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Hepatitis B virus taxonomy and hepatitis B virus genotypes 被引量:44
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作者 Stephan schaefer 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第1期14-21,共8页
Hepatitis B virus(HBV) is a member of the hepadnavirus family.Hepadnaviruses can be found in both mammals(orthohepadnaviruses) and birds(avihepadnaviruses).The genetic variability of HBV is very high.There are eight g... Hepatitis B virus(HBV) is a member of the hepadnavirus family.Hepadnaviruses can be found in both mammals(orthohepadnaviruses) and birds(avihepadnaviruses).The genetic variability of HBV is very high.There are eight genotypes of HBV and three clades of HBV isolates from apes that appear to be additional genotypes of HBV.Most genotypes are now divided into subgenotypes with distinct virological and epidemiological properties.In addition,recombination among HBV genotypes increases the variability of HBV.This review summarises current knowledge of the epidemiology of genetic variability in hepadnaviruses and,due to rapid progress in the field,updates several recent reviews on HBV genotypes and subgenotypes. 展开更多
关键词 Orthohepadnavirus Avihepadnavirus Hepatitis B virus Genotype Subgenotype Recombination
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Growth of Large-Area Single- and Bi-Layer Graphene by Controlled Carbon Precipitation on Polycrystalline Ni Surfaces 被引量:23
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作者 Alfonso Reina Stefan Thiele +4 位作者 Xiaoting Jia Sreekar Bhaviripudi Mildred S.Dresselhaus Juergen A.schaefer Jing Kong 《Nano Research》 SCIE EI CSCD 2009年第6期509-516,共8页
We report graphene films composed mostly of one or two layers of graphene grown by controlled carbon precipitation on the surface of polycrystalline Ni thin films during atmospheric chemical vapor deposition(CVD).Cont... We report graphene films composed mostly of one or two layers of graphene grown by controlled carbon precipitation on the surface of polycrystalline Ni thin films during atmospheric chemical vapor deposition(CVD).Controlling both the methane concentration during CVD and the substrate cooling rate during graphene growth can signifi cantly improve the thickness uniformity.As a result,one-or two-layer graphene regions occupy up to 87%of the fi lm area.Single layer coverage accounts for 5%11%of the overall fi lm.These regions expand across multiple grain boundaries of the underlying polycrystalline Ni fi lm.The number density of sites with multilayer graphene/graphite(>2 layers)is reduced as the cooling rate decreases.These fi lms can also be transferred to other substrates and their sizes are only limited by the sizes of the Ni fi lm and the CVD chamber.Here,we demonstrate the formation of fi lms as large as 1 in^(2).These fi ndings represent an important step towards the fabrication of large-scale high-quality graphene samples. 展开更多
关键词 GRAPHENE chemical vapor deposition nickel catalyst carbon nanomaterials
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北京市PM2.5对DNA的氧化性损伤规律分析 被引量:14
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作者 胡颖 邵龙义 +3 位作者 schaefer K 王静 Suppan P 王建英 《中国环境科学》 EI CAS CSCD 北大核心 2013年第10期1863-1868,共6页
运用质粒DNA损伤评价法,在北京市2010年6月至2011年6月全年的大气PM2.5样品中,选取每月的2个样品(包括正常和雾霾天气),共24个样品进行实验,分析其氧化性损伤能力的变化规律及其与采样条件的相互关系.结果表明,北京市大气颗粒物全样的... 运用质粒DNA损伤评价法,在北京市2010年6月至2011年6月全年的大气PM2.5样品中,选取每月的2个样品(包括正常和雾霾天气),共24个样品进行实验,分析其氧化性损伤能力的变化规律及其与采样条件的相互关系.结果表明,北京市大气颗粒物全样的氧化性损伤能力等于或略大于相应的水溶组分,说明颗粒物氧化性损伤能力多来自于水溶组分,大气颗粒物对DNA损伤率呈现在50,100,150,200 g/mL剂量水平下依次递增的规律,即随剂量的增加而增加;雾霾天气下DNA损伤率出现高值;4月和6月的DNA损伤率在全年中较高.其他月份正常天气条件下损伤率均较低,在200 g/mL剂量下损伤率基本低于50%;损伤率与环境平均温度和湿度呈正相关,与平均大气压强和日平均风速呈负相关,相关性大小顺序为:环境平均温度>平均大气压强>平均湿度>日平均风速. 展开更多
关键词 PM2 5 质粒DNA 北京市
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多/全电飞机用高速开关磁阻起动/发电机优化控制(英文) 被引量:10
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作者 宋受俊 刘卫国 Uwe schaefer 《电工技术学报》 EI CSCD 北大核心 2010年第4期44-52,共9页
介绍了开关磁阻起动/发电(SRS/G)系统的应用背景,对系统的性能要求进行了描述,并给出了一台30kW开关磁阻电机(SRM)的定、转子叠片结构及尺寸。基于以上工作,对SRM的优化控制方法进行了研究:在起动阶段,SRM运行在电动状态,以平均转矩最... 介绍了开关磁阻起动/发电(SRS/G)系统的应用背景,对系统的性能要求进行了描述,并给出了一台30kW开关磁阻电机(SRM)的定、转子叠片结构及尺寸。基于以上工作,对SRM的优化控制方法进行了研究:在起动阶段,SRM运行在电动状态,以平均转矩最大化作为优化目标,对包括解析、数值及浮角在内的三种优化控制方法进行了深入的研究,并对它们的优化结果进行了详细的比较及分析;在发电阶段,SRM运行在发电状态,以特定输出功率下的系统效率最大化作为优化目标,得到了使主功率损耗最小的优化励磁角。 展开更多
关键词 多/全电飞机(M/A EA) 集成起动/发电机(IS/G) 开关磁阻电机(SRM) 优化励磁 平均转矩 效率最大化
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尿动力学质量控制(Ⅱ):典型信号模式的识别及其在实时定性质量控制中的作用 被引量:10
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作者 廖利民 Werner schaefer 《中华泌尿外科杂志》 CAS CSCD 北大核心 2006年第5期300-303,共4页
目的通过分析充盈和排尿期膀胱测压数据识别和建立典型信号模式(TSP),并验证其在实时定性质量控制中的作用。方法对181例下尿路症状成年男性进行582次膀胱压力测定,识别和描述充盈和排尿期的膀胱压(Pves)、腹压(Pabd)和逼尿肌压(Pdet)... 目的通过分析充盈和排尿期膀胱测压数据识别和建立典型信号模式(TSP),并验证其在实时定性质量控制中的作用。方法对181例下尿路症状成年男性进行582次膀胱压力测定,识别和描述充盈和排尿期的膀胱压(Pves)、腹压(Pabd)和逼尿肌压(Pdet)的曲线信号模式;分别在膀胱充盈开始、充盈中、排尿开始、排尿中及排尿后比较上述曲线的TSP:信号的细微结构(模式Ⅰ)、信号对呼吸和说话或轻微移动的应答(模式Ⅱ)、信号对规则咳嗽的应答(模式Ⅲ),辨别逼尿肌不稳定、腹肌收缩和直肠运动导致的信号巨观改变(模式Ⅳ)。比较对应信号的符合率,对膀胱测压的TSP进行系统描述,以控制信号质量。结果充盈开始时,91.8%(534/582)曲线在Pves及Pabd具有相同的Ⅰ、Ⅱ型信号、为“活”信号;74.8%(435/582)对咳嗽的应答相同,仅3.1%(18/582)出现腹肌或直肠收缩产生的巨观改变。在充盈期,98.3%(572/582)的Pves及Pabd的Ⅰ型和Ⅱ型信号相同,98.5%(573/582)对咳嗽的应答相同或相似,8.3%(48/582)出现腹肌收缩,33.7%(196/582)逼尿肌不稳定,17.4%(101/582)直肠收缩。在排尿开始前,94.0%(547/582)的Pves及Pabd对咳嗽应答相同。排尿期91.2%(531/582)为“活”信号,95.2%(554/582)为典型逼尿肌收缩模式,2.1%(12/582)直肠收缩,15.3%(89/582)盆底松弛。排尿后,91.2%(531/582)仍为“活”信号,87.5%(509/582)Pves及Pabd对咳嗽的应答相同。结论TSP是尿动力学测定中进行实时定性质量控制的有力工具,熟悉和辨认所描述的TSP并与典型值范围结合可使质量控制具体化,具备可操作性。 展开更多
关键词 尿动力学 质量控制 典型信号模式
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Detailed Design of a High Speed Switched Reluctance Starter/Generator for More/All Electric Aircraft 被引量:10
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作者 宋受俊 刘卫国 +1 位作者 Dieter Peitsch Uwe schaefer 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第2期216-226,共11页
The basic concepts and advantages of more/all electric aircraft (M/AEA) are briefly addressed. The combined starter/generator (CS/G) system is introduced as a key technology to enable M/AEA. Some important perform... The basic concepts and advantages of more/all electric aircraft (M/AEA) are briefly addressed. The combined starter/generator (CS/G) system is introduced as a key technology to enable M/AEA. Some important performance requirements for CS/G system are obtained. Based on these requirements, a high speed switched reluctance machine (SRM) is designed to operate as a starter/generator. The entire design process is mainly divided into two stages: electromagnetic design and thermal design. In electromagnetic design stage, the electromagnetic structure and dimensions of the machine and the number of phase winding turns per pole are obtained; the topology and main technical details of the converter are briefly introduced as well. In thermal design stage, a liquid-cooling system is designed based on the thermal analysis of the machine. In the end, the performances of the designed SRM are basically verified by simulation. To get high performances, the exciting angles are optimized in two different operating modes respectively, and the optimized performances in the motoring mode are given as well. 展开更多
关键词 AIRCRAFT more/all electric aircraft combined starter/generator system reluctance motors electromagnetic design THERMALANALYSIS control optimization
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Variations in net litter nutrient input associated with tree species influence on soil nutrient contents in a subtropical evergreen broad-leaved forest 被引量:8
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作者 Lu Qiao Doug Allen schaefer Xiaoming Zou 《Chinese Science Bulletin》 SCIE EI CAS 2014年第1期46-53,共8页
The influence of tree species on soils has received much attention,but we know little about either the pattern and underlying mechanisms of net nutrient and carbon inputs under canopy for various tree species or the e... The influence of tree species on soils has received much attention,but we know little about either the pattern and underlying mechanisms of net nutrient and carbon inputs under canopy for various tree species or the effects of net nutrient input on soil nutrient contents.To address these issues,we selected three tree species with distinct leaf sizes and arranged litter traps around the target individuals to test what affected net nutrient and carbon inputs under canopy of target individuals,and how net nutrient inputs influenced soil nutrient contents.The results showed that net litter manganese(Mn)and lignin inputs were significantly different among these tree species,as well as soil exchangeable potassium(K),available iron(Fe)and available Mn.The results also revealed that the species with the smallest sized leaves may stimulate more net Mn and lignin inputs than the species with the largest sized leaves.At the same time,net nutrient inputs correlated with soil available Fe,while the ratio of lignin to nitrogen of net litter correlated with total phosphorus contents.These results demonstrated that litter production may be the main factor deciding net nutrient and carbon inputs under different tree species’canopy,which significantly differentiated soil iron’s availability. 展开更多
关键词 土壤养分含量 亚热带常绿阔叶林 树种 枯落物 输入 营养 养分投入 木质素
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尿动力学质量控制(Ⅰ):典型值范围的建立及其在实时定量质量控制中的作用 被引量:7
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作者 廖利民 Werner schaefer 《中华泌尿外科杂志》 CAS CSCD 北大核心 2006年第5期296-299,共4页
目的 通过分析尿动力学数据建立典型值范围(TVR),并验证其在实时定量质量控制中的作用.方法 对181例下尿路症状患者进行582次尿动力学测定,分析膀胱充盈前、开始和结束时以及排尿后的膀胱压(Pves)、腹压(Pabd)、逼尿肌压(Pdet... 目的 通过分析尿动力学数据建立典型值范围(TVR),并验证其在实时定量质量控制中的作用.方法 对181例下尿路症状患者进行582次尿动力学测定,分析膀胱充盈前、开始和结束时以及排尿后的膀胱压(Pves)、腹压(Pabd)、逼尿肌压(Pdet)、膀胱容积(MCC)、最大尿流率(Qmax)、排尿量(Vvoid)和膀胱顺应性(BC),计算各参数的平均数、标准差及中位数,建立各参数的TVR,对与TVR相关的各种技术错误进行分类,并举出范例.结果 初始静息状态下P ves、Pabd及Pdet的50%TVR分别为31~42、28~39及0~4 cm H2O(1 cm H2O=0.098kPa),相关技术错误被分为Ⅰ、Ⅱ和Ⅲ型,发生率分别为9.8%(57/582)、4.5%(26/582)和1.4%(8/582).MCC和BC的50%TVR分别为157~345 ml和26.6~70.8 ml/cm H2O;排尿期Qmax、Pdet.Qmax和V void的50%TVR分别为5.5~9.0 ml/s,57~92 cm H2O和167~315 ml.单纯尿流率测定中Qmax和V void各为8.0~9.2 ml/s和167~301 ml.排尿中和排尿末的技术错误分为Ⅳ、Ⅴ和Ⅵ型,发生率分别为0.7%(4/582)、1.9%(11/582)和1.4%(8/582).结论 TVR对于尿动力学数据的可靠性检查和质量控制是不可缺少的有效工具,可用于尿动力学测定过程中的实时定量质量控制. 展开更多
关键词 尿动力学 质量控制 典型值范围
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Cross-sectional and longitudinal studies on interaction between bladder compliance and outflow obstruction in men with benign prostatic hyperplasia 被引量:7
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作者 Li-Min Liao Werner schaefer 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第1期51-56,共6页
Aim: To explore the interaction between bladder compliance (BC) and bladder outflow obstruction (BOO) in men with benign prostatic hyperplasia (BPH) using cross-sectional and longitudinal studies. Methods: A t... Aim: To explore the interaction between bladder compliance (BC) and bladder outflow obstruction (BOO) in men with benign prostatic hyperplasia (BPH) using cross-sectional and longitudinal studies. Methods: A total of 181 men with BPH were recruited, and 100 of them were followed for one year. Cystometry was performed in a standing or a sitting position with 30 mL/min infusion. BC was manually corrected and defined. Obstruction coefficient (OCO), linear passive urethral resistance relation and international continence society (ICS) nomogram were used to diagnose BOO. The obstructed parameters were compared between the reduced BC group and the non-reduced group. BC was compared between the first investigation at the beginning of study and the second investigation at the end of study during the one-year follow-up period. Results: The group with reduced BC had increased OCO and linear passive urethral resistance relation. BC was significantly lower in the obstructed group (55.7 mL/cm water) than that in unobstructed and equivocal one (74.9 mL/cm water, P 〈 0.01). BC gradually reduced with the increased obstructed grade. There was a significantly weak negative correlation between BC and OCO (r = - 0.132, P 〈 0.01). Over the one-year follow-up period in the longitudinal study, BC for all men changed from 54.4 to 48.8 mL/cm water (P 〉 0.05), and BC for the group with BOO fell from 58.4 ± 70.1 to 46.5 ± 38.7 mL/cm water (P 〉 0.05). Conclusion: In men with BPH, a significant systematic decrease occurred in BC in the obstructed group and a significant systematic increase with urethral resistance occurred in the low BC group. A longitudinal study of the tendency of BC reduction in a group with BOO is necessary in the future. 展开更多
关键词 benign prostatic hyperplasia bladder compliance bladder outflow obstruction
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Copper toxicosis gene MURRl is not changed in Wilson disease patients with normal blood ceruloplasmin levels 被引量:5
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作者 Karl Heinz Weiss Uta Merle +3 位作者 Mark schaefer Peter Ferenci Joachim Fullekrug Wolfgang Stremmel 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第14期2239-2242,共4页
AIM: To analyze our Wilson disease patient cohort (n = 106) for alterations in the gene coding for MURR1. METHODS: Patients with an established diagnosis of Wilson disease but normal ceruloplasmin blood levels wer... AIM: To analyze our Wilson disease patient cohort (n = 106) for alterations in the gene coding for MURR1. METHODS: Patients with an established diagnosis of Wilson disease but normal ceruloplasmin blood levels were chosen for our study (n = 14). Patients with two known disease-causing mutations in the ATPTB gene were not included. The three exons of the human MURR1 gene were sequenced after amplification of the genomic DNA by polymerase chain reaction. RESULTS: Our study did not reveal any mutations leading to an amino acid change in the MURR1 sequence of Wilson disease patients. A polymorphism at 472 bp of the coding sequence could be confirmed. CONCLUSION: The MURRI gene plays no role in the pathogenesis of Wilson disease patients with normal serum ceruloplasmin levels. 展开更多
关键词 Wilson Disease ATPTB MURR1 COMMD1
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滑动多层磁共振成像对原发性卵巢癌分期的应用研究 被引量:6
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作者 张伶 王仁法 +4 位作者 Pache G 伍尧泮 schaefer O Langer M 关键 《影像诊断与介入放射学》 2010年第3期145-148,共4页
目的分析滑动多层磁共振成像(SMS-MRI)的技术特点,并探讨SMS-MRI在原发性卵巢癌分期中的价值。方法对15例卵巢癌患者术前行SMS-MRI扫描,扫描范围包括胸腹盆腔(从胸廓入口至盆底)。SMS-MRI扫描的主要序列有常规T_2WITSE序列、SMS-TIRM序... 目的分析滑动多层磁共振成像(SMS-MRI)的技术特点,并探讨SMS-MRI在原发性卵巢癌分期中的价值。方法对15例卵巢癌患者术前行SMS-MRI扫描,扫描范围包括胸腹盆腔(从胸廓入口至盆底)。SMS-MRI扫描的主要序列有常规T_2WITSE序列、SMS-TIRM序列和SMSFLASH 2D压脂增强序列。SMS-MRI图像由两位放射科医师随机单盲阅片后进行分期诊断,并将其结果与手术病理结果对照。观察内容包括:(1)肿瘤定位(单侧或双侧);(2)局部浸润:子宫输卵管或其他盆腔组织受侵;(3)腹膜转移;(4)淋巴结转移;(5)远处转移。结果 15例均经组织病理学证实,其中浆液性囊腺癌9例,黏液性囊腺癌2例,子宫内膜样癌2例,透明细胞癌和颗粒细胞癌各1例。手术病理分期为Ⅰ期0例,Ⅱ期2例,Ⅲ期10例,Ⅳ期3例。以手术病理结果为金标准,SMS-MRI对于原发性卵巢癌总的分期准确率为100%(15/15)。SMS-MRI在卵巢癌的定位诊断、子宫输卵管局部浸润和远处转移等方面的符合率均为100%。结论结合SMS技术的MRI可在保证图像质量的情况下,在较短的时间内一次性完成体部胸腹盆腔扫描,能较准确的完成卵巢癌原发灶和转移的侦测和分期,为卵巢癌分期诊断提供了一项新的影像诊断选择。 展开更多
关键词 磁共振成像 卵巢癌 分期 滑动多层技术
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High-fat diet and oral infection induced type 2 diabetes and obesity development under different genetic backgrounds 被引量:4
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作者 Iqbal M.Lone Nadav Ben Nun +3 位作者 Aya Ghnaim Arne S.schaefer Yael Houri-Haddad Fuad A.Iraqi 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第2期131-145,共15页
Background:Type 2 diabetes(T2D)is an adult-onset and obese form of diabetes caused by an interplay between genetic,epigenetic,and environmental components.Here,we have assessed a cohort of 11 genetically different col... Background:Type 2 diabetes(T2D)is an adult-onset and obese form of diabetes caused by an interplay between genetic,epigenetic,and environmental components.Here,we have assessed a cohort of 11 genetically different collaborative cross(CC)mouse lines comprised of both sexes for T2D and obesity developments in response to oral infection and high-fat diet(HFD)challenges.Methods:Mice were fed with either the HFD or the standard chow diet(control group)for 12 weeks starting at the age of 8 weeks.At week 5 of the experiment,half of the mice of each diet group were infected with Porphyromonas gingivalis and Fusobacterium nucleatum bacteria strains.Throughout the 12-week experimental period,body weight(BW)was recorded biweekly,and intraperitoneal glucose tolerance tests were performed at weeks 6 and 12 of the experiment to evaluate the glucose tolerance status of mice.Results:Statistical analysis has shown the significance of phenotypic variations between the CC lines,which have different genetic backgrounds and sex effects in different experimental groups.The heritability of the studied phenotypes was estimated and ranged between 0.45 and 0.85.We applied machine learning methods to make an early call for T2D and its prognosis.The results showed that classification with random forest could reach the highest accuracy classification(ACC=0.91)when all the attributes were used.Conclusion:Using sex,diet,infection status,initial BW,and area under the curve(AUC)at week 6,we could classify the final phenotypes/outcomes at the end stage of the experiment(at 12 weeks). 展开更多
关键词 collaborative cross genetic covariance HERITABILITY high-fat diet machine learning mouse model OBESITY type 2 diabetes
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滑动多层磁共振成像在直肠间质瘤分期中的应用价值 被引量:4
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作者 熊斌 Arnd-Oliver schaefer +2 位作者 Tobias Baumann 冯敢生 Mathias Langer 《华中科技大学学报(医学版)》 CAS CSCD 北大核心 2009年第2期224-227,共4页
目的探讨滑动多层(sliding multislice,SMS)磁共振成像(MRI)在胃肠道间质瘤(gastrointestinal stromal tumours,GIST)腹部分期中的应用价值和潜力。方法2005年9月至2008年1月8例由组织学和免疫组化检测证实的直肠GIST患者,均接受盆腔静... 目的探讨滑动多层(sliding multislice,SMS)磁共振成像(MRI)在胃肠道间质瘤(gastrointestinal stromal tumours,GIST)腹部分期中的应用价值和潜力。方法2005年9月至2008年1月8例由组织学和免疫组化检测证实的直肠GIST患者,均接受盆腔静止高分辨率MRI和腹部SMS MRI检查进行治疗前分期。在盆腔静止高分辨率MRI采用T2-TSE序列检查后,利用SMS技术的T1加权增强FLASH-2D序列在1 min内检查整个腹部。分析图像,分别了解直肠GIST原发部位情况及腹部远处转移情况。结果盆腔静止高分辨率MRI检查成功确定所有患者直肠GIST的大小、范围及局部侵犯程度,肿瘤最大直径介于1.7~11.0 cm。SMS MRI检查的图像质量能够满足对可能的肝转移灶、转移淋巴结、肠系膜转移灶和骨转移灶的评价。结论腹部SMS MRI联合盆腔静止高分辨率MRI可以在一次检查中完成直肠GIST的腹部分期。 展开更多
关键词 磁共振成像 胃肠道间质瘤 肿瘤分期
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世界各国铁路列车阻力和机车粘着系数公式的比较 被引量:5
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作者 H. H. schaefer 韩才元 《国外内燃机车》 1989年第2期35-43,共9页
列车阻力公式是编制列车运行时刻表、设计机车和分析能源消耗的主要根据。它还影响到电气化铁路的接触架空导线和供电设备的配置。本文对西德联邦铁路、法国国家铁路、美国铁路公司、巴西联邦铁路和印度国家铁路所应用的列车阻力公式和... 列车阻力公式是编制列车运行时刻表、设计机车和分析能源消耗的主要根据。它还影响到电气化铁路的接触架空导线和供电设备的配置。本文对西德联邦铁路、法国国家铁路、美国铁路公司、巴西联邦铁路和印度国家铁路所应用的列车阻力公式和机车粘着系数公式进行了比较。对于平均值偏差的离散度,运行阻力随列车种类的不同在±5.30%和±10%之间,曲线阻力公式的离散度为±25%,而加速阻力的离散度仅为±2%。 展开更多
关键词 列车阻力 机车 粘着系数 公式
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Sequestration of CO_(2)by concrete and natural minerals-current status,future potential,and additional benefits 被引量:1
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作者 Douglas A.schaefer Heng Gui Jianchu Xu 《Circular Agricultural Systems》 2024年第1期67-75,共9页
Concrete structures are some of the largest constructions in human civilization.Their manufacture releases CO_(2)into atmosphere,which is partially readsorbed by standing structures,and further release occurs when the... Concrete structures are some of the largest constructions in human civilization.Their manufacture releases CO_(2)into atmosphere,which is partially readsorbed by standing structures,and further release occurs when they are demolished.Concrete is chemically similar to basaltic minerals,both adsorb CO_(2)where they are exposed on the earth's surface.Sequestration of CO_(2)is beneficial to reduce atmospheric concentrations,and thus limit future temperature increases.Therefore,multiple options are being examined for CO_(2)sequestration.For the first time,we compare the CO_(2)sequestration capacity of these two materials.We review previous work quantifying CO_(2)sequestration capacity of both materials and for the first time,compare their potential quantitative roles.Costs of that are compiled,to the extent they have been examined.Costly grinding of these materials to small particle sizes accelerates CO_(2)sequestration,and mycorrhizae in agricultural soils might reduce the associated costs.Both these materials can improve nutrient status in agricultural soils,and limit acidification from external nitrogen fertilization.Limitations are discussed in terms of land-use and material availability,and soil pH conditions.We call for further experiments with these materials that compare CO_(2)sequestration and other biogeochemical processes in agricultural systems across climates,carried out especially where such materials are conveniently available. 展开更多
关键词 POTENTIAL RELEASE LIMIT
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Analysis of the human Atox 1 homologue in Wilson patients 被引量:4
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作者 Isabel Simon Mark schaefer +1 位作者 Jürgen Reichert Wolfgang Stremmel 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第15期2383-2387,共5页
AIM: To analyze the metallochaperone antioxidant-1 (Atox1) gene sequence in Wilson disease patients. METHODS: Mutation analysis of the four exons of the Atox1 gene including the intron- exon boundaries was performed i... AIM: To analyze the metallochaperone antioxidant-1 (Atox1) gene sequence in Wilson disease patients. METHODS: Mutation analysis of the four exons of the Atox1 gene including the intron- exon boundaries was performed in 63 Wilson disease patients by direct sequencing. RESULTS: From 63 selected patients no mutations were identified after the entire coding region including the intron- exon boundaries of Atox1 were sequenced. One known polymorphism within the Atox1 gene (5’UTR -99 T>C) in 31 (49%) of the Wilson patients as well as one previously undescribed variation (5’UTR -68 C>T) in 2 of the Wilson patients could be detected. Statistical analyses revealed that the existence of a variation within the Atox1- gene showed a tendency towards an earlier onset of the disease. CONCLUSION: Based on the data of this study, no major role can be attributed to Atox1 in the pathophysiology or clinical variation of Wilson disease. 展开更多
关键词 Antioxidant-1 Wilson disease Wilson's disease protein Mutation analysis
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Biliary phosphatidylcholine and lysophosphatidylcholine profiles in sclerosing cholangitis 被引量:3
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作者 Annika Gauss Robert Ehehalt +8 位作者 Wolf-Dieter Lehmann Gerhard Erben Karl-Heinz Weiss Yvonne schaefer Petra Kloeters-Plachky Adolf Stiehl Wolfgang Stremmel Peter Sauer Daniel Nils Gotthardt 《World Journal of Gastroenterology》 SCIE CAS 2013年第33期5454-5463,共10页
AIM:To analyze phospholipid profiles in intrahepatic bile from patients with primary sclerosing cholangitis(PSC)and secondary sclerosing cholangitis(SSC).METHODS:Intrahepatic bile specimens collected via endoscopic re... AIM:To analyze phospholipid profiles in intrahepatic bile from patients with primary sclerosing cholangitis(PSC)and secondary sclerosing cholangitis(SSC).METHODS:Intrahepatic bile specimens collected via endoscopic retrograde cholangiography from 41 patients were analyzed.Fourteen of these patients were diagnosed with PSC,10 with SSC,11 with choledocholithiasis or no identifiable biliary disease,and 6 with cholangiocellular carcinoma(CCC).Bile acid,cholesterol,protein,and bilirubin contents as well as pancreas lipase activity in bile were determined by biochemical methods.Phosphatidylcholine(PC)and lysophosphatidylcholine(LPC)species were quantified using nanoelectrospray ionization tandem mass spectrometry.RESULTS:Bile from all the examined patient groups showed a remarkably similar PC and LPC species composition,with only minor statistical differences.Total biliary PC concentrations were highest in controls(8030±1843 mol/L)and lowest in patients with CCC(1969±981 mol/L)(P=0.005,controls vs SSC and CCC,respectively,P<0.05).LPC contents in bile were overall low(4.2%±1.8%).Biliary LPC/PC ratios and ratios of biliary PC to bilirubin,PC to cholesterol,PC to protein,and PC to bile acids showed no intergroup differences.CONCLUSION:PC and LPC profiles being similar in patients with or without sclerosing cholangitis,these phospholipids are likely not of major pathogenetic importance in this disease group. 展开更多
关键词 Primary SCLEROSING CHOLANGITIS Secondary SCLEROSING CHOLANGITIS Cholangiocellular carcinoma PHOSPHATIDYLCHOLINE LYSOPHOSPHATIDYLCHOLINE BILE Mass spectrometry
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The influence of soil on vegetation structure and plant diversity in different tropical savannic and forest habitats 被引量:3
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作者 Priscyla Maria Silva Rodrigues Carlos Ernesto Gonçalves Reynaud schaefer +3 位作者 Jhonathan de Oliveira Silva Walnir Gomes Ferreira Júnior Rubens Manoel dos Santos Andreza Viana Neri 《Journal of Plant Ecology》 SCIE CSCD 2018年第2期226-236,共11页
Aims Soil plays an important role in the formation and heterogene-ity of habitats and thus can cause changes in vegetation struc-ture and plant diversity.The differentiation between Cerrado/savanna and forest is well ... Aims Soil plays an important role in the formation and heterogene-ity of habitats and thus can cause changes in vegetation struc-ture and plant diversity.The differentiation between Cerrado/savanna and forest is well known,but the relationship between soil and habitats from savannic or forest formations still needs to be better understood,particularly in tropical ecotonal areas.We studied the association between attributes of plant com-munities,namely structure and diversity,and physicochemical characteristics of soils in the Caatinga domain at the transition to Cerrado in Brazil.Methods Chemical and physical analyses of soils were performed in samples of 38 plots from savannic formations and 30 plots from forest forma-tions.Vegetation was characterized floristically and structurally in all plots,five habitats being assessed in each plant formation.Soil features and vegetation parameters were highly distinct among the different habitats.Important Findingsin general,forest habitats were more nutrient rich than savannic formation.Furthermore,soil variables showed effects both on vegetation structure and on its species diversity,more pronouncedly in the savannic formations.Habitats were structurally distinct,and diversity differed between savannic and forest communities;however,a higher differentiation occurred when the savannic formation habitats were compared among them.Although plant diversity did not differ among forest formation habitats,soil attributes showed a close relationship with edaphic factors and can contribute for similar vegetation.The soil-vegetation relationship in highly diverse ecotonal landscapes is important from the conservation biology point of view and aid in the execution of proactive plans for the maintenance of biodiversity.Thus,we noticed that diversity and soil behaves distinctly between savannic and forest communities. 展开更多
关键词 CERRADO dry forest edaphic variation vegetation-soil relationship ECOTONE
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Development and validation of an artificial intelligence model for predicting post-transplant hepatocellular cancer recurrence 被引量:2
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作者 Quirino Lai Carmine De Stefano +18 位作者 Jean Emond Prashant Bhangui Toru Ikegami Benedikt schaefer Maria Hoppe-Lotichius Anna Mrzljak Takashi Ito Marco Vivarelli Giuseppe Tisone Salvatore Agnes Giuseppe Maria Ettorre Massimo Rossi Emmanuel Tsochatzis Chung Mau Lo Chao-Long Chen Umberto Cillo Matteo Ravaioli Jan Paul Lerut the EurHeCaLT and the West-East LT Study Group 《Cancer Communications》 SCIE 2023年第12期1381-1385,共5页
Dear Editor,In recent years,criteria based on the combinationof morphology and biology have been proposed forimproving the selection of hepatocellular cancer(HCC)patients waiting for liver transplantation(LT)[1,2].Sin... Dear Editor,In recent years,criteria based on the combinationof morphology and biology have been proposed forimproving the selection of hepatocellular cancer(HCC)patients waiting for liver transplantation(LT)[1,2].Since all the proposed models showed suboptimalresults in predicting the risk of postLT recurrence,aprediction model constructed using artificial intelligence(Al)could be an attractive way to surpass this limit[3,4].Therefore,the Time_Radiological-response_Alpha-fetoproteIN_Artificial-Intelligence(TRAIN-AI)modelwas developed,combining morphology and biology tumorvariables. 展开更多
关键词 HEPATOCELLULAR CANCER artificial
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Land-sea breeze circulation structure on the west coast of the Yellow Sea,China
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作者 Yongxiang Ma Jinyuan Xin +8 位作者 Xiaoling Zhang Lindong Dai Klaus schaefer Shigong Wang Yuesi Wang Zifa Wang Fangkun Wu Xinrui Wu Guangzhou Fan 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第1期14-21,共8页
Land-sea breeze(LSB)is an atmospheric mesoscale circulation that occurs in the vicinity of the coast and is caused by uneven heating resulting from the difference in specific heat capacity between the sea and land sur... Land-sea breeze(LSB)is an atmospheric mesoscale circulation that occurs in the vicinity of the coast and is caused by uneven heating resulting from the difference in specific heat capacity between the sea and land surfaces.The circulation structure of LSB was quantitatively investigated with a Doppler wind lidar Windcube100s on the west coast of the Yellow Sea for the first time.The time of observation was 31 August to 28 September 2018.It was found that the height of LSB development was 700 m to 1300 m.The duration of conversion of LSB was between 6 h and 8 h.The biggest average horizontal sea-breeze wind speed at 425 m was 5.6 m s^(-1),and at 375 m it was 4.5 m s^(-1).During the conversion process from sea breeze to land breeze,the maximum wind shear exponent was 2.84 at 1300 m altitude.During the conversion process from land breeze to sea breeze,the maximum wind shear exponent was 1.28 at 700 m altitude.The differences in wind shear exponents between sea-breeze and landbreeze systems were between 0.2 and 3.6 at the same altitude.The maximum value of the wind shear exponent can reflect the height of LSB development. 展开更多
关键词 Land-sea breeze Vertical wind speed CCirculation structure Doppler wind lidar Yellow sea
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