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81.
Hélène Cochet Laurie Centelles Marianne Jover Suzy Plachta Jacques Vauclair 《Laterality》2013,18(4):501-516
Manual asymmetries emerge very early in development and several researchers have reported a significant right-hand bias in toddlers although this bias fluctuates depending on the nature of the activity being performed. However, little is known about the further development of asymmetries in preschoolers. In this study, patterns of hand preference were assessed in 50 children aged 3–5 years for different activities, including reaching movements, pointing gestures and symbolic gestures. Contrary to what has been reported in children before 3 years of age, we did not observe any difference in the mean handedness indices obtained in each task. Moreover, the asymmetry of reaching was found to correlate with that of pointing gestures, but not with that of symbolic gestures. In relation to the results reported in infants and adults, this study may help deciphering the mechanisms controlling the development of handedness by providing measures of manual asymmetries in an age range that has been so far rather neglected. 相似文献
82.
Jacob D. Bolzenius David H. Laidlaw Ryan P. Cabeen Thomas E. Conturo Amanda R. McMichael Elizabeth M. Lane Jodi M. Heaps Lauren E. Salminen Laurie M. Baker John Gunstad Robert H. Paul 《Brain imaging and behavior》2013,7(3):300-306
Increased body mass index (BMI) has been linked to various detrimental health outcomes, including cognitive dysfunction. Recent work investigating associations between obesity and the brain has revealed decreased white matter microstructural integrity in individuals with elevated BMI, independent of age or comorbid health conditions. However, the relationship between high BMI and white matter fiber bundle length (FBL), which represents a novel metric of microstructural brain integrity, remains unknown. The present study utilized quantitative tractography based on diffusion tensor imaging (DTI) to investigate the relationship between BMI and FBL in 72 otherwise healthy older adults (24 males, 48 females). All participants were between 51 and 85 years of age (M?=?63.26, SD?=?8.76). Results revealed that elevated BMI was associated with shorter FBL in the temporal lobe, independent of age (p?<?.01). In addition, increased age was associated with shorter frontal, temporal, and whole brain FBL (all p values?<?.01). These findings indicate that, while increased age is an important factor associated with reduced FBL, high BMI is uniquely associated with reduced FBL in the temporal lobe. These data offer evidence for additive adverse effects of high BMI on the brain, especially in areas already vulnerable to aging processes and age-related neurodegenerative diseases. Further research is necessary to determine the physiological mechanisms associated with the shortening of FBL in individuals with high BMI. 相似文献
83.
Laurie M. Baker Leanne M. Williams Mayuresh S. Korgaonkar Ronald A. Cohen Jodi M. Heaps Robert H. Paul 《Brain imaging and behavior》2013,7(2):196-203
Previous studies of early life trauma suggest that in addition to its emotional impact, exposure to early life stress (ELS) is associated with alterations in brain structure. However, little attention has been devoted to the relationship between emotional processing and brain integrity as a function of age of ELS onset. In the present study we examined whether ELS onset in older ages of youth rather than younger ages is associated with smaller limbic and basal ganglia volumes as measured by magnetic resonance imaging (MRI). We hypothesized that later age of manifestation during youth is associated with smaller volumetric morphology in limbic and basal ganglia volumes in adulthood. A total of 173 individuals were divided into three groups based on the age of self-reported ELS. The three groups included individuals only experiencing early childhood ELS (1 month–7 years, n = 38), those only experiencing later childhood ELS (8 years –17 years, n = 59), and those who have not experienced ELS (n = 76). Anterior cingulate cortex (ACC), hippocampus, amygdala, insula and caudate volumes were measured using a T1-weighted MRI. Analyses confirmed that later childhood ELS was associated with volumetric reductions in the ACC and insula volumes, while ELS experienced between the ages of 1 month and 7 years was not associated with lower brain volumes in these regions. The results may reflect the influence of more fully developed emotional processing of ELS on the developing brain and reinforce a body of research implicating both the ACC and insula in neuropsychiatric disorders and emotional regulation. 相似文献
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Lambert L Blais C Hamel D Brown K Rinfret S Cartier R Giguère M Carroll C Beauchamp C Bogaty P 《The Canadian journal of cardiology》2012,28(2):162-168
Background
The evaluation of care and the surveillance of disease are important in respect to cardiovascular disease because it is prevalent and costly. In Canada, medico-administrative hospital data are readily available, continuously updated, and offer comprehensive coverage of the patient population. However, there is concern about the quality of the information.Methods
The reliability and predictive capability of comorbidity data contained within Québec's hospital discharge database were assessed in comparison with data collected by clinical medical record reabstraction in a sample of 1989 patients hospitalized from 2002 to 2006 in a mix of 13 hospitals. Patients either had a principal diagnosis of myocardial infarction or underwent angioplasty or bypass surgery. Twenty-one comorbidities included in the Charlson comorbidity index or known to be associated with mortality were validated via medical record reabstraction.Results
Of 14 comorbidities with > 2% prevalence, 8 had excellent agreement with medical record review (κ > 0.8) while 6 had substantial agreement (κ > 0.6). In general, positive predictive values were high, while measures of sensitivity were more variable. Univariate associations between comorbidities and 30-day and 1-year mortality were generally similar in the 2 data sources. Comorbidities retained in the final multivariate stepwise regression models from each data source were almost identical, as were the 2 models' abilities to predict mortality.Conclusions
Hospital discharge data in Québec are, in general, reliably coded and compare favourably with clinical medical record review in their ability to predict mortality. It appears sufficiently reliable to provide useful information about clinical outcomes of cardiac care and to identify problems that warrant investigation. 相似文献87.
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89.
Background
Proven short-term effectiveness of obesity therapy should be re-evaluated in the long-term. The objective of this paper is to determine the long-term (10 years) outcome for patients from a randomised controlled trial (RCT).Methods
A RCT in 2002 compared laparoscopic adjustable gastric band (LAGB) for obesity with non-surgical therapy. Follow-up has been conducted at 10 years. Eighty patients (BMI 30–35) were randomised to a non-surgical or a surgical program. Outcome data are available on 37 (92.5 %) of the surgical patients and 27 (62.5 %) of the non-surgical patients at 10 years.Results
Weight change, the metabolic syndrome, quality of life, adverse events and direct costs of the surgical cohort were the main results of the study. A durable weight loss is present in the surgical group with a mean (SD) 10-year weight loss of 14.1 (7.7)?kg (63.4 % EWL), better than the non-surgical group (mean (SD)?=?0.4 (10.5)?kg; p?<?0.001). The metabolic syndrome was reduced from 14 to 4 of the 37 patients who completed 10 years within the LAGB groups. Proximal gastric enlargements occurred in 17 (30 %) of the 57 who had LAGB and removal of the band occurred in 7 (12 %). The annual maintenance costs including additional surgery was AUD $765 per patient per year.Conclusions
Bariatric surgery with the LAGB can achieve long-term weight reduction which is better than a program of non-surgical therapy. There is also a sustained reduction of the metabolic syndrome. There is a significant maintenance requirement after LAGB. 相似文献90.