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81.
The COVID-19 pandemic has highlighted the need for further research evaluating the validity of conducting a battery of neuropsychological assessments virtually compared with face-to-face administration. Previous research has suggested that some neuropsychological assessments yield valid results when administered virtually, however, much of the previous research focused on older adults. To determine the validity of virtually administered neuropsychological tests, 28 healthy participants were assessed using a within-subjects, counter-balanced design. Participants completed a neuropsychological assessment battery covering tests of general intellectual functioning, memory and attention, executive functioning, language and information processing speed, as well as effort. There was no significant difference between face-to-face administration of the neuropsychological battery compared with virtual administration for the majority of the tests used. However, there were significant differences in the Colour Naming Task, with participants making fewer errors on the colour naming task and inhibition/switching task when administered virtually compared with face-to-face administration. There was also a significant age cohort effect in the inhibition/switching task. There was also a trending significant difference in mode of administration for the Verbal Fluency Task. Virtually administered neuropsychological assessments largely provide a valid alternative to face-to-face assessments; however, consideration must be given to test selection as well as the population of participants that are being assessed. Other important considerations must focus on preserving the security and integrity of test materials, as well as administration in a medico-legal setting. Future research should focus on validating assessments with specific patient populations and developing a neuropsychological assessment battery using information technology.  相似文献   
82.
A model for the analysis of paired comparison data is presented which combines features of the BTL-model with features of the Unfolding model. The model is metric, mathematically tractable, and has an exact algebraic solution. Since it is multidimensional and allows for individual differences, it is thought to be more realistic for some choice situations than either the Thurstone model or the BTL-model. No claim is made that the present model will be appropriate for all conceivable choice situations. Rather, it is argued that the fact that it is explicitly falsifiable is a point in its favor.This work was supported by a grant of the United States Public Health Service (1 R03 MH19139 01 MSM) and a David Ross (XR) grant of the Purdue Research Foundation (PRF 2132), both of which are gratefully acknowledged. We also owe thanks to Dr. Terry Cooper, whose careful scrutiny of an earlier draft of this paper allowed us to reduce the number of errors from n to n-1.  相似文献   
83.
Some relations between maximum likelihood factor analysis and factor indeterminacy are discussed. Bounds are derived for the minimum average correlation between equivalent sets of correlated factors which depend on the latent roots of the factor intercorrelation matrix . Empirical examples are presented to illustrate some of the theory and indicate the extent to which it can be expected to be relevant in practice.  相似文献   
84.
85.
Judgments of the acceptability of correct, word order reversed, and semantically anomalous sentences were elicited from 2- and 3-year-old children in a game played with hand puppets. All of the sentences used were simple imperatives and each child was asked to correct those he called wrong. Performance on the judgment task was correlated with each child's mean length of utterance and with his comprehension of reversible active and passive sentences. Only the linguistically most advanced children were able to make a significant number of appropriate judgments and corrections of reversed word order imperatives. Less developed children could appropriately judge and correct semantically anomalous but not incorrect word order imperatives. The importance of semantic as opposed to syntactic factors in children's judgments of the acceptability of sentences is stressed.This research was supported in part by PHS Grant HD-02908 from the National Institute of Child Health and Development. Roger Brown is the principal investigator.  相似文献   
86.
In the first of two experiments, it was demonstrated that an air puff elicited a reliable startle reflex in rats which showed no habituation over 50 trials. In the second study an attempt was made to measure an emotional response by recording startle reactions to the air puff during presentation of a presumed fear-eliciting CS. It was concluded that the air-puff-elicited startle reflex can be employed as an indirect measure of a hypothetical emotional response.  相似文献   
87.
The generation of satisfactory artificial speech involves a great variety of semantic, linguistic, and articulatory factors. Many of these complex elements are as yet unknown, and computers are used extensively for their investigation. An account of an on-line, interactive computer facility used for such research at Bell Laboratories is given. The use of this facility for exploring the duration and pitch correlates of stress in English sentences is described.  相似文献   
88.
Greeno and Steiner have shown that a three state Markov Chain with a single absorbing state is equivalent to many of the current formalizations of All-or-None learning theories. Distribution statistics and other summary statistics are derived from the general model. Expressions for the maximum likelihood estimators of its parameters and the sampling variances of the estimates are presented. Likelihood ratio tests for several different null hypotheses are derived. These tests permit one to evaluate the usual null hypotheses in terms of the parameters of a process model.This research was supported in part by a USPHS Predoctoral Research Fellowship, 1-F1-MH-31-289-01, by a grant from the Graduate School of the University of Texas, and by grant HD-02212-01 from the National Institute of Child Health and Human Development to Dr. John Theios.  相似文献   
89.
Procedures are described for the generation, synchronization. and accurate spacing of discrete dichotic stimulation material. A suggested standard definition of interpair interval is proposed.  相似文献   
90.
Stochastically textured patterns were used to investigate the sensitivity of Ss to differences in the statistical distributions of locally defined properties of element density and shape. The results of the study indicate that when the textures were most structured, in terms of their variance, Ss were most accurate at detecting dissimilarities between pairs of patterns. Ss also rated the similarity of the statistical distributions of elements of patterns differing in local properties. Multidimensional scaling analysis of the ratings showed two dimensions, representing monotonic orderings of the stimuli.  相似文献   
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