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21.
Sedentary lifestyle patterns in children and adolescents, i.e. playing digital games, using computers and especially watching television, have been associated with obesity. However, not all sedentary behaviour has shown the same relevance to, and relationship with, obesity. Therefore, we conducted a review including published studies found in PubMed and other medical journals, dated between January 1990 and April 2007. The ages of the children and adolescents who were the object of the study ranged between 2 and 18 years. For the purpose of this paper, we selected cross-sectional, longitudinal and intervention studies. Sufficient evidence exists to recommend setting a limit to the time spent watching TV, especially for younger children. However, video games and computers do not represent such a high risk compared to watching TV, when they do not replace physical activity too much. In fact, there is no evidence to suggest that sedentary behaviour displaces physical activity levels. Mechanisms that explain the link between sedentariness and obesity are also discussed. Finally, future studies should take into account important mediators such as socioeconomic status and family structure.  相似文献   
22.
Epidemiology of hepatocellular carcinoma   总被引:5,自引:0,他引:5  
Year 2000 estimates of the incidence of cancer indicate that primary liver cancer remains the fifth most common malignancy in men and the eighth in women. The number of new cases has been predicted as 564,000, corresponding to 398,000 in men and 166,000 in women. The geographic areas at highest risk are located in Eastern Asia, Middle Africa, and some countries of Western Africa. Changes in incidence among migrant populations underline the predominant role of environmental factors in the etiology of primary liver cancer. In high-risk countries, the early cases of primary liver cancer occur already at ages 20 and above, underlying the impact of viral exposures early in life. In countries at low risk, primary liver cancer is rare before the 50s, translating the impact of late exposures with moderate risks and long latency intervals. Sex ratios are typically between 2 and 4. The incidence of primary liver cancer is increasing in several developed countries including the United States, and the increase will likely continue for several decades. The trend has a dominant cohort effect related to exposures to hepatitis B and C viruses. The variability of primary liver cancer incidence is largely explained by the distribution and the natural history of the hepatitis B and C viruses. The attributable risk estimates for the combined effects of these infections account for well over 80% of liver cancer cases worldwide. Primary liver cancer is the first human cancer largely amenable to prevention using hepatitis B virus vaccines and screening of blood and blood products for hepatitis B and C viruses.  相似文献   
23.
24.
Next‐generation sequencing (NGS) has revolutionized genomic research and is set to have a major impact on genetic diagnostics thanks to the advent of benchtop sequencers and flexible kits for targeted libraries. Among the main hurdles in NGS are the difficulty of performing bioinformatic analysis of the huge volume of data generated and the high number of false positive calls that could be obtained, depending on the NGS technology and the analysis pipeline. Here, we present the development of a free and user‐friendly Web data analysis tool that detects and filters sequence variants, provides coverage information, and allows the user to customize some basic parameters. The tool has been developed to provide accurate genetic analysis of targeted sequencing of common high‐risk hereditary cancer genes using amplicon libraries run in a GS Junior System. The Web resource is linked to our own mutation database, to assist in the clinical classification of identified variants. We believe that this tool will greatly facilitate the use of the NGS approach in routine laboratories.  相似文献   
25.

Background

The Children's Somatization Inventory (CSI) has proved to be a suitable measure to assess somatic symptoms in pediatric patients, but additional research was needed to evaluate its psychometric properties in community populations.

Purpose

The objective of the present study was to examine psychometric properties and factorial structure of the instrument among a nonclinical sample of Spanish children.

Method

The 24-item version of the CSI and two self-report measures of anxiety and depression were administered to 1,111 Spanish children aged 8 to 12.

Results

Exploratory analysis suggested a factorial structure composed of three factors: pseudoneurologic symptoms, gastrointestinal symptoms, and pain. Due to confirmatory analysis indicating a poor fit for the three-factor model, two alternative models were tested. A six-item single factor identified in a previous study with an American community sample showed the best fit (RMSEA?=?0.04; GFI?=?0.99; AGFI?=?0.98; CFI?=?0.98; χ2/gl?=?2.71). The internal consistency for the six-item version was acceptable (ω?=?.71), and the construct validity with anxiety (r?=?.53) and depression (r?=?.38) measures was adequate.

Conclusion

The six-item version of the CSI demonstrated to be a reliable measure for assessing somatization symptoms in Spanish children.  相似文献   
26.
27.
Endobronchial metastases (EBM) secondary to extrapulmonary primary tumours are rare. The most common solid malignant tumours associated with EBM are breast, renal and colorectal carcinomas. This case report describes the first documented case of EBM from anal canal carcinoma. This neoplasm constitutes less than 1% of colorectal tumours. The clinical presentation of this entity is variable, being asymptomatic in more than 50% of cases. Generally, EBM are diagnosed in advanced stages and the survival after the diagnosis is poor. It is therefore an exceptional clinical manifestation in which bronchoscopy has an important role in the diagnosis and the treatment.  相似文献   
28.

Introduction

Arrhythmogenic right ventricular cardiomyopathy is an inherited disease characterized by a progressive myocardium fibrofatty replacement. This abnormality disrupts electrical transmission causing ventricular arrhythmias and sudden cardiac death. This genetic disease is transmitted mainly with an autosomal dominant pattern. Our aim was to identify the genetic defect responsible for the pathology in a Spanish family, and to perform its phenotype connotations.

Material and methods

A total of 15 individuals in a three-generation Spanish family were screened after the sudden cardiac death of one family member. All they underwent a complete physical examination, 12-lead electrocardiogram, 2-dimensional echocardiography, magnetic resonance imaging, exercise stress test, 24-h Holter and genetic testing.

Results

Autopsy revealed the presence of biventricular arrhythmogenic dysplasia in deceased member. Six family members showed clinical symptoms but only three of them fulfilled definite diagnostic criteria of the disease. Genetic analysis showed a novel nonsense genetic variation in nine family members. All family members with clinical symptoms carried the genetic variation.

Conclusions

Genetic testing in families affected by arrhythmogenic right ventricular cardiomyopathy helps to identify the genetic cause responsible for the disease. The incomplete penetrance and variable phenotypic expression highlights the need of comprehensive genetic analysis and further phenotype implications of genetics to clarify the pathophysiology of the disease.  相似文献   
29.
AIM: To compare rifaximin and insulin-like growth factor (IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal occlusion.METHODS: Rats with CCl4-induced cirrhosis with ascites plus portal vein occlusion and controls were randomized into six groups: Cirrhosis; Cirrhosis + IGF-1; Cirrhosis + rifaximin; Controls; Controls + IGF-1; and Controls + rifaximin. An oral glutamine-challenge test was performed, and plasma and cerebral ammonia, glucose, bilirubin, transaminases, endotoxemia, brain water content and ileocecal cultures were measured and liver histology was assessed.RESULTS: Rifaximin treatment significantly reduced bacterial overgrowth and endotoxemia compared with cirrhosis groups, and improved some liver function parameters (bilirubin, alanine aminotransferase and aspartate aminotransferase). These effects were associated with a significant reduction in cerebral water content. Blood and cerebral ammonia levels, and area-under-the-curve values for oral glutamine-challenge tests were similar in rifaximin-treated cirrhotic rats and control group animals. By contrast, IGF-1 administration failed to improve most alterations observed in cirrhosis.CONCLUSION: By reducing gut bacterial overgrowth, only rifaximin was capable of normalizing plasma and brain ammonia and thereby abolishing low-grade brain edema, alterations associated with hepatic encephalopathy.  相似文献   
30.
Progressive multifocal leukoencephalopathy is the most common clinical presentation of JC virus (JCV)‐associated central nervous system (CNS) disease and has emerged as a major safety concern in multiple sclerosis patients treated with the monoclonal antibody natalizumab. Here we report clinical, radiological, and histological findings of a case of cerebellar granule cell neuronopathy (GCN), a JCV‐associated CNS disease, so far unreported amongst patients treated with natalizumab. GCN should be considered as a JCV CNS manifestation in patients with newly developed, progressive cerebellar signs under natalizumab treatment, especially in cases where cerebellar atrophy can be visualized by magnetic resonance imaging. Ann Neurol 2013;74:622–626  相似文献   
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