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World Journal of Gastroenterology 2006年第6期12卷 928-934页

作者： Yan Li john M Wo Mukunda b Ray Whitney Jones Ruifeng R Su Susan Ellis Robert C G Martin Division of Surgical Oncology University of Louisville School ofMedicine Louisville KY 40202 United States Division of Gastroenterology/Hepatology University of Louisville School of MedicineLouisville KY 40202 United States Department of Anatomical Pathology University of Louisville School of Medicine Louisville KY40202 United States

AIM： To investigate the expression of cyclooxygenase-2 （COX-2） and epithelial growth factor receptor （EGFR） throughout the progression of barrett＇s esophagus （bE）. METHODS： COX-2 and EGFR protein expressions were detected by using immunohistochemical method. A detailed cytomorphological changes were determined. Areas of COX-2 and EGFR expression were quantified by using computer Imaging System. RESULTS： The expressions of both COX-2 and EGFR increased along with the progression from bE to esophagus adenocarcinoma （EAC）. A positive correlation was found between COX-2 expression and EGFR expression. CONCLUSION： COX-2 and EGFR may be cooperative in the stepwise progression from bE to EAC, thereby leading to carcinogenesis.

关键词： Cycloxygenase -2 (COX-2) Epithelial growth factor receptor (EGFR) barrett's esophagus Carcinogenesis

Two remarkable epimerizations imperative for the success of an asymmetric total synthesis of (+)-aigialospirol

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Science China Chemistry 2011年第1期54卷 31-42页

作者： FIGUEROA Ruth FELTENbERGER john b. GUEVARRA Christle C. HSUNG Richard P. Division of Pharmaceutical Sciences and Department of Chemistry University of Wisconsin School of Pharmaceutical Science and Technology Tianjin University

Two remarkable epimerization processes were uncovered during our pursuit of an enantioselective synthesis of(+)-aigialospirol featuring a cyclic acetal tethered ring-closing *** modeling,we were able to turn these two unexpected epimerizations to our advantage via modeling to ensure a successful and concise total synthesis,thereby firmly establishing cyclic acetal tethered RCM as a powerful strategy in natural product *** importantly,calculations allowed us to fully understand the nature and the mechanistic course of these two epimerizations that were imperative to the total synthesis efforts.

关键词： cyclic acetal tethered RCM (+)-aigialospirol anomeric effect and epimerization.

Guild composition and habitat use of voles in 2 forest landscapes in south-eastern Norway

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Integrative Zoology 2011年第4期6卷 299-310页

作者： Lucrezia GORINI john D.C.LINNELL Luigi bOITANI Ulrike HAUPTMANN Morten ODDEN Per WEGGE Erlend b.NILSEN Department of Animal and Human biology Sapienza University of RomeRomeItaly Faculty of Applied Ecology and Agricultural Sciences Hedmark University CollegeCampus EvenstadKoppangNorway Norwegian Institute for Nature Research TrondheimNorway Department of Ecology and Natural Resource Management Norwegian University of Life SciencesÅsNorway

It is widely believed that intensive forestry has influenced small mammal population dynamics,and thereby the entire mammalian community in Fennoscandian boreal *** nature of these impacts on the different species is subject to *** live-trapped voles between 2006 and 2009 in 2 commercially harvested forests in south-eastern *** investigated the variation in vole abundance among habitat types(*** forest and clear-cut)and the hypothesis that graminivorous species such as field voles(Microtus agrestis L.)benefit from clear-cuts at the expense of forest dwellers(*** bank vole,Myodes glareolus Schreb.),using fine-scale descriptors of the ground *** could not find support for the hypothesis that field voles show a preference for clear-cuts,and their overall abundance was low,while bank voles were the dominant species in all habitat types,including clear-cuts in the peak and pre-peak *** found a positive association between bank vole abundance and bilberry(Vaccinium myrtillus L.)availability rather than a specific habitat *** field vole density in clear-cuts might be due to variation in local productivity and ground vegetation as well as to large variation in the species temporal *** latter is particularly associated with the widespread decline of field voles in *** has the potential to negatively affect bank vole population dynamics because of the negative effect on bilberry development.

关键词： bank vole bilberry clear-cut field vole forestry

ESMO 2023 pancreatic cancer guidelines signal stepwise progress

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Hepatobiliary Surgery and Nutrition 2024年第2期13卷 362-365页

作者： Christoph Springfeld Peter bailey Markus W.büchler john P.Neoptolemos Medical Oncology National Center for Tumor DiseasesHeidelberg University HospitalHeidelbergGermany Division of Applied bioinformatics The German Cancer Research Center(DKFZ)HeidelbergGermany Department of General Visceral and Transplantation SurgeryHeidelberg University HospitalHeidelbergGermany

Pancreatic ductal adenocarcinoma(PDAC)is still a devastating disease,and for those who treat PDAC patients it sometimes seems that there is little to no relevant *** excellent new ESMO clinical practice guideline by Conroy et al.(1)points to important advances in pancreatic cancer therapy that were made since the previous edition from 2015(2).According to the American Cancer Society the overall five-year survival for all stages of PDAC has improved from 5%some 30 years ago to 13%in the present *** major thrust lies in greatly improved outcomes for resectable pancreatic cancer with 5-year survival increasing from 5-10%at the beginning of this period to 30-50%due to technical improvements in surgery along with combination adjuvant chemotherapy.

关键词： Resectable borderline adjuvant neoadjuvant persister cells

Redox therapeutics in hepatic ischemia reperfusion injury

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World Journal of Hepatology 2014年第1期6卷 1-8页

作者： Rakesh P Patel john D Lang Alvin b Smith Jack H Crawford Department of Pathology Center for Free Radical Biology University of Alabama at Birmingham Department of Anesthesiology and Pain Medicine University of Washington School of Medicine Department of Anesthesiology University of Alabama Birmingham Division of Cardiothoracic Anesthesia Department of Anesthesiology University of Alabama Birmingham

Ischemia-reperfusion plays a major role in the injury experienced by the liver during transplantation. Much work has been done recently investigating the role of redox species in hepatic ischemia-reperfusion. As animal models are better characterized and developed, and more insights are gained into the pathophysiology of hepatic ischemia reperfusion injury in humans the questions into exactly how oxidants participate in this injury are becoming more refined. These questions include effects of cellular location, timing of injury, and ability of therapeutics to access this site are increasing our appreciation of the complexity of ischemia reperfusion and improving attempts to ameliorate its effects. In this review, we aim to discuss the various methods to alter redox chemistry during ischemia reperfusion injury and future prospects for preventing organ injury during hepatic ischemia reperfusion.

关键词： Ischemia Reperfusion Pre-conditioning Nitrite

Towards integrated photonic interposers for processing octave-spanning microresonator frequency combs

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Light(Science & Applications) 2021年第6期10卷 1099-1111页

作者： Ashutosh Rao Gregory Moille Xiyuan Lu Daron A.Westly Davide Sacchetto Michael Geiselmann Michael Zervas Scott b.Papp john bowers Kartik Srinivasan Physical Measurement Laboratory Microsystems and Nanotechno logy DivisionNational Institute of Standards and TechnologyGaithersburgMD 20899USA Maryland NanoCenter University of MarylandCollege Park 20742 MDUSA Joint Quantum Institute NIST/University of MarylandCollege ParkMD 20742USA Ligentec EPFL Innovation ParkBatiment CLausanneSwitzerland Physical Measurement Laboratory Time and Frequency DivisionNational Institute of Standards and TechnologyBoulderCO 80305USA Department of Physics University of ColoradoBoulderCO 80309USA Department of Electrical and Computer Engineering University of CaliforniaSanta BarbaraCA 93106USA

Microcombs-optical frequency combs generated in microresonators-have advanced tremendously in the past decade,and are advantageous for applications in frequency metrology,navigation,spectroscopy,telecommunications,and microwave ***,microcombs promise fully integrated miniaturized optical systems with unprecedented reductions in cost,size,weight,and ***,the use of bulk free-space and fiber-optic comp on ents to process microcombs has restricted form factors to the *** microcomb-based optical frequency synthesis around 1550 nm as our target application,here,we address this challenge by proposing an integrated photonics interposer architecture to replace discrete components by collecting,routing,and interfacing octave-wide microcomb-based optical signals between photonic chiplets and heterogeneously integrated ***,we con firm the requisite performa nee of the individual passive elements of the proposed interposer一octave-wide dichroics,multimode interferometers,and tunable ring filters,and implement the octave-spanning spectral filteri ng of a microcomb,central to the in terposer,using silicon n itride phot ***,we show that the thick silicon nitride needed for bright dissipative Kerr soliton generation can be integrated with the comparatively thin silicon nitride interposer layer through octave-bandwidth adiabatic evanescent coupling,indicating a path towards future system-level *** ally,we numerically confirm the feasibility of operating the proposed in terposer synthesizer as a fully assembled *** interposer architecture addresses the immediate need for on-chip microcomb processing to successfully miniaturize microcomb systems and can be readily adapted to other metrology-grade applications based on optical atomic clocks and high-precision navigation and spectroscopy.

关键词： resonator interferometer synthesizer

Effects and mechanisms of silibinin on human hepatoma cell lines

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World Journal of Gastroenterology 2007年第40期13卷 5299-5305页

作者： john J Lah Division of Gastroenterology University of CaliforniaIrvine Medical Center101 The City DriveBuilding 53Suite 113OrangeCA 92868United States

AIM： To investigate in vitro effects and mechanisms of silibinin on hepatocellular carcinoma （HCC） cell growth, METHODS： Human HCC cell lines were treated with different doses of silibinin. The effects of silibinin on HCC cell growth and proliferation, apoptosis, cell cycle progression, histone acetylation, and other related signal transductions were systematically examined. RESULTS： We demonstrated that silibinin significantly reduced the growth of HUH7, HepG2, Hep3b, and PLC/PRF/5 human hepatoma cells. Silibinin-reduced HuH7 cell growth was associated with significantly up- regulated p21/CDK4 and p27/CDK4 complexes, down- regulated Rb-phosphorylation and E2F1/DP1 complex. Silibinin promoted apoptosis of HuH7 cells that was associated with down-regulated survivin and upregulated activated caspase-3 and -9. Silibinin＇s antiangiogenic effects were indicated by down-regulated metalloproteinase-2 （MMP2） and CD34. We found that silibinin-reduced growth of HuH7 cells was associated with increased activity of phosphatase and tensin homolog deleted on chromosome ten （PTEN） and decreased p-Akt production, indicating the role of PTEN/ PI3K/Akt pathway in silibinin-mediated anti-HCC effects. We also demonstrated that silibinin increased acetylation of histone H3 and H4 （AC-H3 and AC-H4）, indicating a possible role of altered histone acetylation in silibininreduced HCC cell proliferation. CONCLUSION： Our results defined silibinin＇s in vitro anti-HCC effects and possible mechanisms, and provided a rationale to further test silibinin for HCC chemoprevention.

关键词： Hepatocellular carcinoma HuH7 cells Silibinin Chemoprevention Cell cycle Cell cycleprogression Apoptosis Acetylation of histone

Testing discrete symmetries at a super τ-charm factory

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Frontiers of physics 2016年第1期11卷 17-25页

作者： Adrian john bevan Particle Physics Research Centre Queen Mary University of London Mile End Road London E1 4NS UK

Tests of discrete symmetry violation have played an important role in understanding the structure of weak interactions in the Standard Model of particle physics. Historically, these measurements have been extensively performed in experiments with large samples of K and b mesons. A high luminosity τ-charm facility presents physicists with the opportunity to comprehensively explore discrete symmetry violation and test the Standard Model using τ leptons, charm mesons, and charmed baryons. This paper discusses several possible measurements for a future T-charm factory.

关键词： discrete symmetries P C T CP CPT violation

Prediction of plane-strain specimen geometry to efficiently obtain a forming limit diagram by Marciniak test

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Journal of Iron and Steel Research International 2018年第5期25卷 539-545页

作者： Qing-bao Yang Jun-ying Min john E. Carsley Yuan-yuan Wen bernd Kuhlenkotter Thomas b. Stoughton Jian-ping Lin School of Mechanical Engineering Tongji UniversityShanghai 201804 China General Motors Research & Development WarrenMI 48095-9055 USA Chair of Production Systems Ruhr-University BochumBochum 44780 Germany

Plane-strain forming limit strain （also known as FLD0） is an important data point on a forming limit diagram （FLD）. The effects of friction coefficients and material parameters on the specimen width associated with the FLDo （W FLD0） in Marciniak test were studied by finite element simulation. WFLD0 was expressed as a function of the Lankford coefficients, n-value, k-value and sheet thickness and validated with various sheet materials. The determination of W FLD0 is of significance not only to reduce iterative attempts to accurately obtain FLDo, but also to obtain a full valid FLD with the least number of test specimens, which largely increases the efficiency and reduces cost to experimentally measure valid FLDs.

关键词： Forming limit test ·Sheet metal· Plane-strain state· Marciniak test

Simulation of the thermodynamics of folding and unfolding of the Trp-cage mini-protein TC5b using different combinations of force fields and solvation models

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Science China Chemistry 2010年第1期53卷 196-201页

作者： ZHANG john ZengHui State Key Laboratory of Precision Spectroscopy Department of PhysicsEast China Normal University Department of Chemistry New York UniversityNew YorkNew York 10003USA

Molecular dynamics simulations based on AMbER force fields(ff96 and ff03) and generalized born models(igb1 and igb5) have been carried out in order to study folding/unfolding of the Trp-cage mini-protein *** thermodynamic properties of TC5b were found to be sensitive to the specific version of the solvation model and force field *** the ff96/igb5 combination was used,the predicted melting temperature from unfolding simulations was in good agreement with the experimental value of 315 K,but the folding simulation did not *** most stable thermodynamic profile in both folding and unfolding simulations was obtained when the ff03/igb5 combination was employed,and the predicted melting temperature was about 345 K,showing over-stabilization of the *** using the igb1 version in combination with ff96 or ff03 were difficult to converge within the simulation time limit(50 ns).

关键词： Trp-cage TC5b folding and unfolding replica-exchange melting curve implicit solvation