全文获取类型
收费全文 | 4565篇 |
免费 | 136篇 |
国内免费 | 3篇 |
出版年
2022年 | 44篇 |
2021年 | 59篇 |
2020年 | 91篇 |
2019年 | 90篇 |
2018年 | 164篇 |
2017年 | 142篇 |
2016年 | 143篇 |
2015年 | 78篇 |
2014年 | 91篇 |
2013年 | 366篇 |
2012年 | 157篇 |
2011年 | 133篇 |
2010年 | 95篇 |
2009年 | 114篇 |
2008年 | 125篇 |
2007年 | 123篇 |
2006年 | 100篇 |
2005年 | 94篇 |
2004年 | 83篇 |
2003年 | 66篇 |
2002年 | 59篇 |
2001年 | 138篇 |
2000年 | 99篇 |
1999年 | 80篇 |
1996年 | 40篇 |
1993年 | 50篇 |
1992年 | 64篇 |
1991年 | 71篇 |
1990年 | 59篇 |
1989年 | 57篇 |
1988年 | 64篇 |
1987年 | 59篇 |
1986年 | 52篇 |
1985年 | 62篇 |
1984年 | 60篇 |
1983年 | 47篇 |
1982年 | 53篇 |
1981年 | 40篇 |
1979年 | 61篇 |
1978年 | 59篇 |
1977年 | 54篇 |
1976年 | 48篇 |
1975年 | 65篇 |
1974年 | 61篇 |
1973年 | 58篇 |
1972年 | 52篇 |
1971年 | 53篇 |
1968年 | 49篇 |
1967年 | 61篇 |
1966年 | 43篇 |
排序方式: 共有4704条查询结果,搜索用时 15 毫秒
151.
The purpose of the study is to investigate the influence of initial projection of the centre of gravity (CG) on the spatial and temporal organization of the dynamic phenomena accompanying a voluntary movement in humans. From a horizontal quadrupedal stance, ten normal subjects were instructed to raise the right forelimb towards a support target in self paced velocity conditions. Three experimental conditions were tested for which the initial CG projection was either within (C1), at the limits of (C2) or outside the supporting triangle (C3). The results showed that vertical force variations on the four supports always preceded the first vertical displacement of the right wrist (onset of the movement). From C1 to C3, the duration of these anticipatory dynamic phenomena increased enabling an adjustment of the CG position such that equilibrium constraints were fulfilled. For all conditions, the acceleration peak of the CG occurred prior to the onset of movement and from C1 to C3, its magnitude increased in a single direction of the horizontal plane. For each condition, the load transfer was directed to the left forelimb and the right hindlimb (diagonal strategy) and reached a maximal value at the time of lift-off. With respect to this moment, the onset of the movement occurred increasingly early from C1 to C3. These results suggest that contribution of peripheral cues to postural control is more important, when the requirements of horizontal CG displacement increase. 相似文献
152.
Lindsley OR 《The Behavior analyst / MABA》1996,19(2):211-224
This article briefly reviews behavioral fluency and its 10 products. Fluency development requires three of the four free-operant freedoms: the freedom to present stimuli at the learner's rhythm, the freedom to form the response, and the freedom to speed at the learner's maximum frequency. The article closes with several suggestions that fluent performing is really operant response-response (R-R) chaining, and recommends further controlled laboratory research on free-operant R-R chaining. 相似文献
153.
Scott O. Lilienfeld Tanya Hess Cherilyn Rowland 《Journal of psychopathology and behavioral assessment》1996,18(3):285-303
A number of authors have proposed that psychopathic individuals possess an abnormally constricted time horizon (i.e., foreshortened sense of the future). This hypothesis was tested among 101 undergraduates, who were administered a battery of (1) self-report indices of psychopathic personality traits, antisocial behavior, and normal-range personality traits; (2) self-report indices of time perspective; (3) projective tests of time perspective; and (4) laboratory tasks assessing time estimation and capacity for foresight and impulse control. Measures of psychopathy/antisocial behavior tended to be negatively correlated with several self-report indices assessing preoccupation with the future and with a projective task assessing the frequency of thoughts concerning future events, although only one of the correlations with this latter task was significant. In most cases these correlations were not attributable to the variance shared by measures of psychopathy/antisocial behavior and measures of (low) anxiety-proneness, although several correlations decreased substantially after levels of harmavoidance were controlled. In contrast, measures of psychopathy/antisocial behavior were negligibly correlated with laboratory tasks. These results provide mixed support for the short time horizon hypothesis and suggest that further attention to the role of method factors in investigations of future time perspective is warranted. 相似文献
154.
155.
Little MO 《Kennedy Institute of Ethics journal》1996,6(1):1-18
Many have asked how and why feminist theory makes a distinctive contribution to bioethics. In this essay, I outline two ways in which feminist reflection can enrich bioethical studies. First, feminist theory may expose certain themes of androcentric reasoning that can affect, in sometimes crude but often subtle ways, the substantive analysis of topics in bioethics; second, it can unearth the gendered nature of certain basic philosohical concepts that form the working tools of ethical theory. 相似文献
156.
Rev’d Ian StJohn Fisher Ph.D. 《Science and engineering ethics》1996,2(3):335-344
Religion, defined as ‘the idea of a state that transcends ourselves and our world and the working out of the consequences
of that idea’, may influence the ethical thinking of scientists and engineers in two ways. The first is at the level of the
individual and how personal beliefs affect the choice of research, design or development projects, relationships with other
researchers and the understandings of the consequences of research on other aspects of life. The second level is that of the
social and cultural setting in which scientists and engineers work; how society decides which research to sponsor, how to
apply the results of scientific discovery and which technology it chooses to develop and for what purposes. In neither of
these areas is religious belief a necessary condition for scientists and engineers to pursue one course of action rather than
another. The existence of religious belief within the individual and society is, though, part of the ethical framework in
which scientist and engineers work and therefore something to which attention should be paid. Religion provides a particular
perspective on what should be. Conversely science and technology provide information on the nature of the person and the universe
in which we live, which must be taken into account when theologians and religious moralists apply their ethical norms and
principles. 相似文献
157.
158.
159.
160.