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861.
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Cerebrospinal fluid Th1/Th2 cytokine profiles in children with enterovirus 71‐associated meningoencephalitis
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Huajun Li Shuxian Li Jianfeng Zheng Chunyan Cai Bin Ye Jun Yang Zhimin Chen 《Microbiology and immunology》2015,59(3):152-159
Enterovirus 71 (EV71) infection can cause severe neurological complications including meningoencephalitis (ME) in some patients with hand, foot and mouth disease (HFMD). However, to date no studies have reported changes in cytokine concentrations and their correlations with clinical variables in patients with ME following EV71 infection. In this study, responses of Th1/Th2 cytokine, including IL‐2, IL‐4, IL‐6, IL‐10, TNF‐α and IFN‐γ, in cerebrospinal fluid (CSF) from patients with EV71‐related HFMD with ME and patients with febrile convulsions (FC) were analyzed using cytometric bead array technology. It was found that CSF IL‐6 and IFN‐γ concentrations were significantly higher in patients with EV71‐related ME than in those with FC. Additionally, both CSF IL‐6 and IFN‐γ concentrations were correlated with CSF cytology, fever duration and duration of hospital stay. More interestingly, a positive correlation between CSF IL‐6 and IFN‐γ concentrations was observed. Finally, receiver operating characteristic analysis revealed that when a cutoff value of 9.40 pg/mL was set for IL‐6, the sensitivity and specificity were 84.5% and 85.5%, respectively, for discriminating EV71‐related ME from FC. In conclusion, IL‐6 and IFN‐γ may be associated with EV71‐induced neuropathology. 相似文献
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A wavelet‐based approach to evaluate the roles of structural and functional landscape heterogeneity in animal space use at multiple scales
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Xinping Ye Tiejun Wang Andrew K. Skidmore Daniel Fortin Guillaume Bastille‐Rousseau Lael Parrott 《Ecography》2015,38(7):740-750
The functional relationship between habitat utilization and landscape spatial heterogeneity is fundamental to understanding the spatial nature of animal distribution across scales. Although structural and functional properties of landscape spatial heterogeneity can have different consequences for animal species, few studies have explicitly considered both forms of heterogeneity, partly due to the lack of general methods for direct assessment of scale‐specific associations between variables. We present a wavelet‐based approach to evaluate the roles of structural and functional landscape spatial heterogeneity in animal space use at multiple spatial scales. As a case study, we examined scale‐specific space use patterns of American black bears Ursus americanus in response to structural and functional spatial heterogeneity as well as spatial patterns of vegetation age‐classes in a Canadian boreal forest. We found strong differences in the effects of structural and functional spatial heterogeneity and the scales at which they are associated with the patterns of habitat use by black bears. Functional heterogeneity alone affected space use at 800 and 1600‐m scales, but had significant effects when interacting with structural heterogeneity at 400, 800, and 1600‐m scales. Compared with male bears, female black bears were most sensitive to patterns of forage abundance at intermediate scales, or more specifically, in young and regenerating forests that provide abundant soft mast in boreal forests. Our study highlights the importance of accounting for scale‐dependent properties of (structural and functional) spatial heterogeneity in assessing the ecological effects of landscape components and the effectiveness of the wavelet transform technique in identifying such scale‐specific relationships. 相似文献
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Longbiao Guo Jie Qiu Zujing Han Zihong Ye Chao Chen Chuanjun Liu Xiufang Xin Chu‐Yu Ye Ying‐Ying Wang Hongqing Xie Yu Wang Jiandong Bao She Tang Jie Xu Yijie Gui Fei Fu Weidi Wang Xingchen Zhang Qianhua Zhu Xuanmin Guang Chongzhi Wang Haifeng Cui Daguang Cai Song Ge Gerald A. Tuskan Xiaohan Yang Qian Qian Sheng Yang He Jun Wang Xue‐Ping Zhou Longjiang Fan 《The Plant journal : for cell and molecular biology》2015,83(4):600-609
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摘要:【目的】研究温度以及返回液添加量对体系中氧化效果以及金(Au)氰化浸出率的影响。【方法】针对某高硫高砷金精矿建立了一套连续生物预氧化体系(氧化时间6 d),比较不同的温度(40℃和45℃)和返回液添加量(0和600mL)对生物预氧化效果的影响:间隔8 h连续测定氧化体系中的氧化液、氧化渣以及氰化渣中的总Fe、总S、总As以及SO4
2-和Au含量;并用16S rRNA基因克隆文库的方法对体系中的浸矿菌群结构进行分析。【结果】结果显示,提高温度和添加氧化返回液都会改变体系:升高温度在一定程度上提高了体系的氧化程度,主要表现为显著降低了尾渣中总铁、总硫含量,显著提高了尾渣中的S6 + 比例,并且降低前三槽氧化体系的耗碱量;投加返回液则会降低体系的氧化程度,主要表现为显著提高了尾渣金品位和铁含量,显著降低了尾渣中的S6 + 以及Au 浸出率;Dissimilarity和DCA结果表明温度变化对体系的影响更为显著;氧化过程中的Au 浸出率、硫氧化率以及As 去除率,三者互为显著正相关;克隆文库结果显示,该浸矿菌群主要包括3类细菌: Acidithiocacillus caldu (71%)、Leptospirillum ferriphilum (23%)和Sulfobacillus thermosulfidooxidans(6%),基于97%相似性的OTU覆盖率达93.67%。【结论】研究结果表明,相对于添加返回液,温度变化会更显著的改变体系反应效率。提高体系温度有利于矿物的氧化,而添加返回液会降低Au浸出率。本文首次研究了连续生物预氧化过程中温度梯度和返回液添加对体系的影响,本研究结果对中温生物预氧化工业生产的工艺优化、降低工业运行成本具有重要的指导意义。 相似文献