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61.
Nondeterministic programs occurring in recently developed programming languages define nondeterminate partial functions. Formulas (Boolean expressions) of such nondeterministic languages are interpreted by a nonempty subset of {T (“true”), F (“false”), U (“undefined)}. As a semantic basis for the propositional part of a corresponding nondeterministic three-valued logic we study the notion of a truth-function over {T, F, U} which is computable by a nondeterministic evaluation procedure. The main result is that these truth-functions are precisely the functions satisfying four basic properties, called \( \subseteq \) -isotonic, \( \subseteq \) ?-isotonic, hereditarily guarded, and hereditarily guard-using, and that a function satisfies these properties iff it is explicitly definable (in a certain normal form) from “if..then..else..fi”, binary choice, and constants.  相似文献   
62.
This study aimed to clarify how manifestations and acquisition relate to diagnostic categories of dental fear in a population of self-referred dental fear patients, since diagnostic criteria specifically related to dental fear have not been validated. DSM III-R diagnostic criteria for phobias were used to compare with four existing dental fear diagnostic categories, referred to as the Seattle system. Subjects were 208 persons with dental fear who were telephone interviewed, of whom a subsample of 155 responded to a mailed Dental Anxiety Scale (DAS), State-Trait Anxiety Inventory and a modified FSS-II Geer Fear Scale (GFS). Personal interviews and a Dental Beliefs Scale of perceived trust and social interaction with dentists were also used to evaluate a subsample of 80 patients selected by sex and high dental fear. Results showed that the majority of the 80 patients (66%), suffered from social embarrassment about their dental fear problem and their inability to do something about it. The largest cause of their fear (84%) was reported to be traumatic dental experiences, especially in childhood (70%). A minority of patients (16%) could not isolate traumatic experiences and had a history of general fearfulness or anxiety. Analysis of GFS data for the 155 subjects showed that fear of snakes and injuries were highest among women; heights and injections among men. Fear of blood was rarely reported. Spearman correlations between GFS individual items and DAS scores indicated functional independence between dental fear and common fears such as blood, injections and enclosures in most cases. Only in specific types of dental fear did these results support Rachman and Lopatka's contention that fears are thought to summate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
63.
Summary In an experiment modelled upon the classical paradigm on release from proactive interference (PI), subjects were required to remember series of actions they had performed (e.g., roll the ball, fold the paper). The objects involved in these subject-performed tasks (SPTs) served as a basis for build-up and release of PI. The objects used in the first few trials of the experiment belonged to the same class (e.g., parts of the body), causing a build up of PI. A shift to a different class of objects (e.g., kitchen utensils) along four different dimensions (taxonomic category, weight, color, and size) was introduced to cause a release of PI. On the basis of PI-release experiments with words it was expected that shifts in taxonomic category would result in a greater release than shifts within any of the physical dimensions. However, the results revealed that the amount of PI release was, in general, larger than expected, and essentially the same for all four dimensions investigated. The results are discussed in terms of the nature of the memory representation of SPTs, and with regard to possible processing differences between SPTs and verbal information. In addition, methodological suggestions for furthering the understanding of the encoding and storage of action events are advanced.  相似文献   
64.
In this paper three questions concerning quality of life in medicine and health care are analysed and discussed: the motives for measuring the quality of life, the methods used in assessing it, and the definition of the concept. The purposes of the study are to find an ethically acceptable motive for measuring the quality of life; to identify the methodological advantages and disadvantages of the most prevalent current methods of measurement; and to present an approach towards measuring and defining the quality of life which evades the difficulties encountered and discussed. The analysis comprises measurements both in the clinical situation concerning individual patients and in research concerning whole populations. Three motives are found for evaluating the quality of human life: allocation of scarce medical resources, facilitating clinical decision making, and assisting patients towards autonomous decision making. It is argued that the third alternative is the only one which does not evoke ethical problems. As for the methods of evaluation, several prevalent alternatives are presented, ranging from scales of physical performance to more subtle psychological questionnaires. Clinical questionnaires are found to fail to provide a scientific foundation for universally measuring the quality of life. Finally, the question of definition is tackled. The classical distinction between need-based and want-based theories of human happiness is presented and discussed. The view is introduced and defended that neither of these approaches can be universally preferred to the other. The difficulty with the need approach is that it denies the subjective aspects of human life; whereas the problem of the want approach is that it tends to ignore some of the objective realities of the human existence. In conclusion, it is argued that the choice of methods as well as definitions should be left to the competent patients themselves — who are entitled, if they so wish, to surrender the judgement to the medical personnel. Technical factors as well as the requirements of respect for autonomy and informed consent support this conclusion.  相似文献   
65.
Subjects (N = 32) were asked to synchronize a motor response with tones in auditory patterns. These patterns were created from six tones and six intertone intervals of equal duration. The pitch of the first tone differed from the others. It was found that subjects used three types of timing in their motor response: (1) the first intertone interval was prolonged and the second interval was shortened, (2) the second intertone interval was prolonged and the first interval was shortened, and/or (3) the first interval and the second interval were of approximately the same length. The prolongation of the fifth interval was observed during all three types of timing. The results are explained using the concept of suprasegmental control of timing, which explains a prolongation of intervals at critical control point of the patterns. The occurrence of three different strategies of timing is discussed in connection with similar principles in musical performance.  相似文献   
66.
Unreliable probabilities,risk taking,and decision making   总被引:7,自引:0,他引:7  
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67.
Summary An experiment was presented to test a functionalistic interpretation of the modality effect. This shows a superior recall performance for auditorily as opposed to visually presented verbal information. A total of 60 subjects were presented with mixed-mode (auditory-visual words), mixed-language (Swedish-English words), or mixed-category (category-unrelated words) lists, and were asked to recall the words of each list in any preferred order. The degree of organization according to modality, language, or category and the recall performance were measured. Organization by modality was significantly higher than organization by language or category as predicted by the functionalistic view proposed. The recall performance obtained for auditory and visual words differed in a way predicted by the functionalistic view.  相似文献   
68.
The relationship between perceived physiological arousal and actual heart-rate reactions was studied in two behavioral test situations. The subjects were 70 phobic patients (34 social phobics and 36 claustrophobics) who were given the general form of the Autonomic Perception Questionnaire about 1 month before the respective behavioral test and the specific form immediately after the test. The results showed significant correlations between APQ and actual heart rate for the social phobics, while the picture was more complicated for the claustrophobics. The implications of these results are discussed.This research was supported by Grant 05452 from the Swedish Medical Research Council.  相似文献   
69.
The general psychophysical differential equation, dy/dx = W2(y)/W1(x), with the solution y = f(x), where x and y are subjective variables and W1 and W2 their subjective Weber functions, is (a) compared with a corresponding functional equation, and (b) studied from a stochastic point of view by error calculus, Methods for evaluating and handling divergences are proposed and illustrated for a number of combinations of Weber functions. It is shown that either the differential: and the functional equations have the same solution or the difference between the solutions is negligible compared to empirical scatter. The error calculus gives the same result: either no error at all or a negligible one.  相似文献   
70.
This article deals with relations between mental motor evoking capacity (motority, Putnoky, 1975a, b) and the sensory and affective connotations, as well as certain denotations, of words. Sensory connotation is indexed by degree of visual auditory, and tactual imagery, as assessed on a 7-point scale, while affective connotation is indexed by the usual three factors tapped by the semantic differential. The aspect of denotation used here is the abstractness value of words, also based on rating by scales. The general conclusions about motority are as follows: (1) the finding that its sensory connotations are mainly via theauditory modality of imagery, and especially in correlation with abstract words, suggests that it has a specific function that may have originated in the processing of heard language; (2) it correlates with thepotency andactivity factors of affective connotation, which suggests the existence of a nonspecific function or component in it; (3) correlations with abstractness reflect that motority must have a denotative function or component, especially in case of abstract verbal stimuli. On the basis of the results, motority is supposed to play a regulative role at higher levels of the organization of word meaning in particular.Computation of SD data was carried out under the direction and according to the programming of Professor William H. May in the Center for Comparative Psycholinguistics (Director: Charles E. Osgood), University of Illinois, Urbana-Champaign, with support provided by the National Institute of Mental Health (NIMH 07705) and National Science Foundation (NSF GS 360 and 2012-X).  相似文献   
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