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61.
This article provides a general framework for understanding the use of information and communication technology in education and discusses the impact of computer usage on students' health and development. Potential beneficial and harmful effects of computer use by children are discussed. Early epidemiological and laboratory studies have indicated that children are at least of similar risk of developing musculoskeletal and vision problems as adults, and musculoskeletal and visual health problems developed in childhood are likely to persist into adulthood. This article, therefore, aims to provide a reflection on the deficits of existing policy and recommendations for child‐specific guidelines in computer use.  相似文献   
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63.

OBJECTIVE:

Prevention is the best treatment for cerebrovascular disease, which is why early diagnosis and the immediate treatment of carotid stenosis contribute significantly to reducing the incidence of stroke. Given its silent nature, 80% of stroke cases occur in asymptomatic individuals, emphasizing the importance of screening individuals with carotid stenosis and identifying high-risk groups for the disease. The aim of this study was to determine the prevalence and the most frequent risk factors for carotid stenosis.

METHODS:

A transversal study was conducted in the form of a stroke prevention campaign held on three non-consecutive Saturdays. During the sessions, carotid stenosis diagnostic procedures were performed for 500 individuals aged 60 years or older who had systemic arterial hypertension and/or diabetes mellitus and/or coronary heart disease and/or a family history of stroke.

RESULTS:

The prevalence of carotid stenosis in the population studied was 7.4%, and the most frequent risk factors identified were mean age of 70 years, carotid bruit, peripheral obstructive arterial disease, coronary insufficiency and smoking. Independent predictive factors of carotid stenosis include the presence of carotid bruit or peripheral obstructive arterial disease and/or coronary insufficiency.

CONCLUSIONS:

The population with peripheral obstructive arterial disease and/or coronary insufficiency and carotid bruit should undergo routine screening for carotid stenosis.  相似文献   
64.

Background

Chronic obstructive pulmonary disease (COPD) and asthma are underdiagnosed in primary care.

Aim

To determine how often COPD or asthma are present in middle-aged and older patients who consult their GP for persistent cough.

Design of study

A cross-sectional study in 353 patients older than 50 years, visiting their GP for persistent cough and not known to have COPD or asthma.

Setting

General practice in the Netherlands.

Method

All participants underwent extensive diagnostic work-up, including symptoms, signs, spirometry, and body plethysmography. All results were studied by an expert panel to diagnose or exclude COPD and/or asthma. The reproducibility of the panel diagnosis was assessed by calculation of Cohen''s κ statistic in a sample of 41 participants.

Results

Of the 353 participants, 102 (29%, 95% confidence interval [CI] = 24 to 34%) were diagnosed with COPD. In 14 of these 102 participants, both COPD and asthma were diagnosed (4%, 95% CI = 2 to 7%). Asthma (without COPD) was diagnosed in 23 (7%, 95% CI = 4 to 10%) participants. Mean duration of cough was 93 days (median 40 days). The reproducibility of the expert panel was good (Cohen''s κ = 0.90).

Conclusion

In patients aged over 50 years who consult their GP for persistent cough, undetected COPD or asthma is frequently present.  相似文献   
65.

Objectives

To evaluate the effectiveness of natural compounds containing mouthrinse (NCCM) as an adjunct to unsupervised oral hygiene in the management of dental plaque and gingivitis.

Materials and methods

An electronic search for clinical studies of NCCMs was conducted in Medline-PubMed, the Cochrane Central Register of Controlled Trials and EMBASE for a period spanning from the earliest available date in each database up to February 2013. Plaque index, gingival index, and gingival bleeding index were selected as primary outcomes. The methodological quality of the studies was assessed according to the “Levels of Evidence” outlined by the Center of Evidence-Based Medicine, and to the Jadad scale.

Results

The screen yielded 2,236 titles and abstracts that met the inclusion criteria. These identified 11 clinical trials testing 13 different NCCMs, and were used for data extraction. Heterogeneity and the limited number of studies on any individual NCCM precluded a formal meta-analysis. Of the 13 NCCMs tested, eight demonstrated positive results, and few reported any adverse effects or events.

Conclusions

Evidence proving the effectiveness of NCCM as an adjunct to unsupervised oral hygiene for plaque and gingivitis control is still insufficient. However, some natural products (compounds) may have oral health benefits, so further high-quality study is warranted.

Clinical relevance

This review provides an overview of the strength of clinical evidence regarding the effectiveness of natural compounds containing mouthrinses in promoting gingival health.  相似文献   
66.
8-Oxo-2'-deoxyguanosine (8-oxo-dG) is emerging as a useful marker for oxidative DNA damage. Reported basal levels determined by 32P- postlabeling (PPL) method were 10-fold or more higher than those obtained with HPLC/electrochemical detection (ECD). This discrepancy was investigated. In commercial calf thymus DNA, levels of 4 +/- 1 and 64 +/- 14 8-oxo-dG per 10(6) 2'-deoxynucleosides (dN) were measured by the standard HPLC/ECD and PPL methods, respectively. DNA digestion by micrococcal nuclease/spleen phosphodiesterase and nuclease P1 (as used in the standard PPL method), followed by ECD analysis resulted in a level of 8 +/- 3. In calf thymus DNA spiked with chemically synthesized 8-oxo-dGp to give an increment of 9 8-oxo-dG/10(6) dN, the added standard produced a significant increase with HPLC/ECD but not PPL. After spiking the DNA with 90 8-oxo-dG/10(6) dN, the added 8-oxo-dGp was detectable also with PPL, with a labeling efficiency of 65%. In order to investigate the role of ionizing radiation from 32P for the higher 8-oxo-dG levels in PPL, incubation times and amounts of radioactivity in the phosphorylation reaction with commercial dGp were increased, and external irradiation of commercial dG with 32P was investigated. All modifications resulted in higher values of 8-oxo-dG measured, but the effect was not large enough to fully explain the discrepancy between PPL and HPLC/ECD. Using [gamma-33P]ATP instead of [gamma-32P]ATP or adding [33P]phosphate to a 32P-PPL assay resulted in even higher levels of 8-oxo-dG measured. The increase in 8-oxo-dG levels during the PPL workup is attributed to the presence and oxidation of unmodified dGp in the reaction mixture. For a determination of true basal levels, the PPL method will have to be modified, including the removal of dGp prior to the phosphorylation reaction.   相似文献   
67.
Background: Curcumin was shown to reduce epithelial-mesenchymal transition (EMT) markers in previous shortterm studies. This study was aimed to investigate the potential of curcumin in the prevention of EMT activation inMCF-7 cells induced by endoxifen. Methods: MCF-7 breast cancer cells were treated with Endoxifen 1000 nM+betaestradiol1 nM with or without curcumin (8.5μM or 17 μM). Cells treated with dimethyl sulfoxide (DMSO) 0.001%were used as negative control. After 8 weeks of continuous treatment, the cells were counted, analyzed for mRNAE-cadherin, vimentin, TGF-β expression, total reactive oxygen species (ROS) and observed for morphological changesusing confocal microscope and transmission electron microscope. Result: MCF-7 cell viability was increased inendoxifen + β-estradiol group. Cell viability was significantly decreased in curcumin 17 μM, but not in curcumin8.5 μM group. Analysis of EMT markers at week 8 indicates that there were increase in vimentin and TGF-β mRNAexpressions, while E-cadherin mRNA expressions and TGF-β1 protein concentrations were shown to decrease. Theresults showed that administration of curcumin in all the dose administered were incapable improving the expressionsof vimentin, TGF-β1 and E-cadherin. There was a decrease in ROS concentration in curcumin treated cells (8.5 μM)while in curcumin 17 μM, ROS concentration was increased. Morphological observation using confocal microscopeand TEM showed the presence of mesenchymal cells and adherens junction. Conclusion: endoxifen treatments foreight weeks resulted in upregulation of EMT markers and changes in morphology of MCF-7 breast cancer cells. Theaddition of curcumin did not prevent the activation of EMT.  相似文献   
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69.
Introduction: Patients with locally advanced nasopharyngeal carcinoma (NPC) commonly present with cranial nerve (CN) involvement, which can cause significant morbidity. We aimed to characterise the pattern of involvement and outcomes of these patients, as well as determine if these differed according to the mode of diagnosis. Methods: Patients were included if they had non‐distant metastatic NPC, presented with CN involvement and completed radiotherapy treatment between 2002 and 2008. The clinical response was categorised as complete response, partial response, stable or progressive disease. The radiological response was assessed using the Response Evaluation Criteria in Solid Tumors criteria. The loco‐regional control and disease‐free survival rates were estimated with the Kaplan–Meier method. Results: Forty‐seven patients fulfilled the inclusion criteria. CN lesions were diagnosed on clinical examination in 15% of patients, radiologically in 40% and both clinically and radiologically in 45% of patients. A complete or partial response of the CN lesions was seen clinically in 82% and radiologically in 95% of patients. The 3‐year local relapse free survival was 64.3%, distant metastasis‐free survival was 46.1% and overall survival was 82.8%. There were no differences in outcomes between patients with clinically versus radiologically detected CN lesions. Conclusion: Most of these patients are likely to undergo clinical and/or radiological resolution of the nerve lesions following chemoradiotherapy, but the outcome was not determined by the mode of diagnosis (radiological or clinical).  相似文献   
70.
    
Background: Nonalcoholic fatty liver disease (NAFLD) is associated with impaired renal function, and both diseases often occur alongside other metabolic disorders. However, the prevalence and risk factors for impaired renal function in patients with NAFLD remain unclear. The objective of this study was to identify the prevalence and risk factors for renal impairment in NAFLD patients.Methods: All adults aged 18-70 years with ultrasound-diagnosed NAFLD and transient elastography ex- amination from eight Asian centers were enrolled in this prospective study. Liver fibrosis and cirrhosis were assessed by FibroScan-aspartate aminotransferase (FAST), Agile 3+ and Agile 4 scores. Impaired renal function and chronic kidney disease (CKD) were defined by an estimated glomerular filtration rate (eGFR) with value of < 90 mL/min/1.73 m2 and < 60 mL/min/1.73 m2 , respectively, as estimated by the CKD-Epidemiology Collaboration (CKD-EPI) equation.Results: Among 529 included NAFLD patients, the prevalence rates of impaired renal function and CKD were 37.4% and 4.9%, respectively. In multivariate analysis, a moderate-high risk of advanced liver fibrosis and cirrhosis according to Agile 3+ and Agile 4 scores were independent risk factors for CKD ( P < 0.05). Furthermore, increased fasting plasma glucose (FPG) and blood pressure were significantly associated with impaired renal function after controlling for the other components of metabolic syndrome ( P < 0.05). Compared with patients with normoglycemia, those with prediabetes [FPG ≥5.6 mmol/L or hemoglobin A1c (HbA1c) ≥5.7%] were more likely to have impaired renal function ( P < 0.05).Conclusions: Agile 3+ and Agile 4 are reliable for identifying NAFLD patients with high risk of CKD. Early glycemic control in the prediabetic stage might have a potential renoprotective role in these patients.  相似文献   
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