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31.
A. Giovagnoni E. Paci Paola Ercolani B. Kiefer P. Santino A. Piga 《Magma (New York, N.Y.)》1995,3(3-4):143-150
The aim of this study was to compare conventional spin-echo (CSE)T
2-weighted (T2W) images with turbo spin-echo (TSE) T2W pulse sequences in their ability to detect focal liver lesions. Seventy-eight consecutive patients with focal liver lesions were entered into this study. All patients were imaged using the gradient-echo (GE) sequence with the breath-hold technique forT
1-weighted (T1W) images, and CSE and TSE sequences for T2W images. Qualitative evaluation included lesion detection (number of lesions detected) and conspicuity (extent of visualization of lesional borders); quantitative evaluation included the signal-to-noise (S/N) ratio and the contrast-to-noise (C/N) ratio. TSE showed the best performance in terms of lesion detection; however, the difference between TSE and CSE was significant only in the case of benign cysts (p<0.01). Conspicuity was higher with TSE and CSE, and lower with GE. The S/N and C/N ratios of the two T2W sequences were also comparable, and better than those of GE. However, the combined use of GE and TSE resulted in improved lesion detection. The results show that, because the acquisition time is greatly reduced with TSE sequences, these should be considered as first-line approach to magnetic resonance imaging of the liver for the study of focal lesions. 相似文献
32.
Hanssen M.; Krabbendam L.; Vollema M.; Delespaul P.; Van Os J. 《Canadian Metallurgical Quarterly》2006,115(1):5
It is unknown to what degree dimensions of schizotypy (subclinical psychosis) show independent, family-specific variation in the general population. Psychologists administered the Community Assessment of Psychic Experiences, the Structured Interview for Schizotypy-Revised (SIS-R), and the Brief Psychiatric Rating Scale to 257 subjects pertaining to 82 general population families. All 3 instruments showed family-specific variation for positive and negative subclinical psychosis dimensions with between-families proportions of total variance between 10% and 40%. However, only the SIS-R showed family-specific variation of the negative dimension independent of its correlation with the positive dimension. The positive dimension of subclinical psychosis shows familial-specific variation in samples unselected for psychiatric disorder, suggesting dimensional liability in the population. The SIS-R additionally captures family-specific variation in the negative domain. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Snell-Johns Jessica; Mendez Julia L.; Smith Bradley H. 《Canadian Metallurgical Quarterly》2004,18(1):19
Various definitions exist for what constitutes family therapy. In this article, we consider family therapy to encompass any intervention that targets family interactions and conceptualizes problems as existing beyond individual clients. Numerous individual studies and several quantitative reviews have established family therapy as an effective treatment modality and the treatment of choice for many disorders. However, critiques of existing service provision highlight the unfortunate fact that numerous barriers to treatment exist at multiple levels of the broader ecology, preventing many families from benefiting from these services. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
This article outlines an approach to treatment of sexually abused children with dissociative symptoms. Dissociated self-states are seen as competing interpersonal approaches to handling the many emotional sequela of abuse, including anger, fear, and regressive needs. Parents' responses to their sexually abused children, complicated by guilt and their own histories of trauma, can promote dissociative coping in the children as they have difficulty processing their own real feelings of anger, fear, and responsibility. Children and parents may alternatively take victimizer, victim, and rescuer roles, thus mutually reinforcing a dissociative style of coping with these events. This article illustrates how sensitivity to these family dynamics, along with a problem-solving approach to the child's symptoms, can treat dissociative psychopathology in these children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Co-evolution as a computational and cognitive model of design 总被引:6,自引:0,他引:6
Co-evolutionary design has been developed as a computational model that assumes two parallel search spaces: the problem space
and the solution space. The design process iteratively searches each space using the other space as the basis for a fitness
function when evaluating the alternatives. Co-evolutionary design can also be developed as a cognitive model of design by
characterizing the way in which designers iteratively search for a design solution, making revisions to the problem specification.
This paper presents the computational model of co-evolutionary design and then describes a protocol study of human designers
looking for evidence of co-evolution of problem specifications and design solutions. The study shows that co-evolutionary
design is a good cognitive model of design and highlights the similarities and differences between the computational model
and the cognitive model. The results show that the two kinds of co-evolutionary design complement each other, having strengths
in different aspects of the design process.
Electronic Publication 相似文献
36.
37.
《Canadian Metallurgical Quarterly》2003,39(3):581
The role of attention processes as possible mediators between family environment and school readiness was analyzed with data from 1,002 children and their families. Data on children's sustained attention, impulsivity, and school readiness (i.e., cognitive, achievement, language, and social development) were obtained at 54 months of age, and quality of the family environment was assessed throughout the first 54 months. Mediation tests showed that children's sustained attention partially accounted for the link between family environment and achievement and language outcomes. Impulsivity partially accounted for the link between family environment and achievement, social competence, and externalizing behaviors. The roles of sustained attention and of inhibition of impulsive responding in the relation between family characteristics and school readiness are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
“Symmetric materials” devices, where both electrodes are made of the same electrochromic materials, allow the in situ study of side reactions. Each transferred charge that is not used for the expected electrochromic reaction will cause a colour change in the whole symmetric device. Two electrochromic materials, WO3 and IrO2, are successively used to show how to obtain information about side reactions such as faradaic efficiency, reversibility and potential limits from the symmetric experiment. This in situ approach with a polymer electrolyte shows significant differences compared to results obtained with studies in aqueous electrolytes. 相似文献
39.
Hebb's principal theoretical propositions, the cell assembly and the nature of synaptic change, were generated at a time when the focus of work in behavioural neuroscience was directed at understanding issues such as the principles governing the behaviour of animals in neuropsychological studies of learning and memory and the role of drives in the control of behaviours like sex and feeding and drinking. It was not until attention shifted to understanding the neural underpinnings of learning and memory that Hebb's propositions had an impact on behavioural neuroscience as they provided a simple, and testable, mechanism for synaptic plasticity observed both in learning and in other forms of experience-dependent neural change. But much of the field remains interested in other issues such as sensation and perception, motivation, attention, and so on, and to date, Hebb's propositions have had little impact. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Stewart Abigail J.; Antonucci Toni C.; Veroff Joanne B. 《Canadian Metallurgical Quarterly》2003,58(5):405
Presents an obituary for Elizabeth Douvan (1926-2002). Douvan was a pioneer in the study of changing gender, work, and family roles; personal values; and well-being in the second half of the 20th century. Through her research, she contributed to the interdisciplinary fields of social psychology and women's studies while building and strengthening institutions that remain committed to the same mission. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献