检索结果-南通市图书馆

Finite-Size Conformational Transitions: A Unifying Concept Underlying Chromosome Dynamics

Communications in Theoretical Physics 2014年第10期61卷 607-616页

作者： Bertrand R.Caré Pascal Carrivain Thierry Forné jean-marc Victor Annick Lesne Laboratoire de Physique Théorique de la Matière Condensée CNRS UMR 7600UPMC University Paris 06F-75005ParisFrance CNRS GDR 3536 UPMC University Paris 06F-75005ParisFrance Institut de Génétique Humaine CNRS UPR 1142 MontpellierFrance Institut de Génétique Moléculaire de Montpellier CNRS UMR 5535University of MontpellierMontpellierFrance Kavli Institute for Theoretical Physics China CAS

Investigating average thermodynamic quantities is not sufficient to understand conformational transitions of a finite-size polymer. We propose that such transitions are better described in terms of the probability distribution of some finite-size order parameter, and the evolution of this distribution as a control parameter varies. We demonstrate this claim for the coil-globule transition of a linear polymer and its mapping onto a two-state model. In a biological context, polymer models delineate the physical constraints experienced by the genome at different levels of organization,from DNA to chromatin to chromosome. We apply our finite-size approach to the formation of plectonemes in a DNA segment submitted to an applied torque and the ensuing helix-coil transition that can be numerically observed, with a coexistence of the helix and coil states in a range of parameters. Polymer models are also essential to analyze recent in vivo experiments providing the frequency of pairwise contacts between genomic loci. The probability distribution of these contacts yields quantitative information on the conformational fluctuations of chromosome regions. The changes observed in the shape of the distribution when the cell type or the physiological conditions vary may reveal an epigenetic modulation of the conformational constraints experienced by the chromosomes.

关键词： coil-globule transition helix-coil transition chromosome conformational capture two-state model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Impact of homogeneous pathologic response to preoperative chemotherapy in patients with multiple colorectal liver metastases

引用

World Journal of Gastroenterology 2017年第45期23卷 8027-8034页

作者： Charles Sabbagh Denis Chatelain Christophe Attencourt jean-Paul Joly Bruno Chauffert Cyril Cosse jean-marc Regimbeau Depart-ment of Digestive and Oncologic Surgery Amiens University Medical Center INSERM U1088 Jules Verne University of Picardie University of Picardie Department of Anatomic Pathology Amiens University Medical Center Department of Hepatogastroenterology Amiens University Medical Center Department of Medical Oncology Amiens University Medical Center EA4294 Jules Verne University of Picardie

AIM To analyze the homogeneity of pathologic response to preoperative chemotherapy(PRPC) after chemotherapy in patients with multiple liver metastases(LM).METHODS From September 2011 to August 2014,patients with at least two LM undergoing preoperative chemotherapy prior to resection were included in this retrospective,single-center study. The endpoints were PRPC homogeneity(according to both the Rubbia-Brandt and MD Anderson classifications),the impact of PRPC on the MDT decision,factors associated with homogeneous PRPC and overall survival of patients with vs. without homogeneous *** seventy-three patients with a total of 88 liver resections(including 15 two-stage procedures) were included in the study. The homogeneous PRPC rate was 55% according to the Rubbia-Brandt classification and 53% according to the MD Anderson classification. The MDT decision was modified by the PRPC in only 2.7% of patients(n = 2). CONCLUSION The PRPC was homogeneous in only one half of patients and had very little influence on the MDT decision.

关键词： Liver metastases Pathological response Homogeneity Preoperative chemotherapy Colorectal cancer

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Procalcitonin and intestinal ischemia:A review of the literature

引用

World Journal of Gastroenterology 2014年第47期20卷 17773-17778页

作者： Cyril Cosse Charles Sabbagh Sad Kamel Antoine Galmiche jean-marc Regimbeau INSERM U1088 Jules Verne University of Picardie80054 AmiensFrance Department of Digestive and Oncological Surgery Amiens University HospitalJules Verne University of PicardiePlace Victor PauchetF-80054 Amiens cedex 01France Clinical Research Center Amiens University Hospital80054 Amiens Cedex 01France Department of Biochemistry Amiens University HospitalJules Verne University of PicardieF-80054 AmiensFrance EA4294 Jules Verne University of PicardieF-80054 AmiensFrance

Intestinal ischemia is common after emergency gastrointestinal or cardiovascular *** present,there are no diagnostic tools for the early diagnosis of intestinal *** the last decade,procalcitonin(PCT)has been suggested as a marker of this ***,we review the use of PCT as a diagnostic tool for intestinal *** reviewers independently searched the Pub Med and EMBASE databases for articles on intestinal ischemia and *** then considered(1)the criteria applicable to preclinical and clinicaldata;and(2)PCT’s predictive value in the diagnosis of intestinal *** quality was rated according to the STAndards for Reporting of Diagnostic *** 1993 and 2014,seven studies(including two preclinical studies and five clinical studies)dealt with the use of PCT to diagnose intestinal ***’s sensitivity,specificity,positive predictive value and negative predictive value ranged between 72%and 100%;68%and 91%;27%and 90%and 81%and 100%,*** area under the receiver operating characteristic curve ranged from 0.77 to *** view of the preclinical and clinical data,we consider that PCT can be used in daily practice as a tool for diagnosing intestinal ischemia.

关键词： Procalcitonin Intestinal Ischemia Diagnosis Review

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Performance Evaluation of MWCNTs Reinforced Cement Mortar Composites using Natural and Commercial Surfactants

引用

Journal of Wuhan University of Technology(Materials Science) 2022年第1期37卷 47-57页

作者： Qareeb Ullah Rao Arsalan Khushnood Sajjad Ahmad Muhammad Usman Shad Muhammad jean-marc Tulliani School of Civil and Environmental Engineering National University of Sciences and TechnologyIslamabad-44000Pakistan Department of Structural Geotechnical and Building EngineeringPolitecnico di TorinoTurin-10129Italy Department of Civil Engineering FE&TBahauddin Zakariya UniversityMultan-56000Pakistan Department of Applied Science and Technology Politecnico di TorinoTurin-10129Italy

An efficient and promising approach for effectively dispersing multi-walled carbon nanotubes(MWCNTs)in cementitious composites has been *** naturally occurring organic extracts from species of indigenously known‘Keekar’trees scattered along tropical and sub-tropical regions;is found as an exceptional replacement to the non-natural commercial *** the initial phase of investigation,ideal surfactant’s content required for efficient dispersion of MWCNTs in solution was determined using ultra-violet *** experimental investigations were then extended to five different cement composite formulations containing 0.0,0.025,0.05,0.08 and 0.10%MWCNTs by weight of *** was observed that the natural surfactant produced efficient dispersion at much reduced cost(approx.14%)compared with the commercial *** estimated weight efficiency factor f was found 6.5 times higher for the proposed sustainable replacement to the conventional along with remarkable increase of 23%in modulus of rupture on 0.08 wt%addition of *** strength enhancement,the dispersed MWCNTs also improved the first crack and ultimate fracture toughness by 51.5%and 35.9%,*** field emission scanning electron microscopy of the cryofractured samples revealed efficient dispersion of MWCNTs in the matrix leading to the phenomenon of effective crack bridging and crack branching in the composite ***,the proposed scheme significantly reduced the early age volumetric shrinkage by 39%.

关键词： MWCNTs acacia nilotica gum keekar triton X-100 fracture crack bridging cement mortar early age micro-cracking sustainability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

锆基非晶合金的动态弛豫机制和高温流变行为

引用

力学学报 2020年第2期52卷 360-368页

作者：郝奇乔吉超 jean-marc Pelletier 西北工业大学力学与土木建筑学院西安710072 INSA-Lyon MATEIS UMR5510F-69621 VilleurbanneFrance

非晶合金的动态弛豫机制对于理解其塑性变形,玻璃转变行为,扩散机制以及晶化行为都至关重要.非晶合金的力学性能与动态弛豫机制的本征关联是该领域当前重要科学问题之一.本文借助于动态力学分析(DMA),探索了Zr50Cu40Al10块体非晶合金从... 详细信息

非晶合金的动态弛豫机制对于理解其塑性变形,玻璃转变行为,扩散机制以及晶化行为都至关重要.非晶合金的力学性能与动态弛豫机制的本征关联是该领域当前重要科学问题之一.本文借助于动态力学分析(DMA),探索了Zr50Cu40Al10块体非晶合金从室温到过冷液相区宽温度范围内的动态力学行为.通过单轴拉伸实验,研究了玻璃转变温度附近的高温流变行为.基于准点缺陷理论(quasi-point defects theory),对两种力学行为的适用性以及宏观力学行为变化过程中微观结构的演化规律进行描述.研究结果表明,准点缺陷理论可以很好地描述非晶合金损耗模量α弛豫的主曲线.基于非晶合金的内耗行为,玻璃转变温度以下原子运动的激活能Uβ为0.63 eV.与准点缺陷浓度对应的关联因子χ在玻璃转变温度以下约为0.38,而在玻璃转变温度以上则线性增大.Zr50Cu40Al10块体非晶合金在玻璃转变温度附近,随温度和应变速率的不同而在拉伸实验中显示出均匀的或不均匀的流变行为.非晶合金的高温流变行为不仅可以通过扩展指数函数和自由体积理论来描述,还可以通过基于微剪切畴(shear micro-domains,SMDs)的准点缺陷理论来描述.

关键词：非晶合金动态力学分析高温拉伸结构弛豫准点缺陷理论

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Very high conservation between Cyp6a2 from Drosophila melanogaster and its ortholog Cyp6a26 from D. simulans

引用

Insect Science 2007年第1期14卷 15-27页

作者： SOPHIE TARES LAURY ARTHAUD ALEXANDRA BRUN-BARALE DIDIER CROCHARD jean-marc BRIDE marcEL AMICHOT Institut National de la Recherche Agronomique UMR ROSE 1112 Sophia-Antipolis France

Although Drosophila simulans is closely related to D. melanogaster, very few cytochrome P450 genes have been studied in this species until now. As Cyp6a2 from D. melanogaster is a major gene implicated in the detoxification of xenobiotic molecules, we decided to look for its ortholog in D. simulans. The isolated gene, Cyp6a26, presents structural characteristics very similar to those of Cyp6a2： an identical size of 1590-bp comprising two exons separated by a 69-bp intron and a nucleotide sequence homology of 95%. Many putative transcriptionally important motifs were identified in the upstream DNAs of the two genes but only 16 elements are in common positions. Treatment of flies with phenobarbital leads to an increased production of Cyp6a26 mRNAs. The expression of Cyp6a26 mRNAs varies following developmental stages in the same manner as Cyp6a2. Immunohistochemistry experiments of phenobarbital-treated adult drosophila show that the spatial expression pattern of the two proteins is also conserved between the two species. All these data argue in favor of the conservation of the function of these homologous genes between the two Drosophila species.

关键词： cytochrome P450 Drosophila ortholog mRNA expression promotor

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Holography in the invisible. From the thermal infrared to the terahertz waves: outstanding applications and fundamental limits

引用

Light(Advanced Manufacturing) 2022年第2期3卷 157-170页

作者： marc Georges Yuchen Zhao jean-François Vandenrijt Centre Spatial de Liège STAR Research InstituteLiège UniversitéLiege Science Park4031 Angleur(Liège)Belgium

Since its invention,holography has been mostly applied at visible wavelengths in a variety of ***,non-destructive testing of manufactured objects was a driver for developing holographic methods and all related ones based on the speckle pattern *** substantial limitation of holographic non-destructive testing is the setup stability requirements directly related to the laser *** observation has driven some works for 15 years:developing holography at wavelengths much longer than visible *** this paper,we will first review researches carried out in the infrared,mostly digital holography at thermal infrared wavelengths around 10 *** will discuss the advantages of using such wavelengths and show different examples of *** nondestructive testing,large wavelengths allow using digital holography in perturbed environments on large objects and measure large deformations,typical of the aerospace *** astonishing applications such as reconstructing scenes through smoke and flames were *** moving further in the spectrum,digital holography with so-called Terahertz waves(up to 3 millimeters wavelength)has also been *** main advantage here is that these waves easily penetrate some ***,one can envisage Terahertz digital holography to reconstruct the amplitude and phase of visually opaque *** review some cases in which Terahertz digital holography has shown potential in biomedical and industrial *** will also address some fundamental bottlenecks that prevent fully benefiting from the advantages of digital holography when increasing the wavelength.

关键词： Long wave infrared Terahertz waves Digital holography Speckle interferometry

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frey procedure for the treatment of chronic pancreatitis associated with common bile duct stricture

引用

Hepatobiliary & Pancreatic Diseases International 2013年第6期12卷 637-644页

作者： Lionel Rebibo Thierry Yzet Cyril Cosse Richard Delcenserie Eric Bartoli jean-marc Regimbeau Department of Digestive Surgery Amiens University Medical Center the Jules Verne University of Picardie Department of Radiology Amiens University Medical Center and the Jules Verne University of Picardie Department of Digestive SurgeryAmiens University Medical Center and the Jules Verne University of Picardie Department of Gastroenterology Amiens University Medical Center and the Jules Verne University of Picardie

BACKGROUND:The Frey procedure(FP)is the treatment of choice for symptomatic chronic pancreatitis(CP).In cases of biliary stricture,biliary derivation can be performed by choledochoduodenostomy,Roux-en-Y choledochojejunostomy or,more recently,reinsertion of the common bile duct(CBD)into the resection *** objective of the present study was to evaluate the outcomes associated with each of these three types of biliary ***:We retrospectively analyzed demographic,CPrelated,surgical and follow-up data for patients having undergone FP for CP with biliary derivation between 2004and 2012 in our university medical *** primary efficacy endpoint was the rate of CBD stricture *** secondary endpoints were surgical parameters,postoperative complications,postoperative follow-up and the presence of risk factors for secondary CBD ***:Eighty patients underwent surgery for CP during the study *** these,15 patients received biliary derivation with the *** of the FPs(53.3%)were combined with choledochoduodenostomy,4(26.7%)with choledochojejunostomy and 3(20.0%)with reinsertion of the CBD into the resection *** mean operating time was *** complications(73.3%)were recorded,including one major complication(6.7%)that necessitated radiologicallyguided drainage of an abdominal *** mean(range)length of stay was 17 days(8-28)and the median(range)follow-up time was 35.2 months(7.2-95.4).Two patients presented stricture after CBD reinsertion into the resection cavity;one was treated with radiologically-guided dilatation and the other underwent revisional Roux-en-Y *** patients presented alkaline reflux gastritis(37.5%),one(12.5%)cholangitis and one CBD stricture after FP with *** risk factors for secondary CBD stricture were ***:As part of a biliary derivation,the FP gave good *** did not observe any complications specifically relat

关键词： common bile duct stricture chronic pancreatitis Frey procedure pancreatectomy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental and Statistical Analysis of Fatigue Behavior in Zr-based Bulk Metallic Glass

引用

稀有金属材料与工程 2024年第11期53卷 3010-3016页

作者： Yao Zhifeng Qiao Jichao Pelletier jean-marc Yao Yao School of Civil Engineering Xi'an University of Architecture&TechnologyXi'an 710055China Dongguan Sanhang Innovation Institute Dongguan 523808China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China Institut National des Sciences Appliquées de Lyon Universitéde LyonLyon F-69621France School of Materials and Chemical Engineering Xi'an Technological UniversityXi'an710021China

Three-point bending fatigue experiments were conducted on a typical Zr-based bulk metallic glass(BMG)at ambient temperature to investigate the fatigue behavior under cyclic loading *** show that the stress amplitude-cycles to failure(S-N)curve of the Zr-based BMG is determined,and the fatigue endurance limit is 442 MPa(stress amplitude).To evaluate the probability-stress amplitude-cycles to failure(P-S-N)curve,an estimation method based on maximum likelihood was proposed,which relies on statistical principles to estimate the fatigue life of the material and allows for a reduction in the number of samples required,offering a cost-effective and efficient alternative to traditional testing *** experimental results align with the American Society for Testing and Materials(ASTM)standard,indicating the reliability and accuracy of this estimation method in evaluating the fatigue behavior of Zr-based BMG.

关键词： bulk metallic glass P-S-N curve fatigue test statistical analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Portopulmonary hypertension and hepatopulmonary syndrome

引用

World Journal of Gastroenterology 2014年第25期20卷 8072-8081页

作者： Florence Aldenkortt marc Aldenkortt Laurence Caviezel jean Luc Waeber Anne Weber Eduardo Schiffer Division of Anesthesiology Department of AnesthesiologyClinical Pharmacology and Intensive CareGeneva University Hospitals1211 GenevaSwitzerland

Portopulmonary hypertension (POPH) and hepatopulmonary syndrome (HPS) are two frequent complications of liver disease, with prevalence among liver transplant candidates of 6% and 10%, respectively. Both conditions result from a lack of hepatic clearance of vasoactive substances produced in the splanchnic territory. Subsequently, these substances cause mainly pulmonary vascular remodeling and some degree of vasoconstriction in POPH with resulting elevated pulmonary pressure and right ventricular dysfunction. In HPS the vasoactive mediators cause intrapulmonary shunts with hypoxemia. Medical treatment is disappointing overall. Whereas liver transplantation (LT) results in the disappearance of HPS within six to twelve months, its effect on POPH is highly unpredictable. Modern strategies in managing HPS and POPH rely on a thorough screening and grading of the disease’s severity, in order to tailor the appropriate therapy and select only the patients who will benefit from LT. The anesthesiologist plays a central role in managing these high-risk patients. Indeed, the important hemodynamic and respiratory modifications of the perioperative period must be avoided through continuation of the preoperatively initiated drugs, appropriate intraoperative monitoring and proper hemodynamic and respiratory therapies.

关键词： End stage liver disease Hepatopulmonary syndrome Portopulmonary Hypertension Anesthesia

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：