首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   477篇
  免费   9篇
  486篇
  2021年   6篇
  2020年   4篇
  2019年   10篇
  2018年   13篇
  2017年   14篇
  2016年   13篇
  2015年   15篇
  2014年   8篇
  2013年   65篇
  2012年   17篇
  2011年   23篇
  2010年   11篇
  2009年   13篇
  2008年   23篇
  2007年   15篇
  2006年   13篇
  2005年   16篇
  2004年   7篇
  2003年   10篇
  2002年   18篇
  2001年   14篇
  2000年   20篇
  1999年   9篇
  1998年   6篇
  1997年   8篇
  1996年   4篇
  1994年   3篇
  1992年   8篇
  1991年   9篇
  1990年   5篇
  1989年   12篇
  1988年   7篇
  1987年   4篇
  1986年   5篇
  1985年   6篇
  1984年   4篇
  1983年   4篇
  1982年   2篇
  1980年   3篇
  1977年   2篇
  1976年   2篇
  1975年   5篇
  1974年   2篇
  1973年   2篇
  1972年   3篇
  1969年   3篇
  1968年   2篇
  1967年   2篇
  1966年   2篇
  1965年   2篇
排序方式: 共有486条查询结果,搜索用时 0 毫秒
121.
    
Attention and social functioning and their interrelationships have not been routinely examined in children with early brain insult (EBI). This study aimed to describe attention and social functioning in children with two types of EBI: malformations of cortical development (MCD) and stroke. Children diagnosed with MCD (n?=?14, 6 males) or stroke (n?=?14, 8 males) aged 8 to 14 years (M?=?12 years 11 months) completed neuropsychological assessments to examine attention processes. Primary caregivers completed a questionnaire to assess executive components of children's attention and teachers completed a questionnaire to measure children's social functioning. Brain scans (MRI or CT) were coded by a pediatric neuroradiologist. Higher rates of impairments in attention and social function were found in children with EBI compared with normative expectations. Children with MCD experienced more global and clinically significant levels of impairment than children with stroke; though impairments were present in both groups. A strong association between executive components of attention and social function was observed. In addition, complex attention processes were associated with social function. The findings emphasize the reciprocity between attention, behavior and social outcomes, and the vulnerability of social function following EBI.  相似文献   
122.
It is important to study communication processes in families where members are undergoing testing for genetic conditions because the information received from such testing is crucial not just to the individual concerned but also to other members of the biological family. This topic has received little research attention, in part because of the complexities of methodology required. In this paper we present the development of a method specifically designed for the examination of the content and process of communication of genetic information in families. The method aims to maximize ecological validity as far as is possible. We describe how participants and other family members are recruited and how data were collected. We outline three main data analytic strategies: a graphic to show how genetic information changes as it flows from clinic and through the family, an intensive qualitative analysis of the meaning and impact of the genetic information to different family members, and an informative genogram which plots key family dynamics. This method will be illustrated in relation to a study of ten family-groups where one individual has been found to carry a genetic mutation predisposing them to hereditary breast and ovarian cancer.  相似文献   
123.
OBJECTIVES: Within the socio-ecologic framework, diet and physical activity are influenced by individual, interpersonal, organizational, community, and public policy factors. A basic principle underlying this framework is that environments can influence an individual's behavior. However, in the vast majority of cross-sectional and even the few longitudinal studies of this relationship, the question of whether individuals select their area of residence based on physical activity-related amenities is ignored. In this paper, we address a critical methodological issue: self-selection of residential location, which is generally not accounted for, and can significantly compromise research on the relationship between environmental factors and physical activity behaviors. METHOD: We define and discuss the problem of residential self-selection in the study of neighborhood influences on health and health behavior, review methods used to control for residential self-selection in the literature, and present our strategy for addressing this potentially important source of bias. CONCLUSION: Existing research has built our understanding of residential self-selection bias, but important gaps remain. Our strategy uses data from a longitudinal cohort study linked to contemporaneous environmental measures to create a multi-equation model system to simultaneously estimate residential choice, environmental influences on physical activity, and downstream health outcomes such as obesity and clinical cardiovascular disease risk factor measures.  相似文献   
124.
This investigation evaluated the construct validity of the Psychopathic Personality Inventory (PPI; Lilienfeld & Andrews, 1996), a self-report measure designed to assess psychopathy. One hundred and two incarcerated females were administered the Kaufman Brief Intelligence Test (K-BIT), an oral alcohol and drug screening measure, a demographic interview, the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), the Psychopathy Checklist-Revised (PCL-R), and the PPI. There were significant correlations among the PPI, MMPI-2 scales, and the PCL-R. In addition, the correlations between the PPI and the separate PCL-R factors were not significantly different from each other, indicating that the PPI is assessing both facets of the psychopathy construct to some extent. A high correlation between the PPI and the DSM-IV criteria, which assesses adult antisocial behaviors, revealed adequate concurrent validity. Nonsignificant or negligible correlations between the PPI and the MMPI-2 scales provided some support for discriminant validity. The results are discussed with respect to the clinical and forensic utility of the PPI, the limitations of the study, and the need for further research.  相似文献   
125.
Genetic testing for BRCA1/2 mutations associated with hereditary breast and ovarian cancer reveals significant risk information about one's chances of developing cancer. It is important to study communication processes in families where members are undergoing genetic testing because the information received is crucial not just to the individual concerned but also to other members of the biological family. This study investigates family communication of BRCA1/2 test results from both the informants' and recipients' perspectives. A total of 10 female patients and 22 of their relatives were interviewed. Patients' and their relatives described feelings of responsibility for sharing genetic information within the family to enable others to reduce their risks of developing cancer. However, there were limits to an individuals' responsibility once key family members had been informed, who then had to take responsibility for continuing dissemination of information. Whilst there was an implicit responsibility to inform the family of a mutation, information was edited or withheld in the best interest of relatives, dependent upon their perceived emotional readiness, resilience and current life stage and circumstances. The pre-existing family culture and the impact previous cancer diagnoses had upon the family also influenced the process of communication. Findings are discussed in relation to extant literature and implications for clinical practice are considered.  相似文献   
126.
The present study reports two experiments in which a total of 20 participants without prior flight experience practiced the final approach phase in a fixed-base simulator. All participants received self-controlled concurrent feedback during 180 practice trials. Experiment 1 shows that participants learn more quickly under variable practice conditions than under constant practice conditions. This finding is attributed to the education of attention to the more useful informational variables: Variability of practice reduces the usefulness of initially used informational variables, which leads to a quicker change in variable use, and hence to a larger improvement in performance. In the practice phase of Experiment 2 variability was selectively applied to some experimental factors but not to others. Participants tended to converge toward the variables that were useful in the specific conditions that they encountered during practice. This indicates that an explanation for variability of practice effects in terms of the education of attention is a useful alternative to traditional explanations based on the notion of the generalized motor program and to explanations based on the notions of noise and local minima.  相似文献   
127.
128.
Although Norway rats are naturally gregarious, males typically live alone at some point during adulthood. Different social ecologies often require different learning strategies and also modulate response to stressors and gonadal development. To measure effects of the social environment on the interaction between cognition and emotion during aging, we focused on a natural learning context and devised the sectored foraging field, a progressively difficult spatial navigation task. Here, we describe how this apparatus and protocol permits multiple learning strategies in a minimally stressful environment, enabling finely graded analyses of cognition and emotionality. Male Sprague-Dawley rats living alone throughout adulthood adopted a sex-typic discernible spatial strategy. In contrast, males housed in group contexts utilized an algorithmic kinesthetic strategy, repeating the same motor action until they found food. Removal of food and distal, but not local cues, elicited anxious alertness, particularly in group-housed males. Cognitive performance of group-housed rats subsequent to food and cue removal was significantly impaired, yet enhanced in isolates.  相似文献   
129.
Corticobasal degeneration (CBD) is a progressive disorder characterized by both cortical and basal ganglia dysfunction such as asymmetrical apraxia, and akinetic rigidity, involuntary movements, and cortical sensory loss. Although apraxia is a key finding for the differential diagnosis of CBD, it has not been determined whether the features of apraxia seen in subjects with CBD are similar to those features exhibited by subjects with left-hemisphere damage from stroke. Therefore, for both clinical purposes and in order to better understand the brain mechanisms that lead to apraxia in CBD, we studied praxis in a patient with CBD and compared him to patients who are apraxic from left-parietal strokes. We used three-dimensional movement analyses to compare the features of apraxic movement. This subject with CBD was a dentist whose initial complaint had been that he "forgot" how to use his tools in the mouths of his patients. Analyses were performed on the trajectories made when using a knife to actually slice bread, and when repetitively gesturing slicing made to verbal command. Movements of the left hand, wrist, elbow, and shoulder were digitized in 3-D space. Although the CBD subject was clearly apraxic, the features of his apraxia differed markedly from those of the subjects with lesions in the left parietal lobe. For movements to command, the CBD subject showed joint coordination deficits, but his wrist trajectories were produced in the appropriate spatial plane, were correctly restricted to a single plane, and, like control subjects, were linear in path shape. However, when he was actually manipulating the tool and object, all of these aspects of his trajectories became impaired. In contrast, the deficits of the apraxic subjects with left-parietal damage were most pronounced to verbal command with their movements improving slightly although remaining impaired during actual tool and object manipulation. Unlike patients with parietal strokes, patients with CBD have degeneration in several systems and perhaps deficits in these other areas may account for the differences in praxic behavior.  相似文献   
130.
Tachistoscopic examinations, determinations of reaction times after visual stimuli, and latency measurements of visual evoked potentials require well-defined and often very fast display buildup on the monitor. Display buildup takes at least 14 msec when a VGA board is used in standard video modes. This time can be reduced to 4 msec or less by reprogramming some registers of the display adapter.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号