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排序方式: 共有1811条查询结果,搜索用时 31 毫秒
61.
Matthew J. O’Brien Ji Young Lee Mercedes R. Carnethon Ronald T. Ackermann Maria C. Vargas Andrew Hamilton Nivedita Mohanty Sarah S. Rittner Jessica N. Park Amro Hassan David R. Buchanan Lei Liu Joseph Feinglass 《PLoS medicine》2016,13(7)
BackgroundIn 2015, the United States Preventive Services Task Force (USPSTF) recommended targeted screening for prediabetes and diabetes (dysglycemia) in adults who are aged 40 to 70 y old and overweight or obese. Given increasing prevalence of dysglycemia at younger ages and lower body weight, particularly among racial/ethnic minorities, we sought to determine whether the current screening criteria may fail to identify some high-risk population subgroups.ConclusionsTargeted diabetes screening based on new USPSTF criteria may detect approximately half of adult community health center patients with undiagnosed dysglycemia and proportionately fewer racial/ethnic minorities than whites. Future research is needed to estimate the performance of these screening criteria in population-based samples. 相似文献
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Alinne Pereira de Castro Maria Regina Silveira Sartori da Silva Betania Ferraz Quirino Mercedes Maria da Cunha Bustamante Ricardo Henrique Krüger 《PloS one》2016,11(2)
The Cerrado, the largest savanna region in South America, is located in central Brazil. Cerrado physiognomies, which range from savanna grasslands to forest formations, combined with the highly weathered, acidic clay Cerrado soils form a unique ecoregion. In this study, high-throughput sequencing of ribosomal RNA genes was combined with shotgun metagenomic analysis to explore the taxonomic composition and potential functions of soil microbial communities in four different vegetation physiognomies during both dry and rainy seasons. Our results showed that changes in bacterial, archaeal, and fungal community structures in cerrado denso, cerrado sensu stricto, campo sujo, and gallery forest soils strongly correlated with seasonal patterns of soil water uptake. The relative abundance of AD3, WPS-2, Planctomycetes, Thermoprotei, and Glomeromycota typically decreased in the rainy season, whereas the relative abundance of Proteobacteria and Ascomycota increased. In addition, analysis of shotgun metagenomic data revealed a significant increase in the relative abundance of genes associated with iron acquisition and metabolism, dormancy, and sporulation during the dry season, and an increase in the relative abundance of genes related to respiration and DNA and protein metabolism during the rainy season. These gene functional categories are associated with adaptation to water stress. Our results further the understanding of how tropical savanna soil microbial communities may be influenced by vegetation covering and temporal variations in soil moisture. 相似文献
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Samarjit Patnaik Dipanwita Basu Noel Southall Seameen Dehdashti Kanny K. Wan Wei Zheng Marc Ferrer Mercedes Taylor Daniel A. Engel Juan Jose Marugan 《Bioorganic & medicinal chemistry letters》2019,29(9):1113-1119
Nonstructural protein 1 (NS1) plays a crucial function in the replication, spread, and pathogenesis of influenza virus by inhibiting the host innate immune response. Here we report the discovery and optimization of novel pyrazolopyridine NS1 antagonists that can potently inhibit influenza A/PR/8/34 replication in MDCK cells, rescue MDCK cells from cytopathic effects of seasonal influenza A strains, reverse NS1-dependent inhibition of IFN-β gene expression, and suppress the slow growth phenotype in NS1-expressing yeast. These pyrazolopyridines will enable researchers to investigate NS1 function during infection and how antagonists can be utilized in the next generation of treatments for influenza infection. 相似文献
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Jianing Fu Julien Zuber Mercedes Martinez Brittany Shonts Aleksandar Obradovic Hui Wang Sai-ping Lau Amy Xia Elizabeth E. Waffarn Kristjana Frangaj Thomas M. Savage Michael T. Simpson Suxiao Yang Xinzheng V. Guo Michelle Miron Takashi Senda Kortney Rogers Adeeb Rahman Megan Sykes 《Cell Stem Cell》2019,24(2):227-239.e8
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Kawana K Quayle AJ Ficarra M Ibana JA Shen L Kawana Y Yang H Marrero L Yavagal S Greene SJ Zhang YX Pyles RB Blumberg RS Schust DJ 《The Journal of biological chemistry》2007,282(10):7368-7375
Chlamydia trachomatis is an obligate intracellular pathogen that can persist in the urogenital tract. Mechanisms by which C. trachomatis evades clearance by host innate immune responses are poorly described. CD1d is MHC-like, is expressed by epithelial cells, and can signal innate immune responses by NK and NKT cells. Here we demonstrate that C. trachomatis infection down-regulates surface-expressed CD1d in human penile urethral epithelial cells through proteasomal degradation. A chlamydial proteasome-like activity factor (CPAF) interacts with the CD1d heavy chain, and CPAF-associated CD1d heavy chain is then ubiquitinated and directed along two distinct proteolytic pathways. The degradation of immature glycosylated CD1d was blocked by the proteasome inhibitor lactacystin but not by MG132, indicating that degradation was not via the conventional proteasome. In contrast, the degradation of non-glycosylated CD1d was blocked by lactacystin and MG132, consistent with conventional cellular cytosolic degradation of N-linked glycoproteins. Immunofluorescent microscopy confirmed the interruption of CD1d trafficking to the cell surface, and the dislocation of CD1d heavy chains into both the cellular cytosol and the chlamydial inclusion along with cytosolic CPAF. C. trachomatis targeted CD1d toward two distinct proteolytic pathways. Decreased CD1d surface expression may help C. trachomatis evade detection by innate immune cells and may promote C. trachomatis persistence. 相似文献