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991.
Statistical analysis of timing errors. 总被引:8,自引:0,他引:8
Human rhythmic activities are variable. Cycle-to-cycle fluctuations form the behavioral observable. Traditional analysis focuses on statistical measures such as mean and variance. In this article we show that, by treating the fluctuations as a time series, one can apply techniques such as power spectra and rescaled range analysis to gain insight into the mechanisms underlying the remarkable abilities of humans to perform a variety of rhythmic movements, from maintaining memorized temporal patterns to anticipating and timing their movements to predictable sensory stimuli. 相似文献
992.
Four experiments examined change in confidence after hearing two sides of a dispute. The results showed that a case independently judged to weakly support one side often increased confidence that the opposing side was correct. Furthermore, the stronger the first case, the more likely a subsequent weak case had a reverse impact. Traditional belief‐updating models, which tend to focus on change in belief after individual pieces of evidence rather than entire cases, cannot account for these results, and a model that can account for them is introduced. In the new model, case strength is evaluated with respect to a relatively demanding (and malleable) reference point. A weak case can fall below this demanding reference point, resulting in a reverse impact on confidence. Cases must exceed relatively high strength thresholds in order to have their intended impact because they are expected to be biased summaries of evidence. When it is clear that a weak case is unbiased, it affects confidence in the intended direction. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
993.
Xiang Chen 《Journal for General Philosophy of Science》2002,33(1):1-22
This paper examines taxonomy comparison from a cognitive perspective. Arguments are developed by drawing on the results of
cognitive psychology, which reveal the cognitive mechanisms behind the practice of taxonomy comparison. The taxonomic change
in 19th-century ornithology is also used to uncover the historical practice that ornithologists employed in the revision of
the classification of birds. On the basis of cognitive and historical analyses, I argue that incommensurable taxonomies can
be compared rationally. Using a frame model to represent taxonomy, I show how rational comparisons were achieved in the historical
case through compatible contrast sets and attribute lists. Through analyzing the cognitive processes of classification and
concept representation, I further explain how rival taxonomies in the historical case could be rationally compared on ‘platforms’
rooted in such cognitive mechanisms as relational assumptions and preferences for body parts in conceptual processing.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
994.
Ethiopian Jewish immigrants in Israel are one of the most ancient communities in the world, one that has been detached from
the known Jewish world for about 2,500 years. Throughout this very long period of isolation, the Ethiopian Jewish community
maintained Jewish tradition and dreamed over the centuries to unite with the rest of the Jewish world and immigrate to the
Jewish state—Israel. But this transition occurred within a short time from an agrarian society in Ethiopia (traditional culture)
with an oral culture to a knowledge society in Israel (modern culture) with a written culture. Most studies that examine cultural
transition focus on anthropological, sociological, and cultural aspects; but there are nearly no studies that examine the
technological knowledge of non-literate populations. The purpose of this study is to examine and characterize technological
knowledge among this population—the case of Ethiopian non-literate immigrants in Israel. The study involved in-depth interviews
to examine technological knowledge through using technological appliances in their everyday life, assembly of two simple technological
systems, and a home technology profile compared to the general population in Israel. Participants included 50 non-literate
Ethiopian immigrants between the ages of 40–60. The results of our study are surprising in that we have shown that non-literate
immigrants adapt to a technology-rich environment at an average degree with respect to the general population in Israel. Also,
comparing technological knowledge between traditional and modern cultures shows participants’ wide range of knowledge without
ability to read and write. Illiteracy does not preclude the development of knowledge in general, technological knowledge particularly,
and does not prevent non-literate populations from acquiring knowledge in a new environment. 相似文献
995.
996.
997.
Cathy Yi Chen 《Journal of Consumer Psychology》2009,19(3):416-426
Drawing from self-construal studies on cognitive styles as well as reference price literature, this research investigates the impact of independent versus interdependent self-construal on consumers' use of internal reference prices (IRPs) and external reference prices (ERPs) during price evaluations. Three experiments reveal that IRPs have a larger impact on price evaluations for participants who are primed with an independent (vs. interdependent) self-construal, whereas ERPs have a larger impact for participants who are primed with an interdependent (vs. independent) self-construal. The differential impact of self-construal on the use of IRPs and ERPs seems to be mediated by a generalized, perceived sense of connectedness/separateness. Implications on reference price research, self-construal and cognitive styles are discussed. 相似文献
998.
Norman M. Weinberger Alexandre A. Miasnikov Jemmy C. Chen 《Neurobiology of learning and memory》2009,91(3):273-286
Memories are usually multidimensional, including contents such as sensory details, motivational state and emotional overtones. Memory contents generally change over time, most often reported as a loss in the specificity of detail. To study the temporal changes in the sensory contents of associative memory without motivational and emotional contents, we induced memory for acoustic frequency by pairing a tone with stimulation of the cholinergic nucleus basalis. Adult male rats were first tested for behavioral responses (disruption of ongoing respiration) to tones (1–15 kHz), yielding pre-training behavioral frequency generalization gradients (BFGG). They next received three days of training consisting of a conditioned stimulus (CS) tone (8.00 kHz, 70 dB, 2 s) either Paired (n = 5) or Unpaired (n = 5) with weak electrical stimulation (~48 μA) of the nucleus basalis (100 Hz, 0.2 s, co-terminating with CS offset). Testing for behavioral memory was performed by obtaining post-training BFGGs at two intervals, 24 and 96 h after training. At 24 h post-training, the Paired group exhibited associative behavioral memory manifested by significantly larger responses to tone than the Unpaired group. However, they exhibited no specificity in memory for the frequency of the tonal CS, as indexed by a flat BFGG. In contrast, after 96 h post-training the Paired group did exhibit specificity of memory as revealed by tuned BFGGs with a peak at the CS-band of frequencies. This increased detail of memory developed due to a loss of response to lower and higher frequency side-bands, without any change in the absolute magnitude of response to CS-band frequencies. These findings indicate that the sensory contents of associative memory can be revealed to become more specific, through temporal consolidation in the absence of non-sensory factors such as motivation and emotion. 相似文献
999.
Alexandre A. Miasnikov Jemmy C. Chen Norman M. Weinberger 《Neurobiology of learning and memory》2009,91(3):298-309
Specific behavioral associative memory induced by stimulation of the cortically-projecting cholinergic nucleus basalis (NB) is dependent on intrinsic acetylcholine and shares with natural memory such features as associativity, specificity, rapid formation, consolidation and long-term retention. Herein, we examined extinction and the effects of stimulus pre-exposure. Two groups of adult male rats (n = 4 each) were first tested for behavioral responses (disruption of ongoing respiration) to tones (1–15 kHz), constituting a pre-training behavioral frequency generalization gradient (BFGG). They next received a first session of training, 200 trials of a tone (8.00 kHz, 70 dB, 2 s) either paired with electrical stimulation of the NB (100 Hz, 0.2 s, ~67 μA, NBstm) (group IP) or unpaired (group IU). Twenty-four hours later, they were tested for behavioral memory by obtaining post-training BFGGs. Then the contingencies were reversed yet another 24 h later; the IP group received tone and NBstm unpaired and the IU group received them paired. A final set of generalization gradients was obtained the next day. All stimuli were presented with subjects under state control indexed by regular respiration. Tested 24 h post-initial training, the IP group developed specific associative behavioral memory indicated by increased responses only to CS-band frequencies, while the IU group did not. After subsequent training with unpaired stimuli, the IP group exhibited experimental extinction. Furthermore, after initial exposure to the CS and NBstm unpaired, the IU group exhibited a tendency toward reduced conditioning to CS/NBstm pairing and a significant increase in latency of conditioned responses. The present findings provide additional support for the hypothesis that engagement of the NB is sufficient to induce natural associative memory and suggest that activation of the NB may be a normal component in the formation of natural associative memory. 相似文献
1000.