全文获取类型
收费全文 | 11758篇 |
免费 | 254篇 |
国内免费 | 190篇 |
专业分类
12202篇 |
出版年
2015年 | 37篇 |
2013年 | 36篇 |
2012年 | 977篇 |
2011年 | 1154篇 |
2010年 | 278篇 |
2009年 | 134篇 |
2008年 | 924篇 |
2007年 | 918篇 |
2006年 | 811篇 |
2005年 | 723篇 |
2004年 | 616篇 |
2003年 | 611篇 |
2002年 | 542篇 |
2001年 | 350篇 |
2000年 | 502篇 |
1999年 | 214篇 |
1998年 | 74篇 |
1997年 | 51篇 |
1996年 | 73篇 |
1995年 | 40篇 |
1994年 | 77篇 |
1993年 | 116篇 |
1992年 | 99篇 |
1991年 | 105篇 |
1990年 | 96篇 |
1989年 | 99篇 |
1988年 | 114篇 |
1987年 | 127篇 |
1986年 | 89篇 |
1985年 | 120篇 |
1984年 | 121篇 |
1983年 | 139篇 |
1982年 | 95篇 |
1981年 | 92篇 |
1980年 | 79篇 |
1979年 | 87篇 |
1978年 | 75篇 |
1966年 | 48篇 |
1965年 | 133篇 |
1964年 | 105篇 |
1963年 | 126篇 |
1962年 | 54篇 |
1958年 | 145篇 |
1957年 | 116篇 |
1956年 | 89篇 |
1955年 | 58篇 |
1954年 | 49篇 |
1953年 | 54篇 |
1951年 | 41篇 |
1950年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
251.
252.
253.
1973年8月,南斯拉夫实践派的哲学家们,在科尔丘拉岛举行第十次夏季哲学问题讨论会。会议的总题目是:资本主义世界和社会主义。在这个标题下,大家也谈到了哲学的作用以及哲学和科学的关系。会上,G.彼得洛维奇就哲学的作用问题作了报告;接着,我也就这个论题发表了讲话。这篇讲话最初发表在1974年的《实践杂志》(第45页-52页)上。 相似文献
254.
我不想涉及过去对我的文章的各种反应的全部内容,只想就述评的某些地方做些简要的答复,这些地方我认为需要加以解释。 1.我一再特别强调:我所捍卫的按照从抽象上升到具体的方法来叙述辩证法的命题并不是我提 相似文献
255.
256.
257.
258.
By varying what we take to be the saliency oflandmarks (which are cues to location and orientation that are unique and visible from a distance), the slopes and intercepts of the time/angle function in the "mental rotation" task were caused to vary accordingly. 相似文献
259.
The effect of candy reward on I.Q. scores was investigated in 72 first- and second-grade children. All subjects were administered Form A of the Peabody Picture Vocabulary Test and, based upon these scores, were divided into three blocks: low, middle, and high. From each block, subjects were randomly assigned to one of three conditions (contingent reward, noncontingent reward, or no reward) that were in effect during administration of Form B. Results showed that candy given contingent upon each correct response increased I.Q. scores for the initially low scoring subjects, but had no influence on the scores of middle and high scoring subjects. 相似文献
260.
Effects of signals preceding and following shock on baseline responding during a conditioned-suppression procedure 总被引:1,自引:1,他引:0 下载免费PDF全文
Long-Evans rats were exposed to a succession of conditioned-suppression procedures involving pairings of (1) signal-shock, (2) shock-signal, and (3) a signal-shock-signal sequence in which first and second signals were at first physically identical. Traditional suppression of food-reinforced responding was obtained under the signal-shock arrangement, and exposure to the shock-signal sequence resulted in conditioned enhancement of responding during the signal. The signal-shock-signal condition reliably suppressed responding during the first signal, but produced no differential effect on response rate during the second signal. Baseline responding was least changed from preshock rates under the signal-shock-signal procedure, but baseline rate was considerably reduced under the signal-shock and shock-signal arrangements, the latter yielding most substantial reductions. A second experiment indicated that the magnitude and direction of changes in baseline responding reported in Experiment I were not confined to cases in which the first and second signals in the signal-shock-signal arrangement were physically identical. It is suggested that the major effects of the conditioned-suppression procedure on response rate might not be confined to presentations of the signal. 相似文献