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151.
The emergence of SARS-CoV-2 triggering the COVID-19 pandemic ranks as arguably the greatest medical emergency of the last century. COVID-19 has highlighted health disparities both within and between countries and will leave a lasting impact on global society. Nonetheless, substantial investment in life sciences over recent decades has facilitated a rapid scientific response with innovations in viral characterization, testing, and sequencing. Perhaps most remarkably, this permitted the development of highly effective vaccines, which are being distributed globally at unprecedented speed. In contrast, drug treatments for the established disease have delivered limited benefits so far. Innovative and rapid approaches in the design and execution of large-scale clinical trials and repurposing of existing drugs have saved many lives; however, many more remain at risk. In this review we describe challenges and unmet needs, discuss existing therapeutics, and address future opportunities. Consideration is given to factors that have hindered drug development in order to support planning for the next pandemic challenge and to allow rapid and cost-effective development of new therapeutics with equitable delivery.  相似文献   
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OBJECTIVE: This retrospective study investigated the specificity of restricted water diffusion for the diagnosis of brain abscess. Two of five rim-enhancing brain masses with restricted water diffusion (apparent diffusion coefficient of 0.79 [10(-3) mm(2)/sec] or less) were brain abscesses, but diagnoses in the other cases were metastatic squamous cell carcinoma (two cases) and radiation necrosis. CONCLUSION: Although an important diagnostic sign, restricted water diffusion is not specific for brain abscess.  相似文献   
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BackgroundResearch indicates a possible relationship between adolescent depressive symptoms and physical activity, yet few studies have examined whether trajectories of adolescent physical activity differ among adolescents with and without elevated depressive symptoms.PurposeThis study documented change in physical activity from ages 12–17 years among youth with and without elevated depressive symptoms, and examined the influences of key family, physiological, and demographic covariates on activity patterns.MethodsData were from 371 youth. The sample was 50% female; 76% White, 12% African American, 4% Hispanic, 2% Asian, 2% American Indian, and 4% other or mixed races. Mean age was 12.05 years (SD = 1.63) at Time 1. Latent growth curve modeling (LGM), a cohort-sequential design, and a multiple-group design by level of depressive symptoms were employed.ResultsAdolescent physical activity declined significantly from ages 12–17 for those with and without elevated depressive symptoms. Adolescents with elevated symptoms had lower initial levels of physical activity than individuals without. For youth with low depressive symptoms, male sex and parental support of physical activity were related to higher initial levels of physical activity. For youth with elevated depressive symptoms, male sex, being White, and parental support were related to higher initial levels of physical activity. Additionally, for both groups, increases in parent physical activity were related to less of a decline in adolescent physical activity trajectories.ConclusionsFindings highlight the importance of parental support in promoting physical activity among adolescents with and without elevated depressive symptoms.  相似文献   
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Purpose  

This study was designed to assess the utility of the scarf osteotomy in the management of symptomatic adolescent hallux valgus.  相似文献   
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