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高速精密数控轧辊磨床中心架液压润滑系统的设计及其优化
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作者 朱德春 吴怀超 +2 位作者 赵丽梅 杨绿 何沐阳 《机械设计》 CSCD 北大核心 2024年第4期20-27,共8页
中心架作为轧辊磨床的重要部分之一,起着支承和卸荷的重要作用。文中以某型高速精密数控轧辊磨床为依据,设计了其中心架的液压润滑系统,基于AMESim软件建立该液压润滑系统模型并进行仿真计算,分析得出侧瓦和底瓦静压固定活塞直径、静压... 中心架作为轧辊磨床的重要部分之一,起着支承和卸荷的重要作用。文中以某型高速精密数控轧辊磨床为依据,设计了其中心架的液压润滑系统,基于AMESim软件建立该液压润滑系统模型并进行仿真计算,分析得出侧瓦和底瓦静压固定活塞直径、静压固定活塞杆径及调速阀设定流量对系统中静压腔油压特性具有显著影响。采用遗传算法对影响系统静压腔油压特性的3个参数进行优化,结果表明:优化后的中心架液压润滑系统中,静压腔油压稳定性得到了显著的改善,达到稳定状态的时间明显缩短,验证了优化方案的合理性,其结果可为轧辊磨床液压润滑系统的设计及优化研究提供理论依据。 展开更多
关键词 高速精密数控轧辊磨床 中心架 液压润滑系统 AMESIM 遗传算法 优化
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基于ALIF-LSTM多任务学习的综合能源系统短期负荷预测 被引量:8
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作者 欧阳静 杨吕 +2 位作者 尹康 赵宇航 潘国兵 《太阳能学报》 EI CAS CSCD 北大核心 2022年第9期499-507,共9页
综合能源系统中风电、光伏等可再生能源出力具有波动性和间歇性,精准的短期负荷预测有利于平抑可再生能源对系统运行的影响。系统中的多元负荷时间序列为典型的非平稳性信号,难以进行精准地预测。为了从数据层面提高综合能源系统短期负... 综合能源系统中风电、光伏等可再生能源出力具有波动性和间歇性,精准的短期负荷预测有利于平抑可再生能源对系统运行的影响。系统中的多元负荷时间序列为典型的非平稳性信号,难以进行精准地预测。为了从数据层面提高综合能源系统短期负荷预测模型的精度,提出基于自适应局部迭代滤波(ALIF)的历史负荷数据分解方法,将历史负荷序列分解为具有不同频段模态函数的多个分量;针对预测模型训练中长时间序列处理困难及系统中多元负荷间耦合信息挖掘利用的问题,建立基于长短期记忆(LSTM)网络多任务学习的综合能源系统短期负荷预测模型。实验结果显示,与LSTM、ALIF-LSTM单任务学习、随机森林、LGBM方法相比,所提方法能够应对负荷波动剧烈的工况,预测精度较高,满足综合能源系统安全稳定运行控制的要求。 展开更多
关键词 可再生能源 长短期记忆网络 多任务学习 自适应局部迭代滤波 负荷预测 综合能源系统
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碳纳米管增强Cu-Ni复合镀层制备及其性能 被引量:4
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作者 樊艳娥 杨绿 +2 位作者 张进 吴怀超 王玥 《表面技术》 EI CAS CSCD 北大核心 2019年第12期114-124,共11页
目的提升Cu-Ni复合镀层的硬度、摩擦磨损与抗腐蚀性能。方法在五水硫酸铜镀液中添加六水合硫酸镍和碳纳米管(CNT),采用电共沉积方法制备Cu-Ni、Cu-Ni/CNT复合镀层。利用显微硬度测试仪、摩擦磨损试验机测试CNT增强复合镀层(Cu-Ni/CNT)... 目的提升Cu-Ni复合镀层的硬度、摩擦磨损与抗腐蚀性能。方法在五水硫酸铜镀液中添加六水合硫酸镍和碳纳米管(CNT),采用电共沉积方法制备Cu-Ni、Cu-Ni/CNT复合镀层。利用显微硬度测试仪、摩擦磨损试验机测试CNT增强复合镀层(Cu-Ni/CNT)的硬度和摩擦磨损性能。借助扫描电子显微镜(SEM)、能谱仪(EDS)表征镀层的表面形貌、元素分布及磨斑表面特征。在模拟海水(3.5%NaCl)溶液中测试镀层的电化学阻抗谱(Nyquist)和Tafel曲线。结果Ni、Cu共沉积时,更多Ni原子被Cu原子置换,镀层硬度相比于纯镍镀层略有下降,但是Cu-Ni固溶体形成后固溶强化使耐磨损性增强。CNT共沉积镶嵌在Cu-Ni复合镀层中,其晶粒细化和弥散强化效应使镀层硬度提高,在考察范围内,最高达到560.59HV。当Cu-Ni共沉积镀液中加入0.08%(质量分数)CNT时,复合镀层中CNT的物理屏蔽使其具有最高的腐蚀电位(-436.08 mV)、最低的自腐蚀速率与最好的抗腐蚀性能,其镀层电阻(Rc)为1573Ω·cm2;相比于纯Ni镀层,腐蚀抑制效率为95.86%;镀层平均摩擦系数最低,为0.52,耐磨性最佳。结论共沉积时,适当配比CNT的加入可有效增强Cu-Ni复合镀层的硬度、摩擦磨损性能和抗腐蚀性能。 展开更多
关键词 电沉积 CNT Cu-Ni复合镀层 显微硬度 摩擦磨损性能 抗腐蚀性能 电化学阻抗谱
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血管紧张素转换酶2在新型冠状病毒肺炎(COVID-19)发病机制及治疗中的作用研究进展 被引量:7
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作者 杨吕 何庆 《中国药理学与毒理学杂志》 CAS 北大核心 2020年第8期575-583,共9页
新型冠状病毒(SARS-CoV-2)感染导致严重的急性呼吸系统病变,其临床表现和肺部病理特征与急性肺损伤和急性呼吸窘迫综合征相似。已有研究表明,血管紧张素转换酶2(ACE2)为SARS冠状病毒(SARS-CoV)的功能受体。最近发现,SARS-CoV-2也可通过... 新型冠状病毒(SARS-CoV-2)感染导致严重的急性呼吸系统病变,其临床表现和肺部病理特征与急性肺损伤和急性呼吸窘迫综合征相似。已有研究表明,血管紧张素转换酶2(ACE2)为SARS冠状病毒(SARS-CoV)的功能受体。最近发现,SARS-CoV-2也可通过与细胞表面ACE2结合感染细胞,导致细胞病变和组织免疫损伤。人ACE2虽然是人ACE的同源物,但作为一种新型的金属羧肽酶,很多特性与ACE不同。ACE2在肾素-血管紧张素系统中具有独特的作用,参与维持肺的正常功能。ACE2是新型冠状病毒肺炎(COVID-19)病理途径中的关键因子,在COVID-19的临床治疗和药物研制中具有重要意义。 展开更多
关键词 血管紧张素转换酶2 S蛋白 新型冠状病毒肺炎 急性肺损伤
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SMILE术后视觉质量的研究进展 被引量:8
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作者 魏新龙 吕洋 +1 位作者 郑鑫 岳红云 《国际眼科杂志》 CAS 北大核心 2022年第7期1113-1117,共5页
飞秒激光小切口角膜基质透镜取出术(SMILE)是目前最先进的角膜屈光手术之一。与传统角膜屈光手术不同,SMILE手术实现了微创和无瓣。因此,SMILE术后视觉质量的评估也具有特点,目前国内外最新研究证实SMILE术后裸眼视力可显著提高且术后... 飞秒激光小切口角膜基质透镜取出术(SMILE)是目前最先进的角膜屈光手术之一。与传统角膜屈光手术不同,SMILE手术实现了微创和无瓣。因此,SMILE术后视觉质量的评估也具有特点,目前国内外最新研究证实SMILE术后裸眼视力可显著提高且术后屈光状态稳定,但对SMLIE术后高阶像差、调制传递函数截止频率(MTF cut off)、客观散射指数(OSI)等客观视觉质量指标及其影响因素的认识却不尽相同。本文针对SMILE术后视觉质量及其影响因素进行综述,为临床提供帮助。 展开更多
关键词 飞秒激光小切口角膜基质透镜取出术(SMILE) 视觉质量 波阵面像差 调制传递函数截止频率 客观散射指数 影响因素
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胃癌不同部位特征和预后的对比分析及临床意义 被引量:3
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作者 韩涛 夏文彬 +2 位作者 吕扬 梁寒 王东浩 《中国肿瘤临床》 CAS CSCD 北大核心 2020年第23期1200-1204,共5页
目的:探讨胃癌不同部位的临床特点差异及预后的不同。方法:分析2010年1月至2014年12月于天津医科大学肿瘤医院行胃癌根治术的患者,按照肿瘤部位分为胃上部癌组、胃中部癌组、胃下部癌组、多部位癌组,对比各组患者性别构成比、年龄、Borr... 目的:探讨胃癌不同部位的临床特点差异及预后的不同。方法:分析2010年1月至2014年12月于天津医科大学肿瘤医院行胃癌根治术的患者,按照肿瘤部位分为胃上部癌组、胃中部癌组、胃下部癌组、多部位癌组,对比各组患者性别构成比、年龄、Borrmann分型、肿瘤最大径、病理类型、TNM分期、临床分期、软组织转移情况等临床特点及预后。结果:481例患者总体1、3、5年生存率分别为77.1%、46.0%和31.0%。各组患者生存率差异均具有统计学意义(均P<0.05)。临床特点方面,各组患者在性别构成比(P<0.001)、Borrmann分型(P<0.001)、病理类型(P=0.001)、肿瘤最大径(P<0.001)、T分期(P<0.001)、N分期(P<0.001)、临床分期(P<0.001)、淋巴结外软组织转移(P<0.001)方面差异均具有统计学意义;在年龄(P=0.260)、M分期(P=0.189)方面差异无统计学意义。结论:不同部位胃癌的临床特点和预后均具有显著性差异,临床中需根据患者情况开展个体化治疗。 展开更多
关键词 胃癌 部位 生存期 临床特点 预后
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Effect of integrin α5β1 inhibition on SDF-l/CXCR4-mediated choroidal neovascularization 被引量:2
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作者 yang lyu Wen-Qin Xu +3 位作者 Li-Juan Sun Xiao-Yan Pan Jian Zhang Yu-Sheng Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第5期726-735,共10页
AIM:To investigate the roles of integrins in choroidal neovascularization(CNV) and their associations with the stromal cell-derived factor-1(SDF-1)/CXCR4 axis.METHODS:CNV lesions were induced in mice using laser... AIM:To investigate the roles of integrins in choroidal neovascularization(CNV) and their associations with the stromal cell-derived factor-1(SDF-1)/CXCR4 axis.METHODS:CNV lesions were induced in mice using laser photocoagulation.After CNV induction,all animals were randomly assigned to:control,SDF-1,SDF-1+age-related macular degeneration(AMD) 3100(CXCR4 inhibitor),and SDF-1+ATN161(integrin α5β1 inhibitor) groups;their effects on CNV progression were observed using hematoxylin eosin(HE) staining,fundus fluorescein angiography(FFA) grading and optical coherence tomography(OCT),and their effects on CXCR4/integrin α5 expression were evaluated using Western blot and double immunofluorescence staining.Hypoxia-exposed endothelial cells(ECs) were used to simulate CNV in vitro,they were treated with SDF-1,combined with CXCR4 siRNA/AMD3100 or ATN161,and expression of integrin α5,cell migration and tube formation were analyzed.RESULTS:Integrin subunit α5 increased at 3^ rd and 7^ th day and decreased at 14 ^th day in CNV mice,with no significant change of β1-integrin.CXCR4 expression in CNV mice had persistent increase within 14 d after induction.SDF-1 treatment significantly promoted the CNV progression during 3-14 d.The mean CNV length in AMD3100 andATN161 group at day 7 was 270.13 and 264.23 μm in HE images,significantly lower than the mean length in SDF-1(345.70 μm) group.AMD3100 and ATN161 also significantly reduced thickness and leakage of CNV induced by SDF-1.Mean integrin α5 positive area in SDF-1 group reached 2.31×104 μm^2,significantly higher than control(1.25×104 μm^2),which decreased to 1.78×104 μm^2 after AMD3100 treatment.About 61.36% of ECs in CNV lesions expressed α5 in SDF-1 group,which significantly decreased to 43.12% after AMD3100 treatment.In vitro,integrin α5 peaked by 6 folds after 6 h of hypoxia exposure and CXCR4 gradually increased by up to 2.3 folds after 24 h of hypoxia.Approximately 25.12% of ECs expressed integrin α5 after SDF-1 stimulation,which decreased to 7.2%-9.5% after si-CXCR4 or AMD3100 treatment.ATN161 exerted an inhibitory effect comparable to that of si-CXCR4 on EC migration and tube formation in the presence of SDF-1.CONCLUSION:SDF-1/CXCR4 signaling induces integrin α5β1 expression in ECs to promote CNV. 展开更多
关键词 choroidal neovascularization endothelial cells stromal cell-derived factor-1 CXCR4 integrin α5β1 HYPOXIA
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In vivo bioluminescence imaging of hyperglycemia exacerbating stem cells on choroidal neovascularization in mice 被引量:2
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作者 Xiang Gao Yu Wang +6 位作者 Hui-Yuan Hou yang lyu Hai-Yan Wang Li-Bo Yao Jian Zhang Feng Cao Yu-Sheng Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第4期519-527,共9页
AIM: To investigate the influence of hyperglycemia on the severity of choroidal neovascularization(CNV),especially the involvement of bone marrow-derived cells(BMCs) and underlying mechanisms.·METHODS: BMCs... AIM: To investigate the influence of hyperglycemia on the severity of choroidal neovascularization(CNV),especially the involvement of bone marrow-derived cells(BMCs) and underlying mechanisms.·METHODS: BMCs from firefly luciferase(Fluc)/green fluorescent protein(GFP) double transgenic mice were transplanted into C57BL/6J wide-type mice. The recipient mice were injected intraperitoneally with streptozotocin(STZ) daily for 5 consecutive days to induce diabetes mellitus(DM), followed by CNV laser photocoagulation.The BMCs recruitment in CNV exposed to hyperglycemia was firstly examined in Fluc/GFP chimeric mice by in vivo optical bioluminescence imaging(BLI) and in vitro Fluc assays. The CNV severity was evaluated by H&E staining and choroidal flatmount. The expression of vascular endothelial growth factor(VEGF) and stromal cell derived factor-1(SDF-1) was detected by Western blot.·RESULTS: BLI showed that the BMCs exerted dynamic effects in CNV model in Fluc/GFP chimeric mice exposed to hyperglycemia. The signal intensity of transplanted Fluc+GFP+BMCs in the DM chimeric mice was significantly higher than that in the control chimeric mice with CNV induction at days 5, 7, 14 and 21(121861.67 ±9948.81 vs 144998.33 ±13787.13 photons/second/cm2/sr for control and DM mice, P5d〈0.05; 178791.67±30350.8 vs240166.67 ±22605.3, P7d〈0.05; 124176.67 ±16253.52 vs196376.67 ±18556.79, P14d〈0.05; 97951.60 ±10343.09 vs119510.00 ±14383.76, P21d〈0.05), which was consistent with in vitro Fluc assay at day 7 [relative light units of Fluc(RLU1)], 215.00±52.05 vs 707.33±88.65, P 〈0.05; RLU1/relative light units of renilla luciferase(RLU2), 0.90 ±0.17 vs 1.83 ±0.17, P 〈0.05]. The CNVs in the DM mice were wider than those in the control group at days 5, 7, 14 and21(147.83±17.36 vs 220.33±20.17 μm, P5d〈0.05; 212.17 ±24.63 vs 326.83 ±19.49, P7d〈0.05; 163.17 ±18.24 vs265.17 ±20.55, P14d〈0.05; 132.00 ±10.88 vs 205.33 ±12.98,P21d〈0.05). The average area of CNV in the DM group was larger at 7d(20688.67±3644.96 vs 32218.00±4132.69 μm2,P 〈0.05). The expression of VEGF and SDF-1 was enhanced in the DM mice.·CONCLUSION: Hyperglycemia promots the vasculo-genesis of CNV, especially the contribution of BMCs,which might be triggered by VEGF and SDF-1 production. 展开更多
关键词 hyperglycemia choroidal neovascularization bone marrow-derived cells molecular imaging in vivo optical bioluminescence imaging
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重症患者标准化查房:思考与探索
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作者 周然 尹万红 +3 位作者 杨吕 王小亭 晁彦公 何伟 《中华内科杂志》 CAS CSCD 北大核心 2024年第5期434-438,共5页
重症学科和重症患者的特点,决定了对重症患者的救治需要更高质量的查房;正确的指导思想、标准而细致的步骤设定有助于全面、高效地查房,提高救治效率和质量。现结合笔者团队的实践经验,基于“辨析重症”及明确重症机制等核心环节,分别... 重症学科和重症患者的特点,决定了对重症患者的救治需要更高质量的查房;正确的指导思想、标准而细致的步骤设定有助于全面、高效地查房,提高救治效率和质量。现结合笔者团队的实践经验,基于“辨析重症”及明确重症机制等核心环节,分别从如何按照“五环节架构”进行查房前临床信息采集,如何设定查房时各角色的工作内容,如何在查房后诊疗计划的实施阶段进行任务分配和治疗考核等几方面,论述重症查房的内容、目的、人员和实施方法等,为高质量查房提供参考。 展开更多
关键词 查房 标准化 重症画像 五环节架构 层次化治疗 多团队协作
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Novel Ring Compression Test Method to Determine the Stress-Strain Relations and Mechanical Properties of Metallic Materials
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作者 Guangzhao Han Lixun Cai +4 位作者 Chen Bao Bo Liang yang lyu Maobo Huang Xiaokun Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第6期114-125,共12页
Although there are methods for testing the stress-strain relation and strength,which are the most fundamental and important properties of metallic materials,their application to small-volume materials and tube compone... Although there are methods for testing the stress-strain relation and strength,which are the most fundamental and important properties of metallic materials,their application to small-volume materials and tube components is lim-ited.In this study,based on energy density equivalence,a new dimensionless elastoplastic load-displacement model for compressed metal rings with isotropy and constitutive power law is proposed to describe the relations among the geometric dimensions,Hollomon law parameters,load,and displacement.Furthermore,a novel test method was developed to determine the elastic modulus,stress-strain relation,yield and tensile strength via ring compression test.The universality and accuracy of the method were verified within a wide range of imaginary materials using finite element analysis(FEA),and the results show that the stress-strain curves obtained by this method are consistent with those inputted in the FEA program.Additionally,a series of ring compression tests were performed for seven metallic materials.It was found that the stress-strain curves and mechanical properties predicted by the method agreed with the uniaxial tensile results.With its low material consumption,the ring compression test has the potential to be as an alternative to traditional tensile test when direct tension method is limited. 展开更多
关键词 Ring compression Energy density equivalence Stress-strain relation STRENGTH Metallic material
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Salvianolic acid A attenuates vascular remodeling in pulmonary arterial hypertension rats induced by monocrotaline
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作者 Lian-hua FANG Yu-cai CHEN +2 位作者 Tian-yi YUAN yang lyu Guan-hua DU 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期279-280,共2页
OBJECTIVE Salvianolic acid A(SAA) is one of the most bioactive compounds from a traditional Chinese medicine called Dan Shen(Salvia Miltiorrhiza Bunge) and exhibits many pharmaco.logical activities.Previous studies ha... OBJECTIVE Salvianolic acid A(SAA) is one of the most bioactive compounds from a traditional Chinese medicine called Dan Shen(Salvia Miltiorrhiza Bunge) and exhibits many pharmaco.logical activities.Previous studies have indicated that SAA may inhibit endothelial dysfunction and vascular remodeling in spontaneously hypertensive rats.However,whether SAA improves vascular remodeling induced by pulmonary arterial hypertension(PAH) remains unknown.In this study we examined whether SAA attenuated vascular remodeling in a PAH rat induced by monocrotaline(MCT),and elucidated the underlying mechanisms.METHODS PAH was induced in rats by injecting a single dose of monocrotaline(MCT 60 mg·kg^(-1)).The rats were orally treated with either SAA(0.3,1,3 mg·kg^(-1)·d^(-1)) or a positive con.trol Bosentan(30 mg·kg^(-1)·d^(-1)) for 4 weeks.Echocardiography and hemodynamic measurements were performed on d 28.Then the hearts and lungs were harvested,the organ indices and pulmonary artery wall thickness were calculated,and biochemical and histochemical analysis were conducted.The levels of apoptotic and signaling proteins in the lungs were measured using immunoblotting.RESULTS Treatment with SAA effectively ameliorated MCT-induced pulmonary artery remodeling,pulmonary hemodynamic ab.normalities and the subsequent increases of right ventricular systolic pressure(RVSP).Furthermore,the treatments significantly attenuated MCT-induced hypertrophic damage of myocardium,parenchymal in.jury and collagen deposition in the lungs.Moreover,the treatments attenuated MCT-induced apoptosis and fibrosis in the lungs.The treatments partially restored MCT-induced reductions of bone morphoge.netic protein type Ⅱ receptor(BMPR Ⅱ) and phosphorylated Smad1/5 in the lungs.CONCLUSION SAA ameliorates the pulmonary arterial remodeling in MCT-induced PAH rats most likely via activating the BMPRII-Smad pathway and inhibiting apoptosis.Thus,SAA may have therapeutic potential for the pa.tients at high risk of PAH. 展开更多
关键词 丹酚酸 中药 丹参 治疗方法
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Total flavonoids of bugloss limits left ventricular remodeling after myocardial infarction in mice
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作者 Shou-bao WANG Dan-shu WANG +4 位作者 Yi-huang LIN Rong-rong WANG Lian-hua FANG yang lyu Guan-hua DU 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期306-306,共1页
OBJECTIVE To investigate the effects of total flavonoids of bugloss(TFB) on left ventricular(LV) remodeling after myocardial infarction(MI),LV size and function was compared in mice subjected to left anterior descendi... OBJECTIVE To investigate the effects of total flavonoids of bugloss(TFB) on left ventricular(LV) remodeling after myocardial infarction(MI),LV size and function was compared in mice subjected to left anterior descending coronary artery ligation.METHODS 28 d after MI,the infarcted fraction of the LV and LV mass,systolic and diastolic function were measured.Capillary density and myocyte width in the nonischemic portion of the LV were also determined.RESULTS 28 d after MI,both groups had dilated LVs with decreased fractional shortening and lower ejection fractions.Although the infarcted size of the LV was similar in both groups,LV end-diastolic internal diameter,end-diastolic volume,and mass were lower,but fractional shortening,ejection fraction,and the maximum rate of developed LV pressure(dp/dtmax) were greater in TFB treated mice than in control mice.Impairment of diastolic func.tion,as measured by the time constant of isovolumic relaxation(t) and the maximum rate of LV pres.sure decay(dp/dtmin),was more marked in control mice than in TFB treated mice.Mortality after MI was greater in control mice than in TFB treated mice.In control mice,capillary density and myocyte width in the nonischemic portion of the LV did not differ before and 28 days after MI,whereas in TFB treated mice,capillary density increased and myocyte width declined after MI.CONCLUSION These results suggest that the presence of TFB limits LV dysfunction and remodeling in a murine model of MI in part by decreasing myocyte hypertrophy in the remote myocardium. 展开更多
关键词 黄酮 心肌梗塞 治疗方法 临床分析
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Activation of Nrf2 attenuates pulmonary vascular remodeling via inhibiting endothelial-to-mesenchymal transition
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作者 Yu-cai CHEN Tian-yi YUAN +3 位作者 Di CHEN Lian-hua FANG yang lyu Guan-hua DU 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期275-276,共2页
OBJECTIVE To investigate the pharmacological effect and mechanism of Salvianolic acid A(SAA) on pulmonary vascular remodeling.METHODS In current study,we conducted a series of experiments to clarify the effect of SAA,... OBJECTIVE To investigate the pharmacological effect and mechanism of Salvianolic acid A(SAA) on pulmonary vascular remodeling.METHODS In current study,we conducted a series of experiments to clarify the effect of SAA,a kind of polyphenol compound,in the process of EndMT in human pulmonary arterial endothelial cells and in vivo therapeutic efficacy on vascular remodeling in monocrotaline(MCT)-induced EndMT.EndMT was also induced by TGF-β1 in human pulmonary arterial endothelial cells(HPAECs) in vitro.RESULTS SAA significantly attenuated EndMT,simul.taneously inhibited cell migration and reactive oxygen species(ROS) formation.In MCT-induced pulmonary arterial hypertension(PAH) model,SAA improved vascular function,decreased TGF-β1 level and inhib.ited inflammation.Mechanistically,SAA stimulated Nrf2 translocation and subsequent heme oxygen.ase-1(HO-1) up-regulation.The effect of SAA on EndMT in vitro was abolished by ZnPP,a HO-1 inhibitor.CONCLUSION This study indicates a deleterious impact of oxidative stress on EndMT.Polyphenol antioxidant treatment may provide an adjunctive action to alleviate pulmonary vascular remodeling via inhibiting EndMT. 展开更多
关键词 丹酚酸 肺血管 药理作用 药物分析
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特发性肺纤维化患者患病体验的研究
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作者 吕扬 贾燕瑞 +2 位作者 高凤莉 Ya-Ling Huang Frances Lin 《International Journal of Nursing Sciences》 CSCD 2021年第2期175-180,I0003,共7页
目的探讨特发性肺纤维化(idiopathic pulmonary fibrosis,IPF)患者患病的真实体验及其护理需求。方法采用面对面半结构式访谈收集资料。采用目的抽样法选取北京市某三级医院呼吸内科住院的16例IPF患者。访谈资料采用专题分析方法进行分... 目的探讨特发性肺纤维化(idiopathic pulmonary fibrosis,IPF)患者患病的真实体验及其护理需求。方法采用面对面半结构式访谈收集资料。采用目的抽样法选取北京市某三级医院呼吸内科住院的16例IPF患者。访谈资料采用专题分析方法进行分析。结果共获得四个主题,包括确诊过程漫长、与疾病共存、了解疾病与治疗的需求、对延续护理的需求。并提炼出一系列子主题,包括诊断的不确定性和延迟,存在多种身体症状和情绪困扰,失去自主性,对疾病预后不确定,对疾病原因和治疗的不良反应有疑问,缺乏连续性的护理,希望社区医院能有更好的医疗质量。结论根据研究结果,迫切需要改善对这一弱势群体的护理服务。为了满足患者的健康需求,有必要为IPF患者制订有效的教育计划;特别是在偏远地区,应注重改善卫生保健系统护理模式,以提高护理服务的连续性。 展开更多
关键词 卫生服务需求 特发性纤维化 病人 定性研究
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Printable,flexible ceramic fiber paper based on electrospinning
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作者 Yong-Shuai Xie Yuan Cheng +2 位作者 yang lyu Rui Li Jie-Cai Han 《Rare Metals》 SCIE EI CAS CSCD 2024年第6期2739-2746,共8页
Based on the fact that it is challenging for the polymer flexible circuit substrates to meet the requirements of serving in high-temperature environments,this work proposed the idea of using printable ceramic fiber pa... Based on the fact that it is challenging for the polymer flexible circuit substrates to meet the requirements of serving in high-temperature environments,this work proposed the idea of using printable ceramic fiber paper as a high-temperature flexible circuit substrate.A ceramic fiber paper with all ceramic components had been developed via electrospinning,solving the problems of low strength and severe strength drop at high temperatures of traditional ceramic fiber paper.The tensile strength of the prepared ceramic fiber paper is 2.63 MPa,and the reliable service temperature is 1200℃.Its bulk density is about 1.5 times that of traditional ceramic fiber paper.It can be printed with patterns by commercial inkjet printers like ordinary printing paper and has excellent printability.The feasibility of ceramic fiber paper as a flexible circuit substrate was verified by constructing a simple circuit.When the fiber paper is significantly bent,the circuit still forms a complete path,which proves that it has a strong application potential for high-temperature flexible circuit substrate and is expected to promote the development of flexible electronic devices serving at extreme high-temperature environments. 展开更多
关键词 Ceramic fiber paper High temperature Inkjet printing Flexible electronic
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Green intelligent fertilizers——A novel approach for aligning sustainable agriculture with green development
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作者 Maoying WANG Lingyun CHENG +8 位作者 Chengdong HUANG yang lyu Lin ZHANG Zhenya LU Changzhou WEI Wenqi MA Zed RENGEL Jianbo SHEN Fusuo ZHANG 《Frontiers of Agricultural Science and Engineering》 CSCD 2024年第1期186-196,共11页
This review addresses the growing disparity between the current state of fertilizer production in China and the evolving demands of green agriculture in the 21st century. It explores major advances in fertilizers, pro... This review addresses the growing disparity between the current state of fertilizer production in China and the evolving demands of green agriculture in the 21st century. It explores major advances in fertilizers, proposes the concept of green intelligent fertilizers and develops new strategies aligned with the principles of green development in fertilizer industry and agriculture.Green intelligent fertilizers may be designed to maximize the synergistic effects among plants, soils, microorganisms, nutrient sources and the environment. This concept emphasizes the integration of industry and agriculture toward green development for entire industry chain, using an interdisciplinary approach to drive the green transformation of fertilizer industry, and promote green and sustainable development of agriculture. By bridging the gap between the current state of fertilizer industry and a growing need for environmentally responsible agricultural practices, this review highlights a path toward harmonizing fertilizer production with the imperatives of green agriculture. 展开更多
关键词 Root-nutrient feedback green development intelligent fertilizers new fertilizer plant-soil-fertilizer interaction rhizosphere engineering
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公立医院成本管控的案例与启示——以国药医疗为例
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作者 杨珊华 周震宇 +2 位作者 邱秋里 吕阳 陈硕 《中国管理会计》 2024年第3期34-44,共11页
伴随着我国医保支付制度改革的不断深入,药耗零加成、疾病诊断相关分组(DRG)支付方式改革等政策相继实施,公立医院承受越来越大的运营压力,如何开展成本精益化管控、实现管理转型是公立医院亟待解决的问题。本文从国药医疗所属公立医院... 伴随着我国医保支付制度改革的不断深入,药耗零加成、疾病诊断相关分组(DRG)支付方式改革等政策相继实施,公立医院承受越来越大的运营压力,如何开展成本精益化管控、实现管理转型是公立医院亟待解决的问题。本文从国药医疗所属公立医院中选取本量利模型、提质增效项目制和DRG综合分析模型三个成本管控典型案例,总结其成本管控经验,进而为公立医院成本管控提供实践参考。 展开更多
关键词 公立医院 成本管控 本量利模型 提质增效项目制 DRG模型
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急性呼吸循环障碍的改良七步法分析及治疗流程 被引量:1
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作者 周然 尹万红 +3 位作者 杨吕 王小亭 晁彦公 何伟 《中华内科杂志》 CAS CSCD 北大核心 2023年第12期1423-1429,共7页
急性呼吸循环障碍是最常见的重症综合征,其实质是以心肺为核心的器官/系统受损,是疾病和损伤进入重症阶段的基本表现。其发生发展包含以下几个环节:个体的特殊性、原发疾病打击、机体反应失调及全身性紊乱。因此,急性呼吸循环障碍的诊... 急性呼吸循环障碍是最常见的重症综合征,其实质是以心肺为核心的器官/系统受损,是疾病和损伤进入重症阶段的基本表现。其发生发展包含以下几个环节:个体的特殊性、原发疾病打击、机体反应失调及全身性紊乱。因此,急性呼吸循环障碍的诊治是临床难题。根据既往提出的基于重症超声的病理生理导向的急性呼吸循环事件管理流程(PIEPEAR),结合近年的临床实践经验,总结了改良的七步法分析及治疗流程,有助于引导临床医生对急性呼吸循环障碍时的合理思考及规范治疗。该流程包括:基于临床问题的辨析、目的性临床信息追加获取、基于重症超声的床旁核心病情评估、病理生理紊乱及机体反应表型分析、病因诊断、分层一体化治疗、两层三面的治疗效果反馈。通过"庖丁解牛"式的思维引导和可视化监测,强化临床问题辨析及围绕病理生理紊乱、机体反应及原发病因三位一体的诊疗分析思路,以更准确地厘清病情关键节点,使治疗更具针对性和简单,达到"升维认知、降维治疗"的目的。 展开更多
关键词 急性呼吸循环障碍 改良七步法 可视化 流程
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无人机系统自主安全:定义、建模与分级
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作者 潘泉 郭亚宁 +2 位作者 吕洋 李扬 谈政 《中国科学:信息科学》 CSCD 北大核心 2023年第8期1608-1628,共21页
自主与安全平衡是无人机技术与产业健康、快速发展的战略需求和核心关键.在同时面对“不断提升的无人自主飞行性能”与“日趋严峻的物理、信息、智能等多域安全威胁”的挑战下,仅借鉴有人机安全体系,适度拓展适航飞行和感知规避为核心... 自主与安全平衡是无人机技术与产业健康、快速发展的战略需求和核心关键.在同时面对“不断提升的无人自主飞行性能”与“日趋严峻的物理、信息、智能等多域安全威胁”的挑战下,仅借鉴有人机安全体系,适度拓展适航飞行和感知规避为核心的安全架构已不能满足现在和未来无人机系统的安全需求,构建无人机自主安全新架构显得十分必要和迫切.本文从自主性这一无人机固有的本质属性出发,初步研究了无人机自主安全架构,重点定义和表征了“无人机自主安全”新概念、构建了面向多域安全威胁和系统高度自主的无人机系统自主安全新模型、提出了无人机系统自主安全能力分级,为我国无人机行业健康快速发展提供基础支撑,为其他无人系统安全体系建立提供借鉴. 展开更多
关键词 无人机系统 多域威胁 自主安全 资源配置
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Efficient fabrication of light Cf/SiHfBOC composites with excellent thermal shock resistance and ultra-high-temperature ablation up to 1800℃
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作者 yang lyu Zhihong Han +5 位作者 Guangdong Zhao Yuan Cheng Shanbao Zhou Xinghong Zhang Guiqing Chen Wenbo Han 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2023年第11期2062-2074,共13页
In this paper,a high-yield Hf-modified SiHfBOC ceramic precursor was developed,and a high-pressure assisted impregnation pyrolysis method was proposed to achieve the preparation of 3D PyC–Cf/SiHfBOC composites.This h... In this paper,a high-yield Hf-modified SiHfBOC ceramic precursor was developed,and a high-pressure assisted impregnation pyrolysis method was proposed to achieve the preparation of 3D PyC–Cf/SiHfBOC composites.This high-pressure assisted impregnation method significantly improves impregnation filling effect of the precursor in and between fiber bundles compared to dozens of traditional impregnation cycles.After undergoing just 9 precursor infiltration pyrolysis(PIP)cycles,the composites achieved relative density of approximately 90%and density of 1.64 g/cm^(3).The critical temperature difference of the 3D PyC–Cf/SiHfBOC composites after the shock of room temperature(RT)–1000℃is as high as 650℃,which is twice that of traditional ceramic materials,showing good thermal shock resistance.Under the effect of Hf modification,a dense HfO_(2)–SiO_(2)oxide layer(thickness of 93μm)was formed in situ on the surface of the 3D PyC–Cf/SiHfBOC composites,effectively preventing further erosion of the composite matrix by high-temperature oxidation gas.Even in the ultra-high-temperature oxygen-containing environment at 1800℃,it still exhibits an excellent non-ablative result(with a linear ablation rate of 0.83×10^(−4)mm/s).This work not only enriches the basic research on lightweight ultra-high-temperature ceramic composites converted from Hf ceramic precursors,but also provides strong technical support for their applications in ultra-high-temperature non-ablative thermal protection materials for high-speed aircraft. 展开更多
关键词 3D PyC-C/SiHfBOC composites precursor infiltration pyrolysis(PIP)method thermal shock resistance ablation resistance ablation mechanism
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