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251.
252.
Violations of stochastic transitivity on concurrent chains: Implications for theories of choice 下载免费PDF全文
Houston A 《Journal of the experimental analysis of behavior》1991,55(3):323-335
The concurrent-chains procedure has been used to measure how choice depends on various aspects of reinforcement, such as its delay and its magnitude. Navarick and Fantino (1972, 1974, 1975) have found that choice in this procedure can violate the condition of stochastic transitivity that is required if a unidimensional scale for reinforcements is to be possible. It is shown in this paper that two simple unidimensional models of choice on concurrent chains can produce violations of stochastic transitivity. It is argued that such violations may result from the complex contingencies of the concurrent-chains procedure. 相似文献
253.
In rural Appalachia in Tennessee, data on 13 female adolescents who had experienced a pregnancy (mean age=16 years, 7 months) were compared with those on 38 female adolescents who had not experienced a pregnancy (mean age-16 years, 4 months) to test the hypothesis that teenagers who experience a pregnancy have external attributions of control over their life events. The Nowicki-Strickland Locus of Control Scale for Children was administered to determine their beliefs about causes of events in their lives. All the girls were white and matched for socioeconomic status, housing, and cultural background. The mean attribution of control to external agents score stood at 14.5 for girls who had experienced a pregnancy compared with 12.7 for those who had not experienced a pregnancy, but the difference was not significant (p=.08).54% of the cases exhibited external attributional orientation compared with 16% of the controls (p.02). This finding concurred with that of earlier studies. The fact that not all the girls who had experienced a pregnancy had external attributional orientation suggested that it is not the only factor linked to adolescent pregnancy. Studies have not identified whether external attributional orientation is a causal factor or consequence of adolescent pregnancy. A 1980 study found that women who had shown more external locus of control scores during pregnancy and tended to castigate themselves had a high probability of postpartum depression. Another study indicated that rises in depression among adolescents were linked to prechange orientations toward external attributions of control. Practitioners should selectively pay attention to teenagers who have extreme attributional orientations since many teenagers carry their pregnancies to term and choose to rear their infants. These orientations appear to pose risks for the adolescent mother and her children. 相似文献
254.
Critics have questioned the value of human operant conditioning experiments in the study of fundamental processes of reinforcement. Contradictory results from human and animal experiments have been attributed to the complex social and verbal history of the human subject. On these grounds, it has been contended that procedures that mimic those conventionally used with animal subjects represent a "poor analytic preparation" for the explication of reinforcement principles. In defending the use of conventional operant methods for human research, we make three points: (a) Historical variables play a critical role in research on processes of reinforcement, regardless of whether the subjects are humans or animals. (b) Techniques are available for detecting, analyzing, and counteracting such historical and extra-experimental influences; these include long-term observations, steady state designs, and, when variables are not amenable to direct control (e.g., age, gender, species), selection of subjects with common characteristics. (c) Other forms of evidence that might be used to validate conditioning principles-applied behavior analysis and behavioristic interpretation-have inherent limitations and cannot substitute for experimental analysis. We conclude that human operant conditioning experiments are essential for the analysis of the reinforcement process at the human level, but caution that their value depends on the extent to which the traditional methods of the experimental analysis of behavior are properly applied. 相似文献
255.
绪论大家知道,世界上存在或者说存在过5000多种语言,但其中数百种已不再有任何个人或者语言社团使用。这些语言中的某些语言,诸如拉丁语,古希腊语和斯拉冯语等,维持着奄奄一息的生命,犹如供人瞻仰的古迹,今天尚能发挥的作用极为微弱,仅限于专业研究;其余大多数语言只对一小群语言学家、历史学家和把目光转向过去的其他专家有用。许多语言已了无生 相似文献
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在临床和实验研究文献中有大量的关于应激原影响免疫功能的描述性研究。虽然所观察到的改变与感染,新生物和自身免疫疾病的发病、病程和结果有关,但它们间是怎样的关系并不很清楚。尽管并不怀疑应激可能影响不同的免疫反应,但应激是通过什么机制改变淋巴和脊髓细胞的功能的,以及这些细胞为什么对应激的调节物质是敏感的,一直是模糊不清的。现在这些情况迅速改变了,有证据表明免疫系统对应激的敏感性并非偶然。在脑和免疫系统间存在着相互调制的作用。 相似文献
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本文为1985年6月14日在授予P.里克尔黑格尔奖时在斯图加特发表的演讲,论述里克尔的哲学思想在当代哲学思潮中的发展。 相似文献
260.
次协调逻辑(para-consistent logic)是那些把有意义的不协调理论形式化的逻辑。另一方面,辩证逻辑是把建立在黑格尔、马克思及其后继者提出的观念、原则之上的理论形式化的逻辑。这样的学科与次协调逻辑是相互交叉的。 相似文献