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    题名 作者 年代 出处 被引量
1氨氧化古菌的生态学研究进展显示文摘上百年来细菌一直被认为是地球氨氧化过程的主要驱动者,2005年海洋中分离到迄今唯一的非极端环境泉古菌,发现其氧化氨态氮获得能源生长,是氨氧化古菌。氨氧化古菌和细菌对地球氨氧化过程的相对贡献率,是目前全球氮循环研究最重要的微生物生态学问题之一。已有的证据表明古菌在海洋氨氧化过程中发挥了重要作用,细菌则是土壤氨氧化过程的主要驱动者。本文重点探讨了原位自然环境下氨氧化古菌的生态学研究进展。贾仲君 翁佳华 林先贵 Ralf Conrad 2010微生物学报2010,50,4:40
2水稻土中铁氧化物的厌氧还原及其对微生物过程的影响显示文摘采用厌氧泥浆恒温培养实验 ,测定了添加 6种外源氧化铁后土壤中Fe(Ⅱ )和Fe(Ⅲ )浓度的变化 ,探讨了不同氧化铁的还原能力及其对土壤产H2 、产CO2 、产乙酸和产CH4 过程的影响。结果表明 :无定形氧化铁和纤铁矿易于被还原 ,两者的最终还原程度大体相同 ,但无定形氧化铁存在还原滞后现象 ;针铁矿、赤铁矿、Al取代针铁矿和Al取代赤铁矿难以被还原 ,表现出与对照相同的还原特征 ;铁还原能导致土壤中H2 和乙酸稳态浓度的降低 ,有效抑制了甲烷产生 ;添加Fe(OH) 3和纤铁矿后 ,Fe(Ⅲ )还原占总电子传递的贡献率由对照的 1 8.3 0 %增至 63 .3 2 %和 46.90 % ,而形成甲烷的电子传递贡献率由对照的 80 .92 %降至 3 5 .85 %和 5 2 .3 2 % ,Fe(Ⅲ )还原对电子的竞争消耗 。曲东 张一平 Schnell S Conrad R 2003土壤学报2003,40,6:40
3Identification of squamous cell carcinoma associated proteins by proteomics and loss of beta tropomyosin expression in esophageal cancer显示文摘AIM: To assess the proteome of normal versus tumor tissue in squamous cell carcinoma of the esophagus (SCCE) in Iranian patients and compare our results with former reports by using proteomics. METHODS: Protein was extracted from normal and tumor tissues. Two dimensional electrophoresis was carried out and spots with differential expression were identified with mass spectrometry. RNA extraction and RT-PCR along with immunodetection were performed. RESULTS: Fourteen proteins were found whose expression levels differed in tumor compared to normal tissues. Mass spectrometric analysis resulted in the identification of β-tropomyosin (TMβ), myosin light chain 2 (and its isoform), myosin regulatory light chain 2, peroxyredoxin 2, annexinⅠand an unknown polypeptide as the down regulated polypeptides in tumor tissue. Heat shock protein 70 (HSP70), TPM4-ALK fusion oncoprotein 2, myosin light polypeptide 6, keratinⅠ, GH16431p and calreticulin were the up-regulated polypeptides found in tumor tissue. Several of these proteins, such as TMβ,HSP70, annexinⅠ, calreticulin, TPM4-ALK and isoforms of myosins, have been well recognized in tumorigenesis of esophageal or other types of cancers. CONCLUSION: Our study not only supports the involve- ment of some of the formerly reported proteins in SCCE but also introduces additional proteins found to be lost in SCCE, including TMβ.Ferdous Rastgar Jazii Zahra Najafi Reza Malekzadeh Thomas P Conrads Abed Ali Ziaee Christian Abnet Mansour Yazdznbod Ali Asghar Karkhane Ghasem H Salekdeh 2006World Journal of Gastroenterology2006,12,44:14
4汉字部件及其位置的发展研究显示文摘选取小学二年级、五年级学生和大学生对汉字部件及其位置的发展进行了研究。结果表明,汉字部件的发展在3个年级表现出一致的趋势。部件位置的发展趋势不一致,它在小学五年级阶段表现出更重要的作用。彭聃龄 郭瑞芳 Conrad Perry 2006心理与行为研究2006,4,1:11
5Broken hearts:Iron overload,ferroptosis and cardiomyopathy显示文摘In a recently published paper in Proc Natl Acad Sci USA,Fang et al.elegantly demonstrated that doxorubicin treatment or transient ischemia/reperfusion in mice triggers ferroptosis,a distinctive form of necrotic cell death marked by iron-dependent lipid peroxidation,which is the main underlying mechanism in the pathogenesis of cardiomyopathy.Marcus Conrad Bettina Proneth 2019Cell Research2019,29,4:11
6Differential treatment and early outcome in the interventional endoscopic management of pancreatic pseudocysts in 27 patients显示文摘瞄准:胰腺的假包囊(PPC ) 仅仅在腹的疼痛的情况中作为胰腺炎的复杂并发症被接近,感染,流血,并且压缩到胃肠道或胆汁的树上。方法:从 02/01/2002 到 05/31/2004,经历了 interventional 的有征兆的 PPC 的所有连续病人内视镜的途径在这飞行员盒子系列研究被评估:组(Gr ) 我主要经皮(外部) ,指导超声的排水。Gr。II 主要的指导 EUS 的胰囊肿胃吻合术。Gr。包括 intracystic necrosectomy 的 III-EUS-guided 胰囊肿胃吻合术。结果:( = “列在后面在上面”:n = 27 ) :Gr。我(n = 9;33.3%) :没有抱怨(n = 3 ) ;变化一进内部排水外部(n = 4 ) ;复杂并发症:(a) 流血(n = 1 ) 在 ICU 由 3 d 列在后面,在 40 d 以后的分泌物;(b) 腐败吃惊(n = 1 ) 由 ICU 和几剖腹术列在后面规划洗室年龄和 necrosectomy,在 74 d 以后的死亡。Gr。II (n = 13;48.1%) :没有抱怨(n = 11 ) ;外部排水(n = 2 ) ;从 13 个盒子的复杂并发症 / 问题:第二分开的假包囊(n = 1 ) 与外部排水(自从与主要内部排水的没有通讯) ;剩余包囊的感染(n = 1 )+ 追随者外部排水;自发的 PPC 穿孔(n = 1 ) 用片断并且随后的胰囊肿胃吻合术的开始的 + 追随者闭合为 2 d 的 ICU。Gr。III (n = 5;18.5%) :在所有病人的没有抱怨,在要求的一般水准二内视镜的过程(变化, 2-6 ) 。结论:胰腺的假包囊的 Interventional 内视镜的管理关于复杂并发症率(11.1%) 和死亡(3.7%) 是有与外科和可接受的结果相比的低侵略海角的一种合理其他的治疗选择,作为由这些证明起始的学习结果。Uwe Will Conrad Wegener Kai-Ivo Graf Igor Wanzar Thomas Manger Frank Meyer 2006World Journal of Gastroenterology2006,12,26:9
7New Jurassic Pseudopolycentropodids from China (Insecta: Mecoptera)显示文摘In this paper two new species of fossil Pseudopolycentropus Handlirsch, 1906 are described: Pseudopolycentropus janeannae sp. nov. and P. novokshonovi, sp. nov. All of them were recovered from the Middle Jurassic non-marine sedimentary strata of northeastern China. The new material from China reveals that the early diversification of pseudopolycentropodids was well underway by the Middle Jurassic.REN Dong SHIH Chungkun Conrad C. LABANDEIRA 2010Acta Geologica Sinica(English Edition)2010,84,1:9
8New Mesozoic Mesopsychidae (Mecoptera) from Northeastern China显示文摘中生代家庭 Mesopsychidae Tillyard, 1917 目前由七个描述的类和 13 种类组成从中间 -- 对澳大利亚,南非和欧亚大陆的早白垩纪三叠纪。在现在的纸,一个新类和石块 mesopsychids 的三新种被描述增加重要分布并且对家庭的 stratigraphic 扩展。这发现在中国记录石块 Mesopsychidae 的第一个正式记录。两张 Lichnomesopsyche gloriae 情报。et sp。nov。并且 L。daohugouensis 情报。et sp。nov。从内部蒙古的中间的侏罗记 Jiulongshan 形成被发现,而 Vitimopsyche kozlovi sp。中间的早白垩纪年龄, nov 从北 Hebei 省的 Jehol 生物区系被收集。从中国的这新、保存得很好的材料揭示完全、以前未知的身体特征,包括头,天线, mouthparts,腿和腹部。这些新 taxa 的精细、长的 proboscides 显示他们在外部地暴露的、充满营养素的液体上正在喂裸子植物排卵结果实,并且不能穿透表面外皮可归因主要到锥刺的缺席。这些 proboscides 发源,也许乘,在基础长翅目之中并且机能上地并且与石块忍受的相等的 mouthparts 会聚的在结构上并且现存双翅目,鳞翅目, Neuroptera 和翘目。REN Dong Conrad C. LABANDEIRA SHIH ChungKun 2010Acta Geologica Sinica(English Edition)2010,84,4:9
9Importance of hydrogenotrophic, aceticlastic and methylotrophic methanogenesis for methane production in terrestrial, aquatic and other anoxic environments: A mini review显示文摘Microbial methanogenesis is a major source of the greenhouse gas methane(CH4).It is the final step in the anaerobic degradation of organic matter when inorganic electron acceptors such as nitrate,ferric iron,or sulfate have been depleted.Knowledge of this degradation pathway is important for the creation of mechanistic models,prediction of future CH4 emission scenarios,and development of mitigation strategies.In most anoxic environments,CH4 is produced from either acetate(aceticlastic methanogenesis)or hydrogen(H2)plus carbon dioxide(CO2)(hydrogenotrophic methanogenesis).Hydrogen can be replaced by other CO2-type methanogenesis,using formate,carbon monoxide(CO),or alcohols as substrates.The ratio of these two pathways is tightly constrained by the stoichiometry of conversion processes.If the degradation of organic matter is complete(e.g.,degradation of straw in rice paddies),then fermentation eventually results in production of acetate and H2 at a ratio of>67%aceticlastic and<33%hydrogenotrophic methanogensis.However,acetate production can be favored when heterotrophic or chemolithotrophic acetogenesis is enhanced,and H2 production can be favored when syntrophic acetate oxidation is enhanced.This typically occurs at low and elevated temperatures,respectively.Thus,temperature can strongly influence the methanogenic pathway,which may range from 100%aceticlastic methanogenesis at low temperatures to 100%hydrogenotrophic methanogenesis at high temperatures.However,if the degradation of organic matter is not complete(e.g.,degradation of soil organic matter),the stoichiometry of fermentation is not tightly constrained,resulting,for example,in the preferential production of H2,followed by hydrogenotrophic methanogenesis.Preferential production of CH4 by either aceticlastic or hydrogenotrophic methanogenesis can also happen if one of the methanogenic substrates is not consumed by methanogens but is,instead,accumulated,volatilized,or utilized otherwise.Methylotrophic methanogens,which can use methanol as a substrate,are widespread,but it is unlikely that methanol is produced in similar quantities as acetate,CO2,and H2.Methylotrophic methanogenesis is important in saline environments,where compatible solutes are degraded to methyl compounds(trimethyl amine and dimethyl sulfide)and then serve as non-competitive substrates,while acetate and hydrogen are degraded by non-methanogenic processes,e.g.,sulfate reduction.Ralf CONRAD 2020Pedosphere2020,30,1:8
10Machine-learned multi-system surrogate models for materials prediction显示文摘Surrogate machine-learning models are transforming computational materials science by predicting properties of materials with the accuracy of ab initio methods at a fraction of the computational cost.We demonstrate surrogate models that simultaneously interpolate energies of different materials on a dataset of 10 binary alloys(AgCu,AlFe,AlMg,AlNi,AlTi,CoNi,CuFe,CuNi,FeV,and NbNi)with 10 different species and all possible fcc,bcc,and hcp structures up to eight atoms in the unit cell,15,950 structures in total.We find that the deviation of prediction errors when increasing the number of simultaneously modeled alloys is<1 meV/atom.Several state-of-the-art materials representations and learning algorithms were found to qualitatively agree on the prediction errors of formation enthalpy with relative errors of<2.5% for all systems.Chandramouli Nyshadham Matthias Rupp Brayden Bekker Alexander V.Shapeev Tim Mueller Conrad W.Rosenbrock Gábor Csányi David W.Wingate Gus L.W.Hart 2019npj Computational Materials2019,,1:8
11饱和黏土高压压缩特性的微观机制——研究现状与思路显示文摘通过归纳分析发现,适用于描述常压条件下黏土压缩特性的扩散双电层理论和不平行板模型均不能对高压条件饱和黏土的双线性压缩特性进行解释。将黏土的孔隙划分为团聚体间、颗粒间及颗粒板内三层面可很好地对饱和黏土的高压压缩过程进行定性描述:高压条件下,除团聚体间及板间扩散双电层两部分的自由水分子的排出外,晶层间规则排列的结合水分子也将被逐层挤出。而该小间距条件下,基于扩散双电层机制的理论解释已不再适用,且由于水分子与晶层间的特殊结合,其他Non-DLVO作用力的出现亦必须重新加以考虑。基于此,提出了从理论上利用格子密度泛函理论描述黏土矿物界面外水分子的特殊结合形态,并嵌入该格子模型于分子动力模型中,从分子尺度研究高压条件下水-界面间的相互作用,从而最终建立基于分子层面黏土高压压缩本构关系的新思路。况联飞 周国庆 Conrad Boley 邹亚洲 商翔宇 2013煤炭学报2013,38,2:7
12Role of human papillomavirus in oropharyngeal squamous cell carcinoma: A review显示文摘Human papillomavirus(HPV) has been implicated in the pathogenesis of a subset of oropharyngeal squamous cell carcinoma. As a result, traditional paradigms in relation to the management of head and neck squamous cell carcinoma have been changing. Research into HPVrelated oropharyngeal squamous cell carcinoma is rapidly expanding, however many molecular pathological and clinical aspects of the role of HPV remain uncertain and are the subject of ongoing investigation. A detailed search of the literature pertaining to HPV-related oropharyngeal squamous cell carcinoma was performed and information on the topic was gathered. In this article, we present an extensive review of the current literature on the role of HPV in oropharyngeal squamous cell carcinoma, particularly in relation to epidemiology, risk factors, carcinogenesis, biomarkers and clinicalimplications. HPV has been established as a causative agent in oropharyngeal squamous cell carcinoma and biologically active HPV can act as a prognosticator with better overall survival than HPV-negative tumours. A distinct group of younger patients with limited tobacco and alcohol exposure have emerged as characteristic of this HPV-related subset of squamous cell carcinoma of the head and neck. However, the exact molecular mechanisms of carcinogenesis are not completely understood and further studies are needed to assist development of optimal prevention and treatment modalities.Robbie SR Woods Esther M O'Regan Susan Kennedy Cara Martin John J O'Leary Conrad Timon 2014World Journal of Clinical Cases2014,2,6:5
13Machine-learned interatomic potentials for alloys and alloy phase diagrams显示文摘We introduce machine-learned potentials for Ag-Pd to describe the energy of alloy configurations over a wide range of compositions.We compare two different approaches.Moment tensor potentials(MTPs)are polynomial-like functions of interatomic distances and angles.The Gaussian approximation potential(GAP)framework uses kernel regression,and we use the smooth overlap of atomic position(SOAP)representation of atomic neighborhoods that consist of a complete set of rotational and permutational invariants provided by the power spectrum of the spherical Fourier transform of the neighbor density.Both types of potentials give excellent accuracy for a wide range of compositions,competitive with the accuracy of cluster expansion,a benchmark for this system.While both models are able to describe small deformations away from the lattice positions,SOAP-GAP excels at transferability as shown by sensible transformation paths between configurations,and MTP allows,due to its lower computational cost,the calculation of compositional phase diagrams.Given the fact that both methods perform nearly as well as cluster expansion but yield off-lattice models,we expect them to open new avenues in computational materials modeling for alloys.Conrad W.Rosenbrock Konstantin Gubaev Alexander VShapeev Livia B.Pártay Noam Bernstein Gábor Csányi Gus L.W.Hart 2021npj Computational Materials2021,,1:5
14间隙灌溉和控释肥施用对稻田土壤产甲烷微生物的影响显示文摘间隙灌溉和控释肥施用影响稻田CH_4的产生和排放,然而其微生物机理尚不清楚。本研究通过采集稻季田间原位试验新鲜土样,采用核酸定量技术(qPCR)和末端限制性片段长度多态性(T-RFLP)技术,研究间隙灌溉和控释肥施用对稻田土壤产甲烷微生物群落丰度和结构的影响。结果表明,稻季CH_4排放量与古菌、产甲烷菌(mcr A基因)和甲烷氧化菌(pmo A基因)数量均呈极显著正相关关系(P<0.01),而与细菌数量无显著相关性。间隙灌溉显著影响产甲烷菌和甲烷氧化菌数量的季节变化,其中烤田抑制产甲烷菌生长,而对甲烷氧化菌数量没有显著影响。与尿素相比,施用控释肥增加了稻田土壤细菌、古菌和产甲烷菌数量,降低了甲烷氧化菌数量。土壤古菌群落的优势T-RFs片段为184bp和391bp,其中184bp片段的相对丰度随着间隙灌溉的进行由45%~55%降低到23%~30%;而391bp片段则相反,其相对丰度由12%~18%增加到23%~26%。典型相关性分析(CCA)表明间隙灌溉显著影响土壤古菌群落结构(P<0.001),而控释肥施用对土壤古菌群落结构没有明显影响。纪洋 于海洋 CONRAD Ralf 徐华 2017土壤2017,49,6:5
15Taming of macrophage and microglial cell activation by microRNA-124显示文摘Ashley T Conrad Bonnie N Dittel 2011Cell Research2011,21,2:5
16Compressibility of fine-grained soils subjected to closed-system freezing and thaw consolidation显示文摘In order to investigate the effects of freezing and thawing on the compressibility of fine-grained soils, freezing and thawing tests and subsequent compression tests with fine-grained soils in an oedometer were carried out. During the freezing, a part of the soils is loosened and another part is over-consolidated under the freezing pressure σE. The compression curves after the freezing and thaw consolidation are neither different from the normal consolidation curve nor from the rebound curve of an unfrozen soil, until the consolidation pressure σz = σE is arrived. Based on the experimental results, a theoretical model has been devel- oped to predict the frost heaves, the thaw-settlements and the compressive deformations of fine-grained soils after the thaw consolidation. The theoretical results are very close to the experimental results.BOLEY Conrad 2009Mining Science and Technology2009,19,5:5
17外源氧化铁对水稻土中有机酸含量的影响显示文摘在水稻土泥浆中添加Fe(OH) 3 可显著降低乙酸浓度 .在新鲜水稻土样品中 ,由于添加Fe(OH) 3导致对乙酸的竞争消耗 ,在培养 5d后 ,乙酸浓度降至 10~ 2 0 μmol·L-1的稳态浓度 ,而此刻对照中的乙酸浓度仍在 12 0 0 μmol·L-1以上 .在乙酸产生量较低的土壤中 ,添加Fe(OH) 3 可完全消耗体系中的乙酸 ,并导致产CH4过程的完全被抑制 .添加纤铁矿同样可使乙酸浓度显著减少 ,但作用效果不如无定形氧化铁 .添加赤铁矿可造成培养初期 (10d以内 )乙酸的大量积累 ,但并不引起产CH4量的增大 .添加Fe(OH) 3 、纤铁矿及铝取代针铁矿 ,能引起厌氧培养的水稻土中丙酸浓度的降低 ,其抑制效率为Fe(OH) 3 >纤铁矿 >铝取代针铁矿 .新鲜土样和经过 11周厌氧处理后的土样中 ,有机酸种类和含量有较大差别 .曲东 Sylvia Schnell Rolf Conrad 2002应用生态学报2002,13,11:5
18间隙灌溉和控释肥施用耦合措施对稻麦轮作系统土壤微生物群落丰度的影响显示文摘间隙灌溉模式下控释肥施用可减缓稻麦轮作系统CH_4和N_2O排放交互排放效应,从而降低综合温室效应,然而有关间隙灌溉和控释肥施用耦合措施对稻麦轮作系统土壤微生物的影响鲜有研究。通过采集稻麦轮作系统田间原位试验新鲜土样,采用核酸定量技术研究间隙灌溉和控释肥施用耦合措施下稻麦轮作系统土壤微生物群落丰度的变化,以探讨此耦合措施降低稻麦轮作系统降低CH_4和N_2O排放的微生物机理。结果发现,除古菌外,稻季土壤细菌、产甲烷菌、甲烷氧化菌、氨氧化菌和反硝化菌群落丰度均高于麦季;间隙灌溉显著影响稻田产甲烷菌、甲烷氧化菌、氨氧化菌和反硝化菌数量的季节变化;与尿素相比,施用控释肥增加了稻麦轮作系统细菌、古菌和产甲烷菌数量,降低了甲烷氧化菌、氨氧化菌、反硝化菌数量。稻季CH_4和N_2O的排放量与土壤微生物丰度之间存在显著相关性:CH_4排放量与古菌、产甲烷菌和甲烷氧化菌数量均呈极显著正相关关系(P<0.01),而与氨氧化菌数量呈显著负相关关系(P<0.05);N_2O排放量与氨氧化菌、甲烷氧化菌、nirK型和nosZ型反硝化菌数量均呈显著正相关关系(P<0.05),而与nir S型反硝化菌无显著相关性。研究表明,间隙灌溉和控释肥施用耦合措施通过影响稻麦轮作系统相关功能微生物的群落丰度进而减缓CH_4和N_2O气体的交互排放效应。纪洋 于海洋 Ralf Conrad 徐华 2017生态环境学报2017,26,10:5
19Safety, Tolerability, and Clinical Response After Fecal Transplantation in Children and Young Adults With Ulcerative Colitis显示文摘Sachin Kunde Angela Pham Sarah Bonczyk Teri Crumb Meg Duba Harold Conrad Deborah Cloney Subra Kugathasan 2013Journal of Pediatric Gastroenterology and Nutrition2013,,6:4
20Soil biodiversity in a rapidly changing world显示文摘Microbes are simple single-cell organisms,but have an enormous practical significance for human kind.Soil microbes make our planet habitable,and the planet's rapidly changing environments in turn have a profound impact on the soil microbial communities,both positively and negatively.It is thus crucial to better understand how abiotic and biotic factors interact to assemble microbiomes under the given environmental conditions,and how they modulate the intrinsic link between microbial diversity and ecosystem function.From a functional viewpoint.Zhongjun JIA David D.MYROLD Ralf CONRAD 2020Pedosphere2020,30,1:4
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