number of stimuli is required in order to obtain VHF differences in tachistoscopic tasks. Four experiments, with varied levels of repetition, were conducted to test this hypothesis. Three experiments utilized the general task of object-picture naming and one utilized a word-naming task. Naming latencies constituted the dependent measure. The results demonstrate that for the object-naming paradigm repetition is required for RVF superiority to emerge. Repetition was found to be unnecessary for RVF superiority in the word-naming paradigm, with repetition actually reducing RVF superiority. Experiment I suggested the possibility that RVF superiority developed for the second half of the trials as a function of practice or hemispheric activation, regardless of repetition level. Subsequent experiments, better designed to assess this possibility, clearly refuted it. It was concluded that the effect of repetition depends on the processing requirements of the task. We propose that, for tasks which can be processed efficiently by one hemisphere, the effect of repetition will be to reduce VHF asymmetries; but tasks requiring substantial processing by both hemispheres will show shifts to RVF superiority as a function of repetition. 相似文献
27.
G von Collani 《Perceptual and motor skills》1985,61(2):523-531
On the basis of the hypothesis of misapplied constancy scaling, the perception of an abstract horizontal-vertical illusion figure embedded in photographs of natural scenes with depth cues is investigated. The effect is compared with that of a figure on photographs containing no depth information and with a figure on a neutral surface. It is shown that the magnitude of the illusion in the perspective scenes is greater than in the other two conditions. The results are considered compatible with a constancy theory of the illusion. Finally, the evidence for misapplied constancy scaling in the horizontal-vertical illusion in relation to a retinal theory is discussed. 相似文献
28.
The present experiments studied a three-event delayed sequence-discrimination (DSD) task: one arrangement (order) of two stimuli (red and yellow overhead lights) taken three in succession (e.g., red, yellow, red) was the positive sequence and the remaining seven arrangements were the negative sequences for responding and reward during the subsequent test stimulus. In Experiment 1, the final stimulus (recency) and the order of stimuli in the positive sequence controlled acquisition of discrimination. In Experiment 2, increasing the duration of memory intervals between stimuli reduced the discriminability of those negative sequences identical to the positive sequence after the delay. Three-event DSD performance in Experiments 1 and 2 was similar to two-event DSD performance in comparable published experiments. Models developed to explain pigeon performance in two-event DSD were extended to the three-event task. Results from both two- and three-event versions of the DSD task falsified a noncumulative model and several cumulative integration models (i.e., adding, averging, and some multiplying models), but corroborated one cumulative, multiplying model. 相似文献
29.
W von Suchodoletz V Airapetjanz W Gierow 《Psychiatrie, Neurologie, und medizinische Psychologie》1985,37(12):713-717
The cross-correlation method was used to measure interhemisphere phase differences over four areas of the brain in 22 healthy children aged between 7 and 10 years. Apart from defining normal values, the authors describe age-dependent characteristics and changes that take place as a result of mental stress. 相似文献
30.
Accuracy and laterality of ear preference in repeating 2, 3 and 4 word pairs (WP) of dichotic stimuli in English and French were determined in 80 right-handed subjects (anglophone/francophone, male/female), who were tested in both their native language (L1) and nonnative language (L2). Relative performance accuracy decreased as a function of word pairs per trial (from 2 to 4) as well as language (from L1 to L2). Right-lateral preference in turn increased as a function of WP (from 2 to 4) as well as language (L1 to L2). Right-ear advantage (REA) in L2 decreased as a function of language proficiency (low to high). REA was observed in over 90% of subjects. A rationale for greater lateralization of L2 performance is offered. 相似文献