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Sintering behavior of Cr in different atmospheres and its effect on the microstructure and properties of copper-based composite materials

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1208-1213页

作者： Ye Wang qing-zhi Yan Fei-fei Zhang Chang-chun Ge Xiao-lu Zhang hai-qin zhao Laboratory of Special Ceramics and Powder Metallurgy University of Science and Technology Beijing Beijing Railway Star Fortune Technology Co. Ltd. CSR qingdao Sifang Locomotive & Rolling Stock Co. Ltd.

Copper matrix composites consisting of chromium （Cr） or ferrochrome （Cr-Fe） as strengthening elements and molybdenum disulfide as a lubricant had been sintered in nitrogen and hydrogen atmosphere, respectively. Their morphology and energy-dispersive X-ray spectrometry （EDS） analysis showed that serious interaction occurred between MoS2 and Cr （or Cr-Fe） particles when the samples were sintered in hydrogen atmosphere. Chromium sulfide compound （CrxSy） was formed as a reaction product, which decreased the density and strength of the composites remarkably. This interaction was inhibited when the samples were sintered in nitrogen atmosphere; thus, the mechanical properties of the composites were improved.

关键词： metallic matrix composites microstructure mechanical properties chromium ferrochrome sintering

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幂零群的若干等价条件

西南师范大学学报（自然科学版） 2005年第1期30卷 26-30页

作者：张勤海赵俊英山西师范大学数学与计算机科学学院山西临汾041004

利用共轭置换子群的概念研究群的幂零性问题. 获得了一个群为幂零群的几个等价条件和若干充分条件.

关键词：共轭置换子群内幂零群幕零群无不动点的自同构

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三种术式治疗套袖状髌骨上极骨折的疗效分析

中国现代手术学杂志 2016年第5期20卷 351-353页

作者：张建海赵勤鹏西安市高陵区医院西安710200 西安市红会医院西安710054

目的探讨套袖状髌骨上极骨折治疗的理想手术方式。方法选取2011年6月至2014年6月期间我院接收的84例髌骨上极骨折患者,将入选者根据手术方式不同分为张力带组(Krackow法缝合编织股四头肌腱并"8"字张力带钢丝固定法,n=28)、缝合组(采用Kr... 详细信息

目的探讨套袖状髌骨上极骨折治疗的理想手术方式。方法选取2011年6月至2014年6月期间我院接收的84例髌骨上极骨折患者,将入选者根据手术方式不同分为张力带组(Krackow法缝合编织股四头肌腱并"8"字张力带钢丝固定法,n=28)、缝合组(采用Krackow法缝合编织股四头肌腱固定法,n=28)、聚髌器组(聚髌器固定法,n=28),观察三组治疗疗效、手术情况及膝关节功能评分情况。结果术后6个月时,张力带组临床优良率显著高于缝合组、聚髌器组(P<0.05);术后6个月时,张力带组膝关节功能评分明显高于其他两组(P<0.05)。结论套袖状髌骨上极骨折采用Krackow法缝合编织股四头肌腱并"8"字张力带钢丝固定法治疗,疗效显著,可快速恢复病人患肢功能,具有推广价值。

关键词：髌骨骨折骨折固定术,内

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关于可逆矩阵的Bruhat分解定理的注记

山西师范大学学报（自然科学版） 2002年第2期16卷 1-4页

作者：张勤海赵俊龙山西师范大学数学与计算机科学学院山西临汾041004

在这篇注记里 ,基于可逆矩阵的 Bruhat分解定理 ,我们获得了可逆矩阵的另外三种分解形式 .

关键词：可逆矩阵 Bruhat分解定理置换矩阵初等矩阵

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying Liu Bei Peng Xiaoyan Zhou Lixia qin Lingyan Liang Yichen Wei qingping Zhang Xiaocheng Li haixia qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming zhao Jun Liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

过表达亚甲基四氢叶酸脱氢酶对高山被孢霉脂质合成的影响

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中国生物工程杂志 2018年第9期38卷 12-18页

作者：汪企再王鸿超陈海琴赵建新张灏陈卫陈永泉江南大学食品学院

高山被孢霉是一种富含多不饱和脂肪酸的丝状真菌,但其脂质过程中NADPH的来源还没有研究透彻。以高山被孢霉（尿嘧啶营养缺陷型）作为出发菌株,研究亚甲基四氢叶酸脱氢酶（MTHFD1）对高山被孢霉脂质合成的影响。首先构建了过表达载体pBIG... 详细信息

高山被孢霉是一种富含多不饱和脂肪酸的丝状真菌,但其脂质过程中NADPH的来源还没有研究透彻。以高山被孢霉（尿嘧啶营养缺陷型）作为出发菌株,研究亚甲基四氢叶酸脱氢酶（MTHFD1）对高山被孢霉脂质合成的影响。首先构建了过表达载体pBIG2-ura5s-MTHFD1,采用根癌土壤杆菌介导转化真菌的方法,将二元表达载体转化进高山被孢霉CCFM501中,在筛选培养基SC-CS平板上进行筛选,进而得到稳定遗传MTHFD1基因的过表达菌株（MA-MTHFD1）;其次提取MA-MTHFD1菌株基因组进行PCR鉴定,并结合qPCR分析结果,表明MTHFD1基因成功在高山被孢霉中实现了过量表达;最后通过对MA-MTHFD1中的脂肪酸含量、NADPH含量及NADPH合成途径中相关基因转录水平进行分析,研究MTHFD1基因过表达对脂质合成的影响。实验结果表明,过表达MTHFD1基因可以提高高山被孢霉脂质合成能力。与原养型高山被孢霉相比,MA-MTHFD1菌株中脂肪酸含量提高了40.13%,NADPH的含量提高了26.45%,而且NADPH合成途径中其他相关基因苹果酸酶（ME）和异柠檬酸脱氢酶（IDH）的转录水平也发生了上调。这一系列研究结果表明,在高山被孢霉脂质合成还原力形成中,MTHFD1基因起到了关键作用。这为解析高山被孢霉中NADPH来源及深入研究脂质合成机制,从而对其胞内脂肪酸代谢通路进行分子水平上的改建提供了一定的理论依据。

关键词：亚甲基四氢叶酸脱氢酶高山被孢霉脂质合成 NADPH

Hemoglobin integrated red blood cell membrane-coated metalorganic framework nano-platform for improving the self-adaptive blood glucose management

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Nano Research 2025年第1期18卷 618-627页

作者： Shuai Wu Li Zhu Sheng Ni Xiong zhao Meng Yan Yuan Zhong Karissa Kusuma Yi Liang Kaiwen Bao Kai Qu Xian qin Kun Zhang Wuquan Deng Da Sun Wei Wu Key Laboratory of Biorheological Science and Technology Ministry of EducationCollege of BioengineeringChongqing UniversityChongqing 400044China Chongqing University Three Gorges Hospital Chongqing Municipality Clinical Research Center for Endocrinology and Metabolic DiseasesChongqing 404000China Institute of Life Sciences&Biomedical Collaborative Innovation Center of Zhejiang Province Wenzhou UniversityWenzhou 325035China Department of Endocrinology School of MedicineChongqing Emergency Medical CenterChongqing University Central HospitalChongqing 400014China

Diabetes,a prevalent chronic metabolic disorder,often leads to severe ***,existing treatment methods may pose life-threatening risks due to poor patient compliance and inaccurate dosing of subcutaneous insulin ***,a biomimetic red blood cell(RBC)membrane-coated glucose-responsive nanoplatform is developed for controlling insulin *** nanoplatforms with RBC membrane can prolong the half-life of nano-formulation in vivo mediated by the biomimetic immune ***,the cascade catalytic effect of glucose oxidase(GOx)encapsulated in metal-organic frameworks(MOFs)and hemoglobin(Hb)in the RBC membrane are able to not only facilitate glucose-responsive insulin release,but also eliminate the detrimental by-product hydrogen peroxide(H_(2)O_(2))resulting from the Hb mediated H_(2)O_(2)*** in vitro and in vivo studies have demonstrated the favorable glucose-responsive performances of this advanced nano-platform with a single intravenous injection maintaining blood glucose balance in Type 1 Diabetes(T1D)mice for an extended duration without the hypoglycemia ***,this biomimetic insulin delivery system is poised to function as a strategy for the intravenous insulin administration,offering a promising drug candidate for the self-adaptive long-term T1D treatment.

关键词： glucose-responsive metal-organic frameworks red blood cell membrane insulin delivery glucose oxidase hemoglobin

Association between complement factor I gene polymorphisms and the risk of age-related macular degeneration:a Meta-analysis of literature

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International Journal of Ophthalmology(English edition) 2016年第2期9卷 298-305页

作者： qin Wang hai-Sheng zhao Li Li Department of Ophthalmology the Second Affiliated Hospital of Chongqing Medical University Center of Ophthalmology the Second Affiliated Hospital of Chongqing Medical University

AIM： To systematically review the association between complement factors I （CFI） polymorphisms and age- related macular degeneration （AMD） and to explore whether CFI polymorphisms are associated with AMD, METHODS： Meta-analysis of articles published from 1995 to January 2015 of articles involved with AMD and polymorphisms of the CFI gene. Eligible data were pooled in a Meta-analysis, analyzing using STATA software （version 12.0）, Review Manager （version 5.2） and different models based on the heterogeneity of effect sizes. Egger＇s test, Begg＇s rank correlation methods were used to evaluate for publication bias.~ RESULTS： Thirteen articles were eligible, describing two loci polymorphisms of the CFI gene （of which 12 articles focus on rs10033900T〉C and 3 articles focus on rs2285714C〉T）. For rs10033900T〉C, the results of our study revealed that having a mutant allele C, TC, CC and TC＋CC was associated with a decreased risk of AMD in all population groups studied （C versus T models, OR=0.84, 95%Ch 0.72-0.99, P=0.04; TC versus TT models OR= 0.89, 95%Ch 0.88-0.99, P=0.04;CC versus ＂1-1＂ models, OR=0.76, 95%Ch 0.60-0.98, P=-0.03; TC＋CC versus TT models, OR=0.81, 95%Ch0.65-0.99, P=0.04）. We found that C allele were related to lower AMD risk in the Caucasian population by subgroup analysis, but there was no association with AMD under the allele and genotypes comparison in Asian studies. For rs2285714 C〉T, the TC, TT genotypes contributed to a higher risk of AMD, compared with the CC carriers and CT＋CC （OR=1.34, 95%Ch 1.09-1.63, P=0.004; OR=1.50, 95%Ch 1.25-1.80, P〈0.0001）. CONCLUSION： This Meta-analysis suggests that CFI rs10033900T〉C and rs2285714C〉T polymorphisms may contribute to AMD.

关键词： complement factors I age-related maculardegeneration age-related maculopathy single-nucleotidepolymorphisms Meta-analysis

Application of rare-earth element Y in refining impure copper

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 453-459页

作者： hai-hong Li Xue-qin Sun Shang-zhou Zhang qin-yi zhao Guang-zhen Wang School of Environment and Materials Engineering Yantai University

The effects of rare-earth element Y in refining impure copper were investigated in this paper. The composition, microstructures, and corrosion resistance properties of impure copper before and after refinement with Y were investigated using direct-reading spectrometry, inductively coupled plasma atomic emission spectrometry, optical microscopy, scanning electron microscopy, and potentiodynamic polariza- tion measurements. The results show that the concentrations of impurities S, As, Sb, Bi, A1, Cd, and Se are remarkably decreased. Adding an appropriate amount of Y refines the microstructure and enhances the corrosion resistance properties of impure copper in HC1 solution via a purification effect. The formation enthalpies of compounds formed between Y and various impurity elements were calculated on the basis of Miedema＇s theory. The thermodynamic mechanisms of the refinement of impure copper by Y were also discussed.

关键词： copper refining yttrium addition impurities removal microstructure corrosion resistance