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971.
Sequences of nine binary auditory signals (dots and dashes) were presented to 20 subjects in Experiment I. The subjects were instructed to internally organize the signals into two-dimensional arrays. Visual patterns (letters) could be recognized in these imaginary arrays in both upright and rotated orientations. In Experiment II, a group of nine subjects, which was instructed to use spatial imagery of this kind, reproduced significantly longer sequences of signals than nine control subjects. By means of internal spatial organization, experimental subjects were able to reproduce sequences up to 45 signals in length, whereas control subjects recalled near the chance level for portions of sequences longer than nine signals. Three levels of information processing were postulated to account for the results, with spatial organization occupying a mediating level between acoustic and verbal levels. 相似文献
972.
Three rats were trained on a schedule in which a response on lever B was reinforced only if it was preceded by a minimum number of consecutive responses on lever A. The minimum requirement was 27 A responses for Rat 1, and 20 A responses for Rats 2 and 3. The schedule maintained high rates of responding on lever A, and a slow, spaced pattern of responding on lever B. The mean number of consecutive responses on lever A was slightly greater than the minimum required. The effect of superimposing on this behavior a stimulus that ended with an unavoidable shock was the suppression of responding on both levers during the pre-shock stimulus. Responses on lever A were more suppressed, and the proportion of relatively short response runs on lever A during the pre-shock stimulus increased. With all three rats, the mean number of consecutive responses on lever A during the pre-shock stimulus decreased to a value below the minimum requirement for reinforcement of the subsequent B response. 相似文献
973.
974.
Choice of higher density signalled shock over lower density unsignalled shock 总被引:3,自引:3,他引:0
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Unsignalled, inescapable shocks were presented to four albino rats in Experiment 1. By pressing a lever subjects could change the condition to signalled shock for 3-min periods after which unsignalled shock was automatically reinstated. All subjects changed from unsignalled to signalled shock when shock density was the same or when the density of signalled shock was two times greater than unsignalled shock. When the density of signalled shock was four times that of unsignalled shock, three subjects changed to the higher density schedule. One subject changed to a density of signalled shock eight times that of unsignalled shock. The second study showed that the two shock schedules most similar in Experiment 1 were discriminably different because subjects chose lower over higher shock densities when both densities were unsignalled. An analysis stressing safe (signal absent) and unsafe (signal present) periods was discussed. 相似文献
975.
Lewis P Lewin L Muehleisen P Stoyak M 《Journal of the experimental analysis of behavior》1974,22(1):143-150
Key pecking was reinforced on a two-component multiple schedule. A variable-interval schedule controlled reinforcement in both components. During one component, access to reinforcement was preceded by a tone; in the other component, a standard unsignalled schedule was in effect. After performance stabilized, subjects were given a choice between the signalled and unsignalled schedules. They were placed in the chamber with the unsignalled schedule in effect on the right key. A single response on the left, or changeover, key produced the signalled schedule for 1 min. Both pigeons in Experiment I pecked the changeover key at a rate sufficient to remain under the signalled schedule for over 90% of the session. Removing and reintroducing the tone demonstrated that the changeover-key responses were due to the occurrence of the tone. In Experiment II, when pecking the changeover key produced the unsignalled schedule, pecking the changeover key declined. The results may be explained either in terms of Hendry's information hypothesis or as escape from an intermittent positive reinforcement schedule. 相似文献
976.
在普列汉诺夫的遗著中,关于哲学史问题的著作和言论有着重大的意义。在哲学史方面普列汉诺夫所感到兴趣的问题是非常广泛的;它包括人类思想史的一个巨大领域——从原始社会万物有灵观念的发生直到二十世纪的各种资产阶级哲学学说(新康德主义、马赫主义、实用主义、克罗齐主义、马萨列克主义以及其它等等)。普列汉诺夫还研究了各种各样的社会思潮——从亚里士多德的观点直到帝国主义资产阶级的社会学“理论”(施塔莫勒、司徒卢威以及其他等等)。 相似文献
977.
让我们看一看哈维(Havet)先生所讲的最重要趋势的结果怎样,首先看他所谓“柏格森的精神实在论”的结果怎样。虽然这种哲学对于心灵解放有很大的贡献,但我们也应该考虑到它对于一些重大问题已经下了明确的结论,而这些结论是一个希望被称做柏格森学派的人所不得不采纳的。因此,严格说来,柏格森的门人是不多的。有几本专为研究柏格森哲学而写的重要著作;我们现在只提出其中的两本来。狄包德(Thibaudet)著的“论柏格森主义” 相似文献
978.
979.
马克思在阐述资产阶级的政治经济学的发展时写道,随着资产阶级在英、法这样一些大国里夺得政权,资产阶级的政治经济学这门科学的丧钟也就敲响了。“从此以往,成为问题的,已经不是这个理论还是那个理论合于真理的问题,只是它于资本有益还是有害,便利还是不便利,违背警章还是不违背警章的问题。超利害关系的研究没有了,代替的东西是领津贴的论难攻击;无拘束的科学研究没有了,代替的东西,是辩护论者(Apologetik)的歪曲的良心和邪恶的意图。”马克思的这段话在很大程度上还可以用于资产阶级哲学。在帝国主义时代,这种哲学具有愈来愈多的辩解的和反动的性质。反动的哲学家们巧妙地 相似文献
980.