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BackgroundThe emergence and media coverage of COVID-19 may have affected influenza search patterns, possibly affecting influenza surveillance results using Google Trends.ObjectiveWe aimed to investigate if the emergence of COVID-19 was associated with modifications in influenza search patterns in the United States.MethodsWe retrieved US Google Trends data (relative number of searches for specified terms) for the topics influenza, Coronavirus disease 2019, and symptoms shared between influenza and COVID-19. We calculated the correlations between influenza and COVID-19 search data for a 1-year period after the first COVID-19 diagnosis in the United States (January 21, 2020 to January 20, 2021). We constructed a seasonal autoregressive integrated moving average model and compared predicted search volumes, using the 4 previous years, with Google Trends relative search volume data. We built a similar model for shared symptoms data. We also assessed correlations for the past 5 years between Google Trends influenza data, US Centers for Diseases Control and Prevention influenza-like illness data, and influenza media coverage data.ResultsWe observed a nonsignificant weak correlation (ρ= –0.171; P=0.23) between COVID-19 and influenza Google Trends data. Influenza search volumes for 2020-2021 distinctly deviated from values predicted by seasonal autoregressive integrated moving average models—for 6 weeks within the first 13 weeks after the first COVID-19 infection was confirmed in the United States, the observed volume of searches was higher than the upper bound of 95% confidence intervals for predicted values. Similar results were observed for shared symptoms with influenza and COVID-19 data. The correlation between Google Trends influenza data and CDC influenza-like-illness data decreased after the emergence of COVID-19 (2020-2021: ρ=0.643; 2019-2020: ρ=0.902), while the correlation between Google Trends influenza data and influenza media coverage volume remained stable (2020-2021: ρ=0.746; 2019-2020: ρ=0.707).ConclusionsRelevant differences were observed between predicted and observed influenza Google Trends data the year after the onset of the COVID-19 pandemic in the United States. Such differences are possibly due to media coverage, suggesting limitations to the use of Google Trends as a flu surveillance tool.  相似文献   
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An in situ evaluation of the potential rehardening effect of fluoridated and non-fluoridated toothpastes with or without air polishing was conducted. Ten volunteers, using acrylic palatal appliances containing two bovine enamel blocks with artificial carious lesions, took part in this study. Four times a day, after the main meals and at night, the volunteers, in a habitual way, brushed their natural teeth with the dentifrice indicated to the experimental design and after that the appliances were put again into the mouth. They were divided into 4 different groups: G1 - control - non-fluoridated dentifrice; G2 - fluoridated dentifrice; G3 - non-fluoridated dentifrice, but having a previous prophylaxis using air polishing; G4 - fluoridated dentifrice and previous air polishing. The effects of treatments on enamel rehardening were evaluated in the blocks that were assessed by surface microhardness, and the percentage of surface microhardness change (%reh) was calculated in relation to the baseline values. The results showed that %reh was higher in the groups with fluoridated dentifrice, and professional prophylaxis did not have an additional effect in the groups of fluoridated dentifrices (p<0.05). The data suggested that, in the absence of fluoride, removal of dental plaque helped to increase the process of enamel rehardening.  相似文献   
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Non-occlusion of the internal mammary artery side branches may cause ischemia due to flow diversion after coronary artery bypass grafting.The authors present the case of a 67-year-old man with recurrent angina after undergoing myocardial revascularization with a left internal mammary artery to left anterior descending bypass. He presented with impaired anterior wall myocardial perfusion in the setting of a patent left internal mammary artery side branch. Effective percutaneous treatment was carried out through coil embolization, with improved flow and clinical symptoms, confirmed through ischemia testing.Coronary steal through a patent mammary artery side branch is a controversial phenomenon and this type of intervention should be considered only in carefully selected patients.  相似文献   
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