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Microstructure,mechanical properties and dry wear resistance of β-type Ti-15Mo-xNb alloys for biomedical applications 被引量:7
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作者 徐丽娟 肖树龙 +1 位作者 田竟 陈玉勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期692-698,共7页
In order to study the effect of element Nb on the microstructure and properties of the biomedical β-type Ti-Mo based alloys,Ti-15Mo-xNb(x=5,10,15 and 20 in %) alloys were investigated.The dry wear resistance of β-... In order to study the effect of element Nb on the microstructure and properties of the biomedical β-type Ti-Mo based alloys,Ti-15Mo-xNb(x=5,10,15 and 20 in %) alloys were investigated.The dry wear resistance of β-type Ti-15Mo-xNb alloys against Gr15 ball was investigated on CJS111A ball-disk wear instrument.Experimental results indicate that crystal structure and morphology of the Ti-15Mo-xNb alloys are sensitive to their Nb contents.Ti-15Mo-xNb alloys match those for β phase peaks and no any phases are found.The Vickers hardness values of all the Ti-15Mo-xNb alloys are higher than HV200.The compression yield strength of the Ti-15Mo-5Nb alloy is the lowest and that of the Ti-15Mo-10Nb alloy is the highest.For all the Ti-15Mo-xNb alloys,the friction coefficient is not constant but takes a higher value.In dry condition,SEM study reveals deep parallel scars on the wear surfaces of all the Ti-15Mo-xNb alloys under different loads.The friction coefficient of the Ti-15Mo-5Nb alloy under 1 N is the lowest.The wear principal mechanism for Ti-15Mo-xNb alloys is adhesive wear. 展开更多
关键词 β-type Ti-Mo-Nb alloys wear resistance adhesive wear MICROSTRUCTURE mechanical properties
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Kinetic Studies on Forming Iso-nuclear β-type Chelates of Rare Earths with p-Sulphoaminobromophosphonazo
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作者 Fei ZHA Li YUAN +1 位作者 Jin Zhang GAO Hui CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第12期1101-1102,共2页
The kinetic behavior of forming the iso-nuclear β-type chelates of rare earth ions (RE~3+) with p-sulphoaminobromophosphonazo (BPA-pSN) in ClCH2COOH-CH3COONa buffer solutions were studied by a spectrophotometric method.
关键词 β-type chelates rare earths p-sulphoaminobromophosphonazo.\
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Mechanism of Hetero-nuclear β-type Chelates Formed by Rare Earths with p-sulphoaminobromophosphonazo
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作者 袁莉 查飞 +1 位作者 高锦章 陈慧 《Rare Metals》 SCIE EI CAS CSCD 2000年第4期269-274,共6页
The reaction behavior of forming the hetero-nuclear β-type chelates of rare earth ions (RE 3+) with p-sulphoaminobromophosphonazo(BPA-pSN) in ClCH_2COOH-CH_3COONa buffer solutions were studied by a spectrophotometri... The reaction behavior of forming the hetero-nuclear β-type chelates of rare earth ions (RE 3+) with p-sulphoaminobromophosphonazo(BPA-pSN) in ClCH_2COOH-CH_3COONa buffer solutions were studied by a spectrophotometric method. The interaction of RE 3+ with BPA-pSN, which can forms hetero-nuclear β-type chelates having composition ratio of RE_1 (light rare earth):BPA-pSN:RE_2(heavy rare earth ion)=1∶3∶1, is a first-order reaction. Meanwhile, BPA-pSN can only forms homo-nuclear β-type chelates with heavy rare earth ions, having a composition ratio of RE∶BPA-pSN=1∶2 and being a second-order reaction. The rate constants of forming homo-and hetero-nuclear β-type chelates were obtained and the mechanism of forming hetero-nuclear β-type chelates was proposed. 展开更多
关键词 Rate constant Reaction mechanism Hetero-nuclear β-type chelates
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Phase selection-oriented mechanical properties tailoring forβ-type TiNbZrTaSi alloy fabricated by laser powder bed fusion
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作者 Xuan Luo Tao Song +6 位作者 Feng Wang Haizhou Lu Limei Kang Hongwei Ma Dongdong Li Annett Gebert Chao Yang 《Advanced Powder Materials》 2023年第3期77-87,共11页
The morphology and distribution of silicides inα/αþβtype titanium alloys impress on their properties.Nevertheless,the types of silicide precipitates and their formation mechanisms remain unclear inβ-type Ti... The morphology and distribution of silicides inα/αþβtype titanium alloys impress on their properties.Nevertheless,the types of silicide precipitates and their formation mechanisms remain unclear inβ-type Ti–Nb–Zr–Ta alloys.In this study,we report the precipitation behavior of silicides formed upon aging treatment of a laser powder bed fusion(LPBF)-fabricatedβ-type Ti–34.5Nb–6.9Zr–4.9Ta–1.4Si(wt%,TNZTS)alloy.We further discuss their underlying formation mechanism and silicide selection-oriented mechanical properties tailoring for LPBF-fabricated TNZTS alloy.Two novel silicide precipitates were formed:a supersaturated Si–richβ–Ti matrix in the form of a network that can further transform into the(Ti,Zr)2Si(S2)phase with the increase of aging temperature;and a short,rod-like S2 precipitate adjacent to pre-existing dot-shaped S2.The former results from the aggregation of Si solute atoms towards to the dislocation walls/microbands and the subsequent precipitation reaction,while the latter arises from the considerable micro-strain around the phase boundary between the dotshaped S2 andβ-Ti owing to the large difference in their thermal expansion coefficients.The aging-treated TNZTS alloy exhibits a good combination of tensile strength(10835 MPa)and fracture strain(5.6%1.0%),which is attributed to precipitation strengthening,grain-boundary strengthening,and discontinuous intergranular silicide derived from phase selection.The obtained results provide a basis for the design and fabrication of biomedical Sicontainingβ-type Ti alloys with excellent mechanical properties. 展开更多
关键词 Laser powder bed fusion β-type titanium alloys Silicide precipitates Microstructure Mechanical propertie
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Direct evidence for competition between metastable ω and equilibrium α phases in aged β-type Ti alloys 被引量:1
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作者 Shun Guo Qing-Kun Meng +1 位作者 Hong-Ping Li Xin-Qing Zhao 《Rare Metals》 SCIE EI CAS CSCD 2014年第4期390-393,共4页
Precipitation response of a recently developed β-type Ti-25Nb-2Mo-4Sn alloy (wt%) during aging was investigated in detail. Experimental results indicate that the metastable co or equilibrium α phase can form alter... Precipitation response of a recently developed β-type Ti-25Nb-2Mo-4Sn alloy (wt%) during aging was investigated in detail. Experimental results indicate that the metastable co or equilibrium α phase can form alternatively even under the same aging condition, depending on the condition prior to the aging, i.e., solution treatment or severe cold rolling. This provides, for the first time, the direct evidence for the competition between ω and α in aged β-type Ti alloys. This peculiar aging response is found to be closely related to high-density dislocations and grain boundaries which suppress the formation of ω but favor the precipitation of fine α phase. 展开更多
关键词 β-type Ti alloy Phase competition o~ Phase at Phase
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Effect of Pre-cold Rolling-Induced Twins and Subsequent Precipitated x-Phase on Mechanical Properties in a β-Type Ti–Mo Alloy 被引量:3
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作者 Li Xiang Xiao-Hua Min +3 位作者 Xin Ji Satoshi Emura Cong-Qian Cheng Koichi Tsuchiya 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2018年第6期604-614,共11页
This paper reported an effectiveness of pre-cold rolling-induced{332}/113[twins combined with subsequent isothermal x-phase formation for enhancement of uniform elongation in a b-type Ti–15Mo alloy with high yield s... This paper reported an effectiveness of pre-cold rolling-induced{332}/113[twins combined with subsequent isothermal x-phase formation for enhancement of uniform elongation in a b-type Ti–15Mo alloy with high yield strength level.Mechanical{332}/113[twins were induced by cold rolling with an thickness reduction of 5%,which had little effect on x-phase precipitation after aging at 573 K for 3.6 ks.Twinning after the cold rolling was further activated during tensile deformation,even with the presence of isothermal x-phase.This combination of twins and x-phase enhanced uniform elongation from 0 to 9%at yield strength level of 890 MPa.The high yield strength was mainly dominated by dislocation slip due to the isothermal x-phase formation,and early onset of plastic instability after yielding was hindered due to the pre-cold rolling-induced twins.Dynamic microstructural refinement was induced by further twinning activation during deformation,which resulted in high work hardening rate corresponding enhancement of uniform elongation. 展开更多
关键词 β-type titanium alloy Pre-cold rolling Twinning deformation Isothermal x-phase Strength-ductility
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血管紧张素Ⅱ对大鼠骨髓间充质干细胞棕色脂肪变的抑制作用
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作者 刘晨洋 王瑾 +4 位作者 张文婷 王丽清 尹晓晓 赵俊楠 焦向英 《中国组织工程研究》 CAS 北大核心 2025年第23期4859-4867,共9页
背景:骨髓间充质干细胞是脂肪细胞的来源之一,且表达所有肾素血管紧张素系统成分,但血清血管紧张素Ⅱ对骨髓间充质干细胞向棕色脂肪组织分化的影响尚不清楚。目的:观察血管紧张素Ⅱ对骨髓间充质干细胞向棕色脂肪细胞分化的影响,并探究... 背景:骨髓间充质干细胞是脂肪细胞的来源之一,且表达所有肾素血管紧张素系统成分,但血清血管紧张素Ⅱ对骨髓间充质干细胞向棕色脂肪组织分化的影响尚不清楚。目的:观察血管紧张素Ⅱ对骨髓间充质干细胞向棕色脂肪细胞分化的影响,并探究血管紧张素1a型受体敲除对血管紧张素Ⅱ影响骨髓间充质干细胞向棕色脂肪细胞分化的作用及可能机制。方法:分离培养野生型SD大鼠及血管紧张素1a型受体敲除SD大鼠的骨髓间充质干细胞,将其培养至第3代,随机分为4组:野生组,基因敲除组,野生+血管紧张素Ⅱ组,基因敲除+血管紧张素Ⅱ组,在棕色脂肪诱导分化培养基中诱导分化14 d,后2组在每次更换分化培养基的同时加入100 nmol/L血管紧张素Ⅱ进行干预。采用Western blot、qRT-PCR、免疫荧光等方法检测棕色脂肪诱导分化、脂肪分解、β氧化和线粒体生物发生等相关标记物的表达。结果与结论:血管紧张素Ⅱ可抑制骨髓间充质干细胞向棕色脂肪细胞分化,敲除血管紧张素1a型受体基因能够通过促进脂肪分解、增强脂肪酸β氧化、促进线粒体生物发生、增强线粒体功能来改善血管紧张素Ⅱ对骨髓间充质干细胞向棕色脂肪细胞分化的抑制作用。这些发现为肥胖治疗提供了新的研究方向和潜在治疗靶点,揭示了肾素血管紧张素系统在脂肪代谢中的重要作用及其作为治疗目标的潜力。 展开更多
关键词 血管紧张素Ⅱ 骨髓间充质干细胞 棕色脂肪变 线粒体 β氧化 血管紧张素Ⅱ1a受体
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总维生素D、总Ⅰ型胶原氨基端延长肽、β-胶原特殊序列在多发性骨髓瘤中的作用
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作者 王美娥 苏婷 +4 位作者 郭熙哲 黄荣富 郑瑜瑜 陈根旺 范春梅 《中国实验血液学杂志》 北大核心 2025年第1期163-167,共5页
目的:分析总维生素D(tVD)、总Ⅰ型胶原氨基端延长肽(tPINP)、β-胶原特殊序列(β-CTx)在多发性骨髓瘤(MM)分期以及患者预后中的意义。方法:选取2020年至2022年福建医科大学附属第二医院收治的初诊MM患者54例作为观察组(MM组),本院健康... 目的:分析总维生素D(tVD)、总Ⅰ型胶原氨基端延长肽(tPINP)、β-胶原特殊序列(β-CTx)在多发性骨髓瘤(MM)分期以及患者预后中的意义。方法:选取2020年至2022年福建医科大学附属第二医院收治的初诊MM患者54例作为观察组(MM组),本院健康体检人员50例作为对照组。用化学发光法检测两组tVD、tPINP、β-CTx的表达水平;分析不同ISS分期的MM患者tVD、tPINP、β-CTx表达水平的差异;比较不同血红蛋白(Hb)、血钙(Ca)、肌酐(Crea)、白蛋白(ALB)、β2-微球蛋白(β2-MG)、乳酸脱氢酶(LDH)水平的MM患者的tVD、tPINP、β-CTx表达水平,并分别将tVD、tPINP、β-CTx表达水平与各临床参数进行相关性分析;分析tVD、tPINP、β-CTx表达水平与MM患者无进展生存期(PFS)的关系。结果:MM组tVD表达水平为21.73±14.45 ng/ml,明显低于对照组的30.78±9.94 ng/ml(P=0.022);MM组的β-CTx的表达水平为1.43±0.99 ng/ml,明显高于对照组的0.53±0.29 ng/ml(P=0.013)。ISS分期在Ⅰ-Ⅱ期的MM患者tVD水平为29.50±14.59 ng/ml,明显高于Ⅲ期MM患者的12.62±7.73ng/ml(P=0.028),表明分期越高,tVD水平越低。高Ca水平(>2.65 mmol/L)的MM患者的tPINP、β-CTx均明显高于低Ca水平(≤2.65 mmol/L)患者(P=0.016,P=0.021)。MM患者的tVD水平与ALB水平呈正相关(r=0.570),tPINP水平与Ca、β2-MG水平呈正相关(r=0.791,r=0.673),β-CTx水平与tPINP水平呈正相关(r=0.616)。tVD低表达组的PFS明显低于tVD高表达组(P=0.041)。结论:tVD在MM中表达水平降低,其可作为评估疾病分期、预后的指标;β-CTx在MM中表达水平增高;tPINP、β-CTx可能与MM患者的溶骨性表现、肾功能改变等临床症状存在相关性。 展开更多
关键词 总维生素D 总Ⅰ型胶原氨基端延长肽 β-胶原特殊序列 多发性骨髓瘤
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Design, Manufacture and Measurements of Beta-Type Stirling Engine with Rhombic Drive Mechanism
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作者 Mohammed Yunus Mohammad S. Alsoufi Anil Kumar Rathod 《Modern Mechanical Engineering》 2016年第4期113-128,共17页
The purpose of carrying out present work is to design, build and test a rhombic drive Stirling engine with a β-type configuration consisting of two dynamic pistons (displacer and power) reciprocates in the in-line co... The purpose of carrying out present work is to design, build and test a rhombic drive Stirling engine with a β-type configuration consisting of two dynamic pistons (displacer and power) reciprocates in the in-line concentric cylinder arrangement. The displacement rod is assembled concentrically inside the power piston rod. The rhombic drive mechanism is proposed in such a way that, by using a pair of gear wheels the sliding motion of both piston rods is controlled and thus, an engine is balanced. The developed prototype has a swept volume of 75 cm<sup>3</sup> with the displacer piston and power piston cylinder hot ends heated by liquefied petroleum gas (LPG) burner and cooled water, respectively. It uses air as the working gas at atmospheric pressure for initial charging of the engine. Several designs were studied before settling on a β-type configuration. The LPG gas burner was considered as a potential heat source. The various elements of an engine (heater, cooler, re-generator, flywheel and piping systems) were designed, constructed and analyzed. The testing results revealed that the engine at initial atmospheric air filling started working in only about 120 seconds at an LPG heater temperature of 400℃ (824<sup>&deg;</sup>F) with 280 rpm. At a heater temperature of 550℃ (1022<sup>&deg;</sup>F), the engine speed was 630 rpm. At the engine speed of 245 rpm, the maximum torque was 0.215 Nm, while the maximum power was 8 Watts at 355 rpm. Engine speed increased with the increase of flame temperature. Several tests were performed on the engine to improve its running efficiency and critical problem areas were isolated and addressed. Moreover, results revealed that Stirling engines working with relatively low-temperature air are potentially attractive engines of the future, especially LPG powered low temperature differential Stirling engines. The Stirling engine was capable of generating between 50 to 100 Watts of electricity. 展开更多
关键词 Stirling Engine Engine Performance Rhombic Driving Mechanisms β-type
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β相氧化镓p型导电研究进展
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作者 查显弧 万玉喜 张道华 《人工晶体学报》 北大核心 2025年第2期177-189,共13页
β相氧化镓(β-Ga_(2)O_(3))具有超宽带隙、高击穿电场和容易制备等优势,是功率器件的理想半导体材料。但由于β-Ga_(2)O_(3)价带顶能级位置低、能带色散关系平坦,其p型掺杂目前仍具有挑战性,限制了p-n结及双极性晶体管的开发。利用尺... β相氧化镓(β-Ga_(2)O_(3))具有超宽带隙、高击穿电场和容易制备等优势,是功率器件的理想半导体材料。但由于β-Ga_(2)O_(3)价带顶能级位置低、能带色散关系平坦,其p型掺杂目前仍具有挑战性,限制了p-n结及双极性晶体管的开发。利用尺寸效应、缺陷调控、非平衡动力学及固溶提升价带顶能级等方案是目前实现β-Ga_(2)O_(3)p型掺杂的主要策略。对于β-Ga_(2)O_(3)p-n同质结和异质结,提高晶体质量、减少界面缺陷态是优化器件性能的关键问题。本文针对β-Ga_(2)O_(3)的p型导电问题,系统阐述了β-Ga_(2)O_(3)电子结构,实验表征及理论计算掺杂能级方法,p型掺杂困难原因,以及改进p型掺杂的突破性研究进展。最后简单介绍了β-Ga_(2)O_(3)p-n同质结和异质结器件的相关工作。利用复合缺陷调控、非平衡动力学、固溶等方案,以及不同方案的协同实现体相β-Ga_(2)O_(3)的p型掺杂仍需要深入探索,p-n同质及异质结的器件性能需要进一步优化。 展开更多
关键词 β-Ga_(2)O_(3) p型导电 电子结构 受主能级 固溶 P-N结
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Deep oxidative desulfurization of gas oil based on sandwich-type polysilicotungstate supported β-cyclodextrin composite as an efficient heterogeneous catalyst 被引量:4
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作者 Mohammad Ali Rezvani Sahar Khandan +1 位作者 Negin Sabahi Hamid Saeidian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第10期2418-2426,共9页
In this work,in order to obtain deep clean gas oil,a novel organic–inorganic hybrid(n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin(abbreviated as TBA-Si WCd@β-CD)composite was synthesized by supporting quaternary ammoniu... In this work,in order to obtain deep clean gas oil,a novel organic–inorganic hybrid(n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin(abbreviated as TBA-Si WCd@β-CD)composite was synthesized by supporting quaternary ammonium salt of sandwich-type polysilicotungstate onβ-cyclodextrin(TBA-SiWCd@β-CD)as an efficient catalyst for oxidative desulfurization(ODS)of gas oil.The successful composition of the materials explained by the formation of host–vip inclusion complex,which confirmed through FTIR,UV–vis,XRD,SEM,and EDX characterization analyses.Experimental results revealed that the levels of sulfur content and mercaptan compounds of gas oil lowered with 97%removal efficiency.Compared with the ODS treatment of gas oil,the TBA-Si WCd@β-CD composite showed an outstanding catalytic performance for the oxidation of dibenzothiophene(DBT)in the prepared model fuel.The main factors that influence the desulfurization efficiency and the kinetic study of the ODS process were investigated.The prepared heterogeneous catalyst was found to give remarkable reusability for five runs without a discernible decrease in its activity.This study suggested the potential application of the TBA-Si WCd@β-CD catalyst for removal of hazardous sulfur compounds from gas oil fuel. 展开更多
关键词 OXIDATIVE DESULFURIZATION SANDWICH-type POLYOXOMETALATE Β-CYCLODEXTRIN Heterogeneous catalyst
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Highly efficient synthesis of β-amino esters via Mannich-type reaction under solvent-free conditions using ZnCl_2 catalyst 被引量:8
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作者 Albert S.C.Chan 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期407-410,共4页
β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid de... β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid derivatives. 展开更多
关键词 β-Amino esters Aspartic acid derivativates Mannich-type reaction SOLVENT-FREE Krapcho decarboxylation reaction Zinc chloride
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2型糖尿病周围神经病变与胰岛β细胞功能的相关性研究 被引量:1
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作者 蒋飞霞 黄炫赓 +5 位作者 黄济华 张薇 李郭乔 宁候发 余博先 苏宏业 《中国现代医生》 2024年第7期17-20,共4页
目的探讨2型糖尿病周围神经病变与胰岛β细胞功能的相关性。方法选取2020年1月至12月广西医科大学第二附属医院收治的298例2型糖尿病患者为研究对象,根据是否合并周围神经病变将其分为周围神经病变组(n=178)和无周围神经病变组(n=120)... 目的探讨2型糖尿病周围神经病变与胰岛β细胞功能的相关性。方法选取2020年1月至12月广西医科大学第二附属医院收治的298例2型糖尿病患者为研究对象,根据是否合并周围神经病变将其分为周围神经病变组(n=178)和无周围神经病变组(n=120)。采用二两馒头餐后30min净增C肽与葡萄糖比值(ΔC肽30/ΔG30)和30min净增胰岛素与葡萄糖比值(Δ胰岛素30/ΔG30)评估早期阶段胰岛分泌功能;采用二两馒头餐后120min血糖曲线下面积(area under the curve,AUC)校正后的C肽和胰岛素AUC(C肽_(AUC)/G_(AUC)、胰岛素_(AUC)/G_(AUC))评估总的β细胞分泌功能。多因素Logistic回归分析探讨2型糖尿病并发周围神经病变的危险因素。结果周围神经病变组患者的餐后60min C肽、120min C肽、ΔC肽30/ΔG30、C肽_(AUC)/G_(AUC)均显著低于无周围神经病变组(P<0.05)。ΔC肽30/ΔG30和C肽_(AUC)/G_(AUC)与高密度脂蛋白胆固醇、空腹血糖、餐后2h血糖、糖化血红蛋白均呈负相关,与体质量指数、尿酸均呈正相关(P<0.05)。多因素Logistic回归分析结果显示,空腹血糖升高、C肽_(AUC)/G_(AUC)降低均是糖尿病患者发生周围神经病变的独立危险因素(P<0.05)。结论2型糖尿病患者胰岛β细胞功能下降是糖尿病周围神经病变发病的独立危险因素,应积极保护胰岛β细胞功能以延缓周围神经病变的发生。 展开更多
关键词 2型糖尿病 Β细胞功能 周围神经病变
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基线胰岛β细胞功能与短期胰岛素治疗后2型糖尿病疾病缓解的关系
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作者 叶菁 季美霞 曾志复 《中国药物与临床》 CAS 2024年第16期1038-1042,共5页
目的分析基线胰岛β细胞功能与短期胰岛素治疗后2型糖尿病疾病缓解的关系。方法选取2021年1月至2023年12月于浙江省丽水市人民医院建档并行短期胰岛素治疗的2型糖尿病患者150例,收集基线临床指标、胰岛素抵抗稳态模型(homeostasis model... 目的分析基线胰岛β细胞功能与短期胰岛素治疗后2型糖尿病疾病缓解的关系。方法选取2021年1月至2023年12月于浙江省丽水市人民医院建档并行短期胰岛素治疗的2型糖尿病患者150例,收集基线临床指标、胰岛素抵抗稳态模型(homeostasis model assessment of insulin resistance,HOMA-IR)、胰岛β细胞功能指数(homeostasis model assessment-β,HOMA-β)、胰岛素分泌敏感性指数-2(insulin secretion sensitivity index-2,ISSI-2)以及修正的胰岛β细胞功能指数(modifiedβ-cell function index,MBCI),按照停药后观察期内的糖尿病缓解情况分为缓解组(52例)与未缓解组(93例)。比较缓解组与未缓解组临床资料,采用多因素二元Logistic回归模型分析基线β细胞功能与短期胰岛素治疗后2型糖尿病疾病缓解的关系。结果将不符合要求的5例患者剔除后最终纳入研究患者145例。未缓解组年龄中位数50.09岁,缓解组40.83岁,基线空腹血糖水平(6.4±1.4)mmol/L、HbA1c水平(6.9±0.8)%比缓解组的(5.3±1.2)mmol/L、(6.1±0.5)%更高,HOMA-β中位数37.80、ISSI-2中位数149.24以及MBCI中位数22.94较缓解组(50.14、278.21、32.80)低,病程较缓解组长,差异有统计学意义(t/Z=-10.301、-4.974、-6.884、27.037、30.702、13.914、-4.803,P<0.05)。多因素分析结果发现,HOMA-β、ISSI-2以及MBCI均为疾病缓解的保护因素(OR=0.903、0.871、0.857,P<0.05)。结论基线胰岛β细胞功能是短期胰岛素治疗后2型糖尿病疾病缓解的主要病理生理学因素,基线胰岛β细胞功能越好疾病得到缓解的可能性也越大。 展开更多
关键词 Β细胞功能 胰岛素 糖尿病 2型 治疗
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恩格列净与利拉鲁肽联合治疗肥胖/超重2型糖尿病患者的疗效及其对炎症因子的影响:一项前瞻、随机、开放、平行对照的临床研究
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作者 王静 李彩格 +4 位作者 王婷 刘子渤 盖斌 金杨瑜 张力辉 《临床荟萃》 CAS 2024年第10期909-914,共6页
目的探讨恩格列净与利拉鲁肽联合治疗肥胖/超重2型糖尿病(T2DM)患者的临床疗效及其对炎症因子和胰岛功能的影响。方法选取2021年6月-2023年9月在河北医科大学第二医院住院治疗的肥胖/超重T2DM患者58例。采用随机数表法将受试者随机分为... 目的探讨恩格列净与利拉鲁肽联合治疗肥胖/超重2型糖尿病(T2DM)患者的临床疗效及其对炎症因子和胰岛功能的影响。方法选取2021年6月-2023年9月在河北医科大学第二医院住院治疗的肥胖/超重T2DM患者58例。采用随机数表法将受试者随机分为:试验组(Lira+Empa组)和对照组(Lira组),各29例。试验组接受恩格列净+利拉鲁肽联合治疗,对照组仅接受利拉鲁肽治疗,比较两组治疗前、后糖代谢指标、脂代谢指标、炎症因子、胰岛功能指标及不良反应。结果治疗后,两组空腹血糖(FPG)、餐后2 h血糖(2 hPPG)、糖化白蛋白(GA)、总胆固醇、甘油三酯、低密度脂蛋白胆固醇、体重指数(BMI)、白细胞介素(IL)-6、IL-10水平明显低于治疗前,Lira+Empa组FPG、2 hPPG、GA、BMI、IL-6、IL-10水平均低于Lira组,差异有统计学意义(P<0.05)。治疗后,两组C肽、空腹胰岛素和稳态胰岛素分泌指数(HOMA-β)均较治疗前升高,其中,Lira+Empa组HOMA-β明显高于Lira组,差异有统计学意义(P<0.05)。两组不良反应发生率无明显差异。结论相较于利拉鲁肽单药治疗,恩格列净+利拉鲁肽联合治疗能进一步提高T2DM降糖疗效,明显改善患者血糖水平和胰岛功能,并有效降低体重,对炎症因子水平有改善作用,且安全性良好。 展开更多
关键词 糖尿病 2型 恩格列净 利拉鲁肽 炎症因子 稳态胰岛素分泌指数
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基于TGF-β_(1)/Smad信号通路探究度拉糖肽对2型糖尿病肾病大鼠肾损伤的影响及机制
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作者 孔五宝 王晓蕴 +3 位作者 牛跃龙 陈伟 常珊珊 邢立勇 《河北医学》 CAS 2024年第11期1815-1820,共6页
目的:探讨基于转化生长因子-β(TGF-β_(1))/Smad信号通路度拉糖肽(Dula)对2型糖尿病肾病(T2DN)大鼠肾损伤的影响。方法:随机选取10只大鼠作为Control组,其余大鼠构建T2DN模型,将建模成功的大鼠随机分为T2DN组、L-Dula、M-Dula、H-Dula,... 目的:探讨基于转化生长因子-β(TGF-β_(1))/Smad信号通路度拉糖肽(Dula)对2型糖尿病肾病(T2DN)大鼠肾损伤的影响。方法:随机选取10只大鼠作为Control组,其余大鼠构建T2DN模型,将建模成功的大鼠随机分为T2DN组、L-Dula、M-Dula、H-Dula,Dula+SRI-011381每组10只。测定各组大鼠体质量;采用全自动生化分析仪检测T2DN大鼠血清中ALB、Scr、BUN、TG、TC含量;HE和PAS染色观察T2DN大鼠肾组织病理改变;Western blot检测T2DN大鼠肾组织中TGF-β_(1)、Smad2/3、Smad7蛋白的表达。结果:T2DN组肾小球肥大,基底膜增厚,囊腔萎缩,间质炎性细胞浸润,肾小球内糖原沉积增多,可见红色染色区域,24h尿蛋白、Scr、BUN、FBG、TG、TC、TGF-β_(1)、Smad2/3表达高于Control组,体质量、Smad7表达低于Control组(P<0.05);L-Dula、M-Dula、H-Dula组肾小球和肾小管病变程度均依次减轻,红色染色区域依次减少,24h尿蛋白、Scr、BUN、FBG、TG、TC、TGF-β_(1)、Smad2/3表达低于T2DN组,体质量、Smad7表达高于T2DN组(P<0.05);Dula+SRI-011381组肾小球和肾小管病变加重、红色染色区域增大、24h尿蛋白、Scr、BUN、FBG、TG、TC、TGF-β_(1)、Smad2/3表达高于H-Dula组,体质量、Smad7表达低于H-Dula组(P<0.05)。结论:Dula可能通过抑制TGF-β_(1)/Smad信号通路抑制T2DN大鼠肾损伤。 展开更多
关键词 2型糖尿病 转化生长因子-β SMAD 度拉糖肽 肾损伤
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β型Ti-15Mo合金中α相变体选择
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作者 任诚 闵小华 费琪 《金属热处理》 CAS CSCD 北大核心 2024年第9期1-10,共10页
利用SEM、EBSD等方法研究了固溶时效后Ti-15Mo合金中β基体和晶界处析出α相的变体选择行为。结果表明,固溶态试样由无择优取向的单一β晶粒构成。固溶时效态试样中晶内α相不发生变体选择,但晶内α相变体之间存在自协调现象,并导致各... 利用SEM、EBSD等方法研究了固溶时效后Ti-15Mo合金中β基体和晶界处析出α相的变体选择行为。结果表明,固溶态试样由无择优取向的单一β晶粒构成。固溶时效态试样中晶内α相不发生变体选择,但晶内α相变体之间存在自协调现象,并导致各α相变体呈现60°交叉状分布。膜状晶界α相的变体选择受到相邻β晶粒间取向差的影响,取向差较小时会与两侧的β晶粒均保持Burgers取向关系,而取向差较大时会受到界面取向的影响。晶界魏氏组织的变体选择取决于形核位置,形核于膜状晶界α相的魏氏组织选择与晶界α相相同的变体,形核于膜状晶界α相与β基体界面处的魏氏组织同时受到两者的共同影响。 展开更多
关键词 Β型钛合金 时效处理 等温α相 变体选择
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不同变形方式β型Ti-Mo-Fe合金的低周疲劳性能
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作者 李纵纵 闵小华 +1 位作者 毛永换 姚凯 《材料工程》 EI CAS CSCD 北大核心 2024年第8期130-141,共12页
利用OM,SEM,EBSD和电液伺服疲劳试验机等研究不同塑性变形方式的Ti-10Mo-xFe(x=1,2,3,质量分数/%)合金的低周疲劳性能,分析总应变幅(Δε_(t)/2=0.5%,1.0%和1.5%)和Fe含量对合金力学响应、组织结构和疲劳裂纹扩展行为的影响。结果表明:... 利用OM,SEM,EBSD和电液伺服疲劳试验机等研究不同塑性变形方式的Ti-10Mo-xFe(x=1,2,3,质量分数/%)合金的低周疲劳性能,分析总应变幅(Δε_(t)/2=0.5%,1.0%和1.5%)和Fe含量对合金力学响应、组织结构和疲劳裂纹扩展行为的影响。结果表明:随着应变幅和Fe含量的增加,合金的低周疲劳性能下降。各合金的循环应力响应行为普遍表现为初始循环硬化,随后趋于循环稳定或轻微的循环软化,直至断裂失效。Ti-10Mo-1Fe合金的塑性变形由{332}〈113〉孪生主导,随着Fe含量的增加,合金的塑性变形方式向位错滑移转变。低应变幅下Ti-10Mo-1Fe合金疲劳源区孪晶数量较少,沿裂纹扩展方向孪晶数量逐渐增加;高应变幅下近断口区域出现大量孪晶。Ti-10Mo-1Fe合金中孪晶的大量产生及交割将晶粒内部分割成网状组织,从而起到细化晶粒的作用,有效释放应力集中并延缓疲劳裂纹的萌生。同时微裂纹扩展至孪晶界附近时发生裂纹偏折,合金中大量的孪晶界有效延长疲劳裂纹扩展路径。 展开更多
关键词 Β型钛合金 低周疲劳 孪生诱发塑性效应 {332}〈113〉孪生 位错滑移
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钼含量和均匀化处理冷却方式对β型Ti-Mo合金中点缺陷弛豫的影响
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作者 周正存 朱晓斌 王幸福 《机械工程材料》 CAS CSCD 北大核心 2024年第1期10-15,共6页
采用真空电弧熔炼制备β型Ti-xMo(x为质量分数/%,3~24)合金,并进行950℃×20 min均匀化处理,随后分别水冷和炉冷至室温,通过内耗测试结合物相和微观结构分析,研究了钼含量和冷却方式对该合金点缺陷弛豫的影响。结果表明:炉冷和水冷T... 采用真空电弧熔炼制备β型Ti-xMo(x为质量分数/%,3~24)合金,并进行950℃×20 min均匀化处理,随后分别水冷和炉冷至室温,通过内耗测试结合物相和微观结构分析,研究了钼含量和冷却方式对该合金点缺陷弛豫的影响。结果表明:炉冷和水冷Ti-xMo合金中均出现2个Snoek型驰豫峰,炉冷Ti-xMo合金的弛豫峰随钼含量的变化特征与水冷合金相似。2种冷却方式下Ti-xMo合金在加热时的低温峰峰高随钼含量的增加而增大,但峰温几乎不变,峰高的增大与β相和间隙氧原子含量的增多有关;除Ti-3Mo合金外,其余合金高温峰的峰高和峰温都随钼含量增加而增大,峰高和峰温的增大与钼和氧的相互作用增强有关。 展开更多
关键词 点缺陷弛豫 β型Ti-Mo合金 钼含量 间隙氧原子
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巨型艾美耳球虫Th1类细胞因子刺激性分子EmARM-β对鸡PBMC和T细胞亚群免疫功能的影响 被引量:1
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作者 蒲响林 潘仰栋 +6 位作者 相权珈 孙晓婷 陆明敏 严若峰 徐立新 李祥瑞 宋小凯 《南京农业大学学报》 CAS CSCD 北大核心 2024年第1期9-17,共9页
[目的]本文旨在探讨巨型艾美耳球虫Th1类细胞因子刺激性分子Armadillo/β-catenin样重复序列蛋白(EmARM-β)对鸡免疫细胞功能的影响。[方法]利用密度梯度离心法和免疫磁珠分选法分别分离出鸡外周血单个核细胞(peripheral blood mononucl... [目的]本文旨在探讨巨型艾美耳球虫Th1类细胞因子刺激性分子Armadillo/β-catenin样重复序列蛋白(EmARM-β)对鸡免疫细胞功能的影响。[方法]利用密度梯度离心法和免疫磁珠分选法分别分离出鸡外周血单个核细胞(peripheral blood mononuclear cell,PBMC)、CD8^(+)T细胞和CD4^(+)CD25^(-)T细胞,之后将EmARM-β重组蛋白(rEmARM-β)分别与上述细胞进行体外共孵育6 h,利用CCK-8试剂和qPCR法分别检测并分析其对上述细胞增殖能力及相关细胞因子分泌水平的影响。[结果]经免疫磁珠分选后,流式细胞术检测鸡CD8^(+)T细胞和CD4^(+)CD25^(-)T细胞的纯度分别为93.01%和88.88%。与对照组相比,rEmARM-β显著促进鸡PBMC的增殖能力,显著上调Th1类细胞因子(ifn-γ和il-2)和促炎性细胞因子(il-1β、il-6和il-17a)mRNA水平;显著促进CD8^(+)T细胞的增殖能力,显著上调其ifn-γ、il-2和tnf-α mRNA水平,显著上调穿孔素、fasl(Fas配体)和fas mRNA水平;能显著促进CD4^(+)CD25^(-)T细胞的增殖能力,显著上调其ifn-γ和il-2 mRNA水平,下调il-4和il-10 mRNA水平。[结论]EmARM-β可以有效促进鸡PBMC和T细胞亚群(CD8^(+)T细胞和CD4^(+)CD25^(-)T细胞)的增殖能力,提升其Th1类细胞因子和促炎性细胞因子的分泌水平,提示EmARM-β具有研发鸡球虫病新型疫苗候选抗原的潜力。 展开更多
关键词 巨型艾美耳球虫 Th1类细胞因子刺激性分子 EmARM-β T细胞亚群 免疫功能
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