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101.
Anthony J. Cuvo Paula K. Davis Mark F. O'Reilly Brenda M. Mooney Ruth Crowley 《Journal of applied behavior analysis》1992,25(2):477-489
We assessed whether written task analyses would serve as textual prompts for performing functional tasks by persons with mild disabilities. Several variables that could influence the effectiveness of textual prompts to promote stimulus control were examined across four groups. A consistent finding was that written specific task analyses combined with end-of-trial performance feedback were effective for promoting the acquisition and generalization of several tasks. Performance transferred immediately to natural discriminative stimuli when the written task analyses and feedback were withdrawn for most tasks and participants. For 2 participants, transfer of stimulus control was accomplished by prompt fading, using individualized written task analyses either with or without performance feedback (Group 1). When feedback was not provided, the effectiveness of written specific task analyses was inconsistent across groups. In contrast to the controlling effects of written specific task analyses, written generic task analyses, which specified only major task outcomes, when combined with performance feedback (Group 1) did not control responding. Overall, this research demonstrated the effectiveness of written specific task analyses and performance feedback to promote stimulus control for persons with mild disabilities. 相似文献
102.
The detectability of surface curvatures defined by optical motion was evaluated in three experiments. Observers accurately detected very small amounts of curvature in a direction perpendicular to the direction of rotation, but they were less sensitive to curvatures along the direction of rotation. Variations in either the number of points (between 91 and 9) or the number of views (from 15 to 2) had little or no effect on discrimination accuracy. The results of this study demonstrate impressive visual sensitivity to surface curvature. Several characteristics of this sensitivity to curvature are inconsistent with many computational models for deriving three-dimensional structure from motion. 相似文献
103.
M Zivkovi? 《Perceptual and motor skills》1992,75(1):79-90
The quotient of the mean quantitative score on Initial-letter Word-association Test for 193 normal subjects was significantly higher than the quotient of the mean quantitative score of 44 abnormal (psychotic) subjects. This is interpreted as meaning that, in general, the normal subjects have predominantly a positive attitude towards their surrounding world in contradistinction to the abnormal subjects whose attitude was predominantly negative, ambivalent, and repressive. On the other hand, the mean of the quotients of the quantitative scores of the 44 abnormal subjects was higher than the mean of the quotients of the quantitative scores of the normal subjects which suggests increased oral tendencies of the abnormal subjects expressed much as the unwarranted optimism of small children. 相似文献
104.
R B?sel 《Zeitschrift für experimentelle und angewandte Psychologie》1992,39(3):372-395
Based on previous findings (B?sel et al., 1990) it was assumed that in concept learning tasks generating on hypotheses on a concept which has to be developed is accompanied by increases of the Alpha 1 power (7.5-10 Hz) in the spontaneous EEG activity. In this study 16 subjects performed five problem solving tasks with similar processing requirements. EEG data were analyzed by means of post hoc comparisons of subjects differing in performance quality. Additionally, four control tasks were employed in which, based on previous studies, variations in the Theta frequency range were expected. An effect in the Alpha 1 frequency band was observed in tasks requiring reconstructive recall or testing the usefulness of an mathematical algorithm. The creation of a rank order or mental map is accompanied by power increases in the lower portions of the Alpha 1 frequency band (7.5-8.5 Hz). Moreover a high amount of controlled variance (eta2 up to 34%) was obtained for this effect. Increases in EEG Theta power, which presumably indicate subjects' component analysis, were found before the subjects recognized parts of geometric figures or before relevant features in the "buddhist monk problem" were discriminated. The dynamics of EEG power over time is in examples of frequency/time plots in a figure, illustrated. 相似文献
105.
L J?ncke 《Zeitschrift für experimentelle und angewandte Psychologie》1992,39(3):434-454
Twenty male subjects (Ss) were repeatedly confronted for five seconds to pictures with positive, negative and neutral valence. During the picture presentation facial EMG-reactions of five mimic muscles (m. frontalis lateralis, m. corrugator supercilii, m. orbicularis oculi, m. zygomaticus major on the right and left side of the face) were recorded. In addition, heart rate was measured. It could be shown that during repeated presentation of pictures with positive valence the m. orbicularis oculi and the m. zygomaticus major on both sides of the face yielded enhanced average EMG-reactions as compared to the repeated presentation of pictures with negative and neutral valence. During presentation of pictures with negative valence the m. frontalis lateralis and the m. corrugator supercilii revealed enhanced EMG-reactions as compared to the repeated presentation of pictures with positive valence. Furthermore, it could be shown that during the repeated presentation of pictures with positive valence those facial muscles which mainly react during confrontation with pictures of positive valence showed a continuous decrease of EMG-activity. Facial muscles which mainly react during the presentation of pictures with negative valence do not show a continuous decrease in EMG-activity during the course of the repeated presentation of pictures with negative valence. Additionally, the EMG-activity of the m. zygomaticus major on the right and lift side of the face do not differ with respect to the mean activity and the time course during confrontation of pictures with positive valence. The m. orbicularis oculi yielded enhanced EMG-reactions during the presentation of pictures with positive valence as compared to both m. zygomaticus major muscles. The present results are discussed with respect to psychobiological theories concerning facial expression. 相似文献
106.
30 subjects participated in a discrimination experiment learning face-letter associations under four rotation conditions (45 degrees, 90 degrees, 135 degrees, 180 degrees). Under each condition two thirds of the faces were presented twice, upright and rotated away from the vertical; the remaining faces were presented once, upright or rotated. Learning is described by a joint Markov model: For faces that are presented twice it assumes a separate association and encoding process (two-stage-model), for faces that are presented once it assumes an association process (all-or-none-model). The Markov model fits the data for all four rotation conditions. The angle of rotation does not affect learning for faces that are presented once. For faces that are presented twice it influences both the association and the encoding process. For the angles employed, the effect of rotation can be approximated linearly. The results suggest that the encoding of a rotated face differs increasingly from an upright face as a function of these angles of rotation. This confirms analogous conclusions from mental rotation experiments. 相似文献
107.
Dr. Alastair J. Flint Sandra E. Black Irene Campbell-Taylor Gillian F. Gailey Carey Levinton 《Journal of psycholinguistic research》1992,21(5):383-399
In its early stages, Parkinson's disease (P.D.) may be difficult to distinguish from major depression (M.D.) leading to inappropriate management. Both illnesses are characterized by psychomotor retardation. The neurovegetative symptoms used to diagnose M.D. are not specific and in P.D. may be due to the physical illness itself. Currently, differentiation of the two disorders relies on subjective clinical observation. Improved diagnostic accuracy based on more objective data is needed. To this end, this study used computerized acoustic analysis to contrast speech patterns in P.D. and M.D. The sample consisted of 30 P.D. patients without depression or dementia, 30 patients with uncomplicated M.D., and 31 normal controls, each 60 years of age or over. Of the acoustic variables studied, M.D. patients had significantly reduced rates of speech compared with P.D. patients. The data suggest that this temporal measure of speech may be useful in the differentiation of P.D. and M.D. 相似文献
108.
Recently, several outstanding discussions of the structure of non-consequentialism have appeared. Two of these are Shelly Kagan's The Limits of Morality and a pair of articles by Warren Quinn, "Actions, Intentions, and Consequences: the Doctrine of Doing and Allowing" and "Actions, Intentions, and Consequences: the Doctrine of Double Effect." I would like to examine several related issues discussed by these authors. Another outstanding work to which I will refer in this article, but not discuss at great length, is Judith Jarvis Thomson's The Realm of Rights. The general topic with which I shall be concerned is the structure of a non-consequentialist moral theory. Non-consequentialism has two important features. In a non-consequentialist moral theory, (1) there is a permission not to maximize overall best consequences (this is sometimes referred to as an option), and (2) there are constraints on promoting overall best consequences (for example, we must not kill one innocent, non-threatening person for his organs to save five others). I shall use the works by Kagan, Quinn, and Thomson to help characterize further the elements of the non-consequentialist structure and to justify them. 相似文献
109.
Fourth- and seventh-grade children and college-age adults proofread passages typed either in lowercase or in all capital letters. Words were misspelled by deleting one of four letters, s, c, k, or p, that have similar features in lowercase and uppercase. Proofreading errors decreased with age and increasing reading ability, but all of the subjects were sensitive to changes in word shape--they missed more words with deletions of s or c than k or p in the lowercase passage but not in the all-capitals passage. These findings indicate that word shape is an important variable in recognizing familiar words, even for young readers. 相似文献
110.
Three experiments are reported that represent a reexamination of the missing-number method (Buschke, 1963b) of estimating short-term memory span. The missing-number task involved presenting a random sequence of all but one of the numbers of a known reference set and asking subjects to identify the missing number. Experiment 1 introduced a modified missing-number task that included two missing items and two choices made by the subject. With a large decline in performance for the second choice relative to the first, it is possible that only the second choice was subject to output or retrieval interference. An alternative explanation is that subjects output the number with the weakest memory representation as their first response. By postcuing subjects to report their two choices in a forward or backward sequence, Experiment 2 provided evidence against the importance of output interference and support either for the importance of retrieval interference or for the "weakest-first" hypothesis. However, with a paradigm that replaced only correctly identified missing numbers, a prediction that subjects would select the number with the weakest memory representation as their first response was not confirmed in Experiment 3. Instead, retrieval interference was implicated to explain the first-choice superiority found in Experiments 1 and 3. The results were interpreted in terms of the TODAM model of Murdock (1982, 1987, in press). 相似文献