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SET信号参与的自噬在胃癌进展中的分子机制研究
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作者 张伟 蔡振花 +2 位作者 杨晨 李浩闯 王玉宏 《现代消化及介入诊疗》 2025年第3期305-308,共4页
目的 探究人类SET核原癌基因(SET nuclear proto-oncogene,SET)对胃癌(gastric cancer,GC)细胞自噬途径的作用及机制。方法 通过生物信息学的方法分析SET在GC患者和健康人群中的表达差异。通过慢病毒转染GC细胞系SGC-7901,得到稳定敲低... 目的 探究人类SET核原癌基因(SET nuclear proto-oncogene,SET)对胃癌(gastric cancer,GC)细胞自噬途径的作用及机制。方法 通过生物信息学的方法分析SET在GC患者和健康人群中的表达差异。通过慢病毒转染GC细胞系SGC-7901,得到稳定敲低SET的细胞株。CCK-8法检测细胞增殖活性,划痕实验检测细胞迁移能力,Transwell试验检测细胞侵袭活性。构建裸鼠负瘤模型,3周后取下肿瘤组织。Western blot检测肿瘤组织内自噬相关蛋白sequestosome 1蛋白(sequestosome 1,p62)和自噬相关基因5(autophagy related 5,ATG5)蛋白表达水平。结果 生物信息学分析表明,SET在GC患者中表达水平显著高于健康人群。SET敲低后,SGC7901细胞增殖活性显著降低,迁移和侵袭能力均受到显著抑制。SET敲低抑制了GC肿瘤体内生长。与对照组肿瘤组织相比,SET敲低组肿瘤组织内自噬相关蛋白p62和ATG5表达水平显著升高。结论 SET的表达能够通过抑制细胞自噬途径促进GC进展。 展开更多
关键词 set 自噬 胃癌
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非小细胞肺癌组织中SETDB1、KDM1A、CMTM6表达水平及临床意义
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作者 卢晨 宁光耀 +4 位作者 司盼盼 刘文健 张春盛 张仁泉 赵元 《医学研究与战创伤救治》 北大核心 2025年第9期939-944,共6页
目的探讨非小细胞肺癌(NSCLC)组织中SET结构域分支型组蛋白赖氨酸甲基转移酶1(SETDB1)、赖氨酸特异性组蛋白去甲基化酶1(KDM1A)、趋化因子样因子样MARVEL跨膜结构域含蛋白6(CMTM6)表达与临床病理特征及与预后的关系。方法选择2021年8月... 目的探讨非小细胞肺癌(NSCLC)组织中SET结构域分支型组蛋白赖氨酸甲基转移酶1(SETDB1)、赖氨酸特异性组蛋白去甲基化酶1(KDM1A)、趋化因子样因子样MARVEL跨膜结构域含蛋白6(CMTM6)表达与临床病理特征及与预后的关系。方法选择2021年8月至2022年8月安徽医科大学第一附属医院胸外科收治的102例NSCLC患者。收集癌组织及癌旁组织标本,采用免疫组化法检测癌组织及癌旁组织SETDB1、KDM1A、CMTM6的表达;根据预后情况将患者分为生存组(n=78)和死亡组(n=24),多因素Cox回归分析影响NSCLC患者发生死亡的影响因素,ROC分析SETDB1、KDM1A、CMTM6对NSCLC的诊断价值,Kaplan-Meier法分析SETDB1、KDM1A、CMTM6表达与患者预后的关系。结果NSCLC癌组织SETDB1、KDM1A、CMTM6阳性表达率较癌旁组织均升高(P<0.05);与组织中高分化、TNM分期Ⅰ-Ⅱ期、无淋巴结转移的患者比较,组织低分化、TNM分期Ⅲ-Ⅳ期、有淋巴结转移的患者癌组织中SETDB1、KDM1A、CMTM6阳性表达率均升高(P<0.05);SETDB1、KDM1A、CMTM6三者联合对NSCLC有较高的诊断价值。SETDB1、KDM1A、CMTM6是NSCLC患者发生死亡的危险因素(P<0.05)。SETDB1阳性表达患者生存率低于SETDB1阴性表达患者(P=0.025),KDM1A阳性表达患者生存率低于KDM1A阴性表达患者(P=0.044),CMTM6阳性表达患者生存率低于CMTM6阴性表达患者(P=0.008)。结论NSCLC患者癌组织中SETDB1、KDM1A、CMTM6阳性表达率升高,三者的表达水平与组织分化程度、TNM分期、淋巴结转移以及生存率有关。 展开更多
关键词 非小细胞肺癌 set结构域分支型组蛋白赖氨酸甲基转移酶1 临床病理特征 赖氨酸特异性组蛋白去甲基化酶1 趋化因子样因子样MARVEL跨膜结构域含蛋白6 预后
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穴位针刺结合SET悬吊技术对肩袖损伤患者术后疼痛、肌肉萎缩的影响
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作者 刘小平 陈飞宇 包烨华 《新中医》 2025年第10期87-92,共6页
目的:分析穴位针刺结合SET悬吊技术对肩袖损伤患者术后疼痛、肌肉萎缩的影响。方法:选取2023年1—12月浙江中医药大学附属杭州市中医院收治的肩袖损伤患者70例,按就诊号的尾数奇偶性随机分为对照组与研究组各35例。对照组采用穴位针刺治... 目的:分析穴位针刺结合SET悬吊技术对肩袖损伤患者术后疼痛、肌肉萎缩的影响。方法:选取2023年1—12月浙江中医药大学附属杭州市中医院收治的肩袖损伤患者70例,按就诊号的尾数奇偶性随机分为对照组与研究组各35例。对照组采用穴位针刺治疗,研究组在对照组的基础上联合SET悬吊技术进行干预。比较2组肩关节功能[加州大学(UCLA)肩关节评分系统评分]、疼痛程度[视觉模拟评分法(VAS)评分]、肩袖肌积分肌电值(iEMG)、肌肉萎缩程度及肩袖肌肉肌腱弹性E值。结果:治疗后,2组UCLA肩关节功能评分均较治疗前升高(P<0.05),且研究组UCLA肩关节功能评分高于对照组(P<0.05)。治疗后,2组肩关节外旋、内旋、内收、外展活动度均较治疗前增大(P<0.05),且研究组肩关节各项活动度均大于对照组(P<0.05)。治疗后,2组疼痛VAS评分均较治疗前降低(P<0.05),且研究组VAS评分低于对照组(P<0.05)。治疗后,2组外展角速度60、120 rad/s时三角肌前束、中束、后束iEMG均较治疗前增大(P<0.05),且研究组上述各项iEMG均大于对照组(P<0.05)。治疗后,研究组肌肉萎缩程度分级改善优于对照组,差异有统计学意义(P<0.05)。治疗后,2组肩袖肌肉肌腱弹性E值均较治疗前降低(P<0.05),且研究组E值低于对照组(P<0.05)。结论:穴位针刺结合SET悬吊技术对肩袖损伤患者术后恢复具有积极影响,可有效减轻术后疼痛,抑制肌肉萎缩,并改善肌肉功能和肌腱弹性。 展开更多
关键词 肩袖损伤 穴位针刺 set悬吊技术 肌肉萎缩 加州大学肩关节评分系统 肩袖肌积分肌电值
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广义Z-numbers证据下考虑专家影响力和评价值一致性的应急决策方法
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作者 张磊 韩可可 叶鑫 《中国管理科学》 北大核心 2025年第6期160-170,共11页
复杂不确定情景下突发事件应急决策呈现多属性群决策的特征,且在决策信息不确定的情形下,信息的可靠度会影响决策结果。本文提出一种广义Z-numbers证据下考虑专家影响力和评价值一致性的应急决策方法。首先,基于广义Z-numbers对应急决... 复杂不确定情景下突发事件应急决策呈现多属性群决策的特征,且在决策信息不确定的情形下,信息的可靠度会影响决策结果。本文提出一种广义Z-numbers证据下考虑专家影响力和评价值一致性的应急决策方法。首先,基于广义Z-numbers对应急决策问题建模,并构建信任网络分析专家影响力,提出融合专家影响力和评价可靠度的评价值权重分析方法;其次,根据犹豫模糊评价值的交集分析专家的评价值一致性情形,提出不同一致性情形下的证据生成方法,进而利用D-S证据理论融合多证据信息进行备选应对方案的优选决策;最后,以传染性疾病医疗废物处置装置的决策为例,分析验证了所提方法的有效性和决策结果的可信性。 展开更多
关键词 应急决策 广义Z-numbers D-S证据理论 专家影响力 一致性
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基于Level Set方法的HG-80钢晶粒长大模型的建模与仿真
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作者 刘铭阳 陈学文 +5 位作者 周正 毛怡然 徐栋栋 李强 易浩 周旭东 《材料热处理学报》 北大核心 2025年第6期162-170,共9页
为了准确预测HG-80钢的晶粒长大过程并调控其微观组织,在900~1200℃的保温温度和10~1200s的保温时间条件下,采用Gleeble-1500D型热模拟机对其进行等温保温实验,分析其晶粒长大过程,并基于实验数据建立了Burke-Turnbull晶粒长大动力学模... 为了准确预测HG-80钢的晶粒长大过程并调控其微观组织,在900~1200℃的保温温度和10~1200s的保温时间条件下,采用Gleeble-1500D型热模拟机对其进行等温保温实验,分析其晶粒长大过程,并基于实验数据建立了Burke-Turnbull晶粒长大动力学模型。通过二次开发将计算所得的Burke-Turnbull模型参数导入DIGIMU■软件中,从晶粒尺寸分布、晶粒生长动力学和晶粒拓扑结构等方面,基于Level Set方法建立了描述HG-80钢的晶粒长大模型并通过DIGIMU■软件进行仿真计算。结果表明:随着保温时间的增加,实验钢的晶粒尺寸明显增大,晶粒生长速率逐渐减小,呈抛物线状增长;为了验证Burke-Turnbull模型的准确性,将平均晶粒尺寸的模型预测值与实验值进行对比,相关系数R为0.991,表明该模型的准确性较高;通过Level Set方法仿真计算得出的晶粒形貌与实验结果吻合良好,证明该模型能有效预测不同热处理条件下HG-80钢的晶粒长大过程。 展开更多
关键词 HG-80钢 Level set方法 晶粒长大 Burke-Turnbull模型
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Preliminary Identification of a Prime Number Other Than 2 and 3, the Origin of Twin Prime Numbers, the Structure of the Chain of Prime Numbers and the Set of Prime Numbers Less Than a Given Integer
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作者 Mady Ndiaye 《Advances in Pure Mathematics》 2024年第1期30-48,共19页
The application of the Euclidean division theorem for the positive integers allowed us to establish a set which contains all the prime numbers and this set we called it set of supposedly prime numbers and we noted it ... The application of the Euclidean division theorem for the positive integers allowed us to establish a set which contains all the prime numbers and this set we called it set of supposedly prime numbers and we noted it E<sub>sp</sub>. We subsequently established from the previous set the set of non-prime numbers (the set of numbers belonging to this set and which are not prime) denoted E<sub>np</sub>. We then extracted from the set of supposedly prime numbers the numbers which are not prime and the set of remaining number constitutes the set of prime numbers denoted E<sub>p</sub>. We have deduced from the previous set, the set of prime numbers between two natural numbers. We have explained during our demonstrations the origin of the twin prime numbers and the structure of the chain of prime numbers. 展开更多
关键词 Supposedly Prime numbers Non-Prime numbers Prime numbers Prime numbers Less Than a Given Integer Prime numbers between Two Given Integers
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Proof of Concept for a Twin Prime Number Universe Using Set Theory
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作者 John R. Crary 《American Journal of Computational Mathematics》 2024年第3期305-317,共13页
The Fine Structure Constant (eFSC) Model attempts to give a classical definition to a magical number that underlies much of quantum physics. The Fine Structure Constant (α) value equal to 137.03599206 represents a di... The Fine Structure Constant (eFSC) Model attempts to give a classical definition to a magical number that underlies much of quantum physics. The Fine Structure Constant (α) value equal to 137.03599206 represents a dimensionless constant that characterizes the strength of the electromagnetic (EM) interaction between subatomic charged particles. Python-generated property counts for the twin prime force F{139/137} show that the adjusted ratio gives a value of α = 137.036. This implies a mathematical framework underlying this constant is based on twin prime numbers and set theory. This study attempts to demonstrate a proof of concept that a hierarchy of fractional twin prime (αII) forces replicates the quantum nature of the universe and is aligned with the Standard Model of Particle Physics. An expanded eFSC Model demonstrates that twin prime forces and their property sets are mathematically viable substitutes for nuclear reactions, as demonstrated for the Beta-minus decay of neutrons into protons. Most significantly, the positive and negative prime numbers define these nuclear reactants and products as positive or negatively charged ions. Furthermore, the eFSC Model provides new insights regarding the hierarchy of EM forces underlying the quantum nature of the universe. 展开更多
关键词 Fine Structure Constant (α) Prime numbers set Theory Conceptual Model Quantum Physics Light and Matter Beta-Minus Decay
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基于SET-FAHP-TRIZ的老年人公共座椅设计研究
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作者 梁熙楠 刘宗明 《湖南包装》 2025年第1期150-154,共5页
针对老年人公共座椅存在功能与形式设计上的不足,将SET-FAHP-TRIZ理论应用到设计研究中。利用SET模式进行调研分析,获取产品机会缺口,构建模糊层次分析法(FAHP)的用户需求指标;运用FAHP获取用户需求权重大小,对获取的核心用户需求进行... 针对老年人公共座椅存在功能与形式设计上的不足,将SET-FAHP-TRIZ理论应用到设计研究中。利用SET模式进行调研分析,获取产品机会缺口,构建模糊层次分析法(FAHP)的用户需求指标;运用FAHP获取用户需求权重大小,对获取的核心用户需求进行分析并转化为相对应的设计要素;利用TRIZ理论中的分离原理和矛盾矩阵来解决设计要素中所识别的矛盾冲突,导出理想的老年人公共座椅创新设计方案。通过集成理论减少了设计过程中的主观性和不确定性,解决了老年人公共座椅设计中交互性差、舒适性欠佳的问题。 展开更多
关键词 老年人 公共座椅 set FAHP TRIZ
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基于SET-KJ-FAHP的筇竹家具创新设计研究
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作者 付佳璐 黄圣游 黄奉君 《设计》 2025年第5期5-9,共5页
对筇竹家具进行创新性设计,以解决木材紧缺问题,带动筇竹产地产业发展。采取实地调研的方式,对云南省大关县的筇竹产业有了基本的认识,然后运用SET模型来探讨筇竹家具设计的必要性。接着,通过KJ模型来确定消费者的需求。最终,运用FAHP... 对筇竹家具进行创新性设计,以解决木材紧缺问题,带动筇竹产地产业发展。采取实地调研的方式,对云南省大关县的筇竹产业有了基本的认识,然后运用SET模型来探讨筇竹家具设计的必要性。接着,通过KJ模型来确定消费者的需求。最终,运用FAHP模型来对消费者的需求进行定量化和权重分析。通过模糊综合评价得出筇竹家具设计实践需要改进的方向。对筇竹家具进行需求分析有助于设计师对筇竹家具的创新设计进行进一步思考,研究结果可为筇竹家具的现代化设计提供参考价值。 展开更多
关键词 筇竹家具 产品设计 set KJ FAHP
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重离子导致的SOI SiGe HBT的SET效应数值模拟研究
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作者 李府唐 郭刚 +4 位作者 张峥 孙浩瀚 刘翠翠 史慧琳 欧阳晓平 《半导体技术》 北大核心 2025年第7期714-722,共9页
锗硅异质结双极晶体管(SiGe HBT)具有优异的低温性能以及抗总剂量效应和位移损伤的能力,但是其对单粒子效应(SEE)较敏感。利用计算机辅助设计技术(TCAD)构建了SiGe HBT模型,研究了衬底类型、重离子入射位置、器件温度和重离子线性能量转... 锗硅异质结双极晶体管(SiGe HBT)具有优异的低温性能以及抗总剂量效应和位移损伤的能力,但是其对单粒子效应(SEE)较敏感。利用计算机辅助设计技术(TCAD)构建了SiGe HBT模型,研究了衬底类型、重离子入射位置、器件温度和重离子线性能量转移(LET)值对SiGe HBT单粒子瞬态(SET)效应的影响。研究结果表明,集电极/衬底结及其附近是器件的SET效应敏感区域,绝缘体上硅(SOI)工艺的引入有助于提高SiGe HBT的抗SEE能力。此外,载流子迁移率与自由载流子浓度是影响器件SET温度依赖性的最主要因素,随着温度进一步降低至极端低温,杂质不完全电离的影响也愈发凸显。随着LET值升高,SOI SiGe HBT的SET效应显著增强。尤其在低温与高LET耦合作用下,器件的SET电流峰值和电荷收集量远超在其他辐照条件下的。 展开更多
关键词 锗硅异质结双极晶体管(SiGe HBT) 绝缘体上硅(SOI)工艺 单粒子瞬态(set) 单粒子效应(SEE) 计算机辅助设计技术(TCAD)
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A Synergistic Multi-Attribute Decision-Making Method for Educational Institutions Evaluation Using Similarity Measures of Possibility Pythagorean Fuzzy Hypersoft Sets
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作者 Khuram Ali Khan Saba Mubeen Ishfaq +1 位作者 Atiqe Ur Rahman Salwa El-Morsy 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期501-530,共30页
Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pP... Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pPyFHSS)is more flexible in this regard than other theoretical fuzzy set-like models,even though some attempts have been made in the literature to address such uncertainties.This study investigates the elementary notions of pPyFHSS including its set-theoretic operations union,intersection,complement,OR-and AND-operations.Some results related to these operations are also modified for pPyFHSS.Additionally,the similarity measures between pPyFHSSs are formulated with the assistance of numerical examples and results.Lastly,an intelligent decision-assisted mechanism is developed with the proposal of a robust algorithm based on similarity measures for solving multi-attribute decision-making(MADM)problems.A case study that helps the decision-makers assess the best educational institution is discussed to validate the suggested system.The algorithmic results are compared with the most pertinent model to evaluate the adaptability of pPyFHSS,as it generalizes the classical possibility fuzzy set-like theoretical models.Similarly,while considering significant evaluating factors,the flexibility of pPyFHSS is observed through structural comparison. 展开更多
关键词 Hypersoft set Pythagorean fuzzy hypersoft set computational complexity multi-attribute decision-making optimization similarity measures uncertainty
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脂肪组织特异性Setdb1敲除小鼠的鉴定与生殖器官形态和相关功能蛋白分析
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作者 胡世昌 张啸 +5 位作者 杜杰 杨伊璐 李宁 程佳 曾文先 年瑞 《中国科技论文》 2025年第1期65-72,共8页
为了解脂肪组织中SET结构域分叉组蛋白赖氨酸甲基转移酶1(SET domain bifurcated 1,SETDB1)的主要生理生化功能,以野生小鼠(Setdb1F/F小鼠)为对照,检测了脂肪组织特异性敲除Setdb1小鼠(Fabp4-Setdb1^(-/-)小鼠)的甘油三酯(triglyceride,... 为了解脂肪组织中SET结构域分叉组蛋白赖氨酸甲基转移酶1(SET domain bifurcated 1,SETDB1)的主要生理生化功能,以野生小鼠(Setdb1F/F小鼠)为对照,检测了脂肪组织特异性敲除Setdb1小鼠(Fabp4-Setdb1^(-/-)小鼠)的甘油三酯(triglyceride, TG)含量、脂肪组织和生殖器官的形态以及生殖组织VASA(DEAD-box helicase 4, DDX4)蛋白表达。结果表明:Fabp4-Setdb1^(-/-)小鼠脂肪组织SETDB1蛋白表达减少;Fabp4-Setdb1^(-/-)雄鼠的肝脏和血清中TG含量无显著变化,Fabp4-Setdb1^(-/-)雌鼠血清TG含量显著低于Setdb1F/F雌鼠(P<0.05);而Fabp4-Setdb1^(-/-)小鼠体内脂肪沉积增多,且脂肪细胞单位面积显著增加(P<0.001)。另外,Fabp4-Setdbl^(-/-)雄鼠睾丸生精小管的管壁薄,生精细胞间隙大,VASA表达下降;Fabp4-Setdb1^(-/-)雌鼠卵巢内的卵泡数量减少。研究结果提示脂肪组织特异性敲除Setdb1可明显改变小鼠生殖器官结构和功能。 展开更多
关键词 set结构域分叉组蛋白赖氨酸甲基转移酶1 脂肪组织 生殖器官 小鼠
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甲基转移酶SETD7促进卵巢癌细胞增殖和迁移
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作者 张紫薇 侯雅楠 +4 位作者 黄婷 张博文 李明阳 林琼 邵根宝 《江苏大学学报(医学版)》 2025年第4期318-325,共8页
目的:探讨含有SET结构域的赖氨酸甲基转移酶7(SET domain containing lysine methyltransferase 7,SETD7)在卵巢癌中的表达及其对卵巢癌细胞上皮-间质转化(epithelial-mesenchymal transition,EMT)和增殖迁移能力的影响。方法:采用免疫... 目的:探讨含有SET结构域的赖氨酸甲基转移酶7(SET domain containing lysine methyltransferase 7,SETD7)在卵巢癌中的表达及其对卵巢癌细胞上皮-间质转化(epithelial-mesenchymal transition,EMT)和增殖迁移能力的影响。方法:采用免疫组织化学染色法检测人卵巢癌组织微阵列芯片中SETD7的表达水平,并分析SETD7表达与卵巢癌患者临床病理特征及预后的相关性。通过慢病毒转染构建稳定过表达SETD7的卵巢癌SKOV3细胞株和稳定敲低SETD7的卵巢癌A2780细胞株,采用细胞计数、CCK-8、Transwell和划痕实验检测卵巢癌细胞增殖、迁移能力,采用免疫印迹法测定细胞中EMT相关蛋白的表达水平。结果:与正常卵巢组织相比,人卵巢癌组织中SETD7蛋白表达水平显著上调(P<0.01)。SETD7高表达与卵巢癌患者M分期、FIGO分期和无进展生存期显著相关(P<0.05)。敲减SETD7显著抑制卵巢癌A2780细胞增殖和迁移,过表达则SKOV3细胞与之相反;过表达SETD7,卵巢癌SKOV3细胞中N-钙黏蛋白和Snail表达上调,E-钙黏蛋白表达下调,敲减则A2780细胞与之相反。结论:SETD7在人卵巢癌组织和细胞中表达上调,促进卵巢癌细胞迁移、增殖和EMT进程。 展开更多
关键词 卵巢癌 含有set结构域的赖氨酸甲基转移酶7(setD7) 增殖 迁移 上皮-间质转化
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基于SET/AHP/FBS的失能老人移位辅具设计
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作者 郑智雄 唐德红 谢敏 《包装工程》 北大核心 2025年第16期114-123,共10页
目的为解决失能老人居家移位问题,提高其生活质量。方法构建了基于SET-AHP-FBS的设计策略。首先,通过SET分析法对用户需求进行调研分析,找到产品的设计缺口;其次,运用AHP确定需求权重并使用模糊综合评价法验证层次模型的合理性;再次,将... 目的为解决失能老人居家移位问题,提高其生活质量。方法构建了基于SET-AHP-FBS的设计策略。首先,通过SET分析法对用户需求进行调研分析,找到产品的设计缺口;其次,运用AHP确定需求权重并使用模糊综合评价法验证层次模型的合理性;再次,将用户需求分别转化为产品功能;最后,依据FBS模型,实现产品由功能、行为到结构的映射,从而确定产品各结构模块,输出设计方案。结果基于SET-AHP-FBS的设计策略具有可行性,该策略客观上使得用户需求与产品功能之间形成精准有效的映射关系,并且减少了设计过程中因主观因素而造成的影响。结论能够较为全面的解决失能老人在日常生活中遇到的移位、如厕等一系列问题,同时有效地改善了现有产品常未能准确把握用户核心需求的问题,也为同类产品研究提供了新的设计思路。 展开更多
关键词 产品设计 移位辅具设计 set AHP FBS
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A low Mach number asymptotic analysis of dissipation-reducing methods for curing shock instability 被引量:1
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作者 Hongping GUO Xun WANG Zhijun SHEN 《Applied Mathematics and Mechanics(English Edition)》 2025年第4期723-744,共22页
We are intrigued by the issues of shock instability,with a particular emphasis on numerical schemes that address the carbuncle phenomenon by reducing dissipation rather than increasing it.For a specific class of plana... We are intrigued by the issues of shock instability,with a particular emphasis on numerical schemes that address the carbuncle phenomenon by reducing dissipation rather than increasing it.For a specific class of planar flow fields where the transverse direction exhibits vanishing but non-zero velocity components,such as a disturbed onedimensional(1D)steady shock wave,we conduct a formal asymptotic analysis for the Euler system and associated numerical methods.This analysis aims to illustrate the discrepancies among various low-dissipative numerical algorithms.Furthermore,a numerical stability analysis of steady shock is undertaken to identify the key factors underlying shock-stable algorithms.To verify the stability mechanism,a consistent,low-dissipation,and shock-stable HLLC-type Riemann solver is presented. 展开更多
关键词 Riemann solver numerical shock instability low Mach number HLLC
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Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation
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作者 WU Yuxuan XU Wenyuan +1 位作者 YU Tianlai JI Yongcheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期224-231,共8页
This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal dosages.The mechanism by which phosphate ester affects the setti... This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal dosages.The mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics simulations.Fourier transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane materials.The results demonstrate that a 1%concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of polyurethane.When phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component A.This reduction in interaction slows the setting time.Additionally,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate. 展开更多
关键词 POLYURETHANE RETARDER setting time molecular dynamics diffusion coefficient
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Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
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作者 Haoxing Xie Kaifeng Xing +3 位作者 Jun Zhou Yao Zhao Jian Zhang Jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 Adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
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Health Phys.Abstracts,Volume 128,Number 1
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《辐射防护》 北大核心 2025年第2期191-196,共6页
TENORM Regulation in the United States of America post-West Virginia vs.EPA Spenser Lynn,Charles Wilson,Emily Caffrey1(1.University of Alabama at Birmingham,School of Health Professions,Clinical and Diagnostic Science... TENORM Regulation in the United States of America post-West Virginia vs.EPA Spenser Lynn,Charles Wilson,Emily Caffrey1(1.University of Alabama at Birmingham,School of Health Professions,Clinical and Diagnostic Sciences,Health Physics Program,1720 University Blvd,Birmingham,AL 35294)Abstract:The regulation of technologically enhanced naturally occurring radioactive materials(TENORM)in the United States of America consists of fragmentary rules split between the federal and state governments. 展开更多
关键词 ABSTRACTS number naturally
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The(Homotopy)Fixed Point Set of S^(1)-Actions on Rationally Elliptic 4-Manifolds
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作者 Chen Huimin Liu Xiugui 《南开大学学报(自然科学版)》 北大核心 2025年第3期32-37,共6页
Let X be a closed simply connected rationally elliptic 4-manifold.The rational homotopy type of homotopy fixed point sets X^(hS^(1))is determined,and based on some relations between X^(hS^(1))and X^(S^(1)),the rationa... Let X be a closed simply connected rationally elliptic 4-manifold.The rational homotopy type of homotopy fixed point sets X^(hS^(1))is determined,and based on some relations between X^(hS^(1))and X^(S^(1)),the rational homotopy type of the fixed point set X^(S^(1))is determined. 展开更多
关键词 rationally elliptic 4-manifolds rational homotopy type homotopy fixed point set fixed point set
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The Crossing Number of Two Classes of Join Graphs
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作者 LU Shengxiang WANG Shu WANG Jing 《数学进展》 北大核心 2025年第5期983-991,共9页
Determining the crossing number of a given graph is NP-complete. The cycle of length m is denoted by Cm = v1v2…vmv1. G^((1))_(m) (m ≥ 5) is the graph obtained from Cm by adding two edges v1v3 and vlvl+2 (3 ≤ l ≤ m... Determining the crossing number of a given graph is NP-complete. The cycle of length m is denoted by Cm = v1v2…vmv1. G^((1))_(m) (m ≥ 5) is the graph obtained from Cm by adding two edges v1v3 and vlvl+2 (3 ≤ l ≤ m−2), G^((2))m (m ≥ 4) is the graph obtained from Cm by adding two edges v1v3 and v2v4. The famous Zarankiewicz’s conjecture on the crossing number of the complete bipartite graph Km,n states that cr(Km,n)=Z(m,n)=[m/2][m-1/2][n/2[n-1/2].Based on Zarankiewicz’s conjecture, a natural problem is to study the change in the crossingnumber of the graphs obtained from the complete bipartite graph by adding certain edge sets.If Zarankiewicz’s conjecture is true, this paper proves that cr(G^((1))_(m)+Kn)=Z(m,n)+2[n/2] and cr(G^((2))_(m)+Kn)=Z(m,n)+n. 展开更多
关键词 crossing number DRAWING join graph
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