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TENSILE PROPERTIES AND CREEP RESISTANCE OF AZ91 ALLOY CONTAINING ANTIMONY

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Acta Metallurgica Sinica(English Letters) 2000年第3期13卷 867-871页

作者： Yuan, G.Y. Sun, Y.S. Zhang, w.M. Bao, Y.H. Southeastern Univ Nanjing China

Small amount of antimony addition to the Mg-9Al-0.8Zn-0.2Mn(AZ91) alloy results in the obvious increase of tensile strength at both ambient and elevated temperatures. The creep resistance at the temperatures up to 200°C is also improved significantly by antimony addition. Microstructural observations revealed that the addition of antimony modifies morphology of the β(Mg17Al12) phase and causes the formation of some rod-shaped precipitates Mg3Sb2 at grain boundaries. These precipitates have high thermal stability and play an important role for strengthening grain boundaries at elevated temperatures.

关键词： Aluminum alloys Antimony Automobile materials Creep testing Grain boundaries Microstructure Tensile stress Tensile testing Zinc alloys

Hepatocellular carcinoma in patients with autoimmune hepatitis

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world Journal of Gastroenterology 2009年第5期15卷 578-582页

作者： Andreas Teufel Arndt weinmann Catherine Centner Anja Piendl Ansgar w Lohse Peter R Galle Stephan Kanzler Department of Medicine I Johannes Gutenberg University Mainz 55101 Germany Department of Medicine I University of Hamburg Hamburg 22527 Germany

AIM: To evaluate and confirm the low incidence of hepatocellular carcinoma (HCC) in patients with autoimmune hepatitis (AIH). At present only very few cases of HCC in patients with AIH and definite exclusion of chronic viral hepatitis have been published, suggesting that HCC due to AIH is rare. METHODS: In order to further investigate the incidence of HCC in patients with AIH, we reviewed our large cohort of 278 patients with AIH. RESULTS: Eighty-nine patients (32%) were diagnosed with liver cirrhosis, a preneoplastic condition for HCC. we studied a total of 431 patient years of cirrhosis in these patients, an average 4.8 years per patient. During this period none of the patients of our own study cohort developed HCC. However, three patients with HCC due to AIH associated liver cirrhosis were referred to our department for further treatment of HCC. In all three patients chronic viral hepatitis was excluded. CONCLUSION: we conclude that HCC may under rare circumstances develop due to chronic AIH dependent liver cirrhosis. Compared to other causes of liver cirrhosis such as chronic viral hepatitis, alcohol, or hemochromatosis, the incidence of HCC is significantly lower. Pathophysiological differences between AIH and chronic viral hepatitis responsible for differences in the incidence of HCC are yet to be further characterized and may lead to new therapeutic concepts in prevention and treatment of liver cancer.

关键词： Autoimmune hepatitis Hepatocellularcarcinoma Hepatic C virus Hepatic B virus Livercirrhosis

SUPERPLASTICITY OF A Ni-28.5Al-20.4Fe INTERMETALLIC ALLOY

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Acta Metallurgica Sinica(English Letters) 2000年第3期13卷 888-892页

作者： Zhou, w.L. Guo, J.T. Chen, R.S. Zhou, J.Y. Inst of Metal Research Chinese Acad of Sciences Shenyang China

Our previous investigation examined the superplastic behavior of an extruded Ni-28.5Al-20.4Fe alloy. Its tensile properties were determined at temperature from 1123 K to 1323 K and initial strain rates from 1.04×10-2s-1 to 1.04×10-4s-1. A maximum elongation of 233% was obtained at 1123 K and a strain rate of 5.2×10-4s-1. Furthermore, microstructural features, such as decrease in the average grain size after deformation at 850 °C and 980 °C, the presence of many dislocation-free grains adjacent to grains with a high dislocation density, indicate that dynamic recrystallization has occurred as an efficient accommodation mechanism. SEM examination of the fracture sample after superplastic deformation reveals many voids on the fracture surface. By correlating with the result of TEM observation, it is suggested that the superplastic deformation in this alloy should be controlled by a grain boundary sliding-based mechanism accommodated by the movement of dislocation and dynamic recrystallization.

关键词： Activation energy Aluminum alloys Intermetallics Iron alloys Microstructure Recrystallization (metallurgy) Superplasticity Tensile testing

藏红花苷缓解血管紧张素Ⅱ诱导大鼠血管平滑肌细胞炎症反应的研究

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中国临床药理学杂志 2021年第24期37卷 3354-3357页

作者：张传扩马礼坤安徽医科大学附属安徽省立医院心血管内科安徽合肥230001 六安市第四人民医院心血管内科安徽六安237006

目的探讨藏红花苷对血管紧张素Ⅱ诱导大鼠血管平滑肌细胞(RVSMCs)炎症的缓解作用及抗炎机理。方法将RVSMCs细胞随机分为空白组、对照组和低、中、高剂量实验组。空白组给予生理盐水处理,对照组给予100 nmol·L^(-1)血管紧张素Ⅱ处理24 h... 详细信息

目的探讨藏红花苷对血管紧张素Ⅱ诱导大鼠血管平滑肌细胞(RVSMCs)炎症的缓解作用及抗炎机理。方法将RVSMCs细胞随机分为空白组、对照组和低、中、高剂量实验组。空白组给予生理盐水处理,对照组给予100 nmol·L^(-1)血管紧张素Ⅱ处理24 h,低、中、高剂量实验组先分别给予8,16,32μmol·L^(-1)藏红花苷处理2 h后,再用100 nmol·L^(-1)血管紧张素Ⅱ处理24 h。用酶联免疫吸附测定法(ELISA)试剂盒测定各组肿瘤坏死因子-α(TNF-α)、白细胞介素-6 (IL-6)水平;用比色法测定各组一氧化氮(NO)水平;用蛋白免疫印迹法测定各组炎症相关蛋白磷酸化核细胞转录因子κB抑制蛋白(p-IκBα)、核转录因子p65、磷酸化蛋白激酶B (p-AKT)表达。结果空白组、对照组、中、高剂量实验组的NO水平分别为(3.33±0.14),(16.38±1.51),(11.51±0.88)和(8.92±0.31)μmol·L^(-1);p-IκBα相对表达量分别为0.24±0.06,1.02±0.04,0.67±0.06和0.32±0.02;核p65转录因子相对表达量分别为0.21±0.03,1.01±0.06,0.74±0.07和0.67±0.04;p-AKT相对表达量分别为0.19±0.02,1.02±0.03,0.75±0.04和0.64±0.05。上述指标,对照组与空白组比较,差异均有统计学意义(均P<0.05);中、高剂量实验组与对照组比较,差异均有统计学意义(均P<0.05)。结论藏红花苷通过下调NF-κB/AKT信号通路缓解血管紧张素Ⅱ诱导的大鼠血管平滑肌细胞的炎症反应。

关键词：藏红花苷血管平滑肌细胞炎症血管紧张素Ⅱ 核细胞转录因子/蛋白激酶B

Seroepidemiology of hepatitis A virus in Kuwait

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world Journal of Gastroenterology 2009年第1期15卷 102-105页

作者： Jameela Alkhalidi Bader Alenezi Seham Al-mufti Entisar Hussain Haifa Askar Nyingi Kemmer Guy w Neff Thuniyan Al-Ghanim GI Center & University of KuwaitPO Box 4077 Safat 13041 Kuwait University of Cincinnati Cincinnati OH 45267-0576 United States

AIM: To fi nd the current seroepidemiology of hepatitis A virus (HAV) in ***: A total of 2851 Kuwaitis applying for new jobs were ***: HAV-positive cases were 28.8%; 59% were males and 41% were females. The highest prevalence was in the Ahmadi area. High prevalence was among the group of non-educated rather than educated parents. This is the fi rst study in Kuwait demonstrating the shifting epidemiology of ***: This study reflects the need of the Kuwaiti population for an HAV vaccine.

关键词： Hepatitis A virus Fulminant Liver Failure Hepatitis A virus vaccine Kuwait

Circle of willis variants are not associated with thrombectomy outcomes

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Stroke & Vascular Neurology 2021年第2期6卷 310-313页

作者： Thomas Seifert-Held Katharina Eberhard Soren Christensen Edith Hofer Christian Enzinger Gregory w Albers Maarten Lansberg Department of Neurology Medical University of GrazGrazAustria Core Facility Computational Bioanalytics Center for Medical ResearchMedical University of GrazGrazAustria Department of Neurology&Neurological Sciences Stanford UniversityStanfordCaliforniaUSA

Background The circle of willis(COw)is part of the brain collateral *** absence of COw segments may affect functional outcome in patients with ischaemic stroke undergoing endovascular *** In 182 patients in the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution 2 Study and the CT Perfusion to Predict Response to Recanalisation in Ischaemic Stroke Project,COw anatomy was evaluated on postinterventional magnetic resonance *** absence of the posterior communicating artery or the first segments of posterior or anterior cerebral arteries ipsilateral to the ischaemic infarction was rated as an incomplete *** regression was applied to evaluate an association with the patients’modified Rankin scale(mRS)at 90 days after stroke Results An incomplete ipsilateral COw was not predictive of the patients’mRS at 90 days after *** associations were shown for the patients’baseline National Institutes of Health Stroke Scale(NIHSS),age and reperfusion *** effect size suggests that a significant association of an incomplete COw with the mRS at 90 days may be obtained in cohorts of more than 3000 *** Compared with the established predictors NIHSS,age and reperfusion status,an incomplete COw is not associated with functional outcome after endovascular therapy.

关键词： willis anatomy incomplete

Enhanced helium ion irradiation tolerance in a Fe-Co-Ni-Cr-Al-Ti high-entropy alloy with L12 nanoparticles

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Journal of Materials Science & Technology 2023年第12期143卷 169-177页

作者： Y.L.Zhao F.L.Meng T.Yang J.H.Luan S.F.Liu G.M.Yeli w.T.Lin w.H.Liu X.J.Liu C.T.Liu J.J.Kai School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China School of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Materials Science and Engineering Mechanical Behavior Division of Shenyang National Laboratory for Materials ScienceCity University of Hong KongHong KongChina Department of Mechanical Engineering City University of Hong KongHong KongChina Institute of Nuclear&New Energy Technology Tsinghua UniversityBeijing 100084China

L12-strengthened high entropy alloys(HEAs)with excellent room and high-temperature mechanical prop-erties have been proposed as promising candidates as structural materials for advanced nuclear ***,knowledge about their radiation response is fairly *** the present work,a novel HEA with a high density of L12 nanoparticles was irradiated with He ion at 500°*** electron microscope(TEM)and atom probe tomography(APT)were employed to study the evolution of mi-crostructural stability and radiation-induced *** to the single-phase FeCoNiCr HEA,the main microstructural features were numerous large faulted dislocation loops and helium *** the irradiation resistance of the present L12-strengthened HEA is much improved in terms of reduced bubble size,which could be attributed to the considerable He trapping efficiency of the coherent pre-cipitate/matrix interface and the enhanced capability of the interface for damage elimination when the matrix channel width is *** analysis revealed that an inverse-Kirkendall-mechanism-dominated radiation-induced segregation(RIS)occurs around bubbles,where a significant Co enrichment and Ni de-pletion can be clearly *** addition,the competing dynamics of ballistic mixing and elemental clustering that raised from the irradiation-enhanced diffusion in a highly supersaturated matrix,along with the low precipitation nucleation barrier due to the small lattice misfit,lead to a dynamical pre-cipitation dissolution and re-precipitation appears under *** a promising phenomenon is expected to promote a potential self-healing effect and could in turn provide a sustainable irradiation tolerance over the operational lifetime of a reactor.

关键词： L12 nanoparticles High-entropy alloy Helium bubble Phase stability Radiation-induced segregation

Preparation of Ga_2O_3 thin film solar-blind photodetectors based on mixed-phase structure by pulsed laser deposition

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Chinese Physics B 2019年第1期28卷 171-177页

作者： Y M Lu C Li X H Chen S Han P J Cao F Jia Y X Zeng X K Liu w Y Xu w J Liu D L Zhu College of Materials Science and Engineering Shenzhen Key Laboratory of Special Functional MaterialsShenzhen Engineering Laboratory for Advanced Technology of CeramicsGuangdong Research Center for Interfacial Engineering of Functional MaterialsShenzhen UniversityShenzhen 518060China

Gallium oxide(Ga_2O_3) thin films were deposited on a-Al2O3(1120) substrates by pulsed laser deposition(PLD) with different oxygen pressures at 650?C. By reducing the oxygen pressure, mixed-phase Ga_2O_3 films with α and β phases can be obtained, and on the basis of this, mixed-phase Ga_2O_3 thin film solar-blind photodetectors(SBPDs) were *** the responsivities of the mixed-phase Ga_2O_3 SBPDs and the single β-Ga_2O_3 SBPDs at a bias voltage of 25 V,it is found that the former has a maximum responsivity of approximately 12 A/w, which is approximately two orders of magnitude larger than that of the latter. This result shows that the mixed-phase structure of Ga_2O_3 thin films can be used to prepare high-responsivity SBPDs. Moreover, the cause of this phenomenon was investigated, which will provide a feasible way to improve the responsivity of Ga_2O_3 thin film SBPDs.

关键词： Ga2O3 mixed-phase solar-blind photodetector pulsed laser deposition

Synchronous occurrence of gastrointestinal stromal tumors and other primary gastrointestinal neoplasms

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world Journal of Gastroenterology 2006年第33期12卷 5360-5362页

作者： Marek wronski Bogna Ziarkiewicz-wroblewska Barbara Gornicka wlodzimierz Cebulski Maciej Slodkowski Aleksander wasiutynski Ireneusz w Krasnodebski Department of General andGastroenterological Surgery and Nutrition Warsaw University of Medicine ul. Banacha 1A 02-097 Warsaw Poland Department of Pathology WarsawUniversity of Medicine ul. Pawinskiego 7 02-106 Warsaw Poland

AIM： To review clinical and pathologic features of Gastrointestinal strornal tumors （GISTs） occurring synchronously with other primary gastrointestinal neoplasms. METHODS： 28 patients with primary GIST were treated at our institution between 1989 and 2005. Clinical and pathologic records were reviewed. RESULTS： The gastrointestinal stromal tumor occurred simultaneously with other primary GI malignancies in 14% of all patients with GIST. The synchronous stromal tumors were located in the stomach and were incidentally found during the operation. The coexistent neoplasms were colon adenocarcinoma, gastric cancer （2 cases） and gastric lymphoma. CONCLUSION： The synchronous occurrence of GISTs and other gastrointestinal malignancies is more common than it has been considered. The development of gastrointestinal stromal tumors and other neoplasms may involve the same carcinogenic agents.

关键词： Gastrointestinal stromal tumors Synchronousneoplasms