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0~1岁婴儿牛奶蛋白过敏发生危险因素分析及其预测价值
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作者 赵春桥 汤家会 《中国计划生育学杂志》 2026年第1期193-198,共6页
目的:分析0~1岁婴儿牛奶蛋白过敏发生危险因素并评估各危险因素对0~1岁婴儿牛奶蛋白过敏发生的预测价值。方法:选择2022年10月—2024年3月本院收入的0~1岁牛奶蛋白过敏可疑婴儿200例为研究对象,依据其是否发生牛奶蛋白过敏分为过敏组(n=... 目的:分析0~1岁婴儿牛奶蛋白过敏发生危险因素并评估各危险因素对0~1岁婴儿牛奶蛋白过敏发生的预测价值。方法:选择2022年10月—2024年3月本院收入的0~1岁牛奶蛋白过敏可疑婴儿200例为研究对象,依据其是否发生牛奶蛋白过敏分为过敏组(n=45)和未过敏组(n=155)。回顾性收集所有婴儿及其母亲的临床资料,采用单因素及logistic多因素回归分析影响婴儿牛奶蛋白过敏的危险因素。采用受试者特征工作(ROC)曲线分析危险因素对婴儿牛奶蛋白过敏发生的预测价值。结果:过敏组母孕期抗生素使用史、父亲或母亲过敏史、母亲妊娠期合并贫血、非纯母乳喂养比例均高于未过敏组(均P<0.05)。logistic多因素回归分析显示,母孕期抗生素使用史、父亲或母亲过敏史、母亲妊娠期贫血、非纯母乳喂养是0~1岁婴儿发生牛奶蛋白过敏的高危因素(OR=3.967、4.154、4.594、1.791,P<0.05)。ROC曲线显示,母孕期抗生素使用史、父亲或母亲过敏史、母亲妊娠期贫血、非纯母乳喂养联合预测0~1岁婴儿牛奶蛋白过敏的曲线下面积为0.838,灵敏度79.0%,特异度88.7%,优于各因素单独预测(P<0.05)。结论:0~1岁婴儿牛奶蛋白过敏的发生受多种因素的影响,包括母孕期抗生素使用史、父亲或母亲过敏史、母亲妊娠期贫血、非纯母乳喂养,各因素联合评估可为0~1岁婴儿牛奶蛋白过敏的发生提供预警信号,临床应重点筛查上述因素并及早采取防治措施。 展开更多
关键词 0~1岁婴儿 牛奶蛋白过敏 危险因素 预测价值
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Glucocorticoid-insulin like growth factor 1 axis programming might be involved in pancreaticβ-cell dysplasia and dysfunction in female offspring rats exposed to caffeine prenatally
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作者 Shuxia Gui Xiaoling Guo +2 位作者 Yongguo Dai Hao Kou Hui Wang 《Food Science and Human Wellness》 2025年第10期4262-4277,共16页
Prenatal caffeine exposure(PCE)leads to intrauterine growth retardation and altered glucose homeostasis after birth,but the underlying mechanism remains unclear.This study aims to investigate the alteration of pancrea... Prenatal caffeine exposure(PCE)leads to intrauterine growth retardation and altered glucose homeostasis after birth,but the underlying mechanism remains unclear.This study aims to investigate the alteration of pancreatic development and insulin biosynthesis in the PCE female offspring and explore the intrauterine programming mechanism.Pregnant rats were orally treated with 120 mg/(kg·day)of caffeine from gestational day(GD)9 to 20.Results showed that fetal pancreaticβ-cells in the PCE group exhibited reduced mass and impaired insulin synthesis function,as evidenced by decreased expression of developmental and functional genes and reduced pancreatic insulin content.At postnatal week(PW)12,the PCE offspring exhibited glucose intolerance,diminishedβ-cell mass,and lower blood insulin levels.However,by PW28,glucose tolerance showed some improvement.Both in vivo and in vitro findings collectively indicated that excessive serum corticosterone(CORT)levels of the PCE fetuses may act through the activation of the pancreatic glucocorticoid receptor(GR)and recruitment of histone deacetylase 9(HDAC9),leading to H3K9 deacetylation in promoter and downregulation of insulin-like growth factor 1(IGF1),thereby inhibiting pancreatic islet morphogenesis and insulin synthesis in fetal rats.Furthermore,the PCE offspring after birth exhibited decreased blood CORT levels,increased H3K9 acetylation in promoter and upregulated gene expression of the pancreatic IGF1 promoter region,accompanied by elevated insulin biosynthesis.However,when exposed to chronic stress,the above changes were totally reversed.Conclusively,“glucocorticoid-insulin like growth factor 1(GC-IGF1)axis”programming may be involved in pancreaticβ-cell dysplasia and dysfunction in the PCE female offspring. 展开更多
关键词 Prenatal caffeine exposure Pancreatic development GLUCOCORTICOIDS Insulin-like growth factor 1 Intrauterine programming
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Global optimality conditions for quadratic 0-1 programming with inequality constraints 被引量:1
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作者 张连生 陈伟 姚奕荣 《Journal of Shanghai University(English Edition)》 CAS 2010年第2期150-154,共5页
Quadratic 0-1 problems with linear inequality constraints are briefly considered in this paper.Global optimality conditions for these problems,including a necessary condition and some sufficient conditions,are present... Quadratic 0-1 problems with linear inequality constraints are briefly considered in this paper.Global optimality conditions for these problems,including a necessary condition and some sufficient conditions,are presented.The necessary condition is expressed without dual variables.The relations between the global optimal solutions of nonconvex quadratic 0-1 problems and the associated relaxed convex problems are also studied. 展开更多
关键词 quadratic 0-1 programming optimality condition nonconvex optimization integer programming convex duality
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A Tabu Search Algorithm for Quadratic 0-1 Programming Problem 被引量:2
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作者 周贤伟 王远允 +1 位作者 田新现 郭瑞强 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期98-102, ,共5页
In this paper,quadratic 0-1 programming problem (I) is considered, in terms of its features quadratic 0-1 programming problem is solved by linear approxity heurstic algrothm and a developed tabu search ahgrothm .
关键词 Tabu search linear approximate quaratic 0-1 programming
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Chaotic Neural Network Technique for "0-1" Programming Problems 被引量:1
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作者 王秀宏 乔清理 王正欧 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第4期99-105,共7页
0-1 programming is a special case of the integer programming, which is commonly encountered in many optimization problems. Neural network and its general energy function are presented for 0-1 optimization problem. The... 0-1 programming is a special case of the integer programming, which is commonly encountered in many optimization problems. Neural network and its general energy function are presented for 0-1 optimization problem. Then, the 0-1 optimization problems are solved by a neural network model with transient chaotic dynamics (TCNN). Numerical simulations of two typical 0-1 optimization problems show that TCNN can overcome HNN's main drawbacks that it suffers from the local minimum and can search for the global optimal solutions in to solveing 0-1 optimization problems. 展开更多
关键词 neural network chaotic dynamics 0-1 optimization problem.
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A non-monotone Phase-1 method in linear programming 被引量:4
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作者 潘平奇 李炜 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期293-296,共4页
To gain superior computational efficiency, it might be necessary to change the underlying philosophy of the simplex method. In this paper, we propose a Phase-1 method along this line. We relax not only the conventiona... To gain superior computational efficiency, it might be necessary to change the underlying philosophy of the simplex method. In this paper, we propose a Phase-1 method along this line. We relax not only the conventional condition that some function value increases monotonically, but also the condition that all feasible variables remain feasible after basis change in Phase-1. That is, taking a purely combinatorial approach to achieving feasibility. This enables us to get rid of ratio test in pivoting, reducing computational cost per iteration to a large extent. Numerical results on a group of problems are encouraging. 展开更多
关键词 linear programming Phase-1 ratio-test-free pivoting rule
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基于双目标0-1规划的新能源汽车公共充电站桩选址布局研究
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作者 周兴建 张祖涵 艾振 《物流技术》 2025年第7期60-72,共13页
公共充电站桩作为一种面向消费者的服务设施,选址布局对新能源汽车市场发展具有重要的影响。针对当前新能源汽车公共充电站桩的网络布局和效用发挥问题,综合考虑公共充电站桩建设的公共性和经济性双重特征。首先,应用层次分析法对新能... 公共充电站桩作为一种面向消费者的服务设施,选址布局对新能源汽车市场发展具有重要的影响。针对当前新能源汽车公共充电站桩的网络布局和效用发挥问题,综合考虑公共充电站桩建设的公共性和经济性双重特征。首先,应用层次分析法对新能源汽车公共充电站桩选址影响因素进行分析,确定充电站桩服务性体现为覆盖范围(即公共性)和综合成本(即经济性)两大目标的满足上。进而,建立新能源汽车公共充电站桩选址优化双目标0-1规划模型。通过数值计算表明,相较于考虑最小综合成本目标,考虑最大覆盖范围的选址布局在同等公共充电站桩数量的条件下,公共充电站桩覆盖率增加的幅度大于年综合成本的增长幅度;同时,随着公共充电站桩数量的增加,考虑最大覆盖范围的选址布局情形下公共充电站桩的最大服务量增加幅度不断增大。研究结论为新能源汽车公共充电站桩选址决策提供参考。 展开更多
关键词 双目标 公共性 经济性 0-1规划 选址 布局 公共充电站桩 新能源汽车
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C5aR1、BDKRB1、G0S2、HIF-1α在胃癌前病变进展中的预测价值
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作者 李扬 年媛媛 孟宪梅 《包头医学院学报》 2025年第5期72-76,83,共6页
目的:探讨C5a受体(C5aR1)、缓激肽受体B1(bradykinin receptor B1,BDKRB1)、缺氧诱导因子-1α(hypoxia inducible factor-1α,HIF-1α)、G0/G1开关2(G0/G1 switch 2,G0S2)基因在肠型胃癌Correa发展模式中的表达特点,筛选胃癌前病变进展... 目的:探讨C5a受体(C5aR1)、缓激肽受体B1(bradykinin receptor B1,BDKRB1)、缺氧诱导因子-1α(hypoxia inducible factor-1α,HIF-1α)、G0/G1开关2(G0/G1 switch 2,G0S2)基因在肠型胃癌Correa发展模式中的表达特点,筛选胃癌前病变进展的预测因子。方法:选取慢性非萎缩性胃炎(chronic non-atrophic gastritis,CNAG)、慢性萎缩性胃炎(chronic atrophic gastritis,CAG)、低级别上皮内瘤变(low-grade intraepithelial neoplasia,LGIN)、高级别上皮内瘤变(high-grade intraepithelial neoplasia,HGIN)、侵及黏膜层及黏膜下层的早期胃癌(early gastric cancer,EGC)组织蜡块,应用免疫组化法检测各组织中C5aR1、BDKRB1、G0S2及HIF-1α的蛋白表达水平。结果:C5aR1主要表达于细胞膜与细胞质中,BDKRB1主要表达于细胞膜中,G0S2和HIF-1α主要表达于细胞质与细胞核中。HGIN、EGC组织中C5aR1、BDKRB1、G0S2的表达水平显著高于CAG和CNAG(P<0.001)。HGIN、EGC组织中HIF-1α表达水平显著高于CNAG(P<0.001),但与CAG相比差异无统计学意义。4个因子在LGIN与其他组织中的表达结果相比差异均无统计学意义,在CNAG和CAG组织中的表达结果相比差异无统计学意义。结论:C5aR1、BDKRB1、G0S2和HIF-1α表达量随着肠型胃癌Correa发展阶段呈增加趋势,可能具有预测胃癌前病变进展的价值。 展开更多
关键词 C5aR1 BDKRB1 G0S2 HIF-1Α 胃癌前病变
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X连锁先天性肾上腺发育不良合并NR0B1基因新发突变1例报告
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作者 陈丽丽 李雨桐 《中国优生与遗传杂志》 2025年第6期1394-1397,共4页
目的 本文报道了1例NR0B1基因突变致X连锁先天性肾上腺发育不良(X-linked AHC)病例,通过描述患者临床症状、检查结果、文献复习归纳讨论NR0B1基因突变的功能影响等,为临床诊断及治疗提供参考。方法 回顾性分析我院收治的1例X-linked AH... 目的 本文报道了1例NR0B1基因突变致X连锁先天性肾上腺发育不良(X-linked AHC)病例,通过描述患者临床症状、检查结果、文献复习归纳讨论NR0B1基因突变的功能影响等,为临床诊断及治疗提供参考。方法 回顾性分析我院收治的1例X-linked AHC患儿的临床特征及基因突变结果。结果 患儿因乏力2年、发热伴精神萎靡2日就诊,查体全身皮肤黏膜弥漫性色素沉着;基因检测明确NR0B1基因c.754C>T半合子突变致X-linked AHC。结论 X-linked AHC在临床上较为罕见的遗传性疾病,主要影响男性。其会影响许多体内的内分泌组织,尤其是肾上腺,主要特点是肾上腺皮质功能不全。该患儿的主要临床特征及基因检测结果均符合该病诊断,所以对符合该疾病临床表现的患者,应及早行基因全外显子组测序,为临床精准诊断和治疗提供依据。 展开更多
关键词 先天性肾上腺发育不良 NR0B1基因 X连锁隐性遗传 肾上腺危象 基因诊断
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虚拟仿真环境下机器人“从0到1”实验教学探索 被引量:1
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作者 段文斌 肖聚亮 +2 位作者 刘健 赵地 淮旭国 《计算机教育》 2025年第11期268-274,共7页
针对目前机器人课程教学过程中理论与实验脱节、多学科交叉融合不强等问题,分析导致问题的主要原因,提出“从0到1”的任务式实验教学方案,基于自主开发的机器人虚拟教学实验平台,以开发虚拟机器人原型机为实验任务,阐述如何将理论内容... 针对目前机器人课程教学过程中理论与实验脱节、多学科交叉融合不强等问题,分析导致问题的主要原因,提出“从0到1”的任务式实验教学方案,基于自主开发的机器人虚拟教学实验平台,以开发虚拟机器人原型机为实验任务,阐述如何将理论内容根据工程实践整合为不同的配套实验模块,通过实验应用实例介绍实验课程详细过程,最后通过教学成效说明该方案的有效性。 展开更多
关键词 虚拟仿真 机器人 “从01 实验教学
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LiFe_(x)Mn_(1-x)PO_(4)(0
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作者 吉帅静 王军伟 +6 位作者 杜宝帅 徐丽 楼平 管敏渊 汤舜 程时杰 曹元成 《储能科学与技术》 北大核心 2025年第3期965-983,共19页
在锂离子电池于电动汽车及储能领域广泛应用的背景下,磷酸锰锂铁(LiFe_(x)Mn_(1-x)PO_(4),0<x<1)作为正极材料,因其卓越的高安全性和高工作电压特性而备受瞩目。然而,LiFe_(x)Mn_(1-x)PO_(4)(LFMP)材料存在的导电性不足及循环稳... 在锂离子电池于电动汽车及储能领域广泛应用的背景下,磷酸锰锂铁(LiFe_(x)Mn_(1-x)PO_(4),0<x<1)作为正极材料,因其卓越的高安全性和高工作电压特性而备受瞩目。然而,LiFe_(x)Mn_(1-x)PO_(4)(LFMP)材料存在的导电性不足及循环稳定性较差等问题,成为制约其商业化应用的关键性障碍。针对这些问题,本文深入探讨了LFMPO4性能衰退的根源,包括Mn的Jahn-Teller畸变效应、迟缓的反应动力学以及锰基阴极材料中的歧化反应等核心问题,并深入分析了高温高压条件下产气产热的演变机制,以期揭示其失效机理。为提升LFMP的综合性能,本文总结了多种策略,如离子掺杂与碳包裹技术的结合使用、复合包覆技术以及电解质的改良等。这些策略着重于增强LFMP正极材料的电子导电性和Li^(+)迁移率,稳定其相结构以抑制由Jahn-Teller效应引发的Mn溶解,减小界面应力,并提升材料的热稳定性和安全性。通过实施上述策略,不仅验证了失效机理分析的准确性,还展望了高性能锂离子电池LFMP正极材料的未来发展趋势。结合当前的研究成果,为实现高比容量、稳定的循环性能、出色的倍率性能以及高安全性,可能需要综合运用多种手段,如碳涂层、元素掺杂以及电解质优化等,以期开发出具有高能量密度、长循环寿命和热稳定性的全电池基LFMP正极材料。此外,本文还紧密结合当前的产业化研究进展,综述了不同合成工艺与Mn掺杂比例调控对LFMP材料结构和性能的具体影响,这不仅将推动LFMP基材料在高性能锂离子电池领域的广泛应用,也为其商业化进程奠定了坚实的基础。 展开更多
关键词 LiFe_(x)Mn_(1-x)PO_(4)(01) 失效机制 JAHN-TELLER效应 掺杂改性 包覆改性 电解质策略改性
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磁记录硬盘用L1_(0)-FePt薄膜的研究进展
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作者 施晨琦 赵琪 +5 位作者 巢云秀 李思勰 沈月 许彦亭 王传军 闻明 《机械工程材料》 北大核心 2025年第6期25-31,共7页
L1_(0)-FePt薄膜因具有高磁晶各向异性、高饱和磁化强度等优良的磁学性能及良好的化学稳定性,成为下一代超高密度磁记录存储介质的最佳候选者之一。介绍了磁控溅射法、分子束处延法和化学合成法等L1_(0)-FePt薄膜制备方法,阐述了薄膜的... L1_(0)-FePt薄膜因具有高磁晶各向异性、高饱和磁化强度等优良的磁学性能及良好的化学稳定性,成为下一代超高密度磁记录存储介质的最佳候选者之一。介绍了磁控溅射法、分子束处延法和化学合成法等L1_(0)-FePt薄膜制备方法,阐述了薄膜的理想结构和性能,综述了特殊热退火处理、添加隔离介质、制备多层膜结构等3种薄膜结构调控方法,总结了真空热压法、热等静压法和放电等离子烧结法等FePt合金靶材制备工艺,指出了目前研究存在的问题,展望了高密度磁记录存储介质的发展方向。 展开更多
关键词 L1_(0)-FePt薄膜 FePt靶材 隔离介质 多层膜结构
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Prognostic value of programmed death.1, programmed death-ligand 1, programmed death-ligand 2 expression, and CD8(+) T cell density in primary tumors and metastatic lymph nodes from patients with stage T1.4N+M0 gastric adenocarcinoma 被引量:10
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作者 Yuan Gao Su Li +9 位作者 Dazhi Xu Shangxiang Chen Yuchen Cai Wenqi Jiang Xinke Zhang Jin Sun Kefeng Wang Boyang Chang Fenghua Wang Minghuang Hong 《Chinese Journal of Cancer》 SCIE CAS CSCD 2017年第11期560-573,共14页
Background: Anti-programmed death-1/programmed death-ligand 1(PD-1/PD-L1) immunotherapy has been proved to be effective on gastric cancer in ongoing clinical trials. However, the value of PD-L1 in predicting responses... Background: Anti-programmed death-1/programmed death-ligand 1(PD-1/PD-L1) immunotherapy has been proved to be effective on gastric cancer in ongoing clinical trials. However, the value of PD-L1 in predicting responses of patients with gastric cancer to anti-PD-1/PD-L1 immunotherapy is controversial. Some studies suggested that intra-and inter-tumoral heterogeneity of PD-L1 expression might explain the controversy.This study aimed to analyze the expression of PD-L1, PD-L2, and PD-1 as well as CD8(+) T-cell density in primary tumors and lymph nodes from patients with stage T1-4 N+M0 gastric adenocarcinoma to explore the heterogeneity of PD-1 signaling pathway molecules.Methods: In primary tumors and metastatic as well as non-metastatic lymph nodes from patients with stage T1-4 N+M0 gastric adenocarcinoma, we detected PD-L1 and PD-L2 expression with immunohistochemistry. CD8(+)T-cell density in primary tumors and PD-1 expression on CD8(+)T cells were detected with immunofluorescence. Univariate analysis was used to determine the prognostic values of them. Cox proportional hazard regression model was used to identify independent risk factors that affect patients' overall survival and disease-free survival.Results: Among 119 eligible patients who had undergone surgical resection, the positive rate of PD-L1 was higher in metastatic lymph nodes than in primary tumors(45.4% vs. 38.7%, P = 0.005); the positive rate of PD-1 on CD8(+)T cells was significantly higher in primary tumors and metastatic lymph nodes than in tumor-free lymph nodes(both P < 0.001). The intensity of PD-1 expression on CD8(+) T cells in primary tumors and in metastatic lymph nodes were stronger than that in tumor-free lymph nodes from the same patient. Beside, the positive rate of PD-L2 did not show any differences between primary tumors and metastatic lymph nodes. In multivariate analysis, PD-L1 expression,PD-L2 expression, a low density of CD8(+) T cells in primary tumors, and PD-1 expression on CD8(+) T cells in primary tumors were associated with poor prognosis.Conclusion: The expression of PD-L1 is heterogeneous in primary tumors and in metastatic lymph nodes from patients with stageT1-4 N+M0 gastric adenocarcinoma, which might explain the inconsistent results in assessing the prognostic value of PD-L1 expression in previous studies. 展开更多
关键词 Gastric cancer programmed CELL death-ligand 1 programmed CELL death-ligand 2 programmed CELL death-1 CD8(+) T cells Heterogeneity EXPRESSION PROGNOSTIC value
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Interleukin-17A facilitates tumor progression via upregulating programmed death ligand-1 expression in hepatocellular carcinoma 被引量:1
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作者 Zhong-Xia Yang Li-Ting Zhang +2 位作者 Xiao-Jun Liu Xue-Bin Peng Xiao-Rong Mao 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期176-198,共23页
BACKGROUND Hepatocellular carcinoma(HCC)is an inflammation-associated tumor with a dismal prognosis.Immunotherapy has become an important treatment strategy for HCC,as immunity is closely related to inflammation in th... BACKGROUND Hepatocellular carcinoma(HCC)is an inflammation-associated tumor with a dismal prognosis.Immunotherapy has become an important treatment strategy for HCC,as immunity is closely related to inflammation in the tumor microenvir-onment.Inflammation regulates the expression of programmed death ligand-1(PD-L1)in the immunosuppressive tumor microenvironment and affects im-munotherapy efficacy.Interleukin-17A(IL-17A)is involved in the remodeling of the tumor microenvironment and plays a protumor or antitumor role in different tumors.We hypothesized that IL-17A participates in tumor progression by affe-cting the level of immune checkpoint molecules in HCC.The upregulation of PD-L1 expression in HCC cells by IL-17A was assessed by reverse transcription PCR,western blotting,and flow cytometry.Mechanistic studies were conducted with gene knockout models and pathway inhibitors.The function of IL-17A in immune evasion was explored through coculture of T cells and HCC cells.The effects of IL-17A on the malignant biological behaviors of HCC cells were evaluated in vitro,and the antitumor effects of an IL-17A inhibitor and its synergistic effects with a PD-L1 inhibitor were studied in vivo.RESULTS IL-17A upregulated PD-L1 expression in HCC cells in a dose-dependent manner,whereas IL-17A receptor knockout or treatment with a small mothers against decapentaplegic 2 inhibitor diminished the PD-L1 expression induced by IL-17A.IL-17A enhanced the survival of HCC cells in the coculture system.IL-17A increased the viability,G2/M ratio,and migration of HCC cells and decreased the apoptotic index.Cyclin D1,VEGF,MMP9,and Bcl-1 expression increased after IL-17A treatment,whereas BAX expression decreased.The combination of IL-17A and PD-L1 inhibitors showed synergistic antitumor efficacy and increased cluster of differentiation 8+T lymphocyte infiltration in an HCC mouse model.CONCLUSION IL-17A upregulates PD-L1 expression via the IL-17A receptor/phosphorylation-small mothers against decapenta-plegic 2 signaling pathway in HCC cells.Blocking IL-17A enhances the therapeutic efficacy of PD-L1 antibodies in HCC in vivo. 展开更多
关键词 INTERLEUKIN-17A programmed death ligand-1 Interleukin-17A receptor Small mothers against decapentaplegic 2 Hepatocellular carcinoma IMMUNOTHERAPY
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掺杂Bi/Pb/Au/Cu促进L1_(0)-FeNi有序转变的第一性原理
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作者 王群首 唐家雨 +1 位作者 姚爽 裴文利 《东北大学学报(自然科学版)》 北大核心 2025年第10期59-65,共7页
L1_(0)有序结构的FeNi材料具有优异的磁性能,拥有广阔的应用前景.但FeNi中的L1_(0)结构形成温度低,在此温度下原子有序化扩散缓慢,导致实验中难以直接合成L1_(0)-FeNi.本文针对该问题,利用第一性原理研究了掺杂Bi,Pb,Au和Cu元素对FeNi... L1_(0)有序结构的FeNi材料具有优异的磁性能,拥有广阔的应用前景.但FeNi中的L1_(0)结构形成温度低,在此温度下原子有序化扩散缓慢,导致实验中难以直接合成L1_(0)-FeNi.本文针对该问题,利用第一性原理研究了掺杂Bi,Pb,Au和Cu元素对FeNi的有序化扩散和磁性能的影响.结果表明:掺杂第三元素可以有效改善FeNi的形成动力学,从而促进FeNi的有序转变.其中Au与Cu元素更易替位掺杂,更有利于结构的稳定性,Bi,Pb,Au和Cu更容易占据Fe位.元素的掺杂可有效降低FeNi的空位形成能,从而降低了扩散激活能,促进了Fe原子和Ni原子的扩散和转移,进而降低FeNi的无序-有序转变势垒,有效促进FeNi的有序转变.掺杂第三元素在Ni位点时对FeNi的电子结构和磁性能影响很小. 展开更多
关键词 L1_(0)-FeNi 有序转变 磁性能 扩散激活能
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0-1背包问题上界的快速计算方法 被引量:1
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作者 王正元 《火箭军工程大学学报》 2025年第1期31-40,共10页
为提高0-1背包问题上界求解的速度与精确度,分析了拉格朗日松弛方法构造的精确0-1背包问题上界模型,建立了该模型的快速求解算法,证明了精确0-1背包问题上界是拉格朗日乘子的凸函数。由此,提出了精确0-1背包问题最小上界的求解方法,证... 为提高0-1背包问题上界求解的速度与精确度,分析了拉格朗日松弛方法构造的精确0-1背包问题上界模型,建立了该模型的快速求解算法,证明了精确0-1背包问题上界是拉格朗日乘子的凸函数。由此,提出了精确0-1背包问题最小上界的求解方法,证明了精确0-1背包问题上界是物品数的单峰函数,且0-1背包问题的上界恰好等于物品数为关键物品数(关键物品数-1)时精确0-1背包问题最小上界的最大值。结果表明:该计算方法所需计算量与背包问题物品数成比例,计算速度较快,上界相对较小。通过6500例不同上界计算实验对比,提出的上界计算所需时间约为其他较优算法的15.1%;上界占优比例94.29%,而其他较优算法占优比例仅68.71%。进一步表明该上界算法可以快速构造较好的近似解,从而降低0-1背包问题的维数。 展开更多
关键词 组合优化问题 0-1背包问题 上界 精确0-1背包问题 拉格朗日松弛
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甲流感染相关肺炎患者血清YKL-40、PAR1 mRNA、PDCD5水平及其与预后的关系 被引量:1
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作者 孙雪艳 杨玉梅 +2 位作者 李阳 秦良楠 韩晶 《中华医院感染学杂志》 北大核心 2025年第11期1623-1627,共5页
目的分析甲型流感病毒感染相关肺炎患者血清几丁质酶样蛋白-40(YKL-40)、蛋白酶激活受体1(PAR1)mRNA、程序化细胞死亡分子5(PDCD5)水平,及其与预后的关系。方法选择临汾市人民医院2022年1月-2024年1月收治的951例单纯甲型流感病毒感染... 目的分析甲型流感病毒感染相关肺炎患者血清几丁质酶样蛋白-40(YKL-40)、蛋白酶激活受体1(PAR1)mRNA、程序化细胞死亡分子5(PDCD5)水平,及其与预后的关系。方法选择临汾市人民医院2022年1月-2024年1月收治的951例单纯甲型流感病毒感染患者作为甲流组,166例甲型流感病毒感染相关肺炎患者作为甲流肺炎组,同期于医院进行体检的963名健康体检者作为健康组,比较三组血清YKL-40、PAR1 mRNA、PDCD5水平;根据甲型流感病毒感染相关肺炎患者预后情况将其分为预后良好组(139例)和预后不良组(27例),比较两组血清YKL-40、PAR1 mRNA、PDCD5水平,分析三者联合对甲型流感病毒感染相关肺炎患者预后的预测价值。结果甲流肺炎组血清YKL-40、PAR1 mRNA、PDCD5水平分别为(39.41±7.85)ng/ml、(11.31±3.52)、(3.04±0.89)μg/L,高于甲流组[(28.19±5.88)ng/ml、(5.87±1.29)、(1.96±0.55)μg/L]及健康组,甲流组高于健康组(P<0.05)。预后不良组血清YKL-40、PAR1 mRNA、PDCD5水平分别为(45.73±9.63)ng/ml、(13.20±4.11)、(3.96±1.32)μg/L,高于预后良好组(P<0.05)。血清YKL-40、PAR1 mRNA、PDCD5联合预测甲型流感病毒感染相关肺炎患者预后的曲线下面积(AUC)为0.840,高于三者单独检测(P<0.05)。结论甲型流感病毒感染及其相关肺炎的发生均会引起患者血清YKL-40、PAR1 mRNA、PDCD5水平升高,且三者联合可有效提高对甲型流感病毒感染相关肺炎患者预后的预测价值。 展开更多
关键词 甲型流感病毒 感染 肺炎 几丁质酶样蛋白-40 蛋白酶激活受体1 程序化细胞死亡分子5 预后 预测价值
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Cytoplasmic and nuclear programmed death ligand 1 expression in peritumoral stromal cells in breast cancer:Prognostic and predictive value 被引量:2
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作者 Evgeniya Yu Zubareva Marina A Senchukova Natalia V Saidler 《World Journal of Experimental Medicine》 2025年第2期150-170,共21页
BACKGROUND Breast cancer(BC)continues to occupy a leading position in terms of morbidity and mortality from malignant neoplasms among the female population.One of the promising markers associated with BC progression i... BACKGROUND Breast cancer(BC)continues to occupy a leading position in terms of morbidity and mortality from malignant neoplasms among the female population.One of the promising markers associated with BC progression is programmed death ligand 1(PD-L1).Previously,we investigated PD-L1 expression in BC via a new antibody against programmed cell death protein 1 ligand 1(PDCD1 LG1)and reported that high PDCD1 LG1 expression in tumor cells is an independent factor for a high risk of regional metastasis in patients with BC.However,the prognostic significance of PDCD1 LG1 expression in BC stromal cells has not been adequately studied.AIM To study the features of PDCD1 LG1 expression in BC stromal cells and its relationship with BC clinicopathological characteristics.METHODS In a prospective single-center observational study,tumor samples from 148 patients with newly diagnosed BC were examined.The tumor sections were immunohistochemically stained with antibodies against PDCD1 LG1.In the tumor samples,the PDCD1 LG1-positive lymphocyte(PDCD1 LG1+LF)score,presence of nuclear PDCD1 LG1 expression in the LFs,PDCD1 LG1 expression in polymorphic cell infiltrates(PDCD1 LG1+polymorphic cell infiltrates[PCIs]),and cells of the fibroblastic stroma and endothelial cells of the tumor microvessels were assessed.Statistical analyses were performed using Statistica 10.0 software.RESULTS A PDCD1 LG1+LF score≥3 was detected more often at stages N0 and N3 than at N1 and N2(P=0.03).Moderate and pronounced PDCD1 LG1+PCIs and the presence of PDCD1 LG1+fibroblastic stroma were associated with negative estrogen receptor status(P=0.0008 and P=0.03,respectively),human epidermal growth factor receptor 2-positive(HER2+)BC(P<0.00001 and P=0.0005),and luminal B HER2+,non-luminal HER2+and triple-negative BC(P<0.00001 and P=0.004).The risk of metastasis to regional lymph nodes(RLNs)depend on lymphovascular invasion(LVI)and the PDCD1 LG1+LF score.In the absence of LVI and a PDCD1 LG1+LF score<3 or≥3,metastases in RLNs were absent in 66.6%and 93.9%of patients with BC,respectively.In the presence of LVI and a PDCD1 LG1+LF score<3 or≥3,metastases in RLNs were detected in 82.6%and 92.7%of patients with BC,respectively.CONCLUSION The results indicated that the combined assessment of the PDCD1 LG1+LF score and LVI can improve the accuracy of predicting the risk of metastasis to RLNs in patients with BC. 展开更多
关键词 Breast cancer programmed death-ligand 1 Regional metastasis Tumor stroma
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Concordance of programmed death-ligand 1 expression assessments determined via two immunohistochemical tests and the polymerase chain reaction method 被引量:1
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作者 Marina A Senchukova Natalia V Saidler +2 位作者 Evgeniya Yu Zubareva Alexander B Prokofiev Dmitry G Tagabilev 《World Journal of Experimental Medicine》 2025年第3期207-220,共14页
BACKGROUND We previously demonstrated that the antibody against programmed cell death protein 1 ligand 1(PDCD1 LG1)is a promising new marker of programmed death-ligand 1(PD-L1)expression that correlates with both brea... BACKGROUND We previously demonstrated that the antibody against programmed cell death protein 1 ligand 1(PDCD1 LG1)is a promising new marker of programmed death-ligand 1(PD-L1)expression that correlates with both breast cancer(BC)clinicopathological characteristics and tumor sensitivity to chemotherapy.However,the concordance of PDCD1 LG1 expression scoring with immunohistochemical(IHC)tests approved for clinical use and with the polymerase chain reaction(PCR)method has not been previously studied.AIM To evaluate the concordance of methods for assessing PD-L1 expression,IHC tests with anti-PD-L1(PDCD1 LG1)and anti-PD-L1(SP142)antibodies and PCR.METHODS This prospective single-center observational cohort study included 148 patients with BC.PD-L1 expression in immune cells was assessed by the IHC method with anti-PD-L1(PDCD1 LG1)and anti-PD-L1(SP142)antibodies and by PCR.The concordance of PD-L1 scores between tests was assessed with positive percentage agreement(PPA)and negative percentage agreement(NPA).The strength of the agreement between the methods was calculated via the Cohen kappa index.P<0.05 was considered statistically significant.RESULTS Regardless of the method used to assess marker expression,PD-L1 expression was significantly more often detected in patients with negative estrogen receptor status,human epidermal growth factor receptor-2-positive(HER2+)status,luminal B HER+BC,nonluminal HER+BC and triple-negative BC.PPA and NPA were 38.3%and 70.4%,respectively,for PD-L1(PDCD1 LG1)and PD-L1(SP142);26.3%and 63.3%,respectively,for PD-L1(PDCD1 LG1)and PD-L1(PCR);and 36.5%and 74.4%,respectively,for PD-L1(SP142)and PD-L1(PCR).Cohen's kappa index for PD-L1(PDCD1 LG1)and PD-L1(SP142)was 0.385(95%CI:0.304–0.466),that for PD-L1(PDCD1 LG1)and PD-L1(PCR)was 0.207(95%CI:0.127–0.287),and that for PD-L1(SP142)and PD-L1(PCR)was 0.389(95%CI:0.309–0.469).CONCLUSION Thus,all three markers of PD-L1 expression are associated with the characteristics of aggressive BC,demonstrating moderate concordance between the tests. 展开更多
关键词 Breast cancer Cohen kappa index Negative percentage agreement Positive percentage agreement programmed death-ligand 1 programmed cell death protein 1 ligand 1
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