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Penelope S. Myers 《Aphasiology》2013,27(10-11):913-918
Research and clinical efforts aimed at understanding and improving the communication impairments associated with acquired right hemisphere damage (RHD) are hampered by lack of a formal definition or label. This paper addresses that issue in light of the recent proposal by Joanette and Anslado (1999a, b) that RHD communication disorders be called "Pragmatic Aphasia". Underlying assumptions regarding the use of the term aphasia to describe these deficits and the concept that pragmatics is inherent to language are questioned. The potential value of "pragmatics" as it relates to communicative intents, and its potential application to a definition of RHD communication impairments are also explored.  相似文献   
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Here we review the motivation for creating the enhancing neuroimaging genetics through meta-analysis (ENIGMA) Consortium and the genetic analyses undertaken by the consortium so far. We discuss the methodological challenges, findings, and future directions of the genetics working group. A major goal of the working group is tackling the reproducibility crisis affecting “candidate gene” and genome-wide association analyses in neuroimaging. To address this, we developed harmonized analytic methods, and support their use in coordinated analyses across sites worldwide, which also makes it possible to understand heterogeneity in results across sites. These efforts have resulted in the identification of hundreds of common genomic loci robustly associated with brain structure. We have found both pleiotropic and specific genetic effects associated with brain structures, as well as genetic correlations with psychiatric and neurological diseases.  相似文献   
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Obesity and left ventricular hypertrophy (LVH) have been identified as independent risk factors for cardiovascular events. The definition of LVH depends on the geometric algorithm used to calculate LV mass (LVM) by echocardiography and the method used to normalize LVM for body size. This study evaluates the effect of these methods on the prevalence of LVH in obese children. LVM for 109 obese and 109 age-matched non-obese children was calculated using M-mode or two-dimensional echocardiography (2DE). LVM was then normalized to height 2.7 as indexed LVM (LVMI), to body surface area (BSA), height, and lean body mass (LBM) as LVM Z-scores. LVH was defined as LVMI >95th ‰ using age-specific normal reference values or LVM Z-scores ≥2. The prevalence of LVH by LVMI and LVM Z-scores was compared. There was a correlation between LVM determined by M-mode and by 2DE (R 2 = 0.91), although M-mode LVM was greater than 2DE LVM. However, the difference between these values was greater in obese children than in non-obese children. Based on the method of normalization, the prevalence of LVH among obese children was 64 % using LVMI, 15 % using LVM Z-scores for height, 8 % using LVM Z-scores for BSA and 1 % using LVM Z-scores for LBM. Height-based normalization correlates with obesity and hypertension. The methods used to measure and normalize LVM have a profound influence on the diagnosis of LVH in obese children. Further study is needed to determine which method identifies children at risk for cardiovascular morbidity and mortality.  相似文献   
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BACKGROUND: The primary treatment for attention-deficit/hyperactivity disorder (ADHD) has been psychostimulants. Recently developed nonpsychostimulant treatments have allowed certain patients to switch from a psychostimulant to a nonpsychostimulant. However, the outcomes of such switches have not been systematically studied. OBJECTIVE: The purpose of this pilot study was to assess treatment tolerance and efficacy during a cross-taper transition from methylphenidate or amphetamine to atomoxetine among children and adolescents with ADHD. METHODS: This pilot study was conducted in patients (aged 6-17 years) with incomplete responses (failure to obtain full reduction/elimination of symptoms) or intolerance of adverse events (AEs) during psychostimulant treatment. Patients continued ongoing psychostimulant treatment during the first week of the study. Transition to atomoxetine began by administering atomoxetine 0.5 mg/kg . d plus full-dose psychostimulant for 1 week, followed in the second week by 1.2 mg/kg . d atomoxetine plus half-dose psychostimulant. Patients remained on 1.2 mg/kg . d atomoxetine monotherapy for the remaining 5 weeks. This stepwise transition was enacted due to the difference in pharmacodynamics between the psychostimulants and atomoxetine. Applying a stepwise cross-titration allowed for better control of ADHD symptoms during the intervening period. Change in ADHD symptoms, as measured by the mean change in the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-administered and -scored (ADHDRS-IV-Parent:Inv), was assessed from baseline to end point. RESULTS: Of the 62 subjects enrolled in the study, 39 (62.9%) were diagnosed as ADHD-combined type. Similar proportions were receiving methylphenidate (51.6%) and amphetamine (48.4%). Slightly more wished to switch due to inadequate response (53.2%) than intolerability (46.8%). Nine subjects discontinued at various times during the course of the study (patient or parent/caregiver decision [4], AE [2], protocol violation [2], and lack of efficacy [1]). Mean (SD) ADHDRS-IV-Parent:Inv total scores (n = 59, last-observation-carried-forward) improved significantly from baseline (visit 2) to an end point (32.1 [10.5] vs 22.6 [14.0]; P < 0.001). Of the 58 subjects answering in the atomoxetine monotherapy phase, 38 (65.5%) reported a preference for atomoxetine treatment over their previous psychostimulant. Tolerability results were as follows: 26 (44.1%) of 59 patients reported >or=1 AE, the most common being somnolence (4 [6.8%]), fatigue (3 [5.1%]), decreased appetite (3 [5.1%]), cough (3 [5.1%]), headache (3 [5.1%]), and contact dermatitis (2 [3.4%]). No clinically severe AEs were reported. Both mean (SD) diastolic (2.4 [7.8] mm Hg; P = 0.031) and systolic (2.4 [7.9] mm Hg; P = 0.029) blood pressures increased significantly from baseline to end point. Electrocardiography revealed a significant increase in mean (SD) heart rate (9.2 [11.6] bpm; P < 0.001) and a corresponding decrease in mean (SD) RR interval (-77.8 [98.2] ms; P < 0.001). Statistically significant, but mild, increases in diastolic pressure and heart rate were observed. CONCLUSION: These children and adolescent patients were successfully switched from methylphenidate or amphetamine to atomoxetine treatment, with resulting improvement in ADHD symptom severity from baseline in this pilot study.  相似文献   
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