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991.
记录7名左颞叶癫痫病人和9名正常人在四种实验条件下的事件相关电位:(1)听觉脑子诱发电位,(2)红色闪光刺激,(3)陌生人嗓音识别,(4)陌生人面孔识别。实验结果发现,两组被试在视觉信息加工中无差异,在嗓音识别中病人的N150和P300波潜伏期大于正常人,表明其复杂听觉认知功能受到影响.红色闪光刺激和噪音识别条件下,病人的P100波幅大于正常人,说明病人对强刺激的物理强度有较高的反应水平,不易习惯化。 相似文献
992.
The ideal of scientific openness — i.e. the idea that scientific information should be freely accessible to interested parties — is strongly supported throughout the scientific community. At the same time, however, this ideal does not appear to be absolute in the everyday practice of science. In order to get the credit for new scientific advances, scientists often keep information to themselves. Also, it is common practice to withhold information obtained in commissioned research when the scientist has agreed with his or her employer to do so. The secrecy may be intended for ever, as in the military area, but also temporarily until a patent application has been made. The paper explores to what extent such secrecy is undesirable, as seems to be suggested by the ideal of scientific openness. Should this ideal be interpreted as having certain exceptions which make the above-mentioned practices acceptable? Are there, on closer inspection, good arguments for the ideal of scientific openness, and for officially upholding it? Possible versions of the ideal of scientific openness are explored and the issue is found to be rather complex, allowing for wide variations depending on the acting parties, beneficiaries, types of information and moral requirements involved. We conclude that the arguments usually given in favour of this ideal are weaker than what seems to be generally believed, and that, on closer inspection, they leave plenty of room for exceptions to it. These exceptions only partly cover the actual practice of withholding scientific information, and there may still be good reason to advocate, teach and enforce the ideal of scientific openness within the scientific community. 相似文献
993.
994.
It has been proposed that use of socially acquired information by animals should increase as the time available for individual
resource sampling decreases. We gave Norway rat “observers” either 2 or 5 h day–1 to sample four foods. Three of these foods were relatively palatable, but protein-poor; the fourth was relatively unpalatable,
but protein-rich. We found that observer rats that for 2 h day–1 both sampled foods and interacted with demonstrators eating only the protein-rich food ate more of the protein-rich food
than did observers that sampled for 2 h day–1 but had no opportunity to interact with demonstrators. On the other hand, observer rats that could sample foods for 5 h day–1 ate equal amounts of protein-rich food whether they interacted with a demonstrator fed protein-rich food or not. Subsequent
analyses showed that the time available to observers to sample foods, rather than the opportunity to interact with demonstrators
determined whether such interaction influenced observers’ food choices. The results are consistent with the hypothesis that
animals increase their use of public information in response to temporal constraints on opportunities for resource sampling.
Received: 22 December 1998 / Accepted after revision: 27 February 1999 相似文献
995.
信息的性质对内隐社会印象的影响 总被引:4,自引:0,他引:4
为了考察信息的性质对社会印象的影响,通过语义差异法建构了具有六个维度的社会印象量表;采用2×2×8的混合设计,给被试提供自然信息和七类不同性质的社会信息(组内设计),考察了评价人和被评价人性别特征(组间设计)在社会印象形成过程中的作用;同时,还测量了被试的外显性别态度。结果表明,在否定个人智慧、社会地位、性别特征和品质特征时,所形成的社会印象在被评价人性别特征上表现出了差异,并且男女被试都表现出了“好人主义”倾向;在外显性别态度上男女被试设有差异;此外,还分析了用语义差异法测量内隐社会印象的适用性。 相似文献
996.
Human observing: Maintained by stimuli correlated with reinforcement but not extinction 总被引:4,自引:4,他引:0 下载免费PDF全文
College students received points exchangeable for money (reinforcement) on a variable-time 60-second schedule that alternated randomly with an extinction component. Subjects were informed that responding would not influence either the rate or distribution of reinforcement. Instead, presses on either of two levers (“observing responses”) produced stimuli. In each of four experiments, stimuli positively correlated with reinforcement and/or stimuli uncorrelated with reinforcement were each chosen over stimuli correlated with extinction. These results are consistent with prior results from pigeons in supporting the conditioned-reinforcement hypothesis of observing and in not supporting the uncertainty-reduction hypothesis. 相似文献
997.
The purpose of this research is to assess the extent to which judgmental forecasts are improved by having more contextual and technical knowledge. Contextual information is knowledge gained by practitioners through experience on the job, consisting of general forecasting experience in the industry as well as specific product knowledge. Technical knowledge is knowledge about data analysis and formal forecasting procedures, including information on how to analyze data judgmentally. We directly compared judgmental forecasts of business practitioners with those generated by students, using 22 real-world time series. The practitioners had considerable contextual but no technical knowledge. The students had no contextual but two different levels of technical knowledge. We also generated forecasts with statistical methods to benchmark performance. Results show that contextual knowledge is particularly important in making good judgmental forecasts, while technical knowledge has little value. Practitioner forecasts are better than student forecasts in almost all comparisons. A decisive factor affecting forecast performance appears to be data variability, measured by the coefficient of variation of the time-series data. As the variability of a time series increases, the performance of all forecasts deteriorates, but judgmental forecasts by practitioners become more preferable. Statistical methods have difficulty achieving reasonable forecasts when the data are more variable, whereas judgemental forecasts reinforced by contextual information do relatively well. Data variability is one explanation for the mixed findings of past studies, relative to how well statistical techniques compare with judgment as a forecasting method. 相似文献
998.
Sue R. Beers 《Neuropsychology review》1992,3(4):281-320
A comprehensive review of recent neuropsychological studies of mild head injury (MHI) involving children and adolescents is presented. The seminal work of Rutter and his colleagues is reviewed. An alternative conceptualization of MHI as proposed by various researchers is elaborated and further research investigating the cognitive sequelae of MHI is reviewed. MHI is discussed within the context of development and information processing models. Finally, the sequelae of MHI are reviewed with respect to academic functioning. Methodological problems inherent in studies of MHI are identified and discussed. The studies reviewed here support the conclusion that both the cognitive and emotional consequences of MHI should receive serious evaluation. 相似文献
999.
1000.