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Hepatobiliary & Pancreatic Diseases International 2010年第1期9卷 78-82页

作者： Cavit l kahraman Dinler O■uz Hasdemir Oktay Büyüka■ik güler Bu■dayci Department of general Surgery Abant Izzet Baysal University Medical School Department of Biochemistry Abant Izzet Baysal University Medical School

BACKgROUND:Melatonin (N-acetyl-5-methoxytripta-mine) is a free radical scavenger and a strong antioxidant,secreted by the pineal *** this study,we evaluated the effects of decreasing and increasing serum melatonin levels on malonyldialdehyde (MDA),superoxide dismutase (SOD),and reduced glutathione (gSH) levels in pancreatic tissue from rats with experimental acute ***:Experimental acute pancreatitis was induced in three groups of Wistar albino rats (10 animals per group) by pancreatic ductal *** first group had only acute pancreatitis and served as the *** pinealectomy was added to acute pancreatitis in the second group,removing the source of endogenous melatonin (low melatonin levels group).The third group was given 0.1 ml daily intraperitoneal injections of 20 mg/ml melatonin solution for one week (high melatonin levels group).The effects of melatonin levels were evaluated by comparison of the levels of MDA,SOD,and gS in pancreatic ***:We found that intraperitoneal melatonin injections decreased the levels of MDA and increased the levels of SOD and gSH in pancreatic ***:Exogenous melatonin has a preventive effect on lipid peroxidation and oxidative damage in acute pancreatitis.

关键词： pineal gland acute pancreatitis melatonin oxidative damage

Optimization of nanofiber scaffold properties towards nerve guidance channel design

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Neural Regeneration Research 2018年第7期13卷 1179-1180页

作者： graham ka-Hon Shea Francis Mok Department of Orthopaedics and Traumatology The University of Hong Kong Li ka Shing Faculty of Medicine The University of Hong Kong

Nerve guidance channels are limited by lack of topographical guidance：Treatment of sizeable nerve gaps remains problematic following peripheral nerve *** outcomes are good when neurorrhaphy,or direct end-to-end suture repair,is *** problem arises when there is significant segmental loss,which can occur following trauma as well as oncological procedures.

关键词： Optimization of nanofiber scaffold properties towards nerve guidance channel design

Bidding Strategy for Coordinated Operation of Wind Power Plants and Ngg-P2g Units in Electricity Market

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CSEE Journal of Power and Energy Systems 2022年第1期8卷 212-224页

作者： Xiang gao ka Wing Chan Shiwei Xia Xian Zhang guibin Wang Shenzhen Polytechnic ShenzhenChina and also with the Department of Electrical Engineering The Hong Kong Polytechnic UniversityHung HomHong KongChina Department of Electrical Engineering The Hong Kong Polytechnic UniversityHung HomHong KongChina School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518055China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China

The synergies between electricity and other energy resources could promote energy utilization efficiency in electricity *** this context,this paper proposes a bi-level stochastic optimization model for the joint operation of a coordinated wind power plant(WPP)and natural gas generating(Ngg)-power to gas(P2g)suppliers participating in the day-ahead(DA)market and real-time(RT)market as well as providing real-time auxiliary *** coordinated supplier’s payoff is maximized in the upper level with consideration of the uncertainties of WPP output capacity and RT electricity price,while the social welfare of the grid is maximized in the lower *** results demonstrate the effectiveness of the proposed bidding model of the coordinated WPPs and Ngg-P2g suppliers by examining its bidding behaviors and benefits with comparisons of four other bidding models.

关键词： Bi-level model bidding strategy WPP NggP2g uncertainties

kaKs_Calculator:Calculating ka and Ks Through Model Selection and Model Averaging

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genomics, Proteomics & Bioinformatics 2006年第4期4卷 259-263页

作者： Zhang Zhang Jun Li Xiao-Qian Zhao Jun Wang gane ka-Shu Wong Jun Yu Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China Beijing Instituteof genomics Chinese Academy of Sciences Beijing 101300 China graduate School of Chinese Academyof Sciences Beijing 100049 China James D. Watson Institute of genome Sciences Zhejiang UniversityHangzhou 310007 China UW genome Center University of Washington Seattle WA 98195 USA

kaKs_Calculator is a software package that calculates nonsynonymous （ka） and synonymous （Ks） substitution rates through model selection and model averaging. Since existing methods for this estimation adopt their specific mutation （substitution） models that consider different evolutionary features, leading to diverse estimates, kaKs_Calculator implements a set of candidate models in a maximum likelihood framework and adopts the Akaike information criterion to measure fitness between models and data, aiming to include as many features as needed for accurately capturing evolutionary information in protein-coding sequences. In addition, several existing methods for calculating ka and Ks are also incorporated into this software. kaKs_Calculator, including source codes, compiled executables, and documentation, is freely available for academic use at http：//***/***.

关键词： model selection model averaging AIC approximate method maximum likelihoodmethod

Structure and sequence analysis of influenza A virus nucleoprotein

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Science China(Life Sciences) 2009年第5期52卷 439-449页

作者： Ng Andy ka-Leung SHAW Pang-Chui Molecular Biotechnology Programme Department of Biochemistry and Centre for Protein Science and Crystallography The Chi-nese University of Hong Kong

Influenza A virus nucleoprotein (NP) forms homo-oligomers and multiple copies of NP wrap around genomic RNA, along with a trimeric polymerase making up ribonucleoprotein (RNP) complex. Sequence comparison of more than 2500 influenza A NP showed that this protein contains 30.1 % of polymorphic residues. NP is composed of a head and a body domain and a tail loop/ linker region. The head domain is more conserved than the body domain, as revealed from the structure-based sequence alignment. NP oligomerization is mediated by the insertion of the non-polymorphic and structurally conserved tail loop of one NP molecule to a groove of another NP. The different form of NP oligomers is due to the flexibility of the polymorphic linkers that join the tail loop to the rest of the protein. The RNA binding property of NP is known to involve the protruding element and the flexible basic loop between the head and body domains, both having high degree of primary sequence conservation. To bind RNA, NP may first capture the RNA by the flexible basic loop and then the RNA is clamped by the protruding element.

关键词： Influenza H5N1 nucleoprotein oligomerization RNA binding

Immunomodulation by mesenchymal stem cells:Interplay between mesenchymal stem cells and regulatory lymphocytes

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World Journal of Stem Cells 2016年第9期8卷 268-278页

作者： Oscar ka-Fai Ma Koon Ho Chan Department of Medicine Li Ka Shing Faculty of Medicine the University of Hong Kong

Mesenchymal stem cells(MSCs) possess immunomodulatory properties, which confer enormous potential for clinical application. Considerable evidence revealed their efficacy on various animal models of autoimmune diseases, such as multiple sclerosis, systemic lupus erythematosus and uveitis. MSCs elicit their immunomodulatory effects by inhibiting lymphocyte activation and proliferation, forbidding the secretion of proinflammatory cytokines, limiting the function of antigen presenting cells, and inducing regulatory T(Treg) and B(Breg) cells. The induction of Treg and Breg cells is of particular interest since Treg and Breg cells have significant roles in maintaining immune tolerance. Several mechanisms have been proposed regarding to the MSCs-mediated induction of Treg and Breg cells. Accordingly, MSCs induce regulatory lymphocytes through secretion of multiple pleiotropic cytokines, cell-to-cell contact with target cells and modulation of antigen-presenting cells. Here, we summarized how MSCs induce Treg and Breg cells to provoke immunosuppression.

关键词： Mesenchymal stem cells Regulatory T cells Regulatory B cells Immunomodulation Autoimmunity

Losses Estimation in Transonic Wet Steam Flow through Linear Blade Cascade

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Journal of Thermal Science 2015年第2期24卷 109-116页

作者： Sawomir Dykas Mirosaw Majkut Micha Strozik Krystian Smoka Institute of Power Engineering and Turbomachinery Silesian University of Technology

Experimental investigations of non-equilibrium spontaneous condensation in transonic steam flow were carded out in linear blade cascade. The linear cascade consists of the stator blades of the last stage of low pressure steam turbine. The applied experimental test section is a part of a small scale steam power plant located at Silesian Uni- versity of Technology in gliwice. The steam parameters at the test section inlet correspond to the real conditions in low pressure part of 200MWe steam turbine. The losses in the cascade were estimated using measured static pressure and temperature behind the cascade and the total parameters at inlet. The static pressure measurements on the blade surface as well as the Schlieren pictures were used to assess the flow field in linear cascade of steam turbine stator blades.

关键词： wet steam condensation transonic flow losses

The role of LIN28B in tumor progression and metastasis in solid tumor entities

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Oncology Research 2023年第2期31卷 101-115页

作者： TABEA gEWALT ka-WON NOH LYDIA MEDER Department I of Internal Medicine Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany Center for Molecular Medicine Cologne University of CologneCologneGermany Institute for Pathology Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany Mildred Scheel School of Oncology Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany

LIN28B is an RNA-binding protein that targets a broad range of microRNAs and modulates their maturation and *** normal conditions,LIN28B is exclusively expressed in embryogenic stem cells,blocking differentiation and promoting *** addition,it can play a role in epithelial-to-mesenchymal transition by repressing the biogenesis of let-7 *** malignancies,LIN28B is frequently overexpressed,which is associated with increased tumor aggressiveness and metastatic *** this review,we discuss the molecular mechanisms of LIN28B in promoting tumor progression and metastasis in solid tumor entities and its potential use as a clinical therapeutic target and biomarker.

关键词： Cancer Metastasis LIN28B Let-7 Stemness EMT Resistance

A rationale for the development of thermally stable nanostructured CeO_2-ZrO_2-containing mixed oxides

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Journal of Rare Earths 2008年第2期26卷 136-140页

作者： Roberta Di Monte Jan kapar Heather Bradshaw Colin Norman Department of Chemistry Sciences Interuniversity Consortium INCA University of Trieste Via L.Giorgieri34127 Trieste Italy MEL Chemicals P.O. Box 6 Clifton Junction SwintonManchester M27 8LS England

CeO2-ZeO2 solid solutions are extensively used as oxygen storage promoters in the current automotive three-way catalysts. High thermal stability of the textural properties is one of the most important requirements for practical application since temperatures up to 1273 K are easily experienced by these materials under real working conditions. In the present paper, we investigated how hydrothermal treatments applied to cakes of doped and undoped ZrO2-rich CeO2-ZrO2 precursors might improve the thermal stability of the final CeO2-ZrO2 solid solution. A rationale was developed that allowed to correlate the morphology of the hydrothermaUy treated cake with the thermal stability at 1273 K of the final product, which did not depend on the composition of the mixed oxides.

关键词： CeO2-ZrO2 mixed oxides CeO2-ZrO2 solid solution CeO2-ZrO2 mixed oxides, thermal stability of three-way catalysts oxygen storage capacity rare earths

Command and Control Cities in global Space-economy Before and after 2008 geo-economic Transition

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Chinese geographical Science 2012年第3期22卷 334-342页

作者： Ernest ka Shing LEE Simon Xiaobin ZHAO Yang XIE International Center for China Development Studies & Department of geography Faculty of Social Sciences the University of Hong Kong Hong Kong China Department for Rural Economic Development Research Center of the State Council Beijing 100010 China

The global economic downturn caused primarily by the US sub-prime mortgage crisis in 2007 engendered revenue loss of the multinational corporations. Existing studies have yet to depict the detrimental impacts on city＇s command and control functions induced by the sub-prime mortgage crisis together with its residual wave of global economic recession on the global spatial economy. Recent and previous studies have produced an ＇instant history＇ of the global spatial economy before the global economic downturn undermines the global economy in late 2008. How- ever, the waxes and wanes of major cities＇ command and control functions on the global economic arena before and after the outbreak of financial crisis and its associated geo-economic transitions are still poorly understood. This paper attempts to contribute a new set of customized data to update and fill in the gap in the literature with the investigation of the command and control functions of cities arotmd the world from 2005 to 2009. Particular attentions are paid to the time-space relationship of the geo-economic transition that can capture the recent historical images of the com- mand and control situation of different cities in the world.

关键词： global space-economy command and control cities geo-economic transition China