全文获取类型
收费全文 | 2235篇 |
免费 | 116篇 |
出版年
2023年 | 23篇 |
2022年 | 17篇 |
2021年 | 29篇 |
2020年 | 43篇 |
2019年 | 43篇 |
2018年 | 73篇 |
2017年 | 69篇 |
2016年 | 87篇 |
2015年 | 81篇 |
2014年 | 66篇 |
2013年 | 267篇 |
2012年 | 111篇 |
2011年 | 134篇 |
2010年 | 76篇 |
2009年 | 80篇 |
2008年 | 94篇 |
2007年 | 93篇 |
2006年 | 77篇 |
2005年 | 82篇 |
2004年 | 81篇 |
2003年 | 78篇 |
2002年 | 82篇 |
2001年 | 38篇 |
2000年 | 28篇 |
1999年 | 27篇 |
1998年 | 29篇 |
1997年 | 21篇 |
1996年 | 25篇 |
1995年 | 25篇 |
1994年 | 19篇 |
1993年 | 21篇 |
1992年 | 18篇 |
1991年 | 18篇 |
1990年 | 14篇 |
1989年 | 23篇 |
1988年 | 15篇 |
1987年 | 10篇 |
1986年 | 12篇 |
1985年 | 15篇 |
1984年 | 17篇 |
1983年 | 21篇 |
1982年 | 12篇 |
1981年 | 15篇 |
1980年 | 19篇 |
1979年 | 17篇 |
1978年 | 19篇 |
1977年 | 13篇 |
1975年 | 15篇 |
1974年 | 15篇 |
1973年 | 8篇 |
排序方式: 共有2351条查询结果,搜索用时 250 毫秒
21.
22.
Three rhesus monkeys were trained to press either of two response keys. A response on the reinforcement key during presentation of the reinforced stimulus produced a sucrose pellet followed by an intertrial interval, but during presentation of the unreinforced stimulus produced only the intertrial interval. A response on the switching key changed the discriminative stimulus from reinforced to unreinforced or from unreinforced to reinforced. The reinforced stimulus was presented automatically on half the trials, but could be produced only by a switching response on the other half. Switching tended to occur in three distinct stages during acquisition of discriminative behavior. The first stage was identified as "nondiscriminative switching"; the second as "nonswitching"; and the third as "discriminative switching". 相似文献
23.
24.
Michael D. Gliksman M.P.H. F.A.C.O.M. Allan Kellehear Ph.D. 《Journal of Near-Death Studies》1990,9(1):41-43
Although cerebral anoxia is not thought to be responsible for triggering near-death experiences (NDEs), the issue is not so clear in the case of hypercapnia. Detection of normal blood gases in Michael Sabom's (1982) case study seems to be the major reply to suggestions that hypercapnia may have a causal role in NDEs. We argue, however, that routine arterial measures of blood gases are not a reliable indicator of cerebral levels. 相似文献
25.
Carol A. Fowler Catherine T. Best Gerald W. Mcroberts 《Attention, perception & psychophysics》1990,48(6):559-570
Phonetic segments are coarticulated in speech. Accordingly, the articulatory and acoustic properties of the speech signal during the time frame traditionally identified with a given phoneme are highly context-sensitive. For example, due to carryover coarticulation, the front tongue-tip position for HI results in more fronted tongue-body contact for a /g/ preceded by /l/ than for a /g/ preceded by /r/. Perception by mature listeners shows a complementary sensitivity—when a synthetic /da/-/ga/ continuum is preceded by either /al/ or /ar/, adults hear more /g/s following HI rather than Irl. That is, some of the fronting information in the temporal domain of the stop is perceptually attributed to /l/ (Mann, 1980). We replicated this finding and extended it to a signaldetection test of discrimination with adults, using triads of disyllables. Three equidistant items from a /da/-/ga/ continuum were used preceded by /al/ and /ar/. In the identification test, adults had identified item ga5 as “ga”, and dal as “da”, following both /al/ and /ar/, whereas they identified the crucial item d/ga3 predominantly as “ga” after /al/ but as “da” after /ar/. In the discrimination test, they discriminated d/ga3 from dal preceded by /al/ but not /ar/; compatibly, they discriminated d/ga3 readily from ga5 preceded by /ar/ but poorly preceded by /al/. We obtained similar results with 4-month-old infants. Following habituation to either ald/ga3 or ard/ga3, infants heard either the corresponding ga5 or dal disyllable. As predicted, the infants discrimi-nated d/ga3 from dal following /al/ but not /ar/; conversely, they discriminated d/ga3 from ga5 following /ar/ but not /al/. The results suggest that prelinguistic infants disentangle consonant-consonant coarticulatory influences in speech in an adult-like fashion. 相似文献
26.
Catherine Kirchmeyer 《Sex roles》1993,28(9-10):531-552
A more balanced view of nonwork-to-work spillover was advanced here. The concentration of research on the negative side may serve to support some damaging assumptions about professional women. A sample of 221 experienced managers indicated how parenting, community work, and recreation affected work both positively and negatively, and the extent they used certain coping strategies. Women comprised 35% of the sample and ethnic minorities comprised 18%. The managers agreed more strongly with statements about positive nonwork-to-work spillover than with those about the negative side. Women and men reported largely the same levels of nonwork involvement, time commitment, satisfaction, positive spillover, and use of the coping strategies. Compared to men, women did report lower negative spillover overall, and greater use of the strategies when they were parents. The findings suggest that employers should be less concerned with how active women are in nonwork, and more concerned with how well both men and women manage their various life domains. 相似文献
27.
On the basis of a conditioning analysis of the orientation-contingent color aftereffect (McCollough effect, ME), orientation stimuli become associated with simultaneously presented chromatic stimuli. This account suggests that decreasing the contingency between the grid orientation and color should decrease the strength of the aftereffect. Results of previous research indicate that decreasing the temporal contingency (by presenting homogeneous chromatic stimuli between presentations of chromatic grids) does not decrease the ME. However, it has been suggested that the appropriate contingency-degradation procedure would involve decreasing spatial (rather than temporal) contingency. That is, the illusion should be attenuated by extending the color beyond the confines of the grid. Contrary to this hypothesis, the results of the present experiments provide no evidence that decreasing the spatial contingency between grid and color decreases the ME; rather, the aftereffect is increased by such a manipulation. 相似文献
28.
29.
A central contention of much of the literature about the nature of work values and the meaning of work is that there is (or at least has been) a consensual work ethic operating in modern industrial societies. This premise has surprisingly, rarely been put to the test. In this paper, evidence for a modern work ethic is obtained from the European Values Survey. The link between this work ethic and religion is then explored. While one conclusion of the analysis is that it is still an identifiably Protestant ethic, contextual analysis demonstrates that the effect of a country's religious culture is more potent than the religious beliefs of the individual. 相似文献
30.