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Separation and simultaneous quantitation of PGF2α and its epimer 8-iso-PGF2α using modifier-assisted differential mobility spectrometry tandem mass spectrometry

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Acta Pharmaceutica Sinica B 2018年第2期8卷 228-234页

作者： Chunsu Liang Hui Sun Xiangjun Meng Lei Yina J.Paul Fawcett huaidong yu Ting Liu Jingkai Gu Research Center for Drug Metabolism School of Life Sciences Jilin University School of Pharmacy University of Otago Shanghai AB Sciex Analytical Instrument Trading Co. Ltd.

Because many therapeutic agents are contaminated by epimeric impurities or form epimers as a result of metabolism, analytical tools capable of determining epimers are increasingly in demand. This article is a proof-of-principle report of a novel DMS–MS/MS method to separate and simultaneously quantify epimers, taking PGF2α and its 8-epimer, 8-iso-PGF2α, as an example. Good accuracy and precision were achieved in the range of 10–500 ng/m L with a run time of only 1.5 min. Isopropanol as organic modifier facilitated a good combination of sensitivity and separation. The method is the first example of the quantitation of epimers without chromatographic separation.

关键词： Differential mobility spectrometry Mass spectrometry Epimer PGF2α 8-iso-PGF2α

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超声冲击处理对灰铸铁焊接冷裂纹影响

焊接学报 2007年第11期28卷 78-80,84页

作者：严铿聂洁于怀东徐律江苏科技大学先进焊接技术省级重点实验室江苏镇江212003

采用HT150,以焊接冷裂纹三要素中的拘束应力和淬硬组织因素为研究方向,用评定铸铁冷裂纹敏感性的直Y形坡口焊接裂纹试验法,研究了超声冲击处理对焊接冷裂纹的影响。结果表明,焊后通过对焊缝进行全覆盖超声冲击,一方面可以大幅度改善焊... 详细信息

采用HT150,以焊接冷裂纹三要素中的拘束应力和淬硬组织因素为研究方向,用评定铸铁冷裂纹敏感性的直Y形坡口焊接裂纹试验法,研究了超声冲击处理对焊接冷裂纹的影响。结果表明,焊后通过对焊缝进行全覆盖超声冲击,一方面可以大幅度改善焊接结构的残余应力,经超声冲击处理后的试样焊缝测量点的残余应力R1分别为-53,-57MPa,R2分别为-37,-80MPa;另一方面可以加速焊缝石墨球化过程,消除半熔化区白口组织。因此焊后合理的超声冲击处理能够从拘束应力和淬硬组织两方面抑制焊接结构冷裂纹的产生。

关键词：超声冲击处理残余应力焊接冷裂纹

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锰离子对Fenton反应的影响

武汉大学学报（理学版） 2006年第4期52卷 453-456页

作者：于怀东项念杨扬邹国林武汉大学生命科学学院湖北武汉430072

Fenton反应是生物体内产生羟基自由基(.OH)的主要反应.Mn2+在体外可以参与类似反应生成.OH.在此基础上,本文利用自旋捕捉-ESR技术比较了Mn2+参与类Fenton反应(Fenton-like reaction)与Fe2+参与Fenton反应的能力,利用芳环羟基化(aromatic... 详细信息

Fenton反应是生物体内产生羟基自由基(.OH)的主要反应.Mn2+在体外可以参与类似反应生成.OH.在此基础上,本文利用自旋捕捉-ESR技术比较了Mn2+参与类Fenton反应(Fenton-like reaction)与Fe2+参与Fenton反应的能力,利用芳环羟基化(aromatic hydroxylation)反应-高效液相色谱法检测了Mn2+对Fe2+参与的Fenton反应的影响.利用电泳技术检测了上述反应产生的.OH对质粒DNA的损伤情况.结果显示,在实验条件下,Mn2+与过氧化氢(H2O2)反应产生.OH的能力仅为相同条件下Fe2+的5%左右.但Mn2+可以在Fenton反应中明显促进.OH的产生.

关键词：锰羟基自由基类Fenton反应电子顺磁共振光谱氧化胁迫

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高管团队背景特征与券商效率的相关性分析

淮南师范学院学报 2019年第3期21卷 46-51页

作者：陈燕玲余怀东安徽大学经济学院

利用我国2010年12月31日之前在A股上市的17家上市券商2011~2017年的面板数据构建计量模型,研究高管团队背景特征对券商效率的影响。研究结果表明:高管团队背景特征与券商效率存在相关性关系。具体来说,高管团队成员的平均年龄、在本公... 详细信息

利用我国2010年12月31日之前在A股上市的17家上市券商2011~2017年的面板数据构建计量模型,研究高管团队背景特征对券商效率的影响。研究结果表明:高管团队背景特征与券商效率存在相关性关系。具体来说,高管团队成员的平均年龄、在本公司内或者金融行业的工作经历对券商效率都有促进作用;高管团队成员的平均学历水平对券商效率具有抑制作用;高管团队成员性别构成与券商效率并不存在相关性关系。

关键词：高管团队背景特征券商效率 DEA-tobit模型

Illumina-Based Analysis of Bulk and Rhizosphere Soil Bacterial Communities in Paddy Fields Under Mixed Heavy Metal Contamination

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Pedosphere 2017年第3期27卷 569-578页

作者： HE huaidong LI Waichin Riqing yu YE Zhihong State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources School of Life Sciences Sun Yat-sen University Department of Science and Environmental Studies The Education University of Hong Kong Department of Biology The University of Texas at Tyler

There is an increasing concern about rice （Oryza sativa L.） soil microbiomes under the influence of mixed heavy metal contamina- tion. We used the high-throughput Illumina MiSeq sequencing approach to explore the bacterial diversity and community composition of soils in four paddy fields, exhibiting four degrees of mixed heavy metal （Cd, Pb and Zn） pollution, and examined the effects of these metals on the bacterial communities. Our results showed that up to 2 104 to 4 359 bacterial operational taxonomic units （OTUs） were found in the bulk and rhizosphere soils of the paddy fields, with the dominant bacterial phyla （greater than 1% of the overall community） including Proteobacteria, Actinobacteria, Firmicutes, Acidobacteria, Gemmatimonadetes, Chlorofiexi, Bacteroidetes and Nitrospirem. A number of rare and candidate bacterial groups were also detected, and Saprospirales, HOC36, SC-I-84 and Anaerospora were rarely detected in rice paddy soils. Venn diagram analysis showed that 174 bacterial OTUs were shared among the bulk soils with four pollution degrees. Rice rhizosphere soils displayed higher bacterial diversity indices （ACE and Chao 1） and more unique OTUs than bulk soils. Total Cd and Zn in the soils were significantly negatively correlated with ACE and Chao 1, respectively, and the Mantel test suggested that total Pb, total Zn, pH, total nitrogen and total phosphorus significantly affected the community structure. Overall, these results provided baseline data for the bacterial communities in bulk and rhizosphere soils of paddy fields contaminated with mixed heavy metals.

关键词： bacterial diversity community structure Illuming MiSeq sequencing approach long-term contamination paddy soil

Prevalence and Risk Factors for Chronic Obstructive Pulmonary Disease Among Adults Aged 50 and Above-10 CKB Study Areas,China,2020–2021

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China CDC weekly 2024年第43期6卷 1126-1131页

作者： Wei yu Yongbing Lan Dianjianyi Sun Pei Pei Ling Yang Yiping Chen huaidong Du Yingcai Yang Dan Schmidt Junshi Chen Zhengming Chen Jun Lyu Liming Li Canqing yu Department of Epidemiology&Biostatistics School of Public HealthPeking UniversityBeijingChina Peking University Center for Public Health and Epidemic Preparedness&Response BeijingChina Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijingChina Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU) Nuffield Department of Population HealthUniversity of OxfordOxfordUnited Kingdom Shinan District Center for Disease Control and Prevention Qingdao CityShandong ProvinceChina China National Center for Food Safety Risk Assessment BeijingChina State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijingChina.

What is already known about this topic?The prevalence of COPD in Chinese individuals aged 50 years and above was obviously higher than that in younger adults,but the risk factors for this age group were *** is added by this report?The prevalence was estimated at 12.8%and 5.7%for males and females over 50 in 2020–2021,with confirmed risk factors of cigarette smoking,a family history of respiratory diseases,respiratory symptoms,and a history of cough or respiratory diseases during *** are the implications for public health practice?The findings may help clinicians and the public identify individuals at high risk of COPD and take targeted measures in a timely manner.

关键词： respiratory diseases prevalence

The Association Between Preserved Ratio Impaired Spirometry and Mortality –– 10 CKB Study Areas, China, 2004–2022

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China CDC weekly 2024年第43期6卷 1120-1125,I0003页

作者： Yalei Ke Xinyi Zhang Dianjianyi Sun Pei Pei huaidong Du Yiping Chen Ling Yang Xiaoming Yang Kang Wang Junshi Chen Zhengming Chen Jun Lv Liming Li Canqing yu Department of Epidemiology and Biostatistics School of Public HealthPeking University Health Science CenterBeijingChina Peking University Center for Public Health and Epidemic Preparedness&Response BeijingChina Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijingChina Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU) Nuffield Department of Population HealthUniversity of OxfordOxfordUK Shibei Center for Disease Control and Prevention Qingdao CityShandong ProvinceChina China National Center for Food Safety Risk Assessment BeijingChina State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijingChina.

What is already known about this topic?China has the world’s most significant public health and economic burden of chronic respiratory ***,the association between preserved ratio impaired spirometry(PRISm)and mortality risk is *** is added by this report?The PRISm group exhibited a 37%higher risk of allcause mortality than the normal group,and the risks of death from cardiovascular diseases,neoplasms,respiratory diseases,and infectious and parasitic diseases were also increased in ***,the presence of respiratory symptoms or disease was associated with an increased risk of mortality in *** are the implications for public health practice?It is imperative to enhance public awareness of PRISm and to implement measures to facilitate the regression of PRISm toward normal lung function.

关键词： function impaired neoplasms

论唐传奇的文化精神——兼论中国古代小说文体独立的文化内涵

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江海学刊 2009年第3期 195-200页

作者：吴怀东余恕诚安徽大学中文系安徽师范大学中国诗学研究中心

唐代士人将信将疑、半信半疑的宗教信仰,使得他们在一定程度上摆脱了宗教的束缚;唐代科举制度的大力施行,使得士人从政治体制中得到了一定程度的解放,思想的解放和人身的自由使他们获得了一定的个人自主性,培养了对世俗现实生活的关怀... 详细信息

唐代士人将信将疑、半信半疑的宗教信仰,使得他们在一定程度上摆脱了宗教的束缚;唐代科举制度的大力施行,使得士人从政治体制中得到了一定程度的解放,思想的解放和人身的自由使他们获得了一定的个人自主性,培养了对世俗现实生活的关怀和兴趣,普通、个体的人的生活获得了独立的价值,造成了传奇现实性和世俗性的文化精神;传奇从一般史书和志怪中独立出来,获得了与欧洲近代小说相同的文学创作性质,唐传奇表现的社会生活具有广泛性,刻画的人物具有复杂性,叙事具有自觉的虚构性。

关键词：小说传奇现实性世俗性

Association of physical activity with risk of chronic kidney disease in China:A population-based cohort study

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Journal of Sport and Health Science 2024年第2期13卷 204-211页

作者： Kexiang Shi yunqing Zhu Jun Lv Dianjianyi Sun Pei Pei huaidong Du Yiping Chen Ling Yang Bing Han Rebecca Stevens Junshi Chen Zhengming Chen Liming Li Canqing yu China Kadoorie Biobank collaborative group Department of Epidemiology&Biostatistics School of Public HealthPeking University Health Science CenterBeijing 100191China Peking University Center for Public Health and Epidemic Preparedness&Response Beijing 100191China Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijing 100191China Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU) Nuffield Department of Population HealthUniversity of OxfordOxford OX37LFUK Medical Research Council Population Health Research Unit at the University of Oxford Oxford OX37LFUK NCDs Prevention and Control Department Henan Center for Disease Control and PreventionZhengzhou 450016China China National Center for Food Safety Risk Assessment Beijing 100022China 不详

Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is *** aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in ***:The study included 475,376 adults from the China Kadoorie Biobank aged 30-79 years during 2004-2008 at *** interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4 groups based on *** regression was used to analyze the association between PA and CKD ***:During a median follow-up of 12.1 years,5415 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD)cases and 362 incident hypertensive nephropathy(HTN)*** PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92)for incident CKD in the highest quartile of total PA as compared with participants in the lowest *** results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN *** nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94),and 0.85(0.76-0.95)in the highest quartile,***:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent.

关键词： Chronic kidney disease Domain Intensity Physical activity