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81.
Glaucoma is one of the leading causes of irreversible but preventable blindness in working age populations. Color fundus photography (CFP) is the most cost-effective imaging modality to screen for retinal disorders. However, its application to glaucoma has been limited to the computation of a few related biomarkers such as the vertical cup-to-disc ratio. Deep learning approaches, although widely applied for medical image analysis, have not been extensively used for glaucoma assessment due to the limited size of the available data sets. Furthermore, the lack of a standardize benchmark strategy makes difficult to compare existing methods in a uniform way. In order to overcome these issues we set up the Retinal Fundus Glaucoma Challenge, REFUGE (https://refuge.grand-challenge.org), held in conjunction with MICCAI 2018. The challenge consisted of two primary tasks, namely optic disc/cup segmentation and glaucoma classification. As part of REFUGE, we have publicly released a data set of 1200 fundus images with ground truth segmentations and clinical glaucoma labels, currently the largest existing one. We have also built an evaluation framework to ease and ensure fairness in the comparison of different models, encouraging the development of novel techniques in the field. 12 teams qualified and participated in the online challenge. This paper summarizes their methods and analyzes their corresponding results. In particular, we observed that two of the top-ranked teams outperformed two human experts in the glaucoma classification task. Furthermore, the segmentation results were in general consistent with the ground truth annotations, with complementary outcomes that can be further exploited by ensembling the results.  相似文献   
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IntroductionWith the changing landscape of tobacco products, the divide between cigarettes and cigars is obscured, so understanding adolescent reporting of cigar use is needed to improve best practices for surveillance, screening, and prevention/intervention. This study examined adolescents' reported cigar use and correlates of use.MethodsParticipants (N = 186) were 13–17 year old tobacco users participating in a prospective study of adolescent smoking behaviors. Measurement occurred at baseline and 24-months, and included demographics, nicotine dependence, tobacco use, and quit attempts. Cigar use was assessed as, “have you smoked a cigar in the last 30 days” and by brand specific use in the past 30 days.FindingsCigar use was reported by 51 adolescents (27%), and increased to 76 (41%) when identifying by brand name. African Americans (32%) were more likely to smoke cigars than whites (10%, p < .01), Asian/Pacific Islanders (3%, p = .04), and multiracial participants (24%, p = .05). Cigarette-only users smoked more per day (p = .04) and had higher cotinine levels (p = .05) than cigar users. Number of prior quit attempts (p = .84) did not differ by group. Group differences in addiction were found between cigar users and cigarette only users (p < .01). At 24 months, more baseline cigar users were tobacco abstinent than cigarette only users (16% versus 7%, p < 0.01, respectively).ConclusionsAssessment of brand-specific cigars nearly doubled the reporting among adolescent users. Cigar users differed from cigarette-only users in consumption and likelihood of abstinence at 24-months. For more accurate surveillance and to inform treatment considerations, surveys of adolescent tobacco use should include cigars, including brand names, in the assessment strategy.  相似文献   
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Despite a population of nearly 60 million, there is currently not a single interventional radiologist in Tanzania. Based on an Interventional Radiology (IR) Readiness Assessment, the key obstacles to establishing IR in Tanzania are the lack of training opportunities and limited availability of disposable equipment. An IR training program was designed and initiated, which relies on US-based volunteer teams of IR physicians, nurses, and technologists to locally train radiology residents, nurses, and technologists. Preliminary results support this strategy for addressing the lack of training opportunities and provide a model for introducing IR to other resource-limited settings.  相似文献   
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Severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) has a high death rate in patients with comorbidities or in an immunocompromised state. We report a mild and attenuated SARS CoV-2 infection in a patient who is 17 months post stem cell transplantation and maintained on the JAK/STAT inhibitor ruxolitinib, a proposed novel therapy for SARS CoV-2 pneumonia.  相似文献   
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ObjectiveObesity has reached epidemic proportions in the US. Physical activity is an important component of obesity reduction, but little is known about contemporary exercise levels among overweight/obese American adults. In this study, we compared current physical activity levels in overweight and obese US adults to those of normal weight individuals as well as ascertained which sociodemographic factors influence the meeting of physical activity recommendations in these three groups.MethodsWe used national data from 2015 and 2017 Behavioral Risk Factor Surveillance System surveys (n = 726,075). Bivariate analyses were conducted to determine unadjusted physical activity levels in normal weight, overweight, and obese adults. We fit multinomial logistic models to identify associations between sociodemographic factors and meeting physical activity recommendations in our study population.ResultsAround 45% of overweight and 57% of obese adults failed to meet physical activity guidelines compared to 41% of normal weight adults. Age, sex, and race were significantly associated with physical activity levels for both overweight and obese adults. In overweight and obese individuals, associations between sociodemographic factors and physical activity were more similar between the two comparisons of insufficiently active (IA) versus active (A)/highly active (HA) and A versus HA but quite different to those in the inactive (IN) versus IA/A/HA comparison.ConclusionsFuture physical activity interventions should be aimed at increasing the number of overweight and obese US adults who meet physical activity guidelines as well as targeted towards specific sociodemographic groups within the overweight/obese population with low exercise levels.  相似文献   
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BackgroundAlthough left atrial (LA) mechanical dysfunction in heart failure with preserved ejection fraction (HFpEF) is associated with poor clinical outcomes, the influence of LA myopathy on temporal changes in cardiovascular biomarkers is unclear.Methods and ResultsWe evaluated biomarker correlates of LA myopathy, as defined by reduced LA strain, and the associations of LA strain with longitudinal changes in biomarkers among participants in the Phosphodiesterase-5 Inhibition to Improve Clinical Status and Exercise Capacity in Heart Failure with Preserved Ejection Fraction (RELAX) trial. LA speckle-tracking was performed on baseline echocardiograms of RELAX participants to measure LA reservoir and LA contractile strain. Of the 216 RELAX participants, 169 (78%) had measurable LA strain and biomarker data. Participants with LA reservoir strain below median (13.5%, interquartile range: 10%–22.5%) were older, more likely to have atrial fibrillation, and had higher jugular venous pressure (P < .05 for all). At baseline, higher levels of endothelin-1, N-terminal pro–B-type natriuretic peptide (NT-proBNP), and troponin I were independently associated with lower LA reservoir and contractile strain (Padjusted < .05 for all comparisons). Higher LA reservoir strain (β coefficient per 1-unit increase: −21.2, 95% CI: −38.8, −3.7; P = .02) was independently associated with reduction in NT-proBNP at 24 weeks.ConclusionIn HFpEF, LA myopathy is characterized by elevation in biomarkers of neurohormonal activation and myocardial necrosis. Lower LA function is associated with continued elevation in NT-proBNP over time, suggesting that LA myopathy is associated with persistent congestion in HFpEF.  相似文献   
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