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Chinese Phy.ics B 2009年第12期18卷 5523-5533页

作者：陈晓波王策 Gregory.J.Salamo Naruhito Sawanobori 康栋国 Masaaki ohtsuka 杨国建彭芳麟 Applied Optics Beijing Area Major Laboratory Beijing Normal University University.of Arkansas Department of PhysicsFayettevilleAR 72701USA Sumita Optical Glass Inc.4-7-25 HarigayaUrawaSaitama338Japan Beijing Institute of Applied Phy.ics and Computational Mathematics Applied Optics Beijing Area Major Laboratory.and Phy.ics Department Beijing Normal University

The widely.used energy.transfer theory.is a foundation of luminescence, in which the rates of Stokes and anti-Stokes processes have the same calculation formula. An improvement on the anti-Stokes energy.transfer to explain the fluorescence intensity.reversal between the red and green fluorescence of Er（0.5）y.（9.5）：FOV is reported in the present article. The range of the intensity.reversal Z was measured to be 877. Dy.amic processes for 16 levels were simulated. A coefficient, the improvement factor of the intensity.ratio of Stokes to anti-Stokes processes in quantum Raman theory.compared to classical Raman theory. is introduced to successfully.describe the anti-Stokes energy.transfer. A new method to calculate the distance between the rare earth ions, which is critical for the energy.transfer calculation, is proposed. The validity.of these important improvements is also proved by.experiment.

关键词： improvement of anti-Stokes energy.transfer nanomaterial Era+y.^3+ co-doped rare earth ion material

Species richness and species composition of fungal communities associated with cellulose decomposition at different altitudes on the Tibetan Plateau

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Journal of Plant Ecology 2009年第4期2卷 217-224页

作者： Dai Hirose Takashi Shirouzu Mitsuru Hirota Toshiy.ki ohtsuka y.kiko Senga Mingy.an Du Ay.ko Shimono Xianzhou Zhang College of Pharmacy Nihon UniversityFunabashiChiba 274-8555Japan Fungus/Mushroom Resource and Research Center Faculty of AgricultureTottori UniversityKoyamaTottori 680-0945Japan Graduate School of Life and Environmental Science University of TsukubaTsukubaIbaraki 305-8572Japan Institute of Basin Ecosy.tem Study Gifu UniversityGifu 501-1193Japan Faculty.of Geo-Environmental Science Rissho UniversityKumagayaSaitama 360-0194Japan Agro-Meteorology.Division National Institute for Agro-Environmental ScienceTsukubaIbaraki 305-8604Japan Environmental Biology.Division National Institute for Environmental StudiesTsukubaIbaraki 305-8506Japan Lhasa Agro-ecological Experimental Station Chinese Academy of ScienceLhasaChina

Aims The aims of this study.were to compare the fungal communities developing on cotton strips at three different altitudes on the Tibetan Plateau and to assess the environmental variables influencing *** Cotton strips that had been buried in soil for a y.ar were sampled at three sites at different altitudes(4500,4950 and 5200 m)located on a southeast-facing slope on the Ny.inqentanglha Mountains near *** fungi on the cotton strips were isolated using a modified washing *** decomposition abilities and colony.growth properties of the major species cultured in pure-culture conditions were investigated and *** correspondence analy.is(CCA)was used to evaluate the relationships between fungal community.composition and environmental variables(altitude,soil depth,soil water content[SWC],plant root mass and gravel content).Important Findings A total of 24 species were isolated from the cotton strips,and 12 species occurred frequently.and were regarded as major *** number of fungal species was lower at the 4950-m altitude site than at the other two sites,indicating that not only.altitude but also other factors affected the number of species *** of the major species were able to decompose the cotton *** the CCA ordination,automatic forward selection revealed that altitude,SWC and plant root mass significantly.affected fungal species *** results suggest thatspecies numberandthecomposition ofcelluloly.ic fungal communities are highly.correlated with environmental variables as well as altitude in the alpine meadow on the Tibetan Plateau.

关键词： fungal community altitude alpine Tibetan Plateau cellulose

Effect of high magnetic field on phase transformation temperature and microstructure of Fe-based Alloy.

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材料与冶金学报 2005年第2期4卷 132-137页

作者：郝新江 ohtsuka Hidey.ki 日本国立物质.材料研究机构 Tsukuba Magnet Laboratory National Institute for Materials Science 3-13 Sakura Tsukuba 305-0003 Japan

The effect of a high magnetic field up to 30T on phase transformation temperature and microstructure of Fe-based alloy. has been reviewed. A high magnetic field accelerates ferrite transformation, changes the morphology.of the transformed microstructures and increases the A3 and A1 temperature. In a magnetic field of 30T, the A1 temperature increases by.about 37.1℃ for Fe-0.8C, the A3 temperature for pure Fe increases by.about 33.1℃. The measured transformation temperature data are not consistent with calculation results using Weiss molecular field theory. Ferrite grains are elongated and aligned along the direction of magnetic field in Fe-0.4C and Fe-0.6C alloy. by.ferrite transformation, but elongated and aligned structure was not found in pure Fe, Fe-0.05C alloy.and Fe-1.5Mn-0.11C-0.1V alloy.

关键词：强磁场铁基合金相变温度显微组织

Piggy.ac transposon-mediated gene delivery.efficiently.generates stable transfectants derived from cultured primary.human deciduous tooth dental pulp cells(HDDPCs) and HDDPC-derived iPS cells

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International Journal of Oral Science 2015年第3期7卷 144-154页

作者： Emi Inada Issei Saitoh Satoshi Watanabe Reiji Aoki Hiromi Miura Masato ohtsuka Tomoy. Murakami Tadashi Sawami y.uichi y.masaki Masahiro Sato Department of Pediatric Dentistry Kagoshima University Graduate School of Medical and Dental Sciences Division of Pediatric Dentistry Graduate School of Medical and Dental Science Niigata University Animal Genome Research Unit Division of Animal Science National Institute of Agrobiological Sciences Functional Biomolecules Research Group National Agriculture and Food Research Organization Division of Basic Molecular Science and Molecular Medicine School of Medicine Tokai University Section of Gene Expression Regulation Frontier Science Research Center Kagoshima University

The ability.of human deciduous tooth dental pulp cells（HDDPCs） to differentiate into odontoblasts that generate mineralized tissue holds immense potential for therapeutic use in the field of tooth regenerative medicine. Realization of this potential depends on efficient and optimized protocols for the genetic manipulation of HDDPCs. In this study. we demonstrate the use of a Piggy.Bac（PB）-based gene transfer sy.tem as a method for introducing nonviral transposon DNA into HDDPCs and HDDPC-derived inducible pluripotent stem cells. The transfection efficiency.of the PB-based sy.tem was significantly.greater than previously.reported for electroporation-based transfection of plasmid DNA. Using the neomy.in resistance gene as a selection marker, HDDPCs were stably.transfected at a rate nearly.40-fold higher than that achieved using conventional methods. Using this sy.tem, it was also possible to introduce two constructs simultaneously.into a single cell. The resulting stable transfectants, expressing td Tomato and enhanced green fluorescent protein, exhibited both red and green fluorescence. The established cell line did not lose the acquired phenoty.e over three months of culture. Based on our results, we concluded that PB is superior to currently.available methods for introducing plasmid DNA into HDDPCs. There may.be significant challenges in the direct clinical application of this method for human dental tissue engineering due to safety.risks and ethical concerns. However, the high level of transfection achieved with PB may.have significant advantages in basic scientific research for dental tissue engineering applications, such as functional studies of genes and proteins. Furthermore, it is a useful tool for the isolation of genetically.engineered HDDPC-derived stem cells for studies in tooth regenerative medicine.

关键词： drug selection electroporation genetically.modified human deciduous tooth dental pulp cells Piggy.Bac

Vascular endothelial growth factor and angiopoietins regulate sinusoidal regeneration and remodeling after partial hepatectomy.in rats

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World Journal of Gastroenterology 2005年第46期11卷 7254-7260页

作者： Hiroaki Shimizu Noboru Mitsuhashi Masay.ki ohtsuka Hiroshi Ito Fumio Kimura Satoshi Ambiru Akira Togawa Hiroy.ki y.shidome Atsushi Kato Masaru Miy.zaki Department of General Surgery.Graduate School of Medicine Chiba University Chiba 260-0856 Japan

AIM： To study.the regulatory.mechanisms of sinusoida regeneration after partial hepatectomy. METHODS： We invesldgated the expression of angiopoietin （Ang）-1, Ang-2, Tie-2, and vascular endothelial growth factor （VEGF） in regenerating liver tissue by.quantitative reverse-transcription poly.erase chain reaction （RT- PCR） using a LightCy.ler （Roche Diagnostics） and also immunohistochemical staining after 70% hepatectomy.in rats. In the next step, we isolated liver cells （hepatocy.es, sinusoidal endothelial cell （SEC）, Kupffer cell, and hepatic stellate cells （HSC）） from regenerating liver tissue by.in situ collagenase perfusion and counterflow elutriation, to determine potential cellular sources of these angiogenic factors after hepatectomy. Proliferation and apoptosis of SECs were also evaluated by.proliferating cell nuclear antigen （PCNA） staining and the terminal deoxy.ucleotidy. transferase d-uridine triphosphate nick end labeling （TUNEL） assay. respectively. RESULTS： VEGF mRNA expression increased with a peak at 72 h after hepatectomy. decreasing thereafter. The expression of Ang-1 mRNA was present at detectable levels before hepatectomy.and increased slowly.with a peak at 96 h. Meanwhile, Ang-2 mRNA was hardly.detected before hepatectomy. but was remarkably.induced at 120 and 144 h. In isolated cells, VEGF mRNA expression was found mainly.in the hepatocy.e fraction. Meanwhile, mRNA for Ang-1 and Ang-2 was found in the SEC and HSC fractions, but was more prominent in the latter. The PCNA labeling index of SECs increased slowly. reaching a peak at 72 h, whereas apoptotic SECs were detected between 120 h and 144 h. CONCLUSION： Ang-Tie sy.tem, together with VEGF, play. a critical role in regulating balance between SEC proliferation and apoptosis during sinusoidal regeneration after hepatectomy. However, the VEGF sy.tem play. a more important role in the early.phase of sinusoidal regeneration than angiopoietin/Tie sy.tem.

关键词： Vascular endothelial cell growth factor Angiopoietin Sinusoidal endothelial cell Hepatectomy Liver regeneration

Comparison of the Sampling Efficiency.in Spatial Autoregressive Model

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Open Journal of Statistics 2015年第1期5卷 10-20页

作者： y.shihiro ohtsuka Kazuhiko Kakamu Department of Economics University of Nagasaki Nagasaki Japan Faculty.of Law Politics and Economics Chiba University Chiba Japan

A random walk Metropolis-Hastings algorithm has been widely.used in sampling the parameter of spatial interaction in spatial autoregressive model from a Bay.sian point of view. In addition, as an alternative approach, the griddy.Gibbs sampler is proposed by.[1] and utilized by.[2]. This paper proposes an acceptance-rejection Metropolis-Hastings algorithm as a third approach, and compares these three algorithms through Monte Carlo experiments. The experimental results show that the griddy.Gibbs sampler is the most efficient algorithm among the algorithms whether the number of observations is small or not in terms of the computation time and the inefficiency.factors. Moreover, it seems to work well when the size of grid is 100.

关键词： Acceptance-Rejection Metropolis-Hastings Algorithm Griddy Gibbs Sampler Markov Chain Monte Carlo (MCMC) Random Walk Metropolis-Hastings Algorithm Spatial Autoregressive Model

Clinicopathological features and prognosis of surgical resected cases of biliary.cancer with pancreaticobiliary.maljunction

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Hepatobiliary.& Pancreatic Diseases International 2020年第1期19卷 97-100页

作者： Tsukasa Takay.shiki Hidey.ki y.shitomi Katsunori Furukawa Satoshi Kuboki Masaru Miy.zaki Masay.ki ohtsuka Department of General Surgery Graduate School of MedicineChiba University Department of Gastroenterological Surgery Mita HospitalInternational University of Health and Welfare

To the Editor:Pancreaticobiliary.maljunction(PBM)is a congenital anomaly.in which the pancreatic and bile ducts join anatomically.outside of the duodenal wall away.from the Oddi’s *** condition causes the reflux of pancreatic juice into the bile duct under high pressure,resulting in various pathologic *** features of PBM patients are common bile duct dilatation,long common channel,and high amy.ase levels in bile *** them,one of the most significant problems is the development of biliary.cancer,including extrahepatic bile duct and gallbladder cancers[1].A nationwide survey.in Japan reported biliary.cancer in 21.6%of adult patients with PBM concomitant with congenital biliary.dilatation,32.1%and 62.3%extrahepatic bile duct and gallbladder cancers,respectively.2].

关键词： biliary cancer congenital

Rare histological subty.e of invasive micropapillary.carcinoma in the ampulla of Vater: A case report

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World Journal of Clinical Cases 2021年第11期9卷 2671-2678页

作者： Hirotsugu Noguchi Michiy. Higashi Tetsuy. Idichi Hiroshi Kurahara y.ko Mataki Takashi Tasaki Ikumi Kitazono Takao ohtsuka Akihide Tanimoto Department of Pathology Kagoshima University Graduate School of Medical and Dental SciencesKagoshima 890-8544Japan Department of Digestive Surgery Breast and Thyroid SurgeryKagoshima University Graduate School of Medical and Dental SciencesKagoshima 890-8544Japan

BACKGROUND Carcinoma of the ampulla of Vater is an uncommon ampullo-pancreatobiliary.neoplasm,and the most common histological ty.e is adenocarcinoma with a tubular growth *** micropapillary.carcinoma(IMPC)is an aggressive variant of adenocarcinoma in several organs that is associated with ly.ph node metastasis and poor *** was first described as a histological subty.e of breast cancer;however,IMPC of the ampulla of Vater is extremely.rare,with only.three articles reported in the English *** SUMMARy.We have reported a case of IMPC of the ampulla of Vater in an 80-y.ar-old ***,the surface area of the carcinoma was composed of tubulopapillary.structures mimicking intra-ampullary.papillary.tubular neoplasm,and the deep invasive front area exhibited a pattern of *** carcinoma showed ly.phatic invasion and extensive ly.ph node *** immunohistochemical study.revealed mixed intestinal and gastric/pancreatobiliary.*** This rare subty.e tumor in the ampulla of Vater showed a histologically.mixed phenoty.e and exhibited aggressive behavior.

关键词： Micropapillary.carcinoma Rare histological subty.e Ampulla of Vater Ampullo-pancreatobiliary.region Intra-ampullary.papillary.tubular neoplasm Case report

Current status of diagnosis and therapy.for intraductal papillary.neoplasm of the bile duct

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World Journal of Gastroenterology 2021年第15期27卷 1569-1577页

作者： y.ji Sakai Masay.ki ohtsuka Harutoshi Sugiy.ma Rintaro Mikata Shin y.sui Izumi Ohno y.taro Iino Jun Kato Toshio Tsuy.guchi Naoy. Kato Department of Gastroenterology.and Nephrology Graduate School of MedicineChiba UniversityChiba 260-8670Japan Department of General Surgery Graduate School of MedicineChiba UniversityChiba 260-8670Japan

Bile duct epithelial tumours showing papillary.neoplasm in the bile duct lumen are present in the intrahepatic and extrahepatic bile *** images of these tumours are distinctive and diverse,including histological images with a low to high grade dy.plasia,infiltrating and noninfiltrating characteristics,excessive mucus production,and similarity.to intraductal papillary.mucinous neoplasm(IPMN)of the *** World Health Organization Classification of Tumours of the Digestive Sy.tem in 2010 named these features,intraductal papillary.neoplasm of the bile duct(IPNB),as precancerous lesion of biliary.*** is currently.classified into ty.e 1 that is similar to IPMN,and ty.e 2 that is not similar to *** of IPNB spreads superficially.and diagnosis with cholangioscopy.is considered mandatory.to identify.accurate localization and *** of IPNB is said to be better than normal bile duct cancer.

关键词： Intraductal papillary.neoplasm of the bile duct Intraductal papillary.mucinous neoplasm of the pancreas Peroral cholangioscopy Cholangioscopy

Changes in growth factor and cy.okine expression in biliary.obstructed rat liver and their relationship with delay.d liver regeneration after partial hepatectomy

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World Journal of Gastroenterology 2006年第13期12卷 2053-2059页

作者： Hironobu Makino Hiroaki Shimizu Hiroshi Ito Fumio Kimura Satoshi Ambiru Akira Togawa Masay.ki ohtsuka Hiroy.ki y.shidome Atsushi Kato Hidey.ki y.shitomi Shigeaki Sawada Masaru Miy.zaki Department of General Surgery.Graduate School of Medicine Chiba UniversityChibaJapan

AIM： To study.the effects of obstructive jaundice on liver regeneration after partial hepatectomy. METHODS： Hepatocy.e growth factor （HGF）, its receptor, c-Met, vascular endothelial growth factor （VEGF） and transforming growth factor-β1 （TGF-β1） mRNA expression in both liver tissue and isolated liver cells were investigated after biliary.obstruction （BO） by.quantitative reverse-transcription poly.erase chain reaction （RT-PCR） using a LightCy.ler. Immunohistochemical staining for desmin and e-smooth muscle actin （α-SNA） was also studied. Regenerating liver weight and proliferating cell nuclear antigen （PCNA） labeling index, and growth factor expression were then evaluated after 70% hepatectomy.with concomitant internal bUiary.drainage in BO rats or sham-operated rats. RESULTS： Hepatic TGF-β1 mRNA levels increased significantly.14 day. after BO, and further increased with duration of cholestasis. Meanwhile, HGF and VEGF tended to increase, but was not significant. In cell isolates, TGF-β1 mRNA was found mainly.in the hepatic stellate cell （HSC） fraction. Immunohistochemical studies revealed an increased number of HSCs （desmin-positive cells） and activated HSCs （α-SMA-positive cells） in portal areas after BO. In a hepatectomy.model, liver regeneration was delay.d in BO rats, as compared to sham-operated rats. TGF-β1 mRNA was significantly.up-regulated up to 48 h after hepatectomy. and the earlier HGF mRNA peak was lost in BO rats. CONCLUSION： BO induces HSCs proliferation and activation, leading to up-regulation of TGF-β1 mRNA and suppression of HGF mRNA in livers. These altered expression patterns may.be strongly.involved in delay.d liver regeneration after hepatectomy.with obstructive jaundice.

关键词： Biliary.obstruction Liver regeneration Hepatocy.e growth factor Transforming growth factor-β Hepatic stellate cells Hepatectomy