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Sixteen German-English bilinguals were studied in a sleep laboratory for four nonconsecutive nights each. Half were native English speakers living in Zürich, and half native German speakers living in Atlanta. Presleep thought samples were solicited each evening and REM dream reports each night; subjects judged the waking appropriateness of their imagined speech and language phenomena, and also identified waking sources of their dream imagery, the following mornings. Incidences of dreaming and of speech therein generally were similar to those of monolinguals. Whether sessions were conducted in German (two nights) or English (two nights) did directly influence language selection in subjects' dreams. Judged appropriateness of language selection to imagined events was very high for thought samples, and high for REM dreams. Sources for thought samples were generally consonant with the language dominant at study site; for REM dreams this relationship was considerably weaker. Judged waking appropriateness to imagined situations was more strongly related to language selection than was the language reference of the supposed sources of those situations.  相似文献   
13.
Previous experiments have shown that the procedure of questioning subjects retrospectively about the input and output status of information (input and output monitoring) is a useful method for assessing the awareness states of subjects during implicit and explicit memory tasks. The main purpose of the present study was to investigate whether the previous findings could be extended to other implicit and explicit memory tasks. We were especially interested in whether differences in input- and output-monitoring performance can be observed when both the implicit and explicit memory tasks are conceptual ones. In a final test phase, the target items from the study phase and new distractor items were presented. In a recognition-like situation, subjects had to decide whether an item had been presented in the study phase (input status), as well as whether they had produced the item in the memory-test phase (output status). In all three experiments judgments about the input status - but only for those items that had been produced in the implicit or in the explicit memory test - were more precise after explicit than after implicit memory testings. This finding was not influenced by the distinction between perceptual and conceptual-memory tasks (Exp. 1), and was obtained under conditions in which the implicit and the explicit memory tasks were both conceptual and differed only in test instructions (Exps. 2 and 3). These results suggest that not only subjects performing a perceptual test of implicit memory, but also subjects in a conceptual implicit test were less aware of using information from a previous study episode than subjects who received memory instructions. It is concluded that requiring judgments about the input status of information is a good method for assessing subjects test awareness and is preferable to the use of a questionnaire (Exp. 3). In contrast, in all three experiments no differences were found with the output-monitoring measure between implicit and explicit test conditions.  相似文献   
14.
Per-erik Malmnäs 《Synthese》1994,99(2):233-249
It is argued that existing axiomatic theories of utility do not provide the utility principle or the principle of maximising expected utility with a formal justification. It is also argued that these theories only put mild constraints on a decision-maker in a decision-context. Finally, it is argued that the prospects are not particularly bright for finding formal non-circular arguments for the utility principle that do not rely on the law of large numbers.  相似文献   
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In a dichotic listening situation stimuli were presented one at a time and at random to either ear of the subject at constant inter-stimulus intervals of 800 msec. The subject's task was to detect and count occasional slightly different stimuli in one ear. In Experiment 1, these ‘signal’ stimuli were slightly louder, and in Experiment 2 they had a slightly higher pitch, than the much more frequent, ‘standard’, stimuli. In both experiments signals occured randomly at either ear. Separate evoked potentials from three different locations were recorded for each of the four kinds of stimuli (attended signals, unattended signals, attended standards, unattended standards). Contrary to Hillyard et al. (1973), no early (N1 component) evoked-potential enhancement was observed to stimuli to the attended ear as compared with those to the unattended ear, but there was a later negative shift superimposed on potentials elicited by the former stimuli. This negative shift was considered identical to the N1 enhancement of Hillyard and his colleagues which in the present study was forced, by the longer inter-stimulus interval used, to demonstrate temporal dissociation with the N1 component. The ‘Hillyard effect’ was, consequently, explained as being caused by a superimposition of a CNV kind of negative shift on the evoked potential to the attended stimuli rather than by a growth of the ‘real’ N1 component of the evoked potential.  相似文献   
17.
In this paper a propositional logic of viewpoints is presented. The language of this logic consists of the usual modal operatorsL (of necessity) andM (of possibility) as well as of two new operatorsA andR. The intuitive interpretations ofA andR are “from all viewpoints” and “from some viewpoint”, respectively. Semantically the language is interpreted by using Kripke models augmented with sets of “viewpoints” and with a new alternativeness relation for the operatorA. Truth values of formulas are evaluated with respect to a world and a viewpoint. Various axiomatizations of the logic of viewpoints are presented and proved complete. Finally, some applications are given.  相似文献   
18.
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   
19.
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   
20.
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   
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