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991.
Conclusion The world contains not only causes and effects, but also causal relations holding between causes and effects. Because causal relations enter into the structure of the world, their presence has various modal and probabilistic consequences. Causation and necessary and sufficient conditions do often go hand in hand. Causation, however, is a robust ingredient within the world itself, whereas modalities and probabilities supervene on the nature of the world as a whole, and on the resulting relations between one possible world and others. Some modalities, therefore, are essentially causal; but causation is not essentially modal.19  相似文献   
992.
993.
Risk perceptions and participation in colorectal cancer screening   总被引:4,自引:0,他引:4  
Compared individuals at high versus average risk for colorectal cancer (CRC) with respect to factors they cited as affecting their risk of developing CRC. We also examined the relationship of these risk-factor perceptions to perceived susceptibility and participation in a CRC screening test. All individuals in the high-risk group were informed that, as a sibling of someone with CRC, they were more likely to get this cancer themselves. We found minimal differences among siblings with respect to perceived susceptibility. Further, although high-risk siblings were more likely to participate in screening, only 20.2% cited heredity as a risk-increasing factor, and, among these siblings, there was no relationship between screening participation and the citation of any specific risk factors, including heredity. These findings demonstrate the need for more research examining how high-risk individuals process risk-relevant information and the effect of this information on health behavior.  相似文献   
994.
Compared four treatment conditions to test their ability to enhance compliance with vascular access cleansing (VAC) procedures in a group of 56 hemodialysis patients. The conditions were patient education, behavioral management with monetary incentive, patient education/behavioral management, and attention control. Behavioral observers rated VAC behavior at pretreatment, posttreatment 1-month follow-up, and 1-year follow-up. Knowledge of VAC procedures was also assessed via a questionnaire at pretreatment and posttreatment. Data were analyzed using repeated-measures multivariate analyses of variance. Results indicated that the patients in the education/behavioral, behavioral, and education groups gave significantly more correct answers on our VAC knowledge questionnaires at posttreatment than did patients in the attention control group. Further, patients in the education/behavioral and behavioral groups completed significantly more VAC steps at posttreatment and 1-month follow-up than did patients in the education group and in the attention control group. Differences were not maintained at 1-year follow-up, although more than 50% of the patients were lost to follow-up. Implications of the present findings for behavioral and educational interventions are discussed.  相似文献   
995.
Saccadic reaction times of dyslexic and age-matched normal subjects   总被引:2,自引:0,他引:2  
B Fischer  H Weber 《Perception》1990,19(6):805-818
Saccadic reaction times (SRT) were measured in a simple task: subjects had to make saccades from a central fixation point to peripheral targets, which appeared randomly 4 deg to the left or to the right. In the first test the fixation point went off before the target appeared (gap trials); in the second test it remained on the screen (overlap trials). The distribution of SRTs for trained normal adults (N = 4), untrained normal adults (N = 11), untrained normal children (aged 9-11 years, N = 9), untrained normal teenagers (aged 15-17 years, N = 8), dyslexic children (aged 9-11 years, N = 15), and dyslexic teenagers (aged 15-17 years, N = 5) were compared, with special emphasis on the number of express saccades, ie saccades with extremely short reaction times (100-120 ms, under the present conditions). In normal adults with the gap paradigm, the distribution of reaction times typically exhibits two or three modes (express saccades, fast regular saccades, and very few slow regular saccades), whereas in the overlap paradigm only one or two modes (few fast regular saccades and many slow regular saccades) are obtained. On average, normal children produce more express saccades than naive normal adults. Dyslexic children produce more express saccades than the normal age-matched controls. Among the dyslexic children, four different types of abnormalities in their reaction times were encountered. The group of dyslexic teenagers was characterized by a larger number of express saccades at the expense of fast regular saccades in gap trials and by fewer express saccades and fewer fast regular saccades in overlap trials when compared to the age-matched control group. It is concluded that the abnormal patterns of saccadic reaction times reflect defects in the system of visual attention and/or in its control over the oculomotor system, rather than indicating a defect in the oculomotor system itself. In this context, symptoms of dyslexia appear as a combination of attentional deficits and irregular timing of saccadic eye movements.  相似文献   
996.
Sex differences in children's time use   总被引:1,自引:0,他引:1  
A sample of children (410 on a school day and 347 on a non-school day) was examined to determine differences in time spent in household work, leisure activities, school, paid work, personal care, and sleep by males and females. Males spent more time in leisure activities and less time in household work and personal care than females. Differences in time allocation appeared to be in accordance with traditional male-female roles. These patterns were established at early ages.  相似文献   
997.
998.
Family rituals express patterned, repeated, symbolic communication that is ordered, evocative, socially meaningful, and directly impacts upon family functioning. Seasonal celebrations, rites of passage, family traditions, and patterned family interactions serve to organize the family, mediate individual expectations, regulate family subsystems, and facilitate change. Clergy and psychotherapists can use an understanding of family rituals to better understand individuals in their family context, promote change through prescribing rituals, and help clients create new, healing rituals.  相似文献   
999.
It was hypothesized that older widows (N=309) who had been care givers to their husbands would have undertaken a greater number of household responsibilities than had women who had not been care givers. Findings indicated that, prior to the husband's death, more traditionally male and more traditionally female tasks were performed by the care-giving wives (n=158). This was particularly true in the case of Alzheimer's care givers (n=21). More importantly, widows' present feelings of competence were related to undertaking household responsibilities, with those who had been care givers expressing significantly higher levels of competence.  相似文献   
1000.
Interpersonal loss and self-mutilation   总被引:1,自引:0,他引:1  
Self-mutilation was hypothesized to increase in frequency during periods of interpersonal loss in a treatment program for seriously disturbed adolescents. The study examined changes in the frequency of acts of self-mutilation, aggression, and running away for 32 teenagers who experienced interpersonal loss when staff members left employment. Data were collected for a 4-year period. Statistical findings indicated that the frequency of self-mutilation increased significantly during the time period of anticipated loss, 2 weeks prior to staff terminations. There was no significant increase in the frequency of self-mutilation immediately following the staff terminations. Also, there was no significant change in the rates of aggression or running away either before or after the loss events. It was concluded that the time of anticipated loss was the period of highest risk for these adolescents in terms of self-mutilative behavior.  相似文献   
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