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811.
Special difficulties are encountered when attempting to provide intracranial cannulation of small animals that have floating or fragile skull bones. The technique described was developed for mice but seems applicable to other species. The cannula system is inexpensive and easy to use. A wound clip anchor seems superior to either skull screws or bonded acrylic, producing less damage to the brain and no necrosis of bone or tissue on the wound margin. Patency data up to 25 days is presented, and the system is as efficacious as other techniques.  相似文献   
812.
A new method for the analysis of complex avian song repertoires is introduced. The method consists of sending a tape-recorded bird-song signal through five narrow band-pass filters and then to a five-channel high-speed pen recorder. A coding method that allows a researcher to convert the output from the pen recorder to numbers for later analysis by computer is described.  相似文献   
813.
Concurrent mental activity seems to be a significant, nonvisual factor affecting the human accommodation response. Two experiments were conducted to determine the direction and magnitude of this accommodation response. Experiment 1 employed a concurrent, written backwards counting task. Experiment 2 employed a concurrent, mental imagery task of “thinking near” and “thinking far.” In both experiments, the concurrent secondary task effected a cumulative accommodative shift toward the visual far point of from .25 to .75 diopter away from a near (3.0 diopter) target. This accommodative shift was observed only in the presence of a stimulus field and not in open-loop (analogous to empty-field) conditions. In addition, a long-term instability in the open-loop method of obtaining the dark focus was observed. Similarities between this accommodative shift and the pupillary response are noted. The accommodation response is discussed in relationship to both an attention-sharing and an involuntary autonomic response model.  相似文献   
814.
Attention, Perception, & Psychophysics - This study concerns the stereophenomenon obtained with binocular viewing of dynamic visual noise with a neutral density filter over one eye. Such a...  相似文献   
815.
816.
Conclusion The above arguments have not conclusively demonstrated the existence of value; nor have they sought to. Rather, they have focused primarily on value-language itself: what it is, what it means, and how men use it. In value-judgements, men intend to speak about reality, and not merely to manifest their feelings to influence others. The conceptual character of value-words gives them a formal objectivity lacking in mere manifestations of feeling; the meaning of value-words contains a claim to objectivity arising from the ontological claim to objectivity of value itself.These facts demonstrate conclusively that value-language differs essentially from emotive manifestations of feeling. Therefore, and in contradiction to both Ayer and Stevenson, even the most abstract of value-words can be used to form legitimate, conceptually meaningful value-judgements. As judgements, value-judgements can be true or false, not because of any factual content, but specifically as conceptually meaningful, pure value-judgements.I have deliberately restricted these investigations to consideration of language, without seriously arguing the ontology of value itself. Thereby, I have met the emotivists on their own ground. Even without demonstrating the existence of value, I have shown their analysis of value-language to be flawed. Further, I have identified a unique claim to objectivity in value-language which argues strongly in favor of the real existence of value as its ultimate foundation.For the simplest, most obvious explanation of this claim to objectivity is that it refers to value, which actually exists. That proof is logically the next step in my argument. A good place to begin would be a more careful, detailed analysis of the structure of human responses such as admiration, love, enthusiasm, etc., seeking to determine what they ontologically presuppose. Proof of the real existence of value would demonstrate the ontological grounds for the claim to objectivity of value-language. It would show that value-language is rooted in the real world, speaking of reality as it is. This would be the last, and most important sense in which value-language is meaningful and objective.
  相似文献   
817.
The study investigated the impact of a Summer Therapeutic Daycamp on the subsequent classroom behavior of behaviorally disordered children. Pre-post assessment of the maladaptive behavior of children participating in the program and of a control group one year subsequent to the program demonstrated the differential impact of the program, consistent with the notion of intensive, time-limited intervention as an effective alternative to extended treatment.  相似文献   
818.
The present studies assessed the degree of stimulus control exerted by S+ and S? without confoundings of stimulus novelty and stimulus ambiguity. In Experiment 1, rats were trained on two intercurrent simultaneous discrimination problems with nine times more training given on one than the other. Then the animals were given transfer tests with re-paired stimuli. The results showed that S? exerts greater stimulus control than S+ in a two-choice simultaneous discrimination. Experiment 2 provided a test of the possibility that the relative degree of control by S? varies with different amounts of training. Three groups were trained on two intercurrent simultaneous discrimination problems; each group was given 7, 11, or 15 times more training on one problem than the other. Then transfer tests were given with re-paired stimuli. Again the results showed that S? exerts greater stimulus control than S+ in a two-choice simultaneous discrimination.  相似文献   
819.
In two interview studies subjects were asked what memory aids they used and how often. In particular, the reported frequencies of use of external aids such as shopping lists and memos were compared with those of internal aids that have been investigated by psychologists, such as the method of loci. Subjects in the first study were 15 male and 15 female university students, and in the second, a group of 30 adult women, most of whom were housewives. In both studies the aids reported to be used most were external ones. However, it is pointed out that the most commonly used methods of remembering must be internal, although these are not usually considered to be aids. Some difficulties that arise in the assessment of memory in interview and questionnaire studies are discussed.  相似文献   
820.
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