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Expression of peroxisome proliferator-activated receptor γ,E-cadherin and matrix metalloproteinases-2 in gastric carcinoma and lymph node metastases 被引量:23
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作者 HE Qing CHEN Jie +2 位作者 LIN Han-liang HU Pin-jin CHEN Min-hu 《Chinese Medical Journal》 SCIE CAS CSCD 2007年第17期1498-1504,共7页
Background Peroxisome proliferator activated receptor γ (PPARγ) is a ligand-activated transcription factor. Activation of PPARγ has recently been demonstrated to inhibit various tumor cells growth, progression an... Background Peroxisome proliferator activated receptor γ (PPARγ) is a ligand-activated transcription factor. Activation of PPARγ has recently been demonstrated to inhibit various tumor cells growth, progression and metastasis. E-cadherin-mediated cell adhesion system is now considered to be an “invasion suppressor system” in cancer tissues. Matrix metalloproteinases-2 (MMP-2) is a prerequisite for metastasizing tumor cells. However their correlation is still unknown in gastric carcinoma. The aim of this study was to assess the expression of PPAR7, E-cadherin, MMP-2 and their correlation in gastric carcinoma and metastases. Methods Gastric carcinoma tissues and their corresponding lymph nodes with metastases and the adjacent non-tumor tissues were obtained from 54 patients with gastric cancer who underwent gastrectomy. Expression of PPARγ, E-cadherin and MMP-2 was assessed by immunohistochemical staining. Results The nuclear expression level of PPARγ in neoplastic cells was significantly lower than that in the normal controls (P〈0.001), with the expression of PPARγ being weaker in primary tumors compared with that in metastases. In all neoplastic cells, E-cadherin was expressed with abnormal patterns (cytoplasm pattern, cytoplasm and membrane pattern or absent), compared with normal cells where E-cadherin was expressed with a normal pattern (membrane pattern). Compared with the normal tissues, the expression level of E-cadherin decreased in primary tumors and further decreased in metastases (P〈0.001). Membrane staining of MMP-2 was detected in the foveolar epithelia of normal gastric mucosa, whereas predominant cytoplasm staining of MMP-2 was found in malignant tissues. The expression of MMP-2 was stronger in metastatic tissues than in primary tumors. In neoplastic foci the expression of PPARγ was negatively correlated with MMP-2 expression (P〈0.05). However, there was no correlation between E-cadherin and PPARγ or MM P-2 expression. Conclusions Down-regulation of PPARγ and E-cadherin and up-regulation of MMP-2 in neoplastic foci might be helpful to gastric carcinogenesis and metastases. An inverse relationship between PPARγ and MMP-2 in human gastric carcinoma suggests that PPARγ might modulate MMP-2 expression and affect gastric cancer metastases. 展开更多
关键词 peroxisome proliferator-activated receptor γ E-cadherin matrix metalloproteinases-2 gastric carcinoma METASTASES
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Recent progress in ternary mixed matrix membranes for CO_(2) separation 被引量:1
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作者 Zikang Qin Yulei Ma +13 位作者 Jing Wei Hongfang Guo Bangda Wang Jing Deng Chunhai Yi Nanwen Li Shouliang Yi Yi Deng Wentao Du Jian Shen Wenju Jiang Lu Yao Lin Yang Zhongde Dai 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期831-858,共28页
Mixed matrix membranes(MMMs)could combine the advantages of both polymeric membranes and porousfillers,making them an effective alternative to conventional polymer membranes.However,interfacial incompatibility issues,s... Mixed matrix membranes(MMMs)could combine the advantages of both polymeric membranes and porousfillers,making them an effective alternative to conventional polymer membranes.However,interfacial incompatibility issues,such as the presence of interfacial voids,hardening of polymer chains,and blockage of micropores by polymers between common MMMsfillers and the polymer matrix,currently limit the gas sep-aration performance of MMMs.Ternary phase MMMs(consisting of afiller,an additive,and a matrix)made by adding a third compound,usually functionalized additives,can overcome the structural problems of binary phase MMMs and positively impact membrane separation performance.This review introduces the structure and fabrication processes for ternary MMMs,categorizes various nanofillers and the third component,and summarizes and analyzes in detail the CO_(2) separation performance of newly developed ternary MMMs based on both rubbery and glassy polymers.Based on this separation data,the challenges of ternary MMMs are also discussed.Finally,future directions for ternary MMMs are proposed. 展开更多
关键词 CO_(2) separation Mixed matrix membranes Ternary phase
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Lichong decoction reduces Matrix Metalloproteinases-2 expression but increases Tissue Inhibitors of Matrix Metalloproteinases-2 ex-pression in a rat model of uterine leiomyoma 被引量:12
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作者 Wang Yasong Li Donghua +7 位作者 Xu Xin Qian Ruiya Zhang Yalan Huang Yuhua Geng Jianguo Zou Xiaoli Han Hon-gjuan Zhang Wufang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2016年第4期479-485,共7页
OBJECTIVE:To study the effect of Lichong decoction(LD) on expression of matrix metalloproteinase-2(MMP-2) and metalloproteinase-2(TIMP-2) in a rat model of uterine leiomyoma(UL).METHODS:UL was induced in rats using ex... OBJECTIVE:To study the effect of Lichong decoction(LD) on expression of matrix metalloproteinase-2(MMP-2) and metalloproteinase-2(TIMP-2) in a rat model of uterine leiomyoma(UL).METHODS:UL was induced in rats using exogenous estrogen and progesterone.LD was administered(p.o.) for 4 weeks,and mifepristone(RU-486)used as a control.To observe the effect of LD on the uterine coefficient and uterine transverse diameter,a radioimmunoassay method was used to detect serum levels of sex hormones.Light microscopic analyses of pathologic changes in the tissues of UL rats were evaluated.Expression of the proteins of matrix metalloproteinases(MMPs) and tissue inhibitors of metalloproteinases(TIMPs) in uterine tissues was assessed by immunohistochemical staining and western blotting.RESULTS:A UL model in rats was established successfully.LD reduced uterine weight,uterine coefficient,and uterine transverse diameter compared with untreated controls.LD reduced levels of estradiol,progesterone,follicle-stimulating hormone,and luteinizing hormone in our UL models.LD improved the pathologic condition of uterine muscle.Expression of MMP-2 protein decreased to varying extents in LD-treated groups,but TIMP-2 levels were enhanced.LD appears to reduce MMP-2 expression and increase TIMP-2 expression in UL tissue.CONCLUSION:These data suggest that the mechanism of action of LD on ULs may involve reduction of MMP-2 expression and increase in TIMP-2 expression in rats. 展开更多
关键词 LEIOMYOMA matrix metalloproteinase 2 Tissue inhibitor of metalloproteinase-2 Lichong decoction
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Association between Gene Polymorphisms and SNP-SNP Interactions of the Matrix Metalloproteinase 2 Signaling Pathway and the Risk of Vascular Senescence
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作者 LIAO Zhen Yu YANG Shuo +3 位作者 HU Song LIU Jia MAO Yong Jun SUN Shu Qin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第2期146-156,共11页
Objective This study aimed to explore the association of single nucleotide polymorphisms(SNP)in the matrix metalloproteinase 2(MMP-2)signaling pathway and the risk of vascular senescence(VS).Methods In this cross-sect... Objective This study aimed to explore the association of single nucleotide polymorphisms(SNP)in the matrix metalloproteinase 2(MMP-2)signaling pathway and the risk of vascular senescence(VS).Methods In this cross-sectional study,between May and November 2022,peripheral venous blood of151 VS patients(case group)and 233 volunteers(control group)were collected.Fourteen SNPs were identified in five genes encoding the components of the MMP-2 signaling pathway,assessed through carotid-femoral pulse wave velocity(cf PWV),and analyzed using multivariate logistic regression.The multigene influence on the risk of VS was assessed using multifactor dimensionality reduction(MDR)and generalized multifactor dimensionality regression(GMDR)modeling.Results Within the multivariate logistic regression models,four SNPs were screened to have significant associations with VS:chemokine(C-C motif)ligand 2(CCL2)rs4586,MMP2 rs14070,MMP2rs7201,and MMP2 rs1053605.Carriers of the T/C genotype of MMP2 rs14070 had a 2.17-fold increased risk of developing VS compared with those of the C/C genotype,and those of the T/T genotype had a19.375-fold increased risk.CCL2 rs4586 and MMP-2 rs14070 exhibited the most significant interactions.Conclusion CCL2 rs4586,MMP-2 rs14070,MMP-2 rs7201,and MMP-2 rs1053605 polymorphisms were significantly associated with the risk of VS. 展开更多
关键词 Vascular senescence Pulse wave velocity(PWV) Single nucleotide polymorphism(SNP) matrix metalloproteinase 2(MMP-2) Extracellular matrix(ECM) Structural degradation Multifactor dimensionality reduction(MDR)
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A nonwoven supported mixed matrix membrane for CH4/N2 separation
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作者 Yuntao Liang Yongjing Wang +2 位作者 Wenbin Feng Jingkai Xu Wei Xiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期101-108,共8页
Efficiently enriching low-concentration CH4 is pivotal for enhancing the utilization of unconventional energy sources and mitigating greenhouse gas emissions.This study focuses on modifying the overall performance of ... Efficiently enriching low-concentration CH4 is pivotal for enhancing the utilization of unconventional energy sources and mitigating greenhouse gas emissions.This study focuses on modifying the overall performance of CH_(4)/N_(2)separation membranes.A novel mixed matrix membrane(MMM)with a reinforced substrate structure was developed through a straightforward dip-coating technique.This MMM incorporates a polytetrafluoroethylene(PTFE)porous membrane as the supporting framework,while a composite of block polymer(styrene-butadiene-styrene)and metal-organic framework(Ni-MOF-74)forms the selective separation layer.Comprehensive characterization of Ni-MOF-74 and the fabricatedmembranes was conducted using X-rays diffraction,scanning electron microscope,Brunauer-Emmett-Teller analysis,and gas permeance tests.The findings indicate a robust integration of the PTFE porous support with the membrane layer,enhancing the mechanical stability of theMMM.Under optimal conditions,the mechanical strength of the PM20 membrane(containing 20%Ni-MOF-74)was observed to be 37.7 MPa,representing remarkable increase compared to the non-reinforcedMMM.Additionally,thePM20membrane exhibited an impressive CH4 permeation rate of 92 barrer(1 barrer﹦3.35×10^(-16)mol·m·m^(-2)·s^(-1)·Pa^(-1))alongside a CH_(4)/N_(2)selectivity of 4.18.These results underscore the MMM's substantial performance and its promising potential in methane enrichment applications. 展开更多
关键词 Mixed matrix membrane CH_(4)/N_(2)separation MOF fillers Porous skeleton
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Long noncoding RNAs HAND2-AS1 ultrasound microbubbles suppress hepatocellular carcinoma progression by regulating the miR-873-5p/tissue inhibitor of matrix metalloproteinase-2 axis
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作者 Qiang Zou Hao-Wen Wang +2 位作者 Xi-Liang Di Yuan Li Hui Gao 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1547-1563,共17页
BACKGROUND Increasing data indicated that long noncoding RNAs(lncRNAs)were directly or indirectly involved in the occurrence and development of tumors,including hepatocellular carcinoma(HCC).Recent studies had found t... BACKGROUND Increasing data indicated that long noncoding RNAs(lncRNAs)were directly or indirectly involved in the occurrence and development of tumors,including hepatocellular carcinoma(HCC).Recent studies had found that the expression of lncRNA HAND2-AS1 was downregulated in HCC tissues,but its role in HCC progression is unclear.Ultrasound targeted microbubble destruction mediated gene transfection is a new method to overexpress genes.AIM To study the role of ultrasound microbubbles(UTMBs)mediated HAND2-AS1 in the progression of HCC,in order to provide a new reference for the treatment of HCC.METHODS In vitro,we transfected HAND2-AS1 siRNA into HepG2 cells by UTMBs,and detected cell proliferation,apoptosis,invasion and epithelial-mesenchymal transition(EMT)by cell counting kit-8 assay,flow cytometry,Transwell invasion assay and Western blotting,respectively.In addition,we transfected miR-837-5p mimic into UTMBs treated cells and observed the changes of cell behavior.Next,the UTMBs treated HepG2 cells were transfected together with miR-837-5p mimic and tissue inhibitor of matrix metalloproteinase-2(TIMP2)overexpression vector,and we detected cell proliferation,apoptosis,invasion and EMT.In vivo,we established a mouse model of subcutaneous transplantation of HepG2 cells and observed the effect of HAND2-AS1 silencing on tumor formation ability.RESULTS We found that UTMBs carrying HAND2-AS1 restricted cell proliferation,invasion,and EMT,encouraged apoptosis,and HAND2-AS1 silencing eliminated the effect of UTMBs.Additionally,miR-873-5p targets the gene HAND2-AS1,which also targets the 3’UTR of TIMP2.And miR-873-5p mimic counteracted the impact of HAND2-AS1.Further,miR-873-5p mimic solely or in combination with pcDNA-TIMP2 had been transformed into HepG2 cells exposed to UTMBs.We discovered that TIMP2 reversed the effect of miR-873-5p mimic caused by the blocked signalling cascade for matrix metalloproteinase(MMP)2/MMP9.In vivo results showed that HAND2-AS1 silencing significantly inhibited tumor formation in mice.CONCLUSION LncRNA HAND2-AS1 promotes TIMP2 expression by targeting miR-873-5p to inhibit HepG2 cell growth and delay HCC progression. 展开更多
关键词 Hepatocellular carcinoma Ultrasound microbubbles Long noncoding RNA HAND2-AS1 miR-873-5p Tissue inhibitor of matrix metalloproteinase-2
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A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury
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作者 Qi Liu Jianye Xie +5 位作者 Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi 《Neural Regeneration Research》 SCIE CAS 2025年第2期503-517,共15页
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv... Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury. 展开更多
关键词 angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 NEUROPROTECTION self-assembling nanofiber hydrogel
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Expression of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic stellate cells during rat hepatic fibrosis and its intervention by IL-10 被引量:35
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作者 Wei-DaZheng Li-JuanZhang Mei-NaShi Zhi-XinChen Yun-XinChen Yue-HongHuang Xiao-ZhongWang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第12期1753-1758,共6页
AIM: To investigate the expression of matrix metallopr-oteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic fibrosis and the antifibrogenic role of exogenous interleukin-10 (IL-10). METHODS: Hepatic fibro... AIM: To investigate the expression of matrix metallopr-oteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic fibrosis and the antifibrogenic role of exogenous interleukin-10 (IL-10). METHODS: Hepatic fibrosis was induced by CCI4 administration and 60 male Sprague-Dawley rats were randomly divided into normal control group (group N, 8 rats), CCI4-induced group (group C, 28 rats) and IL-10-treated group (group I, 24 rats). At the beginning of the 7th and 11th wk, rats in each group were routinely perfused with pronase E and type IV collagenase through portal vein catheter and the suspension was centrifuged by 11% Nycodenz density gradient to isolate hepatic stellate cells (HSCs). RT-PCR was used to analyze mRNA of MMP-2 and TIMP-1 from freshly isolated cells. Densitometric data were standardized with β-actin signals. Immunocytochemistry was performed to detect MMP-2 and TIMP-1 expression in HSC cultured for 72 h. RESULTS: Compared to group N in the 7th wk, MMP-2 and TIMP-1 mRNA increased in group C (P= 0.001/0.001) and group I (P= 0.001/0.009). The level of MMP-2 and TIMP-1 mRNA in group I was significantly lower than that in group C (P= 0.001/0.001). In the 11th wk, MMP-2 mRNA in group I was still lower than that in group C (P = 0.005), but both dropped compared with that in the 7th week (P = 0.001/0.004). TIMP-1 mRNA in group I was still lower than that in group C (P= 0.001), and increased in group C (P= 0.001) while decreased in group I (P = 0.042) compared with that in the 7th wk. Same results were found by immunocytochemistry. CONCLUSION: Expression of MMP-2 and TIMP-1 is increased in hepatic fibrosis. IL-10 exhibits an antifibrogenic effect by suppressing MMP-2 and TIMP-1 expression. 展开更多
关键词 RAT Hepatic fibrosis Hepatic stellate cells INTERLEUKIN-10 matrix metalloproteinases-2 Tissue inhibitor of metalloproteinases-1
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基于手机平台的Data Matrix 2维条码识别 被引量:4
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作者 刘宁钟 尤海英 孙涵 《中国图象图形学报》 CSCD 北大核心 2010年第2期287-293,共7页
传统的条码图像采集和识别是通过工业扫描枪。近年来,随着移动增值业务和3G技术的发展,2维条码在手机设备的应用中得到飞速发展。以Data Matrix为例,研究了基于嵌入式手机设备的2维条码识别技术。首先根据Data Matrix条码的特点,给出了... 传统的条码图像采集和识别是通过工业扫描枪。近年来,随着移动增值业务和3G技术的发展,2维条码在手机设备的应用中得到飞速发展。以Data Matrix为例,研究了基于嵌入式手机设备的2维条码识别技术。首先根据Data Matrix条码的特点,给出了一种基于链码跟踪和线段检测的快速Data Matrix检测算法。接着分析了条码信号经过点扩展函数卷积后的降质模型,并利用维纳滤波对条码信号进行反模糊滤波。最后,针对透视畸变的现象,设计了一种适合于嵌入式手机设备的快速反透视算法。实验结果表明,提出的识别算法具有优秀的性能,显著提高了条码的识别率,满足了实际使用的要求。 展开更多
关键词 2维条码 手机 DATA matrix反模糊 反透视变换
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EXPRESSION OF MATRIX METALLOPROTEINASE-2 AND VASCULAR ENDOTHELIAL GROWTH FACTOR IN HUMAN GLIOMA AND THEIR RELATION TO THE INVASION OF THE TUMOR
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作者 郭世文 廉民学 +2 位作者 李涛 刘守勋 刘淼 《Journal of Pharmaceutical Analysis》 SCIE CAS 2005年第2期51-53,共3页
Objective To study the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase-2 (MMP-2) in different grade human glioma. To investigate their relation to the pathological grade and invasi... Objective To study the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase-2 (MMP-2) in different grade human glioma. To investigate their relation to the pathological grade and invasion of the tumor. Methods The expression of MMP-2 and VEGF were determined by immunohistochemical technique in 48 cases of human glioma and 10 specimens of normal brain tissue. Results The expression levels of MMP-2 and VEGF in human glioma were positively related to tumor grades (P<0.01), and their expressions in the glioma of grade Ⅲ and Ⅳ were significantly different from those in the glioma of grade Ⅰ-Ⅱand normal brain tissue (P<0.01). The expression of MMP-2 was positively correlated to that of VEGF (P<0.01). Conclusion MMP-2 and VEGF were highly expression in human glioma and were positively related to the tumor grades. The synergic interaction of MMP-2 and VEGF promoted the angiogenesis and invasion of human glioma. 展开更多
关键词 GLIOMA matrix metalloproteinases-2 vascular endothelial growth factor INVASION
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原位合成TiB_(2)颗粒增强铝基复合材料研究进展 被引量:1
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作者 刘敬福 贾婧 +3 位作者 庄伟彬 覃龙健 李菁辉 孟超 《功能材料》 CAS CSCD 北大核心 2024年第2期2063-2073,共11页
原位合成技术制备的铝基复合材料,权衡了强度和塑性间的矛盾,有望实现铝基复合材料的结构功能一体化。原位合成TiB_(2)颗粒增强铝基复合材料比刚度,比模量高,具有优异的力学性能、耐腐蚀性能、耐磨性能和抗疲劳性能,是近年来金属基复合... 原位合成技术制备的铝基复合材料,权衡了强度和塑性间的矛盾,有望实现铝基复合材料的结构功能一体化。原位合成TiB_(2)颗粒增强铝基复合材料比刚度,比模量高,具有优异的力学性能、耐腐蚀性能、耐磨性能和抗疲劳性能,是近年来金属基复合材料的研究热点之一,在汽车制造、高铁动车、航空航天和国防军事等领域具有广阔的应用前景。归纳了三种原位合成TiB_(2)颗粒增强铝基复合材料反应体系(Al-K_(2)TiF_(6)-KBF_(4)体系、Al-TiO_(2)-B_(2)O_(3)体系和Al-Ti-B体系)的特点和优势,概述了原位合成TiB_(2)颗粒对铝基体晶粒尺寸、界面结合和润湿性产生影响的研究现状,对TiB_(2)颗粒强化铝复合材料力学性能的作用机制展开了讨论,梳理总结现阶段在此领域研究过程中仍未解决的问题,展望TiB_(2)颗粒增强铝基复合材料的潜在发展空间,以期为研究和开发原位合成颗粒增强铝基复合材料提供参考。 展开更多
关键词 铝基复合材料 原位合成 TiB_(2) 反应体系 显微组织 强化机制
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铜增韧Mo_(2)BC陶瓷的力学性能和摩擦学性能
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作者 张智源 王帅 +4 位作者 逄显娟 刘娟 祝林 杜三明 张永振 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第8期2867-2878,共12页
采用快速热压反应烧结法制备高强韧Mo_(2)BC/Cu陶瓷基复合材料。研究铜含量对Mo_(2)BC/Cu复合材料的微观组织、力学性能和摩擦学性能的影响,并对其增韧机制和磨损机理进行分析。研究结果表明:Cu均匀地分散在Mo_(2)BC基体中,具有细化晶... 采用快速热压反应烧结法制备高强韧Mo_(2)BC/Cu陶瓷基复合材料。研究铜含量对Mo_(2)BC/Cu复合材料的微观组织、力学性能和摩擦学性能的影响,并对其增韧机制和磨损机理进行分析。研究结果表明:Cu均匀地分散在Mo_(2)BC基体中,具有细化晶粒的作用。Mo_(2)BC/Cu复合材料中铜可以添加的最大质量分数为7.5%。随着铜含量的增加,Mo_(2)BC/Cu复合材料的弯曲强度和断裂韧性增加。当Cu质量分数为7.5%时,复合材料的弯曲强度和断裂韧性最高,分别为625.1 MPa和7.4 MPa·m^(1/2),与Mo_(2)BC陶瓷相比,分别提高了24%和62%,其主要的增韧机制为铜的塑性变形、晶粒拔出、桥接效应和裂纹的偏转。此外,铜的添加还可以明显提高Mo_(2)BC/Cu复合材料的摩擦磨损性能。当Cu质量分数为2.5%时,复合材料的摩擦因数可低至0.36,磨损量最小,耐磨性最优,其主要的磨损机制为轻微的二体磨粒磨损和氧化磨损。 展开更多
关键词 陶瓷基复合材料 Mo_(2)BC 高强韧 摩擦磨损
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7元旋转对称2-弹性函数的构造
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作者 杜蛟 李琳 +2 位作者 赵紫薇 李月月 王天银 《通信学报》 EI CSCD 北大核心 2024年第1期194-200,共7页
基于旋转对称轨道的数对分布矩阵的性质,给出了所有7元旋转对称2-弹性函数的具体构造。结果表明,在F_(2)^(7)上有且仅有280个非线性旋转对称2-弹性函数。进一步地,对于任意的奇数k,在F_(2)^(7k)上至少有280个非线性旋转对称2-弹性函数。
关键词 密码学 旋转对称函数 弹性函数 支撑矩阵 数对分布矩阵
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白内障合并2型糖尿病患者血清ES、MMP-2、MMP-9的表达及其影响因素分析
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作者 王存波 柳旭丽 +1 位作者 杨学秋 吴爽 《中国社区医师》 2024年第26期76-78,共3页
目的:探讨白内障合并2型糖尿病患者血清血管内皮抑制素(ES)、基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)的表达及其影响因素。方法:选取2019年1月—2023年1月在昌邑市人民医院就诊的白内障患者90例作为研究对象,将白内障合并2... 目的:探讨白内障合并2型糖尿病患者血清血管内皮抑制素(ES)、基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)的表达及其影响因素。方法:选取2019年1月—2023年1月在昌邑市人民医院就诊的白内障患者90例作为研究对象,将白内障合并2型糖尿病患者48例作为试验组,白内障未合并2型糖尿病患者42例作为对照组。两组均检测血清血糖、ES、MMP-2、MMP-9水平,分析白内障合并2型糖尿病患者ES、MMP-2、MMP-9高表达的影响因素,分析白内障合并2型糖尿病患者ES水平与MMP-2、MMP-9、血糖的相关性。结果:与对照组比较,试验组空腹血糖、ES、MMP-2、MMP-9水平明显更高(P<0.05)。空腹血糖浓度是白内障合并2型糖尿病患者ES、MMP-2、MMP-9高表达的影响因素(P<0.05)。白内障合并2型糖尿病患者ES水平与MMP-2、MMP-9、空腹血糖浓度呈正相关(P<0.05)。结论:白内障合并2型糖尿病患者血清ES、MMP-2、MMP-9表达水平较高,与空腹血糖浓度有关,且血清ES水平与MMP-2、MMP-9、空腹血糖浓度呈正相关。 展开更多
关键词 血管内皮抑制素 基质金属蛋白酶-2 基质金属蛋白酶-9 白内障 2型糖尿病
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替吉奥联合奥沙利铂对老年胃癌患者胃动力相关激素及基质金属蛋白酶-2、基质金属蛋白酶-9的影响
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作者 张兰芳 陈旭 +3 位作者 蒯君 秦蕾 杨艳 常廷民 《实用临床医药杂志》 CAS 2024年第12期57-60,65,共5页
目的探讨替吉奥联合奥沙利铂对老年胃癌患者胃动力相关激素及基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)的影响。方法选取128例老年胃癌患者为研究对象,随机分成对照组(n=64)与观察组(n=64)。对照组给予替吉奥治疗,观察组给予... 目的探讨替吉奥联合奥沙利铂对老年胃癌患者胃动力相关激素及基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)的影响。方法选取128例老年胃癌患者为研究对象,随机分成对照组(n=64)与观察组(n=64)。对照组给予替吉奥治疗,观察组给予替吉奥联合奥沙利铂治疗。观察2组的胃动力相关激素[胃动素(MTL)、血管活性肠肽(VIP)]、MMP-2与MMP-9、肿瘤标志物[癌胚抗原(CEA)、糖类抗原125(CA125)、糖类抗原19-9(CA19-9)]、临床疗效以及不良反应发生情况。分析胃动力相关激素与MMP-2、MMP-9及肿瘤标记物水平的相关性。结果治疗后,2组MTL低于治疗前,VIP高于治疗前,且观察组MTL低于对照组,VIP高于对照组,差异有统计学意义(P<0.05)。治疗后,2组MMP-2、MMP-9及CEA、CA125、CA19-9低于治疗前,且观察组低于对照组,差异有统计学意义(P<0.05)。观察组总有效率为70.31%,高于对照组的53.13%,差异有统计学意义(P<0.05)。2组不良反应发生率比较,差异无统计学意义(P>0.05)。MTL与MMP-2、MMP-9、CEA、CA125、CA19-9呈负相关(P<0.05);VIP与MMP-2、MMP-9、CEA、CA125、CA19-9呈正相关(P<0.05)。结论替吉奥联合奥沙利铂治疗老年胃癌患者的效果较好,且安全性较高。MTL、VIP与MMP-2、MMP-9及CEA、CA125、CA19-9在老年胃癌患者的疾病发展中起相互关联作用。 展开更多
关键词 替吉奥 奥沙利铂 老年胃癌患者 胃动力相关激素 基质金属蛋白酶-2 基质金属蛋白酶-9
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Study on the expression of matrix metalloproteinase-2 mRNA in human gastric cancer 被引量:19
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作者 Ji F Wang WL +3 位作者 Yang ZL Li YM Huang HD Chen WD 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第5期455-457,共3页
关键词 matrix METALLOPROTEINASE-2 MRNA STOMACH ncoplasms POLYMERASE CHAIN REACTION
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EGR-1和MMP-2在早期自然流产患者中的表达及临床意义
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作者 丁书军 黄丽霞 +1 位作者 熊雪 黄宁 《实用临床医学(江西)》 CAS 2024年第1期40-42,73,共4页
目的探讨早期生长反应因子(EGR-1)和基质金属蛋白酶-2(MMP-2)在早期自然流产患者绒毛中的表达及临床意义。方法采用RT-PCR和Westernblot检测20例早期自然流产患者(流产组)和20例正常早孕人工流产(对照组)绒毛组织中EGR-1和MMP-2的表达... 目的探讨早期生长反应因子(EGR-1)和基质金属蛋白酶-2(MMP-2)在早期自然流产患者绒毛中的表达及临床意义。方法采用RT-PCR和Westernblot检测20例早期自然流产患者(流产组)和20例正常早孕人工流产(对照组)绒毛组织中EGR-1和MMP-2的表达情况。结果流产组中EGR-1、MMP-2 mRNA和蛋白水平明显低于对照组,差异有统计学意义(P<0.05)。结论EGR-1和MMP-2在早孕绒毛组织中表达异常可能参与早期妊娠失败的发生。 展开更多
关键词 早期生长反应因子-1 基质金属蛋白酶-2 自然流产
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子宫肌瘤组织中MMP-2、MLCK、VEGF及IGF-2表达及其临床意义
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作者 蔡莉娜 张庆 屈红杰 《实用癌症杂志》 2024年第2期194-196,共3页
目的分析基质金属蛋白酶-2(MMP-2)、肌球蛋白轻链激酶(MLCK)、血管内皮生长因子(VEGF)、胰岛素样生长因子-2(IGF-2)在子宫肌瘤组织内的表达及临床意义。方法选取76例子宫肌瘤患者,收集其子宫肌瘤组织及正常子宫组织,采用免疫组织化学法... 目的分析基质金属蛋白酶-2(MMP-2)、肌球蛋白轻链激酶(MLCK)、血管内皮生长因子(VEGF)、胰岛素样生长因子-2(IGF-2)在子宫肌瘤组织内的表达及临床意义。方法选取76例子宫肌瘤患者,收集其子宫肌瘤组织及正常子宫组织,采用免疫组织化学法测定MMP-2、MLCK、VEGF及IGF-2表达,统计对比两者的阳性率。结果子宫肌瘤组织中MMP-2、MLCK、VEGF及IGF-2阳性表达率分别为69.74%(53/76)、60.53%(46/76)、81.58%(62/76)、92.11%(70/76),高于正常子宫组织的15.79%(12/76)、10.53%(8/76)、17.11%(13/76)、30.26%(23/76),差异有统计学意义(P<0.05)。结论MMP-2、MLCK、VEGF及IGF-2在子宫肌瘤组织中呈异常的高表达,与疾病的发生与发展存在紧密联系。 展开更多
关键词 子宫肌瘤 基质金属蛋白酶-2 血管内皮生长因子 胰岛素样生长因子-2
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寻常型银屑病患者血清脂质运载蛋白2、基质金属蛋白酶9水平与病情及预后的相关性分析
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作者 张辉 杜凡 李燕妮 《中国医刊》 CAS 2024年第11期1229-1232,共4页
目的探讨寻常型银屑病(PV)患者血清脂质运载蛋白2(LCN2)、基质金属蛋白酶9(MMP9)水平与病情严重程度及预后的相关性。方法选取2021年1月至2022年2月于延安大学附属医院就诊的88例PV患者作为研究组,采用银屑病皮肤面积和严重指数(PASI)... 目的探讨寻常型银屑病(PV)患者血清脂质运载蛋白2(LCN2)、基质金属蛋白酶9(MMP9)水平与病情严重程度及预后的相关性。方法选取2021年1月至2022年2月于延安大学附属医院就诊的88例PV患者作为研究组,采用银屑病皮肤面积和严重指数(PASI)评分对PV患者病情进行评估,根据病情分为轻度组(n=46)、中度组(n=31)、重度组(n=11),根据治疗后6个月内的皮损消退程度分为预后良好组(n=67)、预后不良组(n=21),另选取同期于延安大学附属医院体检的年龄、性别、体重指数与研究组相匹配的健康人群88例为对照组。采用Spearman法分析PV患者PASI评分与血清LCN2、MMP9水平的相关性,采用受试者操作特征(ROC)曲线分析血清LCN2、MMP9预测PV患者预后的临床效能。结果研究组与对照组的年龄、性别、体重指数、吸烟史占比、饮酒史占比方面比较差异均无统计学意义(P>0.05)。研究组血清LCN2、MMP9水平高于对照组,差异均有统计学意义(P<0.05)。重度组患者血清LCN2、MMP9水平高于中度组和轻度组,中度组患者血清LCN2、MMP9水平高于轻度组,差异均有统计学意义(P<0.05)。经Spearman法分析结果显示,PV患者PASI评分与血清LCN2、MMP9水平均呈正相关(r=0.666、0.518,P<0.05)。预后不良组患者血清LCN2、MMP9水平均高于预后良好组,差异有统计学意义(P<0.05)。ROC曲线分析结果显示,血清LCN2、MMP9联合检测对PV患者预后的预测效能优于二者单独检测(P<0.05)。结论PV患者血清LCN2、MMP9表达水平与病情严重程度密切相关,二者联合检测对PV患者的预后状态具有较高的预测效能。 展开更多
关键词 寻常型银屑病 脂质运载蛋白2 基质金属蛋白酶9 严重程度 预后
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Correlation of RECK with Matrix Metalloproteinase-2 in Regulation of Trophoblast Invasion of Early Pregnancy 被引量:6
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作者 郭君红 邹丽 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第6期738-740,共3页
To study the role of the reversion-inducing-cysteine-rich protein with Kazal motifs (RECK) gene and matrix metalloproteinase-2 (MMP-2) in the regulation of trophoblast invasion of early pregnancy. Immunohistochemi... To study the role of the reversion-inducing-cysteine-rich protein with Kazal motifs (RECK) gene and matrix metalloproteinase-2 (MMP-2) in the regulation of trophoblast invasion of early pregnancy. Immunohistochemistry, Western blot and gelatin zymography were used to detect the RECK protein expression localization, expression level and MMP-2 activation level in the placental tissues harvested from 52 normal pregnant women (27 in the early pregnancy, 25 in the term pregnancy). Immunohistochemistry showed that RECK expression was found both in villous tissues of early pregnancy group and term pregnancy group and was mainly observed in cell membrane and cytoplasm of cytotrophoblasts and syneytiotrophoblasts. RECK expression increased with gestational time. RECK expression of early pregnancy group was significantly lower than that of term pregnancy group (P〈0.05). RECK expression was significantly lower in cellular column (CC) with invasion ability. Western blot showed that the RECK protein expression in early pregnancy group was significantly lower than that in term pregnancy (P〈0.05). The optical density values of RECK protein expression in early pregnancy group and term pregnancy group were 1.35±0.14 and 2.68±0.26, respectively, while MMP-2 activation ratio was contrary to RECK protein expression and decreased with the gestation time (P〈0.01). The MMP-2 activation ratios of early pregnancy group and term pregnancy group were 0.46±0.05 and 0.10±0.02, respectively. The expression of the tumor inhibitory gene RECK was positively related with the invasion ability of trophoblasts, while the invasion gene MMP-2 was negatively related with the ability. The interaction between RECK and MMP-2 may play an important role in the regulation of the trophoblast invasion in early pregnancy. 展开更多
关键词 RECK matrix metalloproteinase-2 PLACENTA INVASION
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