全文获取类型
收费全文 | 1431篇 |
免费 | 45篇 |
专业分类
1476篇 |
出版年
2021年 | 27篇 |
2020年 | 14篇 |
2019年 | 24篇 |
2018年 | 30篇 |
2017年 | 30篇 |
2016年 | 38篇 |
2015年 | 21篇 |
2014年 | 30篇 |
2013年 | 158篇 |
2012年 | 47篇 |
2011年 | 83篇 |
2010年 | 31篇 |
2009年 | 30篇 |
2008年 | 48篇 |
2007年 | 49篇 |
2006年 | 33篇 |
2005年 | 39篇 |
2004年 | 57篇 |
2003年 | 39篇 |
2002年 | 28篇 |
2001年 | 28篇 |
2000年 | 23篇 |
1999年 | 18篇 |
1998年 | 25篇 |
1997年 | 16篇 |
1996年 | 20篇 |
1995年 | 22篇 |
1994年 | 21篇 |
1993年 | 14篇 |
1992年 | 23篇 |
1991年 | 15篇 |
1990年 | 19篇 |
1989年 | 14篇 |
1988年 | 21篇 |
1987年 | 17篇 |
1985年 | 14篇 |
1984年 | 16篇 |
1983年 | 23篇 |
1982年 | 11篇 |
1981年 | 14篇 |
1980年 | 14篇 |
1979年 | 18篇 |
1978年 | 14篇 |
1977年 | 14篇 |
1976年 | 13篇 |
1975年 | 13篇 |
1974年 | 15篇 |
1973年 | 12篇 |
1967年 | 12篇 |
1950年 | 13篇 |
排序方式: 共有1476条查询结果,搜索用时 15 毫秒
231.
New Caledonian crows are the most proficient non-hominin tool manufacturers but the cognition behind their remarkable skills
remains largely unknown. Here we investigate if they attend to the functional properties of the tools that they routinely
use in the wild. Pandanus tools have natural barbs along one edge that enable them to function as hooking implements when
the barbs face backwards from the working tip. In experiment 1 we presented eight crows with either a non-functional (‘upside-down’)
or a functional pandanus tool in a baited hole. Four of the crows never flipped the tools. The behaviour of the four flipping
birds suggested that they had a strategy of flipping a tool when it was not working. Observations of two of the eight crows
picking up pandanus tools at feeding tables in the wild supported the lack of attention to barb direction. In experiment 2
we gave six of the eight crows a choice of either a barbed or a barbless pandanus tool. Five of the crows chose tools at random,
which further supported the findings in experiment 1 that the crows paid little or no attention to the barbs. In contrast,
a third experiment found that seven out of eight crows flipped non-functional stick tools significantly more than functional
ones. Our findings indicate that the crows do not consistently attend to the presence or orientation of barbs on pandanus
tools. Successful pandanus tool use in the wild seems to rely on behavioural strategies formed through associative learning,
including procedural knowledge about the sequence of operations required to make a successful pandanus tool.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
232.
Andrew M. Burck John M. Laux Martin Ritchie David Baker 《Journal of Addictions & Offender Counseling》2008,29(1):49-61
In this study, the authors examined the Substance Abuse Subtle Screening Inventory‐3 Correctional scale's sensitivity and specificity at detecting college students' illegal behaviors. Sensitivity was strong, but specificity was weak. Implications for counseling and suggestions for future research are included. 相似文献
233.
Daniel C. Russell 《The Southern journal of philosophy》2008,46(2):299-315
Virtue ethicists sometimes say that a right action is what a virtuous person would do, characteristically, in the circumstances. But some have objected recently that right action cannot be defined as what a virtuous person would do in the circumstances because there are circumstances in which a right action is possible but in which no virtuous person would be found. This objection moves from the premise that a given person ought to do an action that no virtuous person would do, to the conclusion that the action is a right action. I demon‐strate that virtue ethicists distinguish “ought” from “right” and reject the assumption that “ought” implies “right.” I then show how their rejection of that assumption blocks this “right but not virtuous” objection. I conclude by showing how the thesis that “ought” does not imply “right” can clarify a further dispute in virtue ethics regarding whether “ought” implies “can.” 相似文献
234.
Clark RD 《Perceptual and motor skills》2008,107(1):222-224
This study investigated whether the slight advantage of higher seeded players to win in match play on the men's Professional Golfers' Association Tour generalizes to the Ladies Professional Golf Association Tour. Analysis showed no significant advantage for the higher seeded player in match play. The highly restricted range of skill of tour players makes it mainly a matter of chance who will win any match-play event or who will have the better or worse scores on any given day. 相似文献
235.
Russell T. McCutcheon Aaron T. Hollander Andrew F. Durdin Kelli A. Gardner Adam T. Miller Emily D. Crews 《Teaching Theology & Religion》2016,19(1):78-98
This series of short essays considers the complex choices and decision‐making processes of instructors preparing to teach, and continuing to teach, introductory courses in religious studies. In a paper originally presented in the University of Chicago's “The Craft of Teaching in the Academic Study of Religion” series, Russell McCutcheon explores a “baker's dozen” of such choices and the larger pedagogical problems with which they are entwined, ranging from classic questions of skill development and content coverage to philosophical concerns around students' identification with their topics of study and institutional concerns around governance and assessment. Aaron Hollander provides a brief introduction and four doctoral students at the University of Chicago Divinity School respond to McCutcheon's essay, widening its scope, testing its applicability, and interrogating its undergirding suppositions from the perspective of early‐career educators in the field. 相似文献
236.
237.
This study examines the extent to which perceptions of partner violence are influenced by aggressor gender and masculinity/femininity, and victim gender. Participants evaluated a case scenario depicting domestic assault. Results found charges were significantly higher and sentences significantly longer when the victim was female. Masculine aggressors were more likely to be perceived as having threatened bodily injury and as having initiated the assault compared to feminine aggressors. Masculine aggressors in heterosexual relationships were more likely to be identified as having initiated an assault compared to feminine aggressors in heterosexual relationships or individuals in same-sex relationships. 相似文献
238.
Jeffrey Sanford Russell 《Inquiry (Oslo, Norway)》2016,59(3):239-263
Some hold that the lesson of Russell’s paradox and its relatives is that mathematical reality does not form a ‘definite totality’ but rather is ‘indefinitely extensible’. There can always be more sets than there ever are. I argue that certain contact puzzles are analogous to Russell’s paradox this way: they similarly motivate a vision of physical reality as iteratively generated. In this picture, the divisions of the continuum into smaller parts are ‘potential’ rather than ‘actual’. Besides the intrinsic interest of this metaphysical picture, it has important consequences for the debate over absolute generality. It is often thought that ‘indefinite extensibility’ arguments at best make trouble for mathematical platonists; but the contact arguments show that nominalists face the same kind of difficulty, if they recognize even the metaphysical possibility of the picture I sketch. 相似文献
239.
Yu H Russell DM Sternad D 《Journal of experimental psychology. Human perception and performance》2003,29(3):616-630
Variability in rhythmic movements has been interpreted as a signature of internal or peripheral noise processes. Grounded in an oscillator interpretation, this study hypothesized that period variability and drift arises from the asymmetry between target period and the limb's intrinsic dynamics. Participants synchronized to 7 target periods, swinging 1 of 3 pendulums in a continuation paradigm; 3 periods were longer, 3 shorter, and 1 identical to the preferred period. Results supported 5 predictions: Drift toward the preferred period was observed that scaled with the asymmetry. Variability was lowest for symmetry conditions and increased with the asymmetry. Variability decreased concomitant with the approach toward the preferred period. Periods exponentially approached the preferred period with positive autocorrelations up to 10 cycles. 相似文献
240.
Spears R Gordijn E Dijksterhuis A Stapel DA 《Personality & social psychology bulletin》2004,30(5):605-616
Whereas previous research has shown automatic behavior conforming to outgroup stereotypes, the authors demonstrate automatic behavioral contrast away from a stereotype/trait associated with an outgroup (Study 1 and 2) and point to the importance of an "us-them" intergroup comparison in this process. In Study 1, participants colored pictures more messily when neatness was associated with an outgroup rather than the ingroup. In Study 2, using a different behavior, participants primed with busy business people reacted faster than controls (assimilation) but became slower when their student ingroup identity was activated (contrast). Subliminally priming an "us-them" intergroup comparison set undermined the accessibility of outgroup stereotypic words (Study 3), especially for those higher in prejudice (Study 4). This suggests that people automatically distance themselves from outgroup attributes when intergroup antagonism is cued or chronic. Implications for the role of self and comparison processes in automatic behavior are discussed. 相似文献