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991.
Background: Children with severe intestinal failure and prolonged dependence on parenteral nutrition are susceptible to the development of parenteral nutrition–associated liver disease (PNALD). The purpose of this clinical guideline is to develop recommendations for the care of children with PN‐dependent intestinal failure that have the potential to prevent PNALD or improve its treatment. Method: A systematic review of the best available evidence to answer a series of questions regarding clinical management of children with intestinal failure receiving parenteral or enteral nutrition was undertaken and evaluated using concepts adopted from the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) Working Group. A consensus process was used to develop the clinical guideline recommendations prior to external and internal review and approval by the American Society for Parenteral and Enteral Nutrition Board of Directors. Questions: (1) Is ethanol lock effective in preventing bloodstream infection and catheter removal in children at risk of PNALD? (2) What fat emulsion strategies can be used in pediatric patients with intestinal failure to reduce the risk of or treat PNALD? (3) Can enteral ursodeoxycholic acid improve the treatment of PNALD in pediatric patients with intestinal failure? (4) Are PNALD outcomes improved when patients are managed by a multidisciplinary intestinal rehabilitation team?  相似文献   
992.

Objective

Given that lifestyleshave similar determinants and that school-based interventions are usually targeted at all the risks that affect adolescents, the objective of this systematic review was to summarize the characteristics and effects of school-based interventions acting on different behavioral domains of adolescent health promotion.

Methods

The review process was conducted by two independent reviewers who searched PubMed, Scopus, PsycINFO, and ERIC databases for experimental or observational studies with at least two measures of results published from 2007 to 2011, given that the research information available doubles every 5 years. Methodological quality was assessed with a standardized tool.

Results

Information was extracted from 35 studies aiming to prevent risk behaviors and promote healthy nutrition, physical activity, and mental and holistic health. Activities were based on theoretical models and were classified into interactive lessons, peer mediation, environmental changes, parents’ and community activities, and tailored messages by computer-assisted training or other resources, usually including multiple components. In some cases, we identified some moderate to large, short- and long-term effects on behavioral and intermediate variable.

Conclusions

This exhaustive review found that well-implemented interventions can promote adolescent health. These findings are consistent with recent reviews. Implications for practice, public health, and research are discussed.  相似文献   
993.
Samples of two carnivore fish species (Hoplias malabaricus and Serrasalmus brandtii) were collected along Contas River, northeastern Brazil, to determine the levels of Co, Cr, Cu, Fe, Mn, Ni and Pb in edible and non-edible tissues of these important local fisheries resources. Lead could not be quantified in most of the samples, while the other metals were detected in both species. In edible parts, Cr levels were above Brazilian threshold limits in all specimens and Ni was at high concentration in S. brandtii individuals from one collection site. In non-edible parts (viscera), besides Cr, Cu concentration was higher than that recommended by Brazilian laws. Both fish species proved to be sensitive to environmental contamination. Despite the different ecological characteristics, such as vagility and feeding strategy, these fish showed that aquatic predators are efficient bioindicators of water quality and biomagnification.  相似文献   
994.
Background: The association between human blood DNA global methylation and global hydroxymethylation has not been evaluated in population-based studies. No studies have evaluated environmental determinants of global DNA hydroxymethylation, including exposure to metals.Objective: We evaluated the association between global DNA methylation and global DNA hydroxymethylation in 48 Strong Heart Study participants for which selected metals had been measured in urine at baseline and DNA was available from 1989–1991 (visit 1) and 1998–1999 (visit 3).Methods: We measured the percentage of 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in samples using capture and detection antibodies followed by colorimetric quantification. We explored the association of participant characteristics (i.e., age, adiposity, smoking, and metal exposure) with both global DNA methylation and global DNA hydroxymethylation.Results: The Spearman’s correlation coefficient for 5-mC and 5-hmC levels was 0.32 (p = 0.03) at visit 1 and 0.54 (p < 0.001) at visit 3. Trends for both epigenetic modifications were consistent across potential determinants. In cross-sectional analyses, the odds ratios of methylated and hydroxymethylated DNA were 1.56 (95% CI: 0.95, 2.57) and 1.76 (95% CI: 1.07, 2.88), respectively, for the comparison of participants above and below the median percentage of dimethylarsinate. The corresponding odds ratios were 1.64 (95% CI: 1.02, 2.65) and 1.16 (95% CI: 0.70, 1.94), respectively, for the comparison of participants above and below the median cadmium level. Arsenic exposure and metabolism were consistently associated with both epigenetic markers in cross-sectional and prospective analyses. The positive correlation of 5-mC and 5-hmC levels was confirmed in an independent study population.Conclusions: Our findings support that both epigenetic measures are related at the population level. The consistent trends in the associations between these two epigenetic modifications and the characteristics evaluated, especially arsenic exposure and metabolism, suggest the need for understanding which of the two measures is a better biomarker for environmental epigenetic effects in future large-scale epidemiologic studies.Citation: Tellez-Plaza M, Tang WY, Shang Y, Umans JG, Francesconi KA, Goessler W, Ledesma M, Leon M, Laclaustra M, Pollak J, Guallar E, Cole SA, Fallin MD, Navas-Acien A. 2014. Association of global DNA methylation and global DNA hydroxymethylation with metals and other exposures in human blood DNA samples. Environ Health Perspect 122:946–954; http://dx.doi.org/10.1289/ehp.1306674  相似文献   
995.
996.
997.
Vaccination against COVID-19 has been promoted as a way to protect oneself and others from infection. To ensure the comprehensive acceptance of COVID-19 vaccines, the factors that affect COVID-19 vaccination hesitancy should be examined. This study aimed to identify the factors that affect COVID-19 vaccination hesitancy among Korean adults, focusing on COVID-19 knowledge and attitudes toward vaccination. This was a cross-sectional study conducted with 2286 Korean adults aged 20–64 years. Demographic characteristics, knowledge regarding COVID-19, and attitudes toward vaccination were assessed. A generalized linear model with Poisson regression was used to identify factors associated with COVID-19 vaccination hesitancy. Approximately 67% of the COVID-19 knowledge-related questions were correctly answered. A neutral attitude toward vaccination and relatively low vaccination hesitancy were found. COVID-19 vaccination hesitancy was affected by individuals' attitudes toward vaccination, as well as their gender and age, but not by their knowledge. Interventions or policies considering gender and age could be helpful in reducing COVID-19 vaccination hesitancy. Strategies to disseminate more accurate and novel information related to the COVID-19 vaccines should be implemented.  相似文献   
998.
999.
Spectral entropy (SE), also known as Shannon entropy, is a useful parameter for quantifying the global regularity of the electroencephalographic (EEG) signal. Hence, it is of interest in the assessment of the electrophysiological correlates of cognitive processing in schizophrenia. However, to date, SE has been barely used in studies comparing resting EEG recordings between patients and controls. In this work, we compared SE between resting baseline [?250 0] ms and active task [150 550] ms windows of a P300 task in 31 patients with schizophrenia and 38 controls. Moreover, we also calculated the median frequency (MF) and relative power in each frequency band for these windows to assess the correlates of the possible SE differences. Controls showed a significant (p < 0.0029) SE decrease (i.e., meaning higher signal regularity) from baseline to the active task window at parietal and central electrode sites. This SE decrease from baseline to active conditions was significantly lower in patients. In controls, this SE decrease was accompanied by a statistically significant decrease in MF (i.e., a significant slowing of the EEG activity), not observed in patients. In this latter group, the difference in SE between resting baseline and active task windows was inversely correlated to positive and total symptoms scores, as measured with the positive and negative symptoms scale. Our data support the relevance of SE in the study of cerebral processing in schizophrenia.  相似文献   
1000.
Binocularity is a key property of primary visual cortex (V1) neurons that is widely used to study synaptic integration in the brain and plastic mechanisms following an altered visual experience. However, it is not clear how the inputs from the two eyes converge onto binocular neurons, and how their interaction is modified by an unbalanced visual drive. Here, using visual evoked potentials recorded in the juvenile rat V1, we report evidence for a suppressive mechanism by which contralateral eye activity inhibits responses from the ipsilateral eye. Accordingly, we found a lack of additivity of the responses evoked independently by the two eyes in the V1, and acute silencing of the contralateral eye resulted in the enhancement of ipsilateral eye responses in cortical neurons. We reverted the relative cortical strength of the two eyes by suturing the contralateral eye shut [monocular deprivation (MD)]. After 7 days of MD, there was a loss of interocular suppression mediated by the contralateral, deprived eye, and weak inputs from the closed eye were functionally inhibited by interhemispheric callosal pathways. We conclude that interocular suppressive mechanisms play a crucial role in shaping normal binocularity in visual cortical neurons, and a switch from interocular to interhemispheric suppression represents a key step in the ocular dominance changes induced by MD. These data have important implications for a deeper understanding of the key mechanisms that underlie activity‐dependent rearrangements of cortical circuits following alteration of sensory experience.  相似文献   
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