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951.
Munetomo Nakata M.D. Jiro Mukawa Gerhard H. Fromm 《Integrative psychological & behavioral science》1993,28(4):343-352
Since Berger’s discovery of the electroencephalogram (EEG), its analysis has been generally restricted to the visual range
(upmost 100Hz) and has ignored higher frequency components. One reason should be that there are no reliable methods to distinguish
the brain potentials from muscle activity. We have introduced fluctuation analysis, which is popular method especially in
the field of basic physiology to clinical electrophysiology. In our previous study, it was declared that power spectral density
(PSD) of human high frequency EEG was composed of double Lorentzians and vanished into white level within 1kHz. Then the purpose
of this study is to elucidate the “Automated Fluctuation Analysis,” which enables us to evaluate these higher frequency components
and its physiological meaning especially focused on conscious level from wakefulness to sleep stage 1. Seventy-four scalp
recording EEGs in twenty normal subjects were studied. In short, “Automated Fluctuation Analysis” is made of three steps:
amplification of EEG signal, A/D conversion and Fast Fourier Transform by signal processor and extraction of Lorentzian parameters.
PSD of high frequency EEG was displayed on log-log graph and the algorithm fit to the following Lorentzian formula were mathematically
based on Brown & Dennis. S(f)=S1/ [1+(f/fc1)2] + S2/ [1+(f/fc2)2], where S(f) is PSD (μ V2/Hz) at each frequency (f;Hz), S1 and S2 are the plateau level or zero-frequency power of the initial and second Lorentz,
and fc1 and fc2 are the corner or half-power frequency of the initial and second Lorentz, respectively. As results, during wakefulness the
PSD of high frequency EEG activity was composed of double Lorentzian fluctuations and the power distribution of S1 value in
topographical display was frontal dominant. This pattern of S1 value disappeared and S2 value became lower during sleepiness
and the second Lorentz disappeared during sleep. 相似文献
952.
Torbjörn Tännsjö 《Theoretical medicine and bioethics》1993,14(3):231-247
Should we change the human genome? The most general arguments against changing the human genome are here in focus. Distinctions are made between positive and negative gene therapy, between germ-line and somatic therapy, and between therapy where the intention is to benefit a particular individual (a future child) and where the intention is to benefit the human gene-pool. Some standard arguments against gene-therapy are dismissed. Negative somatic therapy is not controversial. Even negative, germ-line therapy is endorsed, if the intention is to cure a certain individual (a future child). In rare cases, positive therapy on somatic cells may be warranted. Germ-line therapy may become a valuable method of preventing harm, through ‘genetic vaccination’. If safe methods evolve, it is harmless (though vain), to try to achieve more ambitious goals. Prospective parents should not be prevented from exercising this harmless kind of parental authority. The paper concludes: Thereis a moral limit to how much we ought to manipulate the human genome, however. We ought not to jeopardize the continued existence of mankind. We ought not to develop methods of germ-line therapy intended in a radical manner to improve human nature, and we ought to leave to prospective parents to decide in individual cases what kind of intervention shall take place. 相似文献
953.
The phonemic errors of three Finnish Broca's aphasics were analyzed according to various phonological features, frequency of segments, syllable, word, and stress positions, as well as for the phonotactic structure of the uncanonical products. It was found, e.g., that the distance between the syntagmatic error and its source could not be satisfactorily counted by phonemes, since the syllable had to be taken into account also in pathological Finnish. As regards the paradigmatic dimension of the errors, the number of incorrect features is even here in reverse relation to the frequency of the erroneous phonemes. Moreover, it was found that pure quantity errors and vowel harmony deviations are infrequent in the speech of Finnish Broca's aphasics. 相似文献
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The purpose of this study is to examine the reported level of self-disclosure in online communication and understand the relationship between perceived interpersonal competence and self-disclosure in an online context, taking into account the moderating role of shyness. The study sample consists of university students (N = 585). Hierarchical multiple linear regression analyses revealed that, controlling for participants' online media use, shyness moderated the relationship between online self-disclosure and perceived interpersonal competence. Moderation results showed that the relationship between online self-disclosure and perceived interpersonal competence was weaker for individuals with higher levels of shyness, and stronger for those with moderate or low scores on the shyness measure. The study's implications and contributions to the existing literature are discussed. 相似文献
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