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31.
32.
Results are presented for the 1st analysis of the relationship between IQ and completed fertility using a large, representative sample of the US population. Correlations are predominantly negative for cohorts born between 1894 and 1964 but are significantly more positive for cohorts whose fertility was concentrated in the baby boom years. Previous studies reporting slightly positive correlations appear to have been biased in their restriction of samples to atypical cohorts. The National Opinion Research Center (NORC), a nonprofit research organization affiliated with the University of Chicago, conducted the General Social Survey (GSS) in the US each year from 1972 to 1982, except for 1979. A combination of block quota and full probability sampling was employed. Hour-long interviews were completed with 12,120 respondents who were English-speaking, noninstitutionalized adults (18 years or older) living within the continental US. Such questions as age, place of birth, income and occupation, were asked in each interview. Other questions about attitudes on various social, political, and moral issues were rotated in different years. The unique opportunity this data set affords is an overview of the relationship between intelligence and fertility for a nationally representative sample of Americans whose major reproductive years fell between 1912 and 1982. Data were consolidated from the 4 surveys in which the vocabulary test was given (1974, 1976, 1978, and 1982). Respondents were divided into 15 birth cohorts of 5-year intervals ranging from before 1894 to 1964. Correlations between vocabulary scores and number of siblings are markedly negative across all 15 cohorts. Vocabulary sibling correlations are more negative in every cohort than vocabulary offspring correlations. Previous reports of a neutral or slightly eugenic relationship appear to be due to the nature of the samples used, in part because the cohorts chosen were atypical, and in part because they did not include nonwhites. Childless respondents averaged slightly higher scores than did those with 1 or more children, indicating that the automatic exclusion of the childless from sibling-IQ studies has not spuriously inflated negative correlations. 相似文献
33.
Perone M 《The Behavior analyst / MABA》1985,8(2):185-189
Reactions to published accounts of research with human subjects, as well as research with nonhuman subjects, were assessed by examining citations in several samples of empirical articles in the Journal of the Experimental Analysis of Behavior. A stable, asymmetrical pattern emerged: Nonhuman research was cited in both human and nonhuman articles, but human research was cited primarily in human articles. Thus, human operant research appears to have had little influence on the nonhuman research which constitutes the bulk of the experimental analysis of behavior. Interpretation of this lack of impact depends on the functions one envisions for human research, several of which are discussed. 相似文献
34.
引言饮用含有咖啡因的饮料已遍及全球。大多数西方国家如美、英、法,习惯饮用咖啡;大多数东方国家如中、印、日,习惯用茶。还有一些国家喜欢饮含少量咖啡因的可可,“瓜拉那”等。据估计每年世界咖啡消费量已超过400万吨(Rokeitson,1978)。茶在中国的消费,也从1965年的43000吨,上升至1976年的139000吨(“中国经济年鉴”,1981)。为什么全世界范围内这样普遍地饮用咖啡和茶呢?原因是这些饮料中的咖啡因能提神解劳,提高感觉敏锐度和反应速度,使思路畅通,延长智力劳动的时间。如Nash(1962)的研究表明,咖啡因有助于成对联想学习,听觉材料的及时回忆,以及完成不完整的句子。但是近年来人们发现,咖啡因对人体有有害的作用。摄入咖啡因后,其中的甲基黄嘌呤 相似文献
35.
在阿尔都塞的马克思著作研究中,多元决定和结构因果性这两个概念是十分重要的。本文将通过考察阿尔都塞对这两个概念在理解马克思的“方法论”上的价值和应用的论述,来解释这两个概念。但这种研究方法并不认为在《资本论》或其他著作中,马克思实际上有一种具体的或明确的方法论。对我们来说,马克思主义中是否有方法论仍然是一个未解决的问题。对于任何的马克思方法论的探讨,这些概念都是重要的。本文的任务之一就是表明,马克思在政治经济学中的贡献和“理论革命”不能简单地用方法论来描绘。马克思对黑格尔的辩证法思 相似文献
36.
Modulation of the responses to perturbation applied during different phases of three rhythmic movements in humans-running, cycling, and hopping-was studied. The perturbation was an electrical stimulus. The results showed gating and modulation of the responses in both ipsi- and contralateral limb muscles. The responses during running and cycling were only excitatory in nature, while during hopping an inhibitory response was observed. These responses were not correlated with the normal activity during the movement. The latency of the response in general was not altered for different stimulation phases. The alterations in the step cycle demonstrated overt behavioral changes due to the responses. There were differences between the responses observed during these movements and walking. In running, the major adaptation to perturbations appears to be in the contralateral side as seen in the changes in the step cycle. During cycling (except for one phase) and hopping, the same set of muscles was activated in response to perturbation. This represents a simplifying strategy in response organization. The dependency of the response on the task characteristics, postural stability requirement, and external constraints imposed on the subject is discussed. These studies provide insights into task-dependent strategies adopted by the nervous system to meet unexpected perturbation during rhythmic movements in humans. 相似文献
37.
Rats were trained on concurrent schedules in which pressing one lever postponed shock and pressing the other occasionally produced a 2-min timeout during which the shock-postponement schedule was suspended and its correlated stimuli were removed. Throughout, the shock-postponement schedule maintained proficient levels of avoidance. Nevertheless, in Experiment 1 responding on the timeout lever was established rapidly, was maintained at stable levels on variable-interval schedules, was extinguished by withholding timeout, was reestablished when timeout was reintroduced, and was brought under discriminative control with a multiple variable-interval extinction schedule of timeout. These results are in contrast with Verhave's (1962) conclusion that timeout is an ineffective reinforcer when presented to rats on intermittent schedules. In Experiment 2 the consequence of responding on the timeout lever was altered so that the shock-postponement schedule remained in effect even though the stimulus conditions associated with timeout were produced for 2 min. Responding extinguished, indicating that suspension of the shock-postponement schedule, not stimulus change, was the source of reinforcement. By establishing the reinforcing efficacy of timeout with standard variable-interval schedules, these experiments illustrate a procedure for studying negative reinforcement in the same way as positive reinforcement. 相似文献
38.
39.
本文着重反映了当前苏联实验心理学发展的一些情况,强调了心理学实验联系实际的意义:强调了马列主义学说的指导作用;强调在科学知识的总体系中,实验占有光荣的地位以及实验心理学研究的进一步发展需要利用新的枝术成就:强调研究心理学发展的历史等。并对实验心理学的发展趋势提出了一些看法,代表了当前苏联一些心理学家的观点。 相似文献
40.
动机过程影响儿童对知识和技能的获得、迁移和使用,但与教育有关的动机概念仍难以捉摸。美国伊利诺斯大学心理学家C.S.Dweck利用社会-认知框架中的最新研究,描述了适应和适应不良动机模式,提出了一个以研究为基础的动机过程模型。这个模型表明儿童在认知任务中所追求的特定目标如何决定他们对成功和失败的反应、如何影响他们认知操作的质量。Dweck认为这种探索对改变适应不良动机过程的干预的设计和实践有重大意义。她根据这个模型解释了动机对数学成绩的性别差异的影响,她观察到以经验为基础的干预可以防止当前的这种成绩差异。 相似文献