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Compactness of Fractional Calderón Type Commutators on Morrey Spaces
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作者 LI Aobo MEI Ting WEI Qi 《数学进展》 北大核心 2025年第4期858-870,共13页
In this paper,the authors study the fractional Calderon type commutator T_(Ω,α)^(A)and its maximal operator M_(Ω,α)^(A)with kernels having some kinds of Log-type Dini-condition and obtain the compactness on Morrey... In this paper,the authors study the fractional Calderon type commutator T_(Ω,α)^(A)and its maximal operator M_(Ω,α)^(A)with kernels having some kinds of Log-type Dini-condition and obtain the compactness on Morrey spaces L^(p,λ)(R^(n)). 展开更多
关键词 Calderón type commutator COMPACTNESS Log-type Dini-condition Morrey space
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Late Triassic back-arc basin of the Ganzi-Litang Ocean:constraints from SSZ-type basalt in the Litang area,Eastern Tibet
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作者 Songtao Yan Ailing Ding +5 位作者 Lidong Zhu Meng Qin Tao Liu Jie Wang Chongyang Xin Qingsong Wu 《Episodes》 2025年第3期241-254,共14页
The genesis and tectonic setting of Late Triassic volcanic rocks in the Ganzi–Litang ophiolitic mélange belt have long been a subject of contention.To elucidate these ambiguities,comprehensive petrological,geoch... The genesis and tectonic setting of Late Triassic volcanic rocks in the Ganzi–Litang ophiolitic mélange belt have long been a subject of contention.To elucidate these ambiguities,comprehensive petrological,geochemical,zircon U-Pb geochronological,and Sr-Nd isotopic analyses were conducted on the Luexigou basalts in the Litang area.This investigation has newly delineated a typical volcano-sedimentary sequence indicative of a mid-ocean ridge,with basalts dated to 215±3 Ma.These basalts exhibit geochemical characteristics akin to E-MORB,displaying relatively flat distribution patterns for rare earth elements and trace elements.They are notably depleted in high-field-strength elements(such as Nb and Ta),similar to volcanic arc basalts. 展开更多
关键词 ophiolitic m lange belt back arc basin Late Triassic Litang area late triassic volcanic rocks SSZ type basalt geochemical chara Ganzi Litang Ocean
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无线mesh网络B.A.T.M.A.N.adv路由协议的分析与优化 被引量:2
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作者 申爽 李绍文 罗军 《微计算机信息》 2012年第10期327-329,363,共4页
本文首先根据对B.A.T.M.A.N.adv路由协议的工作原理和结构功能分析,首次提出了一种针对于B.A.T.M.A.N.adv路由协议滑动窗口保护机制的优化方案,然后通过使用iperf工具和B.A.T.M.A.N.adv提供的2层网络工具包batctl,重点测试了吞吐量、丢... 本文首先根据对B.A.T.M.A.N.adv路由协议的工作原理和结构功能分析,首次提出了一种针对于B.A.T.M.A.N.adv路由协议滑动窗口保护机制的优化方案,然后通过使用iperf工具和B.A.T.M.A.N.adv提供的2层网络工具包batctl,重点测试了吞吐量、丢包率,和往返时延等路由性能参数。验证了该优化方案的正确性。 展开更多
关键词 无线MESH网络 B A T M A N ADV 协议优化 LINUX
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基于费用优化的排队服务系统的最优控制策略分析
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作者 佘启月 唐应辉 余玅妙 《应用数学》 北大核心 2026年第1期209-220,共12页
基于样品检测系统背景,本文考虑一个具有服务启动(p,N)-策略和双阈值(m,N)-策略的M/G/1排队服务系统,我们首先求得稳态队长的概率母函数、平均队长和顾客平均等待时间的表达式.其次,我们把检测系统检验样品过程用排队服务过程刻画,建立... 基于样品检测系统背景,本文考虑一个具有服务启动(p,N)-策略和双阈值(m,N)-策略的M/G/1排队服务系统,我们首先求得稳态队长的概率母函数、平均队长和顾客平均等待时间的表达式.其次,我们把检测系统检验样品过程用排队服务过程刻画,建立系统的费用结构模型和费用目标函数,从经济效益的角度出发讨论了系统的费用优化与最优控制策略,在没有平均等待时间和有平均等待时间约束下,通过数值计算实验确定了使得系统期望费用最小的最优控制策略(m^(*),N^(*)),并讨论了参数p、m、N对系统的空闲率和附加平均队长的影响,同时也分析了参数p对费用优化和最优控制策略的影响. 展开更多
关键词 服务启动(p N)-策略 双阈值(m N)-策略 M/G/1排队 费用优化 最优控制策略
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利妥昔单抗治疗M型磷脂酶A2受体相关特发性膜性肾病的疗效及预后分析
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作者 张凯博 李粲 孔凡武 《中国现代药物应用》 2026年第2期95-98,共4页
目的分析M型磷脂酶A2受体相关特发性膜性肾病运用利妥昔单抗治疗的效果及预后。方法39例M型磷脂酶A2受体相关特发性膜性肾病患者,均运用利妥昔单抗治疗。分析患者的临床疗效以及不良反应发生情况,比较不同时间点实验室指标(24 h尿蛋白... 目的分析M型磷脂酶A2受体相关特发性膜性肾病运用利妥昔单抗治疗的效果及预后。方法39例M型磷脂酶A2受体相关特发性膜性肾病患者,均运用利妥昔单抗治疗。分析患者的临床疗效以及不良反应发生情况,比较不同时间点实验室指标(24 h尿蛋白定量、血肌酐、白蛋白、甘油三酯、免疫球蛋白G)。结果经过12个月随诊,39例患者完全缓解22例、占比56.41%,部分缓解15例、占比38.46%,未缓解2例、占比5.13%;总有效率为94.87%。经过12个月随诊,39例患者出现恶心1例,占比2.56%;呕吐1例,占比2.56%;肝功能异常0例;感染1例,占比2.56%;血糖升高0例。不良反应总发生率为7.69%。治疗后1、3、6、12个月的24 h尿蛋白定量、血肌酐、甘油三酯均较治疗前降低,白蛋白较治疗前升高,治疗后12个月的免疫球蛋白G水平较治疗前升高,有差异(P<0.05)。结论对M型磷脂酶A2受体相关特发性膜性肾病患者运用利妥昔单抗治疗的效果显著,可有效改善实验室相关指标,值得临床推荐。 展开更多
关键词 利妥昔单抗 M型磷脂酶A2受体 特发性膜性肾病 肾功能
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PREDIM对2型糖尿病微血管病的预测价值
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作者 朱小兰 刘欣仪 +2 位作者 王文佳 霍昕涛 张红灵 《中西医结合心脑血管病杂志》 2026年第2期265-271,共7页
目的:收集2型糖尿病病人临床数据,分析合并糖尿病微血管病的危险因素,分析新型胰岛素敏感度指标PREDIcted M(PREDIM)对糖尿病微血管病(DM)的预测价值。方法:选取2021年1月—2023年12月山西医科大学第一医院就诊的200例2型糖尿病病人,收... 目的:收集2型糖尿病病人临床数据,分析合并糖尿病微血管病的危险因素,分析新型胰岛素敏感度指标PREDIcted M(PREDIM)对糖尿病微血管病(DM)的预测价值。方法:选取2021年1月—2023年12月山西医科大学第一医院就诊的200例2型糖尿病病人,收集病人临床资料,计算甘油三酯-葡萄糖指数(TyG)和PREDIM。根据是否合并微血管病并发症分为微血管病组(DM组)和无微血管病组(NDM组),评价PREDIM的预测价值。结果:DM组和NDM组性别、病程、合并高血压、空腹血糖、糖化血红蛋白(HbA1c)、尿白蛋白、尿白蛋白/肌酐、三酰甘油、TyG、PREDIM比较,差异均有统计学意义(P<0.05)。单因素回归分析显示,病程、高血压、空腹血糖、空腹胰岛素、HbA1c、尿白蛋白、尿白蛋白/肌酐、三酰甘油、TyG、PREDIM为DM的影响因素。多因素Logistic回归分析显示:病程、尿白蛋白/肌酐、HbA1c、三酰甘油、降低的PREDIM为DM的独立危险因素。TyG预测2型糖尿病发生DM的受试者工作特征(ROC)曲线下面积(AUC)为0.689,95%CI[0.604,0.773],敏感度为66.7%,特异度为65.9%,最佳临界值为9.132。PREDIM预测2型糖尿病发生DM的AUC为0.738,95%CI[0.654,0.822],敏感度为42.1%,特异度为97.6%,最佳临界值为4.392。TyG+病程预测2型糖尿病发生DM的AUC为0.728,95%CI[0.647,0.809],敏感度为63.2%,特异度为76.4%。PREDIM+病程联合预测2型糖尿病发生DM的AUC为0.781,95%CI[0.700,0.864],敏感度为68.4%,特异度为81.3%。结论:PREDIM是发生DM的保护因素,每升高1个单位,风险降低36%;PREDIM对DM有较高的预测价值,且优于TyG;PREDIM<4.392时,2型糖尿病病人发生DM的风险提高;PREDIM联合糖尿病病程诊断价值显著提高。 展开更多
关键词 2型糖尿病 糖尿病微血管病 胰岛素抵抗 甘油三酯-葡萄糖指数 PREDIcted M
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miR-1246调控METTL3介导的m^(6)A修饰对高糖诱导的视网膜微血管内皮细胞损伤的影响
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作者 周米露 陈琳 +1 位作者 赵佐芳 王大庆 《国际眼科杂志》 2026年第1期7-15,共9页
目的:探究miR-1246调控甲基转移酶样3(METTL3)介导的沉默信息调节因子1(SIRT1)N^(6)-甲基腺苷(m^(6)A)修饰对高糖诱导的视网膜微血管内皮细胞(RMECs)损伤的影响。方法:双荧光素酶实验检测miR-1246调控METTL3表达;RMECs细胞分为对照组、... 目的:探究miR-1246调控甲基转移酶样3(METTL3)介导的沉默信息调节因子1(SIRT1)N^(6)-甲基腺苷(m^(6)A)修饰对高糖诱导的视网膜微血管内皮细胞(RMECs)损伤的影响。方法:双荧光素酶实验检测miR-1246调控METTL3表达;RMECs细胞分为对照组、模型(HG)组、高糖+敲低对照(HG+anti-miR-NC)组、高糖+敲低miR-1246表达(HG+anti-miR-1246)组、高糖+过表达对照(HG+NC)组、高糖+过表达METTL3(HG+METTL3)组、高糖+过表达miR-1246+对照(HG+miR-1246+NC)组、高糖+过表达miR-1246+METTL3(HG+miR-1246+METTL3)组。经过高糖诱导48 h后,CCK-8法检测细胞存活;Annexin V-FITC/PI法检测细胞凋亡;Transwell实验检测细胞迁移和侵袭;ELISA法检测细胞氧化应激和炎症水平;比色法检测总RNA中m^(6)A甲基化水平;MeRIP-qPCR法检测SIRT1 m^(6)A甲基化水平;实时荧光定量PCR检测细胞miR-1246、METTL3、SIRT1 mRNA表达;Western blot检测细胞METTL3、SIRT1及内皮-间充质转化(EndMT)标志物蛋白表达。结果:miR-1246调控METTL3表达。与对照组比较,HG组细胞存活率降低,凋亡率升高,迁移和侵袭细胞数增加,细胞培养上清液乳酸脱氢酶(LDH)活性、肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6水平升高,IL-10水平降低,细胞丙二醛(MDA)水平升高,超氧化物歧化酶(SOD)活性降低,细胞miR-1246表达升高,总RNA m^(6)A水平和SIRT1 m^(6)A水平降低,METTL3、SIRT1、分化群抗原31(CD31)、血管内皮钙黏蛋白(VE-cadherin)表达降低,波形蛋白(Vimentin)、Snail同源物1(Snail1)表达升高(均P<0.05);与HG+anti-miR-NC组比较,HG+anti-miR-1246组细胞存活率升高,凋亡率降低,迁移和侵袭细胞数减少,细胞培养上清液LDH活性、TNF-α、IL-6水平降低,IL-10水平升高,细胞MDA水平降低,SOD活性升高,细胞miR-1246表达降低,总RNA m^(6)A水平和SIRT1 mRNA m^(6)A水平升高,METTL3、SIRT1、CD31、VE-cadherin表达升高,Vimentin、Snail1表达降低(均P<0.05);与HG+NC组比较,HG+METTL3组细胞存活率升高,凋亡率降低,迁移和侵袭细胞数减少,细胞培养上清液LDH活性、TNF-α、IL-6水平降低,IL-10水平升高,细胞MDA水平降低,SOD活性升高,细胞miR-1246表达降低,总RNA m^(6)A水平和SIRT1 mRNA m^(6)A水平升高,METTL3、SIRT1、CD31、VE-cadherin表达升高,Vimentin、Snail1表达降低(均P<0.05);与HG+miR-1246+NC组比较,HG+miR-1246+METTL3组细胞存活率升高,凋亡率降低,迁移和侵袭细胞数减少,细胞培养上清液LDH活性、TNF-α、IL-6水平降低,IL-10水平升高,细胞MDA水平降低,SOD活性升高,细胞miR-1246表达降低,总RNA m^(6)A水平和SIRT1 mRNA m^(6)A水平升高,METTL3、SIRT1、CD31、VE-cadherin表达升高,Vimentin、Snail1表达降低(均P<0.05)。结论:miR-1246通过调控METTL3介导的SIRT1 m^(6)A修饰,促进高糖诱导的RMECs细胞凋亡、侵袭转移、氧化应激、炎症反应及EndMT过程。 展开更多
关键词 miR-1246 视网膜微血管内皮细胞 糖尿病视网膜病变 甲基转移酶样3(METTL3) 沉默信息调节因子1 N^(6)-甲基腺苷(m^(6)A)修饰
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糖皮质激素性骨质疏松症发病机制及诊治进展
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作者 高增杰 李来来 +5 位作者 柴艺汇 黄华 覃裕 袁云飞 王璐 蒋玥玥 《颈腰痛杂志》 2026年第1期143-149,共7页
糖皮质激素性骨质疏松症(GIOP)是临床最常见的继发性骨质疏松症,临床危害极大。本研究通过查阅国内外文献和研究进展,梳理并汇总分析GIOP的发病机制、治疗争议和难点,发现糖皮质激素主要通过抑制骨形成、促进骨吸收、降低肠道钙吸收、... 糖皮质激素性骨质疏松症(GIOP)是临床最常见的继发性骨质疏松症,临床危害极大。本研究通过查阅国内外文献和研究进展,梳理并汇总分析GIOP的发病机制、治疗争议和难点,发现糖皮质激素主要通过抑制骨形成、促进骨吸收、降低肠道钙吸收、扰乱成骨成脂分化、弱化骨矿化等途径造成骨质疏松。主要的信号通路和靶点涉及RANK/RANKL/OPG系统、Wnt/β-catenin信号通路、性激素及生长因子调控、肠道菌群及PPARγ2/KLF15通路;会导致骨转换标志物Ⅰ型前胶原氨基端前肽(PINP)水平下降,β-Ⅰ型胶原交联羧基端肽片段(β-CTX)水平升高。治疗难点在于临床获益和风险的平衡、监测标准、治疗药物不统一,患者依从性差、失访、慢病管理难度大等导致疗效波动。本研究将为临床和科研探索、控制GIOP提供参考。 展开更多
关键词 糖皮质激素性骨质疏松症 骨质疏松症 骨代谢 骨标志物 破骨细胞 成骨细胞 Ⅰ型前胶原氨基端前肽 骨折风险
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关于Smarandache-Type可乘函数的均值
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作者 王明军 《甘肃科学学报》 2011年第4期9-11,共3页
研究了Smarandache-Type可乘函数Fm(n)与Gm(n)在无m次幂因子数集上的均值分布性质,利用解析方法及欧拉乘积公式得到了2个渐近公式,从而推广了关于Smarandache-Type可乘函数的算术性质.
关键词 Smarandache-type可乘函数 无m次幂因子数 渐近公式
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具有S-N弱鞅差序列的Hájek-Rényi型不等式及强大数定律
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作者 冯德成 贾晓敏 《西北师范大学学报(自然科学版)》 2026年第1期131-134,共4页
给出了具有S-N弱鞅差随机变量序列的Kolmogorov型不等式和Hájek-Rényi型不等式,以此为基础,得到了具有S-N弱鞅差随机变量序列的强大数定律.
关键词 S-N弱鞅差序列 Kolmogorov型不等式 Hájek-Rényi型不等式 强大数定律
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Effects of Primary Carbide Size and Type on the Sliding Wear and Rolling Contact Fatigue Properties of M50 Bearing Steel 被引量:4
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作者 Liqi Yang Weihai Xue +5 位作者 Siyang Gao Yanfei Cao Hongwei Liu Deli Duan Dianzhong Li Shu Li 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2023年第8期1336-1352,共17页
The influences of primary carbide size and type on the sliding wear behavior and rolling contact fatigue (RCF) properties of M50 bearing steel were systematically investigated under oil lubrication condition. A major ... The influences of primary carbide size and type on the sliding wear behavior and rolling contact fatigue (RCF) properties of M50 bearing steel were systematically investigated under oil lubrication condition. A major breakthrough was achieved in the influence of primary carbide on tribological behavior. The opposite effect brought by primary carbide size on the sliding wear resistance and RCF life of M50 bearing steel was determined. Wear resistance increased with an increase in the studied primary carbide size, whereas RCF life decreased significantly. Compared with the 0 R and R positions with a relatively small carbide size, the wear volume of the 1/2 R position with a large carbide size was the smallest. Compared with the 0 R and R positions, the L10 life of the 1/2 R position decreased by 82.7% and 84.8%, respectively. On the basis of the statistical correlation between primary carbide size and the two tribological properties, a critical maximum carbide size of 5-10 μm was proposed to achieve optimal tribological performance. This research suggests that the equivalent diameter of the primary carbide should be controlled to be smaller than 10 μm, but further decreasing primary carbide size to less than 5 μm is unnecessary. The influence of primary carbide type in M50 bearing steel on sliding wear resistance was also discussed. Results indicate that the MC-type carbides with higher elastic modulus and microhardness exhibit better wear resistance than the M2C-type carbides. 展开更多
关键词 Carbide size Carbide type Sliding wear Rolling contact fatigue M50 bearing steel
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Antiviral activity of Basidiomycete mycelia against influenza type A(serotype H1N1) and herpes simplex virus type 2 in cell culture 被引量:5
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作者 Tetiana Krupodorova Svetlana Rybalko Victor Barshteyn 《Virologica Sinica》 SCIE CAS CSCD 2014年第5期284-290,共7页
In this study, we investigated the in vitro antiviral activity of the mycelia of higher mushrooms against influenza virus type A(serotype H1N1) and herpes simplex virus type 2(HSV-2), strain BH. All 10 investigated mu... In this study, we investigated the in vitro antiviral activity of the mycelia of higher mushrooms against influenza virus type A(serotype H1N1) and herpes simplex virus type 2(HSV-2), strain BH. All 10 investigated mushroom species inhibited the reproduction of influenza virus strain A/FM/1/47(H1N1) in MDCK cells reducing the infectious titer by 2.0–6.0 lg ID50. Four species, Pleurotus ostreatus, Fomes fomentarius, Auriporia aurea, and Trametes versicolor, were also determined to be effective against HSV-2 strain BH in RK-13 cells, with similar levels of inhibition as for influenza. For some of the investigated mushroom species—Pleurotus eryngii, Lyophyllum shimeji, and Flammulina velutipes—this is the first report of an anti-influenza effect. This study also reports the first data on the medicinal properties of A. aurea, including anti-influenza and antiherpetic activities. T. versicolor 353 mycelium was found to have a high therapeutic index(324.67), and may be a promising material for the pharmaceutical industry as an anti-influenza and antiherpetic agent with low toxicity. Mycelia with antiviral activity were obtained in our investigation by bioconversion of agricultural wastes(amaranth flour after CO2 extraction), which would reduce the cost of the final product and solve some ecological problems. 展开更多
关键词 antiviral activity Basidiomycetes mycelium INFLUENZA A virus(H1N1) herpes simplex VIRUS type 2(HSV2)
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Nonsingularity on Level-2(r_1, r_2)-circulant Matrices of Type (m,n) 被引量:5
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作者 江兆林 郭运端 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第2期106-110,共5页
In this pape,we give four methods of discriminations its nonsingularity by utilizing only parametr r1,r2 and elements of the first row of level-2 (r1, r2)-circulant matrices of type (m,n).
关键词 level-2(r_1 r_2)-circulant matrices of type (m n) nonsingularit
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Stratifying the risk of lymph node metastasis in undifferentiated-type early gastric cancer 被引量:11
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作者 Yukiko Asakawa Masahiko Ohtaka +28 位作者 Shinya Maekawa Mitsuharu Fukasawa Yasuhiro Nakayama Tatsuya Yamaguchi Taisuke Inoue Tomoyoshi Uetake Minoru Sakamoto Tadashi Sato Yoshihiko Kawaguchi Hideki Fujii Kunio Mochizuki Masao Hada Toshio Oyama Tomotaka Yasumura Kosaku Omata Atsushi Nishiyama Keiichi Naito Hideo Hata Yoshiaki Haba Kazuyuki Miyata Haruhisa Saitoh Yoichi Yamadera Kazuo Miura Akira Kawaoi Tohru Abe Hajime Tsunoda Yuji Honda Masayuki Kurosaki Nobuyuki Enomoto 《World Journal of Gastroenterology》 SCIE CAS 2015年第9期2683-2692,共10页
AIM:To study how lymph node metastasis(LNM) risk is stratified in undifferentiated-type early gastric cancer(undiff-EGC) dependent on combinations of risk factors.METHODS:Five hundred and sixty-seven cases with undiff... AIM:To study how lymph node metastasis(LNM) risk is stratified in undifferentiated-type early gastric cancer(undiff-EGC) dependent on combinations of risk factors.METHODS:Five hundred and sixty-seven cases with undiff-EGC undergoing gastrectomy with lymphadenectomy were examined retrospectively.Using clinicopathological factors of patient age,location,size,an endoscopic macroscopic tumor form,ulceration,depth,histology,lymphatic involvement(LI) and venous involvement(VI),LNM risk was examined and stratified by conventional statistical analysis and datamining analysis.RESULTS:LNM was positive in 44 of 567 cases(7.8%).Univariate analysis revealed > 2 cm,protrusion,submucosal(sm),mixed type,LI and VI as significant prognostic factors and > 2 cm and LI-positive were independent factors by multivariate analysis.In preoperatively evaluable factors excluding LVI,sm and > 2 cm were independent factors.According to the depth and size,cases were categorized into the low-risk group [m and ≤ 2 cm,0%(LNM incidence)],the moderaterisk group(m and > 2 cm,5.6%; and sm and ≤ 2 cm,6.0%),and the high-risk group(sm and > 2 cm,19.3%).On the other hand,LNM occurred in 1.4% in all LI-negative cases,greatly lower than 28.2% in all LI-positive cases,and LNM incidence was low in LInegative cases even in the moderate- and high-risk groups.CONCLUSION:LNM-related factors in undiff-EGC were depth and size preoperatively while those were LI and size postoperatively.Among these factors,LI was the most significantly correlated factor. 展开更多
关键词 Undifferentiated-type EARLY GASTRIC cancer LYMPH n
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Faecal pyruvate kinase isoenzyme type M2 for colorectal cancer screening:A meta-analysis 被引量:19
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作者 Carolin Tonus Markus Sellinger +1 位作者 Konrad Koss Gero Neupert 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第30期4004-4011,共8页
AIM:To present a critical discussion of the efficacy of the faecal pyruvate kinase isoenzyme type M2(faecal M2-PK) test for colorectal cancer(CRC) screening based on the currently available studies.METHODS:A literatur... AIM:To present a critical discussion of the efficacy of the faecal pyruvate kinase isoenzyme type M2(faecal M2-PK) test for colorectal cancer(CRC) screening based on the currently available studies.METHODS:A literature search in PubMed and Embase was conducted using the following search terms:fecal Tumor M2-PK,faecal Tumour M2-PK,fecal M2-PK,faecal M2-PK,fecal pyruvate kinase,faecal pyruvate kinase,pyruvate kinase stool and M2-PK stool.RESULTS:Stool samples from 704 patients with CRC and from 11 412 healthy subjects have been investigated for faecal M2-PK concentrations in seventeen independent studies.The mean faecal M2-PK sensitivity was 80.3%;the specificity was 95.2%.Four studies compared faecal M2-PK head-to-head with guaiacbased faecal occult blood test(gFOBT).Faecal M2PK demonstrated a sensitivity of 81.1%,whereas the gFOBT detected only 36.9% of the CRCs.Eight independent studies investigated the sensitivity of faecal M2-PK for adenoma(n = 554),with the following sensitivities:adenoma < 1 cm in diameter:25%;adenoma > 1 cm:44%;adenoma of unspecified diameter:51%.In a direct comparison with gFOBT of adenoma > 1 cm in diameter,47% tested positive with the faecal M2-PK test,whereas the gFOBT detected only 27%.CONCLUSION:We recommend faecal M2-PK as a routine test for CRC screening.Faecal M2-PK closes a gap in clinical practice because it detects bleeding and nonbleeding tumors and adenoma with high sensitivity and specificity. 展开更多
关键词 Faecal pyruvate kinase isoenzyme type M2 Colorectal cancer screening Colorectal cancer Stool Faecal occult blood Adenoma Polyps
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The Explicit Expressions of Level-k Circulant Matrices of Type(n_1,n_2.…,n_k) and Their Some Properties 被引量:2
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作者 江兆林 郭运瑞 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第3期103-110,共8页
In this paper, we give the explicit expressions of level-k circulant matrices of type (n1,n2,…nk) and of order n1n2…nk,and the explicit expressions for the eigenvalues,the determinants and the inverse matrices of th... In this paper, we give the explicit expressions of level-k circulant matrices of type (n1,n2,…nk) and of order n1n2…nk,and the explicit expressions for the eigenvalues,the determinants and the inverse matrices of the kind level-k circulant matrices are derived,and it is also proved that the sort matrices are unitarily diagonalizable. 展开更多
关键词 level-k circulant matrices of type (n1 n2 nk) explicit expressions eigenvalues determinants inverse matrices unitarily diagonalizable
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GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N) 被引量:2
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作者 Xuejun ZHANG Yuting GUO +1 位作者 Hongxin CHEN Pengcheng TANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1301-1326,共26页
In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t... In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals. 展开更多
关键词 Forelli-Rudin type operator L^(p q s k)(B_(n))space BOUNDEDNESS unit ball
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Influence of La-Co substitution on the structure and magnetic properties of low-temperature sintered M-type barium ferrites 被引量:4
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作者 李颉 张怀武 +2 位作者 李强 李元勋 郁国良 《Journal of Rare Earths》 SCIE EI CAS CSCD 2013年第10期983-987,共5页
La-Co substituted M-type barium ferrites (BaM) were prepared by traditional solid state method and sintered at low tem- perature (1173 K). X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrat... La-Co substituted M-type barium ferrites (BaM) were prepared by traditional solid state method and sintered at low tem- perature (1173 K). X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM) were employed to investigate the influence of La-Co on the structure and magnetic properties of the samples. By sintering at 1173 K for 6 h in air, single phase M-type barium ferrites with chemical composition of Ba(LaCo)xFel〉z^Oj9 (x=0.0~).5) were formed. M-H curves showed that the magnetic properties of barium ferrites were obviously effected by La-Co substitution. The saturation magnetization (Ms) and coercivity (He) reached the maximum value of 65.15 AmZ/kg and 4165 Oe, respectively. This behavior was attributed to the sites of La-Co substitutions and the particles size. SEM revealed that the shape of ferrite particles was influenced by La-Co substitution. 展开更多
关键词 M-type barium fenites La-Co substitution magnetic properties rare earths
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Magnetic properties of M-type strontium ferrites with different heat treatment conditions 被引量:2
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作者 Namji Oh Seungyeon Park +3 位作者 Yongwan Kim Hyukmin Kwon Sangsub Kim Kyoungmook Lim 《Rare Metals》 SCIE EI CAS CSCD 2020年第1期84-88,共5页
The effects of heat treatment conditions on the magnetic properties and microstructure of M-type strontium ferrite according to calcination temperature were analyzed.Strontium ferrite Sr0.06Ca0.52La0.52Fe11.68Co0.22O1... The effects of heat treatment conditions on the magnetic properties and microstructure of M-type strontium ferrite according to calcination temperature were analyzed.Strontium ferrite Sr0.06Ca0.52La0.52Fe11.68Co0.22O19magnetic powder was prepared by a standard ceramic process.During experiments,the calcination temperature was varied from 1180 to 1260℃,and sintering temperature was fixed.While the M-phase(SrFe12O19)existed with hematite(Fe2 O3)in the powder calcined at below 1220℃,the pure M-phase was observed in the powder calcined at over1240℃.With an increase in the calcination temperature,the magnetization of the calcined powder increases,meanwhile,the coercivity decreases.The magnetization is improved by decreasing the lattice constant c and activating the Fe3+-OFe3+superexchange interaction,and the coercivity decreases by the large particle sizes due to the grain growth. 展开更多
关键词 M-type ferrites Standard CERAMIC process Phase analysis SUPEREXCHANGE PERMANENT MAGNET
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Low temperature sintering behavior of La-Co substituted M-type strontium hexaferrites for use in microwave LTCC technology 被引量:4
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作者 黄太星 彭龙 +3 位作者 李乐中 王瑞 胡云 涂小强 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第2期148-151,共4页
The La-Co substituted Sr1–xLaxFe12–xCoxO19 (x=0–0.5) ferrites with appropriate Bi2O3 additive were prepared by conventional sintering method and microwave sintering method at low sintering temperatures compatible w... The La-Co substituted Sr1–xLaxFe12–xCoxO19 (x=0–0.5) ferrites with appropriate Bi2O3 additive were prepared by conventional sintering method and microwave sintering method at low sintering temperatures compatible with LTCC (low temperature co-fired ceramics) systems, and their sintering behavior was chiefly investigated, including the crystal structure, saturation magnetizationMs, magnetic anisotropy fieldHa, intrinsic coercivityHci, and Curie temperatureTC. Experiment results clearly showed that the pure M-type crystal phase was successfully obtained when the La-Co substitution amountx did not exceed 0.3. However, the single M-type phase structure transformed to multiphase structure with further increased x, where the M-type phase coexisted with the non-magnetic phase such asα-Fe2O3 phase, La2O3 phase, and LaCoO3 phase. Appropriate La-Co substitution improved theMs (>62 emu/g),Ha (>1400 kA/m), andHci (>320 kA/m) for the ferrites withx varying from 0.1 to 0.3, but theTC decreased with increasing substitution amount. More-over, the microwave sintered ferrites could provide largerHci and similarMs compared with the conventional sintered ferrites. 展开更多
关键词 M-type hexaferrites SrFe12O19 ferrites La-Co substitution low temperature sintering LTCC rare earths
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