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Cancer Drug Resistance 2020年第4期3卷 819-831页

作者： yuriko saiki Shuto Hirota Akira Horii Department of Molecular Pathology Tohoku University School of MedicineSendaiMiyagi 980-8575Japan Office of Medical Education Tohoku University School of MedicineSendaiMiyagi 980-8575Japan Saka General Hospital ShiogamaMiyagi 985-0024Japan

Gemcitabine is a cytidine analogue frequently used in the treatment of various ***,the development of chemoresistance limits its *** resistance is regulated by various factors,including aberrant genetic and epigenetic controls,metabolism of gemcitabine,the microenvironment,epithelial-to-mesenchymal transition,and acquisition of cancer stem cell *** many situations,results using cell lines offer valuable lessons leading to the first steps of important *** this review,we mainly discuss the factors involved in gemcitabine metabolism in association with chemoresistance,including nucleoside transporters,deoxycytidine kinase,cytidine deaminase,and ATP-binding cassette transporters,and outline new perspectives for enhancing the efficacy of gemcitabine to overcome acquired chemoresistance.

关键词： Gemcitabine chemoresistance deoxycytidine kinase human equilibrative nucleoside transporter 1 cytidine deaminase ATP-binding cassette transporters metabolism

Local oxynitriding of AZ31 magnesium alloy by atmospheric-pressure plasma treatment at room temperature

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Journal of Magnesium and Alloys 2022年第7期10卷 1878-1886页

作者： Kenta Nakazawa Tatsuki Ohashi Shotaro saiki Shoichi Kikuchi Department of Mechanical Engineering Faculty of EngineeringShizuoka University3-5-1JohokuNaka-kuHamamatsu432-8561Japan Graduate School of Integrated Science and Technology Shizuoka University3-5-1 JohokuNaka-kuHamamatsu432-8561Japan

A surface-hardening treatment for AZ31 magnesium alloy using an atmospheric-pressure plasma jet(APPJ)at room temperature was *** is a potential engineering material because it is lightweight;however,magnesium alloys are difficult to heat-treat because of their low flaming *** alloy specimens were irradiated with a localized atmospheric-pressure plasma jet generated by dielectric-barrier discharge for 180 s in *** APPJ excited oxygen and nitrogen molecules in the ambient air,resulting in the formation of an oxynitrided layer;oxygen and nitrogen diffusion layer,on the surface of the magnesium *** hardness and elemental distribution for the treated surface were *** top surface of the APPJ-treated magnesium alloy achieved a maximum hardness of 108 HV,which was~1.7 times greater than that of the untreated *** analysis using an electron-probe microanalyzer revealed strong oxygen and nitrogen signals corresponding to the hardened region of the magnesium alloy,meaning that the hardness increased as a result of the formation of the oxynitrided *** proposed APPJ treatment is a promising approach for locally hardening magnesium alloys without using a heat treatment.

关键词： Magnesium alloy Oxynitriding Atmospheric-pressure plasma jet Hardness Surface modification Diffusion

New discovery of fossil cycad-like plants from the Middle Jurassic of West Liaoning,China

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Chinese Science Bulletin 2005年第16期50卷 1804-1807页

作者： WANG Yongdong ZHANG Wu ZHENG Shaolin saiki Keni'chi LI Nan Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China Shenyang Institute of Geology and Mineral Resources Ministry ofLand and Resources Shenyang 110032 China Natural History Museum and Institute Chiba 260-8086 Japan Shenzhen Xianhu Botanical Garden Shenzhen 518005 China

The Cycadales are one of the most ancient lineages of seed plants, with a fossil record that extends over 250 million years. Cycads are believed to have originated from the Late Palaeozoic, and reached its maximum diversity and distribution during the Mesozoic; however, their evolutionary history has remained relatively poorly understood. This largely results from the lack of anatomically well preserved fossil evidence and reproductive remains. In recent years, more researchers have carried out phylogenetic analysis using molecular approaches, and obtained exciting results, which broaden our knowledge of plant evolution. Meanwhile, more and more researchers have recognized that the fossil record is crucial for phylogenetic reconstruction of plant groups that have extensive evolutionary histories. Therefore, any discoveries of anatomically informative fossil with relation to cycadales or cycad-like plant taxa are of great importance to understanding of their evolutionary history.

关键词：中国辽宁植物化石种子植物侏罗纪时代

Enzyme-digested Colla Corii Asini(E’jiao) prevents hydrogen peroxide-induced cell death and accelerates amyloid beta clearance in neuronal-like PC12 cells

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Neural Regeneration Research 2020年第12期15卷 2270-2277页

作者： Li Xiao Feng Liao Ryoji Ide Tetsuro Horie Yumei Fan Chikako saiki Nobuhiko Miwa Department of Pharmacology The Nippon Dental UniversitySchool of Life Dentistry at TokyoTokyoJapan National Engineering Research Center for Gelatin-based Traditional Chinese Medicine Dong-E-E-Jiao Co.Ltd.LiaochengShandong ProvinceChina Department of Physiology The Nippon Dental UniversitySchool of Life Dentistry at TokyoTokyoJapan Research Center The Nippon Dental UniversitySchool of Life Dentistry at TokyoTokyoJapan Department of Life Sciences Prefectural University of HiroshimaHiroshimaJapan

As an aging-associated degenerative disease,Alzheimer’s disease is characterized by the deposition of amyloid beta(Aβ),oxidative stress,inflammation,dysfunction and loss of cholinergic *** Corii Asini(CCA)is a traditional Chinese medicine which has been used for feebleness-related diseases and *** might delay aging-induced degenerative changes in *** the present study,we evaluated antioxidant activity,cytoprotective effects,and Aβremovability of enzyme-digested Colla Corii Asini(CCAD).Oxygen radical absorbance capacity(ORAC)activity assay showed that,as compared to gelatins from the skin of porcine,bovine and cold water fish,CCA exhibited the highest ORAC *** ORAC activity of CCA and CCAD was increased gradually by the length of time in *** analysis by scanning electron microscopy showed that among CCA manufactured in 2008,2013,2017 and gelatin from cold water fish skin,CCA manufactured in 2008 presented the smoothest surface *** further tested the protective effects of CCAD(manufactured in 2008)and enzyme-digested gelatin from cold water fish skin(FGD)on hydrogen peroxide(H2O2)-induced cell death in nerve growth factor-differentiated neuronal-like PC12 *** blue assay showed that both FGD and CCAD at 0.5 mg/m L increased cell viability in H2O2-treated neuronal-like PC12 *** protection of CCAD was significantly superior to that of ***(Ach E)assay showed that both FGD and CCAD inhibited Ach E activity in nerve growth factor-differentiated neuronal-like PC12 cells to 89.1%and 74.5%of that in non-treated cells,*** data suggest that CCAD might be able to increase the neurotransmitter *** CCAD inhibited Ach E activity in neuronal-like PC12 cells,CCAD prevented H2O2-induced abnormal deterioration of Ach *** and neprilysin activity assay results indicated that CCAD reduced amyloid beta accumulation and increased neprilysin activity in Aβ1–

关键词： acetylcholinesterase activity Alzheimer’s disease amyloid beta clearance antioxidant Colla Corii Asini collagen neuroprotection PC12 cells

Stem cell therapy for central nerve system injuries: glial cells hold the key

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Neural Regeneration Research 2014年第13期9卷 1253-1260页

作者： Li Xiao Chikako saiki Ryoji Ide Pharmacology Department The Nippon Dental University School of Life Dentistry at Tokyo Tokyo Japan Physiology Department The Nippon Dental University School of Life Dentistry at Tokyo Tokyo Japan

Mammalian adult central nerve system （CNS） injuries are devastating because of the intrinsic difficulties for effective neuronal regeneration. The greatest problem to be overcome for CNS recovery is the poor regeneration of neurons and myelin-forming cells, oligodendrocytes. Endogenous neural progenitors and transplanted exogenous neuronal stem cells can be the source for neuronal regeneration. However, because of the harsh local microenvironment, they usually have very low efficacy for functional neural regeneration which cannot compensate for the loss of neurons and oligodendrocytes. Glial cells （including astrocytes, microglia, oligodendrocytes and NG2 glia） are the majority of cells in CNS that provide support and protection for neurons. Inside the local microenvironment, glial cells largely influence local and transplanted neural stem cells survival and fates. This review critically analyzes current finding of the roles of glial cells in CNS regeneration, and highlights strategies for regulating glial cells＇ behavior to create a permissive microenvironment for neuronal stem cells.

关键词： Neuron regeneration stem cell therapy glial cells microenvironment oligodendrocyteregeneration CNS injury

Guidance, navigation, and control of Hayabusa2 touchdown operations

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Astrodynamics 2020年第4期4卷 393-409页

作者： Fuyuto Terui Naoko Ogawa Go Ono Seiji Yasuda Tetsuya Masuda Kota Matsushima Takanao saiki Yuichi Tsuda Institute of Space and A stronautical Science Japan A erospace Exploration AgencyKanagawa 252-5210Japan The 3nd Space Technology Department Space System DirisionNEC CorporationTokyo 183-8501Japan

Hayabusa2 is a Japanese sample return mission from the asteroid *** Hayabusa2 spacecraft was launched on 3 December 2014 and arrived at Ryugu on 27 June *** stayed there until December 2019 for in situ observation and soil sample collection,and will return to the Earth in November or December *** the stay,the spacecraft performed the first touchdown operation on 22 February 2019 and the second touchdown on 11 July 2019,which were both completed *** the surface of Ryugu is rough and covered with boulders,it was not easy to find target areas for *** were several technical challenges to overcome,including demanding guidance,navigation,and control accuracy,to realize the touchdown *** this paper,strategies and technical details of the guidance,navigation,and control systems are *** flight results prove that the performance of the systems was satisfactory and largely contributed to the success of the operation.

关键词： small body exploration touchdown astrodynamics guidance navigation control

Ground-based low altitude hovering technique of Hayabusa2

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Astrodynamics 2020年第4期4卷 331-347页

作者： Yuya Mimasu Kent Yoshikawa Go Ono Naoko Ogawa Fuyuto Terui Yuto Takei Takanao saiki Yuichi Tsuda Institute of Space and Astronautical Science Japan Aerospace Exploration AgencySagamihara 252-5210Japan

The asteroid explorer Hayabusa2 carries multiple rovers and separates them to land on an asteroid *** of these rovers,called MASCOT,was developed under the international cooperation between the Deutsches Zentrum f¨ur Luft-und Raumfahrt and the Centre National d’Etudes *** rover was designed to be separated to land and perform several missions on an asteroid *** support these missions,the mother ship Hayabusa2 must separate this rover at a low altitude of approximately 50 m and hover at approximately 3 km after separation to achieve are liable communication link with *** the on-board guidance,navigation,and control(GNC)does not have an autonomous hovering function,this hovering operation is performed by ground-based *** paper introduces the GNC operation scheme for this hovering operation and reports on its flight results.

关键词： Hayabusa2 MASCOT low altitude hovering guidance,navigation,and control(GNC)

Design and flight results of GNC systems in Hayabusa2 descent operations

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Astrodynamics 2020年第2期4卷 105-117页

作者： Go Ono Fuyuto Terui Naoko Ogawa Yuya Mimasu Kent Yoshikawa Yuto Takei Takanao saiki Yuichi Tsuda Japan Aerospace Exploration Agency Sagamihara252-5210Japan

Hayabusa2 is a Japanese sample return mission from the near-Earth asteroid *** Hayabusa2 spacecraft was launched on December 3,2014,and reached the asteroid on June 27,*** remained there until November 13,2019 for in situ observation and soil sample collection and will return to the Earth in November or December *** its stay at the asteroid,Hayabusa2 performed descent operations 16 *** paper presents an overview of a guidance,navigation,and control method used in such descent *** method consists of on-board and on-ground guidance systems to control the spacecraft and an image-based navigation technique that uses a shape model and ground control points of the *** results in the first touchdown operation are shown as an example,which demonstrate that the method showed a good performance overall and contributed to the success of the mission.

关键词： small body exploration astrodynamics guidance navigation control

New discovery of fossil cycad-like plants from the Middle Jurassic of West Liaoning,China

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Science Bulletin 2005年第16期 134-137页

作者： saiki Keni’chi Natural History Museum and Institute Japan Chiba 260-8086

Perioperative Evaluation of Cerebral Blood Flow Using ^123I-labeled N-isopropyl-p-iodoamphetamine Single-Photon Emission Computed Tomography without Blood Sampling in Patients Who Underwent Carotid Artery Stenting

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Chinese Medical Journal 2016年第13期129卷 1616-1618页

作者： Naoki Matsumoto Rei Enatsu Yasuzumi Matsui Hiroyuki Ikeda Norikazu Yamana Masashi Oda Masaaki saiki Osamu Narumi Department of Neurosurgery National Hospital Organization Himeji Medical Center Himeji 670-8520 Hyogo Japan

The evaluation of regional cerebral vascular reserve （rCVR） with single-photon emission computed tomography （SPECT） is useful for predicting cerebral hyperperfusion following carotid artery stenting （CAS） and ca... 详细信息

关键词： Carotid Artery Stenosis Carotid Artery Stenting N-isopropyl-p-iodoamphetamine-Rest and True Acetazolamide Images Estimated Method Using Dynamic Acquisition Single-Photon Emission Computed Tomography