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951.
952.
The purpose of the present study was to investigate the extent to which performance of a complex cognitive task of a type resembling that encountered in everyday life is maintained through adulthood. A total of 80 subjects participated; 20 in their thirties, 20 in their fifties, 20 in their sixties, and 20 in their seventies. Subjects were asked to make preference judgments with respect to 32 pocket-size notebooks of a sort they might encounter as consumers in a stationery or variety store. Independently, they were also asked to express their preferences with respect to each of the four dimensions on which the notebooks varied. With only minor differences across age groups, most subjects demonstrated the ability to integrate their individual dimension preferences into a complex preference judgment of an object embodying those dimensions, in a logically consistent manner.  相似文献   
953.
954.
In choice reaction time (RT) tasks, college students verified the truth of displays expressing spatial relations between two objects. The relations werelocational (A is left of B) ororientational (A and B are horizontal). The objects were names of states in the United States, symbols, or letter arrays. The objects were memorized prior to the display (states and letters) or were presented as part of the display (symbols and letters). In the location tasks with both states and symbols, locatives were spatial (right, left, above, below) or compass (north, south, east, west). Distance between states was also varied. When location was judged, horizontally aligned stimuli resulted in slower responses than vertically aligned stimuli, independently of materials and locative set. Reaction time was inversely related to distance. When orientation was judged, responses to horizontal pairs of states were slower than responses to vertical pairs of states, responses to horizontal pairs of letters were faster than responses to vertical pairs, and RT did not depend upon the orientation of symbols. This pattern of results suggests that orientational judgments are influenced by type of materials and the entext to which the material has been encoded (i.e., memorized). Locational judgments reflect a potent source of difficulty not present in orientation tasks, namely, telling left from right. Alternative explanations of the right-left effect are discussed.  相似文献   
955.
Fuzzy intuitionistic quantum logics (called also Brouwer-Zadeh logics) represent to non standard version of quantum logic where the connective not is split into two different negation: a fuzzy-like negation that gives rise to a paraconsistent behavior and an intuitionistic-like negation. A completeness theorem for a particular form of Brouwer-Zadeh logic (BZL 3) is proved. A phisical interpretation of these logics can be constructed in the framework of the unsharp approach to quantum theory.  相似文献   
956.
Instructive feedback involves presenting extra, non-target stimuli in the consequent events for children's responses. Two methods of presenting instructive feedback during direct instruction were compared. These methods involved presenting two extra stimuli on all trials, and presenting the two extra stimuli separately on alternating trials. Preschool students were taught coin combinations using a constant time delay procedure with instructive feedback stimuli added to both praise and correction statements. An adapted alternating treatments design was used to evaluate the two methods of presenting instructive feedback. The students were assessed to determine the extent to which instructive feedback stimuli were learned. The results indicate that students learned some of the instructive feedback stimuli and no consistent differences in the effectiveness of the two presentation methods were noted. Further, relationships between the two instructive feedback stimuli appeared to be established. Implications for instruction and future research are discussed.  相似文献   
957.
Internal and external validity problems permeate all intervention studies but are accentuated in primary preventive intervention research, particularly when studies target or recruit individuals based on their risk for psychopathology. Since many people who are at risk do not yet experience distress, they may not perceive the need for intervention. Recruitment tactics based on explaining extent of risk are unlikely to be persuasive and may have negative consequences. If respondents are not motivated to participate, a small or biased subset of the target population will participate in the intervention. Bias is of special concern when those enrolled represent only part of the continuum of risk. Selective enrollment may compromise both internal validity (the interpretation of the research results) and external validity (the generalizability of the findings) of intervention trials in primary prevention. This article discusses the effects of partial enrollment and the resultant bias. It suggests several strategies for increasing the enrollment of the target population and examines some of their ethical ramifications. It also stresses the importance of collecting systematic data documenting how the participants in the intervention differ from the target group as a whole.  相似文献   
958.
The relationship between personality characteristics, daily stressors, and means of coping were studied in a 12-person Soviet-American expedition ateamconsisting of Caucasian and Eskimo men and women. The members scored relatively high on scales measuring well-being, achievement orientation, and traditionalism and scored relatively low on stress reactivity. The use of social support as a coping mechanism was positively related to high stress reactivity, control, and negative emotionality and negatively related to well-being. Negative emotionality was related to ratings of daily intrapersonal stressor. Discussion centered on the function of social support in an extreme, task-focused situation and the relationship of social support coping in this particular type of situation to maladaptive personality characteristics.  相似文献   
959.
Pilot studies indicate that the workplace is a successful site for the implementation of smoking cessation programs (Jason et al., 1987a; 1987b;). Cessation efforts using monetary incentives have had yielded increased success in abstinence (Kleges & Cigrang, 1989). This article provides an overview of previous efforts at worksite cessation programs and outlines a new study that will use self help manuals, incentives, and group support sessions in a multilevel intervention in an attempt to identify successful components of worksite programs. The four year project will attempt to develop a comprehensive worksite program that is capable of being implemented by individual companies. To this end, sixty corporations will receive one of three programs and a week long television newscast on WGN-TV will be aired to accompany the interventions. An overview of the project is presented.The authors appreciate the financial support from the National Heart, Lung and Blood Institute (Grant Number 42987).  相似文献   
960.
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