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The Impact of Matrix Treatment (Family Training) in Reducing the Amount of Drug Consumption in Heroin and Crack Addicts
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作者 Seyyed Hossein Seid Narges Dolatyari 《Health》 2015年第4期419-422,共4页
The purpose of this study is to investigate the impact of family training based on matrix model in reducing the amount of drug consumption by heroin and crack addicts. The subjects were referral to Karaj Clinic, Karaj... The purpose of this study is to investigate the impact of family training based on matrix model in reducing the amount of drug consumption by heroin and crack addicts. The subjects were referral to Karaj Clinic, Karaj City, Iran, for crack abuse in 2013. In order to select participants convenience sampling was been used and totally 45 patients were selected (15 heroin addict, 15 crack addict, and 15 with combination of heroin and crack addiction) and put into two groups of experimental and control groups randomly. For collecting the data, Addiction Severity Index questionnaire was used. Descriptive and inferential statistics were used through one-way analysis of covariance for data analyzing. The results indicated that there was statistical difference between the experimental and control group with consumption of heroin and crack in family status, mental and substance use and also it has been shown that the experimental group with heroine consumption achieved better performance compared with the control group in the amount of consumption. 展开更多
关键词 matrix treatment (Family Training) Drug Consumption HEROIN CRACK
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Model-based interpretation of bottomhole pressure records during matrix treatments in layered formations
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作者 Igor Reznikov Dmitry Abdrazakov Dimitry Chuprakov 《Petroleum Science》 SCIE EI CAS 2024年第5期3587-3611,共25页
During injection treatments, bottomhole pressure measurements may significantly mismatch modeling results. We devise a computationally effective technique for interpretation of fluid injection in a wellbore interval w... During injection treatments, bottomhole pressure measurements may significantly mismatch modeling results. We devise a computationally effective technique for interpretation of fluid injection in a wellbore interval with multiple geological layers based on the bottomhole pressure measurements. The permeability, porosity and compressibility in each layer are initially setup, while the skin factor and partitioning of injected fluids among the zones during the injection are found as a solution of the problem. The problem takes into account Darcy flow and chemical interactions between the injected acids, diverter fluids and reservoir rock typical in modern matrix acidizing treatments. Using the synchronously recorded injection rate and bottomhole pressure, we evaluate skin factor changes in each layer and actual fluid placement into the reservoir during different pumping jobs: matrix acidizing, water control, sand control, scale squeezes and water flooding. The model is validated by comparison with a simulator used in industry. It gives opportunity to estimate efficiency of a matrix treatment job, role of every injection stage, and control fluid delivery to each layer in real time. The presented interpretation technique significantly improves accuracy of matrix treatments analysis by coupling the hydrodynamic model with records of pressure and injection rate during the treatment. 展开更多
关键词 matrix treatment Inverse problem Forward problem Skin factor Interpretation
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Effect of Heat Treatment on Microstructure and Mechanical Properties of Si Cp/2024 Aluminum Matrix Composite 被引量:2
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作者 柳培 王爱琴 +1 位作者 XIE Jingpei HAO Shiming 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第6期1229-1233,共5页
SiCp/2024 aluminum alloy matrix composite was prepared by powder metallurgy method. Effects of heat treatment on the microstructure and mechanical properties of composite were investigated by SEM, EDS, XRD, HREM, tens... SiCp/2024 aluminum alloy matrix composite was prepared by powder metallurgy method. Effects of heat treatment on the microstructure and mechanical properties of composite were investigated by SEM, EDS, XRD, HREM, tensile and hardness tests. The experimental results showed that SiC particles distributed uniformly in the matrix and were in good combination with matrix. The tensile strength and hardness were improved significantly after heat treatment. With the increase of solid solution temperature, the alloy phases dissolved in the matrix gradually. When the solid solution temperature arrived at 505 ℃, the alloy phases dissolved thoroughly, and the composite exhibited the highest tensile strength and hardness(σb=360 MPa, HBS=104). The main strengthening phase was Al2Cu, which was granular and distributed dispersively in the matrix. Effect of T6 was better than that of T4 at the same solid solution temperature. 展开更多
关键词 SiCp/2024 aluminum matrix heat treatment microstructure mechanical properties
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Heat treatment optimization for tensile properties of 8011 Al/15% SiCp metal matrix composite using response surface methodology 被引量:7
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作者 V.VEMBU G.GANESAN 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2015年第4期390-395,共6页
In this study,a mathematical model was developed to optimize the heat treatment process for maximum tensile strength and ductility of aluminum(8011) silicon carbide particulate composites.The process parameters are so... In this study,a mathematical model was developed to optimize the heat treatment process for maximum tensile strength and ductility of aluminum(8011) silicon carbide particulate composites.The process parameters are solutionizing time,aging temperature,and aging time.The experiments were performed on an universal testing machine according to centre rotatable design matrix.A mathematical model was developed with the main and interactive effects of the parameters considered.The analysis of variance technique was used to check the adequacy of the developed model.The optimum parameters were obtained for maximum tensile strength.Fractographic examination shows the cracks and dimples on the fractured surfaces of heat-treated specimen. 展开更多
关键词 热处理工艺优化 颗粒复合材料 响应曲面法 拉伸性能 金属基体 万能试验机 开发模型
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Effect of heat-treatment on microstructure and properties of SiC particulate-reinforced aluminum matrix composite
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作者 孙有平 严红革 +1 位作者 陈振华 张昊 《中国有色金属学会会刊:英文版》 CSCD 2007年第A01期318-321,共4页
The effects of solid solution and aging processing on the microstructures and mechanical properties of the multi-layer spray co-deposited 7090Al/SiCp composite were investigated. The experimented results show that fin... The effects of solid solution and aging processing on the microstructures and mechanical properties of the multi-layer spray co-deposited 7090Al/SiCp composite were investigated. The experimented results show that fine grains and homogeneous microstructures can be obtained,the average grain size of the as-solid solution treated and as-aged composites after extrusion is under 3.0 μm. A large amount of the Cu-rich phase particles form in the as-extruded samples,and solve into the matrix after solid solution treatment. After aging,the size of the precipitate phases,mainly MgZn2 and CuAl2 is less than 1.0 μm,which homogeneously distribute inside the grains and at the grain boundaries. The ultimate tensile strength of the composite treated at T6 state,i.e. solid solution treated at 475 ℃ for 1 h then aged at 120 ℃ for 24 h,is up to 765 MPa. 展开更多
关键词 合金 沉积物 热处理技术
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Verification of the Validity of the NPT Treatment in Hereditary Spastic Paraplegia: An Investigation Performed by Application of Random Matrix Theory
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作者 Elio Conte Ken Ware +2 位作者 Riccardo Marvulli Giancarlo Ianieri Marisa Megna 《World Journal of Neuroscience》 2016年第1期1-17,共17页
We have applied the Random Matrix Theory in order to examine the validity of the NPT treatment in HSP. We have investigated the pathology examining the sEMG recorded signal for about eight minutes. We have performed s... We have applied the Random Matrix Theory in order to examine the validity of the NPT treatment in HSP. We have investigated the pathology examining the sEMG recorded signal for about eight minutes. We have performed standard electromyographic investigations as well as we have applied the RMT method of analysis. We have investigated the sEMG signals before and after the NPT treatment. The application of a so robust method as the RMT evidences that the NPT treatment was able to induce a net improvement of the disease respect to the pathological status before NPT. 展开更多
关键词 Hereditary Spastic Paraplegia NPT treatment Random matrix Theory Surface Electromiography
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Matrix弹簧圈栓塞颅内动脉瘤的随访分析 被引量:3
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作者 庞刚 肖泉 +2 位作者 刘若平 钟书 梁有明 《中国微侵袭神经外科杂志》 CAS 2012年第10期449-451,共3页
目的评价Matrix弹簧圈栓塞颅内动脉瘤的治疗效果和稳定性。方法回顾性分析72例共80个动脉瘤病人的临床资料,均采用Matrix栓塞治疗。根据治疗结果分析栓塞程度、瘤颈宽度、动脉瘤直径、支架辅助与动脉瘤再生长率的关系。结果动脉瘤致密栓... 目的评价Matrix弹簧圈栓塞颅内动脉瘤的治疗效果和稳定性。方法回顾性分析72例共80个动脉瘤病人的临床资料,均采用Matrix栓塞治疗。根据治疗结果分析栓塞程度、瘤颈宽度、动脉瘤直径、支架辅助与动脉瘤再生长率的关系。结果动脉瘤致密栓塞47个(58.8%),瘤颈残留24个(30.0%),瘤体残留9个(11.3%)。手术相关并发症7例(9.7%),死亡2例。64例随访6~48个月,无再出血及新增神经功能缺损。38例42个动脉瘤术后6~24个月接受血管造影随访,动脉瘤稳定26个(61.9%),进一步栓塞5个(11.9%),再生长11个(26.2%);2个(4.8%)瘤体残留者复发需再次治疗。统计学分析显示:动脉瘤栓塞越致密,再生长率越低(P<0.05),术后Raymond分级、动脉瘤大小、瘤颈宽度、体颈比、是否使用支架辅助栓塞与再生长率无明显相关(均P>0.05)。结论随访显示Matrix栓塞颅内动脉瘤安全、有效和稳定,有必要长期随访。 展开更多
关键词 颅内动脉瘤 matrix弹簧圈 血管内治疗 随访研究
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Effect of heat treatments on failure mechanism of SiC_p/2124 Al composite 被引量:1
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作者 M.Murato■ lu 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第4期839-845,共7页
The mechanical response of a 17%(volume fraction) silicon carbide particles reinforced 2124 Al composite prepared by powder metallurgy techniques was studied by altering the matrix strength with different heat treatme... The mechanical response of a 17%(volume fraction) silicon carbide particles reinforced 2124 Al composite prepared by powder metallurgy techniques was studied by altering the matrix strength with different heat treatments. The fracture mechanisms and the deformation microstructure were examined by scanning electron microscopy. The results show that matrix strength appears to play an important role in influcing the behaviour of the composite under hardness and tensile loading conditions and also fracture mechanisms.The high matrix strength results in a larger decrease in yield strength due to the increasing damage probability. The tensile yield strength values decrease under peak aged and overaged condition whereas under the solutinized condition the opposite effect can be seen. 展开更多
关键词 有色金属 热处理 表面裂纹 微结构
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Processing and mechanical properties of 2024 aluminum matrix composites containing Tungsten and Tantalum prepared by PM 被引量:4
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作者 LIAN Youyun YANG Zhimin YANG Jian MAO Changhui 《Rare Metals》 SCIE EI CAS CSCD 2006年第z2期136-140,共5页
The 2024 Al composites containing W, Ta were fabricated by powder metallurgy for their potential use as shielding material. W, Ta powders and gas-atomized 2024 Al aluminum powders were mixed by a ball mixer. The mixtu... The 2024 Al composites containing W, Ta were fabricated by powder metallurgy for their potential use as shielding material. W, Ta powders and gas-atomized 2024 Al aluminum powders were mixed by a ball mixer. The mixtures were consolidated by cold isostatic pressing (CIP) and then hot-extruded into full-density bars. The extruded bars were heat treated in T6 conditions. The microstructure and its relationship with the mechanical properties were investigated by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results show that the particles of nonuniform size and irregular shape randomly disperse in the 2024 aluminum alloy matrix. The tensile tests show that an increase of tensile strength and decrease of elongation to failure of the heat treated composites compared with the extruded composites. 展开更多
关键词 2024 Al matrix composites powder metallurgy hot extrusion heat treatment
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热处理对GNP-Al复合材料显微组织和性能的影响
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作者 简正豪 邹金红 +2 位作者 陈佳 赵英 曾敏 《轻金属》 2024年第6期39-44,共6页
本文以石墨烯为增强相,采用高能超声辅助铸造法及后续热处理制备了铝基复合材料,并研究石墨烯和热处理对复合材料显微组织、力学性能和耐磨性能的影响。结果表明,石墨烯促进了复合材料晶粒细化,且热处理后Si相进一步细化及圆整。经热处... 本文以石墨烯为增强相,采用高能超声辅助铸造法及后续热处理制备了铝基复合材料,并研究石墨烯和热处理对复合材料显微组织、力学性能和耐磨性能的影响。结果表明,石墨烯促进了复合材料晶粒细化,且热处理后Si相进一步细化及圆整。经热处理后复合材料的屈服强度和抗拉强度(245和319MPa)比基体(119和202MPa)分别提高了105.9%、57.9%。磨损试验结果表明,添加石墨烯和T6热处理后复合材料的磨损率最低,磨损机制由剥层磨损转变为磨粒磨损。 展开更多
关键词 石墨烯 铝基复合材料 热处理 显微组织 耐磨性能
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富含半胱氨酸的酸性分泌蛋白在肿瘤中的研究进展
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作者 张娜 孔英君 +1 位作者 刘航 代灿 《现代肿瘤医学》 CAS 2024年第10期1945-1948,共4页
富含半胱氨酸的酸性分泌蛋白(secreted protein acidic and rich in cysteine, SPARC)是肿瘤微环境中重要的基质成分,它作为正常细胞恶变和肿瘤发生发展过程中一个重要的分子,能够调节多种肿瘤相关细胞因子及其受体的相互作用,并调节多... 富含半胱氨酸的酸性分泌蛋白(secreted protein acidic and rich in cysteine, SPARC)是肿瘤微环境中重要的基质成分,它作为正常细胞恶变和肿瘤发生发展过程中一个重要的分子,能够调节多种肿瘤相关细胞因子及其受体的相互作用,并调节多种信号通路以及蛋白水解酶的表达水平。由于它抑制和促进肿瘤进展的能力取决于细胞类型、肿瘤分期等,因此在多种类型的肿瘤中差异表达,并可能成为肿瘤早期诊断的新型生物标记物以及治疗的新靶点。本文就近年来SPARC在肿瘤研究中的进展作一综述。 展开更多
关键词 富含半胱氨酸的酸性分泌蛋白 肿瘤 细胞外基质 预后及治疗
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A multi-objective decision-making method for the treatment scheme of landslide hazard 被引量:7
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作者 QuanminXie YuanyouXia 《Journal of University of Science and Technology Beijing》 CSCD 2004年第2期101-105,共5页
The treatment engineering of landslide hazard is a complicated systemengineering. The selecting treatment scheme is influenced by many factors such as technology,economics, environment, and risk. The decision-making o... The treatment engineering of landslide hazard is a complicated systemengineering. The selecting treatment scheme is influenced by many factors such as technology,economics, environment, and risk. The decision-making of treatment schemes of landslide hazard is aproblem of comprehensive judgment with multi-hierarchy and multi-objective. The traditional analysishierarchy process needs identity test. The traditional analysis hierarchy process is improved bymeans of optimal transfer matrix here. An improved hierarchy decision-making model for the treatmentof landslide hazard is set up. The judgment matrix obtained by the method can naturally meet therequirement of identity, so the identity test is not necessary. At last, the method is applied tothe treatment decision-making of the dangerous rock mass at the Slate Mountain, and its applicationis discussed in detail. 展开更多
关键词 landslide hazard treatment scheme improved hierarchy decision-making model optimal transfer matrix
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芯片用金刚石增强金属基复合材料研究进展 被引量:1
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作者 杜小东 何佳雯 +4 位作者 陈威 王长瑞 田威 廖文和 何晓璇 《电子机械工程》 2024年第1期1-12,共12页
随着电子设备集成化程度越来越高,对高导热封装材料的需求也越来越大,金刚石增强金属基复合材料凭借其高导热性能成为研究焦点。然而,由于金刚石颗粒与金属基体之间的不润湿特性,具有高导热性的金刚石增强金属基复合材料难以制备。文中... 随着电子设备集成化程度越来越高,对高导热封装材料的需求也越来越大,金刚石增强金属基复合材料凭借其高导热性能成为研究焦点。然而,由于金刚石颗粒与金属基体之间的不润湿特性,具有高导热性的金刚石增强金属基复合材料难以制备。文中综述了金刚石增强金属基复合材料的研究进展,包括界面改性、工艺参数优化和复合材料制备方法,并指出了金刚石增强金属基复合材料目前存在的问题和今后的研究方向。 展开更多
关键词 金刚石增强金属基复合材料 热导率 表面处理 界面结合 烧结温度
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转化生长因子β/Smad信号通路与瘢痕疙瘩的靶向治疗 被引量:5
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作者 姚思琦 黎文正 汪虹 《中国组织工程研究》 CAS 北大核心 2024年第16期2619-2624,共6页
背景:关于瘢痕疙瘩的发病机制目前尚不完全清楚。近年来瘢痕疙瘩涉及的发病机制有一些新的研究进展,包括转化生长因子β(transforming growth factor-β,TGF-β)/Smad信号通路、缺血缺氧、缺氧诱导因子1(HIF-1)、丝裂原活化蛋白激酶(MA... 背景:关于瘢痕疙瘩的发病机制目前尚不完全清楚。近年来瘢痕疙瘩涉及的发病机制有一些新的研究进展,包括转化生长因子β(transforming growth factor-β,TGF-β)/Smad信号通路、缺血缺氧、缺氧诱导因子1(HIF-1)、丝裂原活化蛋白激酶(MAPK)通路等。TGF-β/Smad通路目前研究较为清晰,TGF-β/Smad通路的激活促进瘢痕疙瘩的发展。目的:对TGF-β/Smad信号通路进行综述并评估以该通路为靶点的主要治疗策略,以期有助于临床拓展更有效的治疗方式。方法:用计算机检索PubMed、Web of Science数据库等英文数据库及中国知网、万方数据知识服务平台等中文数据库,检索从2017年1月至2023年4月发表的文献,英文检索词为“Keloid,Fibroblasts,TGF-β/Smad,Extracellular Matrix,Collagen,Treatment Measures”,中文检索词为“瘢痕疙瘩,成纤维细胞,转化生长因子β/Smad,细胞外基质,胶原,治疗措施”。根据纳入和排除标准最终纳入72篇文献进行结果分析。结果与结论:①总结了TGF-β/Smad信号通路在瘢痕疙瘩发生发展中的作用机制:TGF-β1和TGF-β2在瘢痕疙瘩中呈现过表达状态,而TGF-β3表现出抗纤维化作用;Smad2/3与Smad1/5/8同Smad4结合形成复合物进入细胞核发挥纤维化作用,而Smad6/7呈现抑制瘢痕疙瘩增生的作用;②TGF-β/Smad通路目前在瘢痕疙瘩中的研究最为清晰,列举了多条通过靶向抑制该通路激活的途径,可较大程度达到抑制瘢痕疙瘩发生发展的目的;③瘢痕疙瘩目前还未有单一的临床金标准治疗方式,单靠抑制TGF-β/Smad通路还不能完全抑制瘢痕疙瘩的发展,还需要综合考虑全身各个系统之间同瘢痕疙瘩的联系。尽管已经在纤维化级联反应中发现了很多有希望的靶点,但在临床中还需要更多研究来转化为靶向治疗。 展开更多
关键词 瘢痕疙瘩 成纤维细胞 TGF-Β/SMAD 细胞外基质 胶原蛋白 治疗措施
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Micro-yield behaviors of Al_2O_3-SiO_(2(sf))/Al-Si metal matrix composites 被引量:1
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作者 刘贯军 李文芳 +1 位作者 彭继华 杜军 《中国有色金属学会会刊:英文版》 EI CSCD 2007年第2期307-312,共6页
Effects of the volume fraction and the size of crystallized alumina silicate short fibers as well as heat treatment processes on micro-yield strength(MYS) of Al2O3-SiO2(sf)/Al-Si metal matrix composite(MMC) that was f... Effects of the volume fraction and the size of crystallized alumina silicate short fibers as well as heat treatment processes on micro-yield strength(MYS) of Al2O3-SiO2(sf)/Al-Si metal matrix composite(MMC) that was fabricated by squeezing cast, were investigated by using continuous loading method on an Instron 5569 tester with a special extensometer with an accuracy of 10?7. The results show that MYS of MMC decreases with the increase of volume fraction and length of the alumina silicate short fibers in the metal matrix composite, respectively. MYS of quenched Al2O3-SiO2(sf)/Al-Si MMC is the lowest, MYS of the MMC through peak-aging treatment is higher than that through other heat treatment methods. And before the peak-aging, MYS of MMC aging treated gradually increases with the increase of the aging time. Aging treatment after solution treatment is a preferred way that enhances micro and macro-yield strength of Al2O3-SiO2(sf)/Al-Si MMC. 展开更多
关键词 Al-Si金属基复合材料 硅酸铝 微蠕变行为 屈服
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基质金属蛋白酶-13在多发性骨髓瘤中的作用研究
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作者 贾海英 郭淑丽 +2 位作者 余亮 黄国虹 王昌敏 《中国实验血液学杂志》 CAS CSCD 北大核心 2024年第6期1776-1780,共5页
目的:探讨基质金属蛋白酶-13(MMP-13)在多发性骨髓瘤(MM)疾病发生发展及病情判断、预后评估等方面的作用。方法:收集MM患者57例、正常对照人群45例,采用实时荧光定量PCR检测研究对象MMP-13基因mRNA表达水平,比较MM患者组和正常对照组MMP... 目的:探讨基质金属蛋白酶-13(MMP-13)在多发性骨髓瘤(MM)疾病发生发展及病情判断、预后评估等方面的作用。方法:收集MM患者57例、正常对照人群45例,采用实时荧光定量PCR检测研究对象MMP-13基因mRNA表达水平,比较MM患者组和正常对照组MMP-13 mRNA表达水平的差异,分析MMP-13与MM骨病及其严重程度、ISS分期、DS分期及治疗效果的关系。结果:MM患者MMP-13mRNA表达水平较正常对照组显著升高(P<0.05);有骨病的MM患者较无骨病的患者MMP-13 mRNA明显升高,且骨病越严重升高越明显(P<0.05);ISS分期及DS分期Ⅰ期与Ⅲ期患者之间MMP-13 mRNA差异也有统计学意义(P<0.05);患者治疗后较治疗前MMP-13明显下降(P<0.05)。结论:MMP-13基因mRNA表达水平与MM发生发展相关,其表达水平在病情判断、预后评估等方面具有一定的指导意义。 展开更多
关键词 MMP-13 多发性骨髓瘤 骨髓瘤骨病 分期 疗效
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镍基单晶高温合金γ基体相通道研究
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作者 陈忠 田庚方 +2 位作者 李天富 王子军 陈东风 《热加工工艺》 北大核心 2024年第6期88-92,共5页
镍基单晶合金在高温下具备良好的力学性能,是航空航天及核能领域的关键材料。通过对铸态、力加载及热处理状态的变化研究了第三代镍基单晶高温合金DD10的γ基体相通道演化,并对铸态样品利用四圆中子衍射做了单晶性检测。结果表明,DD10在... 镍基单晶合金在高温下具备良好的力学性能,是航空航天及核能领域的关键材料。通过对铸态、力加载及热处理状态的变化研究了第三代镍基单晶高温合金DD10的γ基体相通道演化,并对铸态样品利用四圆中子衍射做了单晶性检测。结果表明,DD10在[200]、[020]、[002]晶面的单晶性能良好;经力加载和热处理后γ基体相通道有序性增加,通道宽度增加,且在力加载的γ基体相通道中析出二次沉淀强化相;900℃热处理后,γ基体相通道中的Co、Cr元素含量显著增加,在相同的竖直通道中Co元素含量一致;在相同的水平通道中Cr元素含量则保持一致;Mo、Re、W等微量元素经热处理后更多的从γ基体相通道中进入到沉淀强化相中。 展开更多
关键词 镍基单晶高温合金 中子衍射 γ基体相通道 热处理
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高温处理对聚乙烯纤维-钢纤维高韧性水泥基复合材料抗折性能的影响
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作者 张港 谢群 +1 位作者 于晓伟 赵鹏 《济南大学学报(自然科学版)》 CAS 北大核心 2024年第6期749-754,762,共7页
为了探究高韧性水泥基复合材料经高温处理后的力学性能,采用聚乙烯纤维与钢纤维混杂方式制备一种混杂纤维高韧性水泥基复合材料,通过三点抗折试验探讨所制得聚乙烯纤维-钢纤维高韧性水泥基复合材料经温度20、60、100、150、200、250℃... 为了探究高韧性水泥基复合材料经高温处理后的力学性能,采用聚乙烯纤维与钢纤维混杂方式制备一种混杂纤维高韧性水泥基复合材料,通过三点抗折试验探讨所制得聚乙烯纤维-钢纤维高韧性水泥基复合材料经温度20、60、100、150、200、250℃处理后的抗折性能。结果表明:随着处理温度的升高,该复合材料的开裂应力、峰值应力和弯曲韧性均表现为先增大后减小的变化规律,处理温度为60、150℃时最大开裂应力为12.09 MPa,最大峰值应力为18.52 MPa;峰值应力受处理温度的影响较显著,当处理温度为200、250℃时,聚乙烯纤维熔化,复合材料的峰值应力相较于处理温度为150℃时的分别减小42.7%、57.9%;该复合材料的弯曲韧性在指定挠度为L/150、L/100(其中L为支座间跨度)阶段受处理温度影响较小,在指定挠度为L/50、L/25阶段,随着处理温度的升高而先增大后减小,聚乙烯纤维熔化导致复合材料在大挠度阶段的弯曲韧性明显减小。 展开更多
关键词 高韧性水泥基复合材料 高温处理 抗折性能 弯曲韧性 聚乙烯纤维 钢纤维
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高温热处理对C/C复合材料组织结构和拉伸性能的影响
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作者 钮超 贾建刚 +1 位作者 伏芳杏 潘子康 《西安工业大学学报》 CAS 2024年第4期424-431,共8页
为了缓解C/C复合材料的脆性,使用自制的热梯度化学气相沉积(TG-CVI)设备对单向碳纤维预制体进行致密化,制备得到致密的C/C复合材料。通过高温热处理调节界面的结合强度和基体碳的石墨化程度,利用排水法测试复合材料的密度,万能材料试验... 为了缓解C/C复合材料的脆性,使用自制的热梯度化学气相沉积(TG-CVI)设备对单向碳纤维预制体进行致密化,制备得到致密的C/C复合材料。通过高温热处理调节界面的结合强度和基体碳的石墨化程度,利用排水法测试复合材料的密度,万能材料试验机测试其拉伸性能,采用可视化石墨烯片层技术(VGT)对试样进行处理,使用偏光显微镜(PLM)、扫描电子显微镜(SEM)、X-射线衍射(XRD)分别研究复合材料的微观组织、界面和断面形貌、以及物相组成。结果表明,在相同沉积条件下,热处理后的C/C复合材料碳基体的石墨化程度提高,界面结合强度下降,拉伸性能下降。但复合材料最初的脆性断裂向拟延性转变,延伸率提高。 展开更多
关键词 C/C复合材料 高温热处理 热解碳基体 拉伸性能
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活血通窍汤辅助治疗对动脉瘤性蛛网膜下腔出血并发脑血管痉挛临床疗效及对血清基质金属蛋白酶-9同型半胱氨酸和可溶性细胞间黏附分子-1水平的影响
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作者 宋金辉 余丹华 +1 位作者 周金丽 施婵宏 《中国药物与临床》 CAS 2024年第20期1304-1308,共5页
目的分析活血通窍汤辅助治疗对动脉瘤性蛛网膜下腔出血(SAH)并发脑血管痉挛(CVS)挛患者临床疗效及对血清基质金属蛋白酶(MMP)-9、同型半胱氨酸(Hcy)和人可溶性细胞间黏附分子-1(sICAM-1)的影响。方法选择浙江省义乌市中心医院2021年4月... 目的分析活血通窍汤辅助治疗对动脉瘤性蛛网膜下腔出血(SAH)并发脑血管痉挛(CVS)挛患者临床疗效及对血清基质金属蛋白酶(MMP)-9、同型半胱氨酸(Hcy)和人可溶性细胞间黏附分子-1(sICAM-1)的影响。方法选择浙江省义乌市中心医院2021年4月至2022年4月收治的SAH并发CVS患者78例,运用随机数字表法分为对照组(39例)与治疗组(39例)。对照组给予盐酸法舒地尔注射液治疗,治疗组在对照组基础上服用活血通络汤。2组均治疗2周。比较2组治疗疗效,治疗前后中医证候积分、血流动力学、神经功能和认知功能、MMP-9、Hcy和sICAM-1水平变化。结果治疗组总有效率高于对照组(P<0.05)。2组治疗后患者头痛、恶心呕吐和颈项抵抗积分较治疗前降低(P<0.05),治疗组低于对照组(P<0.05)。2组治疗后颈内动脉颅外段平均注速(VICA-Vm)和大脑中动脉平均注速(MCA-Vm)较治疗前降低(P<0.05),治疗组治疗后低于对照组(P<0.05)。2组治疗后mRS评分较治疗前降低,MoCA评分较治疗前升高(P<0.05);治疗组治疗后改良Rankin量表(mRS)评分低于对照组,蒙特利尔认知评估量表(MoCA)评分高于对照组(P<0.05)。2组治疗后MMP-9、Hcy和sICAM-1水平较治疗前降低(P<0.05);治疗组治疗后MMP-9、Hcy和sICAM-1水平低于对照组(P<0.05)。结论活血通窍汤辅助治疗SAH并发CVS患者疗效良好,患者血流动力学改善,神经功能改善,可降低MMP-9、Hcy和sICAM-1水平。 展开更多
关键词 蛛网膜下腔出血 血管痉挛 颅内 治疗结果 基质金属蛋白酶9 同型半胱氨酸 可溶性细胞间黏附分子-1
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