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基于FTO调控Notch1通路观察阳和平喘颗粒对哮喘BMSC归巢的影响
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作者 王坤 方昊翔 曹晓梅 《细胞与分子免疫学杂志》 北大核心 2025年第7期585-592,共8页
目的观察N^(6)甲基腺嘌呤(m^(6)A)甲基化调控缺刻基因1(Notch1)通路对哮喘骨髓间充质干细胞(BMSC)归巢的影响,以及中药复方阳和平喘颗粒干预研究。方法采用大鼠BMSC和支气管上皮细胞共培养的方式。将提取的细胞分为支气管上皮细胞组、... 目的观察N^(6)甲基腺嘌呤(m^(6)A)甲基化调控缺刻基因1(Notch1)通路对哮喘骨髓间充质干细胞(BMSC)归巢的影响,以及中药复方阳和平喘颗粒干预研究。方法采用大鼠BMSC和支气管上皮细胞共培养的方式。将提取的细胞分为支气管上皮细胞组、哮喘支气管上皮细胞联合间充质干细胞共培养组(以下简称共培养组)、共培养细胞联合正常血清组、共培养细胞联合最佳含药血清组、siRNA-FTO联合正常血清组、siRNA-FTO-NC联合正常血清组、siRNA-FTO联合最佳含药血清组。检测共培养细胞活力和细胞周期变化;免疫荧光染色法检测BMSC归巢水平和归巢标志物;实时定量PCR检测Notch1通路相关基因的表达;Western blot法检测Notch1通路相关蛋白的表达。结果与支气管上皮细胞组比较,共培养细胞组BMSC归巢水平和趋化因子受体4(CXCR4)、人基质细胞衍生因子1(SDF-1)、Notch1、重组信号结合蛋白J(RBP-J)、发状分裂相关增强子1(Hes1)蛋白表达升高。与共培养细胞组、共培养细胞联合正常血清组比较,共培养细胞联合最佳含药血清组BMSC归巢水平及CXCR4、SDF-1表达升高,Notch1、Hes1蛋白mRNA表达降低。与siRNA-FTO-NC联合正常血清组比较,siRNA-FTO联合正常血清组Notch1、Activated Notch1、RBP-J、Hes1蛋白表达和细胞活力升高,BMSC归巢水平降低。与siRNA-FTO联合正常血清组比较,siRNA-FTO联合最佳含药血清组Notch1、RBP-J mRNA,Activated Notch1、Hes1蛋白表达降低,BMSC归巢水平升高,共培养细胞联合最佳含药血清组Notch1、RBP-J、Hes1 mRNA表达降低。与siRNA-FTO联合最佳含药血清组比较,共培养细胞联合最佳含药血清组细胞活力及Notch1、Activated Notch1、RBP-J、Hes1蛋白降低,BMSC归巢水平升高。结论阳和平喘颗粒可能通过上调FTO表达,抑制下游Notch1信号通路表达,从而促进哮喘BMSC归巢,减轻哮喘炎症。 展开更多
关键词 骨髓间充质干细胞(BmSC) 支气管哮喘 n^(6)甲基腺嘌呤(m^(6)A) notch1信号通路
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基于可变服务率M/M/c/N部分可修排队模型的银行服务窗口数优化设计
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作者 赵佳宜 李建军 刘力维 《应用数学》 北大核心 2025年第3期796-805,共10页
本文提出一种带有可变服务率的M/M/c/N排队模型,用于对银行服务系统进行建模,该模型考虑了顾客的不耐烦行为及部分服务台的不可靠性.用马尔可夫过程理论建立了系统稳态平衡方程,运用矩阵几何解方法对其求解,获得了系统的平均队长、顾客... 本文提出一种带有可变服务率的M/M/c/N排队模型,用于对银行服务系统进行建模,该模型考虑了顾客的不耐烦行为及部分服务台的不可靠性.用马尔可夫过程理论建立了系统稳态平衡方程,运用矩阵几何解方法对其求解,获得了系统的平均队长、顾客的总损失率等稳态性能特征.基于系统稳态性能特征,建立了以银行效益最大为目标的优化模型,以此来确定银行的最佳窗口数,并通过数字算例对优化模型进行了说明.本文的研究为银行提升服务质量和资源优化配置提供了一定的理论参考. 展开更多
关键词 可变服务率 m/m/c/n 不耐烦行为 不可靠性
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四元数环上的(m,n)-Jordan中心化子和(m,n)-Lie中心化子
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作者 连佳欣 张建华 孔亮 《吉林大学学报(理学版)》 北大核心 2025年第6期1615-1621,共7页
设S是环,H(S)是S上的四元数环.考虑四元数环上的(m,n)-Jordan中心化子和(m,n)-Lie中心化子,利用生成元分析法证明(m,n)-Jordan中心化子是标准的中心化子,(m,n)-Lie中心化子是标准的Lie中心化子.
关键词 四元数环 (m n)-Jordan中心化子 (m n)-Lie中心化子
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宫颈癌TNM分期与预后相关性分析 被引量:1
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作者 陈锦元 蒋祎 《世界肿瘤研究》 2025年第1期45-51,共7页
目的:基于SEER数据库的宫颈癌患者影响因素分析,分析影响宫颈癌预后的相关因素,为宫颈癌患者预后恢复及治疗提供科学参考依据。方法:利用SEER数据库初步筛查宫颈癌相关数据,从中下载所有符合研究的宫颈癌患者的不同病理分型的数据,选用... 目的:基于SEER数据库的宫颈癌患者影响因素分析,分析影响宫颈癌预后的相关因素,为宫颈癌患者预后恢复及治疗提供科学参考依据。方法:利用SEER数据库初步筛查宫颈癌相关数据,从中下载所有符合研究的宫颈癌患者的不同病理分型的数据,选用第八期T,N,M分期对数据的T,N,M分期进行整理,标准化,筛选,筛选条件为患者第八期T,N,M分期明确,有符合要求的观察结局,如死亡或存活。通过筛查出的患者的不同病理分型的数据,运用SPSS26.0统计软件进行统计描述,采用Kaplan-Meier法。描绘生存曲线并估计患者的生存率,死亡率。生存时间分布的组间比较采用Log-Rank检验,对分析结果中P α = 0.05,以P Objective: Study on the prognostic risk model of cervical cancer patients based on SEER database, analyze the relevant factors affecting the prognosis of cervical cancer, and provide scientific reference for the prognosis recovery and treatment of cervical cancer patients. Methods: The SEER database was used to preliminarily screen the data related to cervical cancer, download the data of different pathological types of cervical cancer patients in line with the study, and select the eighth stage T, N, M to sort out, standardize and screen the T, N and M stages of the data. The screening conditions were that the eighth stage T, N and M stages of patients were clear, and there were satisfactory observed outcomes, such as death or survival. Through the data of different pathological types of patients screened, spss26 0 statistical software for statistical description, using Kaplan Meier method. Draw the survival curve and estimate the survival rate and mortality of patients. The inter group comparison of survival time distribution adopts log rank test to conduct multi factor Cox analysis on the variables with statistical significance of P α = 0.05, P < 0.05. Result: (1) Kaplan Meier univariate analysis: different pathological stages of T stage, N stage and M stage have an impact on the survival of patients, which is statistically significant (P < 0.05), and can affect the survival of patients to varying degrees. (2) Cox multivariate analysis: T stage, N stage and M stage were independent prognostic factors affecting the survival time of patients. Conclusion: Different T, N and M pathological stages of different cervical cancer patients can affect the prognosis of cervical cancer patients to varying degrees. They have a significant impact on the mortality and survival rate of cervical cancer patients, and can provide relevant basis for the development and improvement of the treatment scheme of cervical cancer. 展开更多
关键词 SEER数据库 宫颈癌 T n m病理分期 预后 影响因素分析
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纳米贝氏体对GCr15轴承钢M/B_(n)复合组织和力学性能的影响
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作者 周丽娜 杨晓峰 +2 位作者 麻健鹏 魏英华 于兴福 《金属热处理》 北大核心 2025年第5期40-45,共6页
通过对GCr15轴承钢采用油淬和200℃等温盐淬热处理,获得马氏体(M)和不同纳米贝氏体(B_(n))含量的复合组织(M/B_(n))。采用扫描电镜、洛氏硬度计和冲击试验机对微观组织、硬度和冲击性能进行表征,以研究M/B_(n)复合组织中纳米贝氏体含量... 通过对GCr15轴承钢采用油淬和200℃等温盐淬热处理,获得马氏体(M)和不同纳米贝氏体(B_(n))含量的复合组织(M/B_(n))。采用扫描电镜、洛氏硬度计和冲击试验机对微观组织、硬度和冲击性能进行表征,以研究M/B_(n)复合组织中纳米贝氏体含量对GCr15轴承钢组织和性能的影响。结果表明,油淬GCr15轴承钢的组织主要由球状颗粒碳化物、回火马氏体和残留奥氏体组成;等温淬火后,轴承钢的组织主要由球状碳化物、回火马氏体、贝氏体、残留奥氏体和二次析出细小碳化物组成。随着纳米贝氏体含量的增加,GCr15钢的硬度逐渐降低。采用860℃奥氏体化,盐浴200℃保温2 h,再经200℃回火后,获得的M/B_(n)复合组织硬度与845℃奥氏体化,油淬后经155℃回火获得的马氏体组织的硬度相当。此时,具有M/B_(n)复合组织钢中纳米贝氏体含量为47%,硬度为61.5 HRC,全马氏体组织钢的硬度为61.1 HRC,M/B_(n)复合组织钢的冲击吸收能量为9.92 J,全马氏体组织钢的冲击吸收能量为7.67 J,具有M/B_(n)复合组织钢的冲击吸收能量提高了29.34%,表明在硬度相当的情况下,M/B_(n)复合组织具有更好的综合力学性能。 展开更多
关键词 GCR15轴承钢 纳米贝氏体 m/B_(n)复合组织 硬度 冲击性能
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Comparative study on forming limit prediction of AA7075-T6 sheet with M−K model and Lou−Huh criterion 被引量:12
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作者 Guo-jiang DONG Zhi-wei CHEN +1 位作者 Zhuo-yun YANG Bo-cheng FAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第6期1463-1477,共15页
In order to effectively predict the fracture of AA7075-T6 sheet, the forming limit curves of AA7075-T6 high-strength sheet were drawn according to Morciniak Kuczyski (M K) model and Lou Huh criterion, respectively. Th... In order to effectively predict the fracture of AA7075-T6 sheet, the forming limit curves of AA7075-T6 high-strength sheet were drawn according to Morciniak Kuczyski (M K) model and Lou Huh criterion, respectively. The errors between the predicted values of the two theoretical prediction models and experimental values were calculated by error analysis. The forming limit curves were verified by the punch stretch test to evaluate the prediction accuracy of M K model and Lou Huh criterion. The error analysis results show that the mean error of Lou Huh criterion with the optimal parameters for all tensile specimens is 25.04%, while the mean error of M K model for all tensile specimens is 74.24%. The prediction accuracy of Lou Huh criterion in predicting the fracture of AA7075-T6 sheet is higher. The punch stretch test results show that the forming limit curve drawn by Lou Huh criterion can effectively predict the fracture of AA7075-T6 sheet, but the prediction accuracy of M K model is relatively poor. 展开更多
关键词 ductile fracture criterion m K model forming limit diagram AA7075-T6 sheet
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gl(2,1)到模李超代数W(m,n,q)的权导子
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作者 关露萍 孙丽萍 刘文德 《东北师大学报(自然科学版)》 北大核心 2025年第2期12-16,共5页
在特征p>2的域上,基于一般线性李超代数gl(2,1)到Cartan型模李超代数W(m,n,q)零部的嵌入关系,W(m,n,q)在伴随表示的意义下可视为gl(2,1)模.通过对W(m,n,q)进行子模分解和权空间分解,计算出了gl(2,1)到W(m,n,q)的保权导子,并得到了一... 在特征p>2的域上,基于一般线性李超代数gl(2,1)到Cartan型模李超代数W(m,n,q)零部的嵌入关系,W(m,n,q)在伴随表示的意义下可视为gl(2,1)模.通过对W(m,n,q)进行子模分解和权空间分解,计算出了gl(2,1)到W(m,n,q)的保权导子,并得到了一阶上同调群. 展开更多
关键词 李超代数W(m n q) 导子 权导子
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在(p,N)-策略控制下耐烦服务员不中断多重休假M/G/1排队的最优控制策略
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作者 尹伶玉 唐应辉 旷欣宇 《控制与决策》 北大核心 2025年第7期2185-2193,共9页
研究在(p,N)-策略控制下耐烦服务员不中断多重休假M/G/1排队系统,其中每当系统变空时,服务员去进行一次不中断的休假,当服务员休假回来时,若系统中等待服务的顾客数大于等于事先设置的正整数阈值N(N≥1),则服务员立即开始服务直到系统... 研究在(p,N)-策略控制下耐烦服务员不中断多重休假M/G/1排队系统,其中每当系统变空时,服务员去进行一次不中断的休假,当服务员休假回来时,若系统中等待服务的顾客数大于等于事先设置的正整数阈值N(N≥1),则服务员立即开始服务直到系统再次空竭;若系统中有顾客但顾客数少于N个,则服务员以概率p(0≤p≤1)开始服务,以概率1-p不服务,处于通常的闲期,直到系统中的顾客数累积到N时才服务.通过系统稳态队长的随机分解定理得到系统稳态队长分布的概率母函数和平均队长表达式,同时应用Little公式得到任意顾客的平均等待时间表达式.然后建立系统的费用结构模型,利用更新报酬定理推得系统长期运行单位时间的期望成本费用函数.进一步,在没有平均等待时间和有平均等待时间约束下,通过数值实例分别讨论系统的优化控制问题,并确定使系统费用最小的一维最优控制策略N^(*)和当休假时间为T时的二维最优控制策略(N^(*),T^(*)). 展开更多
关键词 m/G/1排队 (p n)-策略 不中断多重休假 队长的随机分解 最优控制策略
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lncRNA JPX通过m^(6)A-YTHDC2轴上调细胞质p21蛋白促进RA-FLS增殖
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作者 韦丽丽 杨洁 +1 位作者 沈维干 周玮 《扬州大学学报(农业与生命科学版)》 北大核心 2025年第5期56-65,共10页
为揭示lncRNA JPX对类风湿关节炎成纤维细胞样滑膜细胞(rheumatoid arthritis fibroblast-like synoviocytes,RA-FLS)活性影响的分子机制,通过RT-qPCR、Western blot、甲基化RNA免疫沉淀(methylated RNA immunoprecipitation,MeRIP)、... 为揭示lncRNA JPX对类风湿关节炎成纤维细胞样滑膜细胞(rheumatoid arthritis fibroblast-like synoviocytes,RA-FLS)活性影响的分子机制,通过RT-qPCR、Western blot、甲基化RNA免疫沉淀(methylated RNA immunoprecipitation,MeRIP)、荧光素酶报告基因、RNA免疫沉淀(RNA immunoprecipitation,RIP)、蛋白质稳定性以及体外功能试验等检测JPX调控RA-FLS活性的作用及其分子机制。结果表明:JPX可上调p21 mRNA的N^(6)甲基腺苷(N6-methyladenosine,m^(6)A)修饰水平,YTHDC2可通过与JPX介导的m^(6)A修饰的p21 mRNA结合,上调RA-FLS中p21蛋白水平;同时,JPX可增加p21蛋白在细胞质中的富集而促进RA-FLS的增殖。综上,JPX可通过m^(6)A-YTHDC2-p21轴以及调控p21蛋白在细胞中的分布调节RA-FLS增殖,JPX有可能是一个新的RA诊断和治疗靶点。 展开更多
关键词 lncRnA JPX 类风湿关节炎成纤维细胞样滑膜细胞(RA-FLS) P21 n^(6)甲基腺苷(m^(6)A) 含YTH结构域蛋白2(YTHDC2)
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卟啉直接退火制备M-N-C催化剂与电催化氮气还原
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作者 李启龙 朱卫华 梁旭 《合成化学》 2025年第9期607-615,共9页
氨气是一种理想的能量载体,但传统伯恩-哈珀合成方法条件苛刻,催化剂价格昂贵。电催化氮气还原是一种重要的氮化学转化方法,有望解决氨合成过程中的能源浪费和环境问题。M-N-C型催化剂以其丰富的活性位点和极高的原子利用率被广泛应用... 氨气是一种理想的能量载体,但传统伯恩-哈珀合成方法条件苛刻,催化剂价格昂贵。电催化氮气还原是一种重要的氮化学转化方法,有望解决氨合成过程中的能源浪费和环境问题。M-N-C型催化剂以其丰富的活性位点和极高的原子利用率被广泛应用于此领域。本文以四苯基卟啉自由碱为关键前驱体,利用中温直接退火,并引入不同金属离子,得到多例全新M-N-C型催化剂,并利用SEM、XRD和XPS等手段对材料结构进行了详细表征。研究表明:在体系中引入Fe离子,退火温度为700℃时,表现出最优异的电化学催化性能,NH3产率为12.7μg/(mg·h),Faraday效率为37.5%,且在长时间电解和多次循环使用中表现出优异的电化学稳定性,优于目前报道的多数M-N-C型催化剂。 展开更多
关键词 卟啉 m-n-C催化剂 氮气还原 电化学催化 电化学稳定性
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SerpinA3N通过抑制Müller细胞炎症减轻糖尿病小鼠视网膜神经损伤的作用机制研究
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作者 孙时磊 吕涛 +1 位作者 左中夫 冯闯 《眼科新进展》 北大核心 2025年第12期949-955,共7页
目的探讨丝氨酸蛋白酶抑制剂A3N(SerpinA3N)通过抑制Müller细胞炎症减轻糖尿病小鼠视网膜神经损伤的作用机制。方法将36只(72眼)db/db小鼠随机分为db/db组、db/db+过表达SerpinA3N腺相关病毒(AAV-SerpinA3N)组及db/db+空载体腺相... 目的探讨丝氨酸蛋白酶抑制剂A3N(SerpinA3N)通过抑制Müller细胞炎症减轻糖尿病小鼠视网膜神经损伤的作用机制。方法将36只(72眼)db/db小鼠随机分为db/db组、db/db+过表达SerpinA3N腺相关病毒(AAV-SerpinA3N)组及db/db+空载体腺相关病毒SerpinA3N(NC-SerpinA3N)组,每组12只。随机选取12只年龄匹配的同窝健康雄性小鼠作为健康对照组(db/m组)。各组小鼠进行相应处理后4周处死。免疫荧光染色检测小鼠视网膜SerpinA3N和胶质纤维酸性蛋白(GFAP)共定位情况,HE染色观察小鼠视网膜组织病理变化,TUNEL染色检测小鼠视网膜神经节细胞(RGCs)凋亡情况,免疫组织化学检测小鼠视网膜GFAP表达,ELISA检测小鼠视网膜组织中炎症因子[白细胞介素(IL)-1β、IL-6、IL-18和肿瘤坏死因子α(TNF-α)]含量。将SerpinA3N预测靶基因导入String数据库构建蛋白质-蛋白质相互作用网络(PPI),依评分结果筛选最高分靶点后进行分子对接。Western blot检测小鼠视网膜组织中SerpinA3N、核因子κB(NF-κB)和脾焦点形成病毒前病毒整合癌基因(Spi1)蛋白表达水平。结果免疫荧光染色结果显示,视网膜组织中SerpinA3N与GFAP共定位表达。与db/m组相比,db/db组、db/db+NC-SerpinA3N组和db/db+AAV-SerpinA3N组小鼠视网膜厚度和RGCs数量均减少,TUNEL阳性细胞数量、GFAP阳性相对表达强度及各种炎症因子含量均增加,SerpinA3N蛋白表达水平均减少,NF-κB和Spi1蛋白表达水平均增加(均为P<0.05)。与db/db组相比,db/db+AAV-SerpinA3N组小鼠视网膜厚度和RGCs数量均增加,TUNEL阳性细胞数量、GFAP阳性相对表达强度及各种炎症因子含量均减少,SerpinA3N蛋白表达水平增加,NF-κB和Spi1蛋白表达水平均减少(均为P<0.05)。与db/db+AAV-SerpinA3N组相比,db/db+NC-SerpinA3N组小鼠视网膜厚度和RGCs数量均减少,TUNEL阳性细胞数量、GFAP阳性相对表达强度及各种炎症因子含量均增加,SerpinA3N蛋白表达水平减少,NF-κB和Spi1蛋白表达水平均增加(均为P<0.05)。PPI结果显示,SerpinA3N与Spi1存在相互作用;分子对接结果显示,Spi1与SerpinA3N周围残基可形成氢键。结论过表达SerpinA3N可抑制Müller细胞炎症改善糖尿病小鼠视网膜神经损伤,其机制可能与抑制Spi1/NF-κB信号通路相关。 展开更多
关键词 糖尿病视网膜病变 mÜLLER细胞 SerpinA3n 炎症反应
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A two-sample KS test with m out of n bootstrap for massive data
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作者 XIE Xiaoyue TIAN Xinyu SHI Jian 《纯粹数学与应用数学》 2025年第4期744-760,共17页
In the era of big data,traditional statistical inference methods are faced with great challenges.Taking the two-sample distribution test scenario of big data as an example,this paper proposes the BB-KS test based on m... In the era of big data,traditional statistical inference methods are faced with great challenges.Taking the two-sample distribution test scenario of big data as an example,this paper proposes the BB-KS test based on m out of n bootstrap for solving a single-machine memory and computing constraints.It is verified to the feasibility and effectiveness of the proposed test method through theoretical analysis and numerical simulation.The results show that the BB-KS test can improve the calculation efficiency of the test to a certain extent in the single machine scenario. 展开更多
关键词 massive data two sample test the BB-KS method m out of n bootstrap
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具有(2m+1)次非线性项和时空变系数的广义(n+1)维薛定谔方程的相似变换和精确解
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作者 王岗伟 谭子轩 《物理学报》 北大核心 2025年第11期134-140,共7页
薛定谔型方程是一类十分重要的微分方程.高维及变系数薛定谔型方程的研究具有一定的价值和意义.本文利用相似变换推导了(n+1)维(2m+1)次变系数非线性薛定谔方程的一类新的孤子解,给出了系数之间满足的关系.并利用定态薛定谔方程的解,得... 薛定谔型方程是一类十分重要的微分方程.高维及变系数薛定谔型方程的研究具有一定的价值和意义.本文利用相似变换推导了(n+1)维(2m+1)次变系数非线性薛定谔方程的一类新的孤子解,给出了系数之间满足的关系.并利用定态薛定谔方程的解,得到了(n+1)维(2m+1)次变系数非线性薛定谔方程的明暗孤子解.最后,对于特殊的情况,给出了明暗孤立子解的图像,并系统分析了孤子解的空间结构和传播特性. 展开更多
关键词 (n+1)维(2m+1)次非线性薛定谔方程 相似变换 精确解
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Adenosine kinase and ADAL coordinate detoxification of modified adenosines to safeguard metabolism
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作者 Akiko Ogawa 《四川生理科学杂志》 2025年第8期1719-1719,共1页
RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RN... RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RNA-derived modified adenosines,N6-methyladenosine(m6A),N6,N6-dimethyladenosine(m6,6A),and N6-isopentenyladenosine(i6A),are sequentially metabolized into inosine monophosphate(IMP)to mitigate their intrinsic cytotoxicity. 展开更多
关键词 adenosine kinase modified adenosines modified adenosinesn methyladenosine m n n dimethyladenosine m catabolic breakdown modified nucleosides DETOXIFICATIOn inosine monophosphate imp adal
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在服务启动N-策略控制下具有检修策略和不同到达率的M/G/1排队分析
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作者 李丰芮 唐应辉 《运筹学学报(中英文)》 北大核心 2025年第2期113-127,共15页
本文以制造系统为背景,提出一个在服务启动N-策略控制下具有检修策略和不同到达率的M/G/1排队模型。首先运用更新过程理论、全概率分解技术和拉普拉斯变换,研究系统在任意时刻t队长的瞬态性质,得到了瞬态队长分布关于时间t的拉普拉斯变... 本文以制造系统为背景,提出一个在服务启动N-策略控制下具有检修策略和不同到达率的M/G/1排队模型。首先运用更新过程理论、全概率分解技术和拉普拉斯变换,研究系统在任意时刻t队长的瞬态性质,得到了瞬态队长分布关于时间t的拉普拉斯变换表达式。然后在瞬态分析的基础上,使用洛必达法则得到队长稳态分布的递推表达式。最后,在建立费用模型下,应用更新报酬定理,得到系统在长期运行下单位时间内的期望费用表达式,并通过数值实例讨论了系统启动服务的最优控制策略和最优检修策略。 展开更多
关键词 m/G/1排队 检修策略 服务启动n-策略 队长分布 最优策略
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Ménétrier disease:A clinical review
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作者 Ana R Barros Sara Monteiro Jorge Silva 《World Journal of Gastroenterology》 2025年第32期1-9,共9页
Ménétrier disease(MD)is a rare gastric disorder characterized by hypertrophy of the gastric mucosa,resulting in giant gastric folds,excessive mucus secretion,and significant protein loss.It is most common in... Ménétrier disease(MD)is a rare gastric disorder characterized by hypertrophy of the gastric mucosa,resulting in giant gastric folds,excessive mucus secretion,and significant protein loss.It is most common in middle-aged males,although cases have also been reported in children.This condition,also known as hyperplastic hypersecretory gastropathy,primarily affects the fundus and body of the stomach,leading to protein-losing gastropathy due to increased mucosal permeability.The exact pathogenesis of MD remains unclear;however,it has been linked to excessive transforming growth factor-alpha signaling via the epidermal growth factor receptor(EGFR),which promotes mucosal hyperplasia.Clinical manifestations include epigastric pain,nausea,vomiting,anorexia,weight loss,and peripheral edema due to protein-losing enteropathy.Diagnosis is based on clinical presentation,endoscopic findings,and histopathology revealing foveolar hyperplasia and glandular atrophy.Treatment options vary from symptomatic management with proton pump inhibitors and nutritional support to monoclonal antibodies targeting EGFR(e.g.,cetuximab)in severe cases.In refractory situations,gastrectomy may be required.This review highlights the current understanding,diagnostic approaches,and therapeutic strategies for MD. 展开更多
关键词 ménétrier disease Giant hypertrophic gastritis Hypoproteinemic hypertrophic gastropathy HYPOALBUmInEmIA Protein-losing enteropathy
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PB2627V and HA 217 sites synergistically affect the lethality of H9N2 in mice
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作者 Lingcai Zhao Miao Tian +3 位作者 Xifeng Hu Menglu Fan Chenglin Hou Jihui Ping 《Virologica Sinica》 2025年第1期35-49,共15页
The H9N2 subtype avian influenza virus(AIV)continues to propagate and undergo evolution within China,thereby posing a significant threat to the poultry industry.This study encompassed the collection of 436 samples and... The H9N2 subtype avian influenza virus(AIV)continues to propagate and undergo evolution within China,thereby posing a significant threat to the poultry industry.This study encompassed the collection of 436 samples and swabs in East China over the period spanning 2018 to 2019,from which 31 strains of the H9N2 subtype viruses were isolated and purified.We revealed that the HA and NA genes of the 31 isolates categorized within the Y280 branch,while the PB2 and M genes were associated with the G1 branch,and the remaining genes aligned with the F/98 branch.Despite this alignment,antigenic mapping demonstrated differences between the 2018 and 2019 strains,with the early vaccine strains displaying low serological reactivity toward these isolates.Notably,the CK/SH/49/19 isolate exhibited lethality in mice,characterized by a PB2 E627V mutation and a HA deletion at amino acid position 217.Mechanistically,in vitro studies showed that the influenza virus CK/SH/49/19 carrying PB2627V and HA 217M mutations displayed enhanced replication capacity,attributed to the heightened activity of the polymerase with PB2627V.Moreover,the absence of the amino acid at the HA 217 site obstructed viral adsorption and internalization,resulted in lower activation pH,and impeded the virus budding process.Critically,in vivo experiments revealed that CK/SH/49/19(PB2627V,HA 217Δ)triggered a robust activation of interferon response and interferon-stimulated genes.This study furnished a theoretical foundation for the scientific prevention and control strategies against H9N2 subtype avian influenza. 展开更多
关键词 Avian influenza virus(AIV) H9n2 PB2627V HA 217m PATHOGEnICITY
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光影木构的村镇叙事 法国M.I.N.E数字与生态创新之家
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作者 小麦(编译) 《室内设计与装修》 2025年第9期74-79,共6页
M.I.N.E数字与生态创新之家位于法国韦纳雷莱洛梅的莱洛姆阿莱西亚火车站对面,原邮局地块的三角形几何结构,奠定了项目的整体造型基础和设计理念。建筑与周边环境保持了适当的距离,形成一个五棱柱的体量。整个建筑没有主次朝向之分,向... M.I.N.E数字与生态创新之家位于法国韦纳雷莱洛梅的莱洛姆阿莱西亚火车站对面,原邮局地块的三角形几何结构,奠定了项目的整体造型基础和设计理念。建筑与周边环境保持了适当的距离,形成一个五棱柱的体量。整个建筑没有主次朝向之分,向城市的各个方向展现自己。倾斜的屋顶使建筑独具特色,不同的观察角度呈现不同的面貌,既统一又多样,既熟悉又神秘。 展开更多
关键词 数字与生态创新 m.I.n.E 村镇叙事
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OTUD7B Stabilization by METTL14-Mediated m6A Methylation Drives HIF-1α Expression in Esophageal Squamous Cell Carcinoma
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作者 Fei Ren Yansen Cai Yang Song 《Oncology Research》 2025年第8期2055-2074,共20页
Objectives:Epigenetic changes,particularly N6-methyladenosine(m6A)modifications,play a pivotal role in cancer development.This study explored the role of ovarian tumor deubiquitinase 7B(OTUD7B)in esophageal squamous c... Objectives:Epigenetic changes,particularly N6-methyladenosine(m6A)modifications,play a pivotal role in cancer development.This study explored the role of ovarian tumor deubiquitinase 7B(OTUD7B)in esophageal squamous cell carcinoma(ESCC)in the context of m6A methylation and the hypoxia-inducible factor-1α(HIF-1α)pathway.Methods:The GSE179267 dataset was used to conduct differential gene expression analysis to identify key m6A-enriched genes.The Cancer Genome Atlas(TCGA),Cancer Cell Line Encyclopedia(CCLE),and Sequence-based RNA Adenosine Methylation Site Predictor(SRAMP)databases were used to evaluate the expression of OTUD7B in ESCC and its correlation with methyltransferase-like 14(METTL14)and HIF-1α.The m6A content in total RNA extracted from ESCC cells was assessed using a dot blot assay.Gene-specific m6A-PCR was used to quantify m6A modifications in OTUD7B mRNA.The functional role of OTUD7B was explored using clonogenic and Transwell assays.The effect of OTUD7B on HIF-1αubiquitination was detected using a co-immunoprecipitation assay.Results:OTUD7B was identified as a pivotal m6A-driven oncogene correlated with METTL14 and HIF-1α.METTL14 enhanced the mRNA stability and expression of OTUD7B through m6A methylation.OTUD7B overexpression counteracted the inhibitory effects of METTL14 knockdown on cell proliferation and invasion and stabilized HIF-1αby promoting deubiquitination.Conclusion:METTL14 plays a crucial role in the stabilization of OTUD7B through m6A methylation,thereby inhibiting the ubiquitin-proteasomal degradation of HIF-1αin ESCC.These findings highlight the potential of targeting the METTL14-OTUD7B axis as a therapeutic strategy for ESCC. 展开更多
关键词 Esophageal squamous cell carcinoma(ESCC) n6-methyladenosine(m6A) ovarian tumor deubiquiti-
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N6-Methyladenosine Promotes the Transcription of c-Src Kinase via IRF1 to Facilitate the Proliferation of Liver Cancer
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作者 Yanxi Peng Honggen Yuan +5 位作者 Zhanjie Jiang Xiaoqing Ou Qian Zhang Kexin Yi Yanbin Meng Qun Xie 《Oncology Research》 2025年第7期1679-1693,共15页
Background:Expression of mRNA is widely regulated by N6-methyladenosine(m6A).An increasing number of studies have shown that m6A methylation,facilitated by methyltransferase 3(METTL3),is crucial in the progression of ... Background:Expression of mRNA is widely regulated by N6-methyladenosine(m6A).An increasing number of studies have shown that m6A methylation,facilitated by methyltransferase 3(METTL3),is crucial in the progression of tumors.Previous reports have indicated the involvement of both METTL3 and c-Src kinase in the evolution of liver cancer.However,the potential connection between c-Src and the METTL3-mediated mechanism in liver cancer progression remains elusive.Methods:The correlation expression between c-Src and METTL3 between liver cancer patients and the control group was analyzed using the TCGA database,and was further demonstrated by Western blot and RT-qPCR.The functional roles of c-Src in METTL3-regulated liver cancer progression were investigated by cell proliferation assays and colony formation assays.The regulatory mechanism of METTL3 in c-Src expression was accessed by RNA-immunoprecipitation(RIP)-qPCR.Results:We demonstrated that c-Src kinase promoted liver cancer development,and the expression of SRC(encodes c-Src kinase)was positively correlated with METTL3 in liver cancer cases.We showed that SRC mRNA could be m6A-modified,and METTL3 regulated the transcription of SRC mRNA through interferon regulatory factor 1(IRF1).We revealed that IRF1,the expression of which was positively regulated byMETTL3,was a novel transcription factor of c-Src.Lastly,The pro-proliferative effect of METTL3 on hepatocellular carcinoma was mechanistically linked to IRF1/c-Src axis activation,as evidenced by our experimental data.Conclusion:Results suggested that the METTL3/IRF1/c-Src axis played potential oncogenic roles in liver cancer development and the axis may be a promising therapeutic target in the disease. 展开更多
关键词 n6-methyladenosine(m6A) C-SRC interferon regulatory factor 1(IRF1) liver cancer hepatocellular carcinoma(HCC)
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