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Design,test,and verification of in-situ condition preserved coring and analysis system in lunar-based simulation environment 被引量:1
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作者 Haichun Hao Mingzhong Gao +10 位作者 Yan Wu Zheng Gao Yongcheng Li Xuemin Zhou Peng Chu xuan wang Jiahua Li Lang Zhou Jie Song Tianxiang Ao Yikun Yang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1259-1272,共14页
The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and soci... The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and society.Technological exploration and research in the field of deep space science,especially lunar-based exploration,is a scientific strategy that has been pursued in China and worldwide.Drilling and sampling are key to accurate exploration of the desirable characteristics of deep lunar resources.In this study,an in-situ condition preserved coring(ICP-Coring)and analysis system,which can be used to test drilling tools and develop effective sampling strategies,was designed.The key features of the system include:(1)capability to replicate the extreme temperature fluctuations of the lunar environment(-185 to 200℃)with intelligent temperature control;(2)ability to maintain a vacuum environment at a scale of 10^(-3) Pa,both under unloaded conditions within Ф580 mm×1000 mm test chamber,and under loaded conditions using Ф400 mm×800 mm lunar rock simulant;(3)application of axial pressures up to 4 MPa and confining pressures up to 3.5 MPa;(4)sample rotation at any angle with a maximum sampling length of 800 mm;and(5)multiple modes of rotary-percussive drilling,controlled by penetration speed and weight on bit(WOB).Experimental studies on the drilling characteristics in the lunar rock simulant-loaded state under different drill bit-percussive-vacuum environment configurations were conducted.The results show that the outgassing rate of the lunar soil simulant is greater than that of the lunar rock simulant and that a low-temperature environment contributes to a reduced vacuum of the lunar-based simulated environment.The rotary-percussive drilling method effectively shortens the sampling time.With increasing sampling depth,the temperature rise of the drilling tools tends to rapidly increase,followed by slow growth or steady fluctuations.The temperature rise energy accumulation of the drill bits under vacuum is more significant than that under atmospheric pressure,approximately 1.47 times higher.The real-time monitored drilling pressure,penetration speed and rotary torque during drilling serve as parameters for discriminating the drilling status.The results of this research can provide a scientific basis for returning samples from lunar rock in extreme lunar-based environments. 展开更多
关键词 Lunar-based Large temperature difference Vacuum Drilling and coring System design
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Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution 被引量:1
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作者 xuan wang Akang Chen +3 位作者 XinLei Wu Jiatao Zhang Jichen Dong Leining Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期49-94,共46页
In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterpart... In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterparts.The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications.In this context,the atomic substitution method has emerged as a favorable approach.It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting materials.In this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC materials.The effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are discussed.The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these advancements.Finally,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized. 展开更多
关键词 Transition metal chalcogenides Atomic substitution Ion exchange Low-dimensional materials Controllable synthesis
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Demonstration of a small‐scale power generator using supercritical CO_(2) 被引量:1
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作者 Ligeng Li Hua Tian +7 位作者 Xin Lin Xianyu Zeng Yurong wang Weilin Zhuge Lingfeng Shi xuan wang Xingyu Liang Gequn Shu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期269-290,共22页
The supercritical CO_(2)(sCO_(2))power cycle could improve efficiencies for a wide range of thermal power plants.The sCO_(2)turbine generator plays an important role in the sCO_(2)power cycle by directly converting th... The supercritical CO_(2)(sCO_(2))power cycle could improve efficiencies for a wide range of thermal power plants.The sCO_(2)turbine generator plays an important role in the sCO_(2)power cycle by directly converting thermal energy into mechanical work and electric power.The operation of the generator encounters challenges,including high temperature,high pressure,high rotational speed,and other engineering problems,such as leakage.Experimental studies of sCO_(2)turbines are insufficient because of the significant difficulties in turbine manufacturing and system construction.Unlike most experimental investigations that primarily focus on 100 kW‐or MW‐scale power generation systems,we consider,for the first time,a small‐scale power generator using sCO_(2).A partial admission axial turbine was designed and manufactured with a rated rotational speed of 40,000 rpm,and a CO_(2)transcritical power cycle test loop was constructed to validate the performance of our manufactured generator.A resistant gas was proposed in the constructed turbine expander to solve the leakage issue.Both dynamic and steady performances were investigated.The results indicated that a peak electric power of 11.55 kW was achieved at 29,369 rpm.The maximum total efficiency of the turbo‐generator was 58.98%,which was affected by both the turbine rotational speed and pressure ratio,according to the proposed performance map. 展开更多
关键词 GENERATOR performance map power generation supercritical CO_(2) TURBINE
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审计质量、内部控制与企业高质量发展
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作者 王璇 姚维玲 《财务与金融》 2024年第4期82-89,共8页
高质量发展政策的提出对于企业从量到质的发展具有重大意义,内部控制和外部审计作为沟通企业和社会的桥梁,对企业高质量发展具有重要影响。选取2015年-2022年A股上市企业数据为研究样本,实证检验审计质量对企业高质量发展的影响。研究... 高质量发展政策的提出对于企业从量到质的发展具有重大意义,内部控制和外部审计作为沟通企业和社会的桥梁,对企业高质量发展具有重要影响。选取2015年-2022年A股上市企业数据为研究样本,实证检验审计质量对企业高质量发展的影响。研究结果表明,审计质量对企业高质量发展具有显著促进作用,经过稳健性检验和滞后性检验该结论依旧成立;调节效应发现,内部控制与审计质量能促进企业高质量发展;异质性分析发现,东部地区相较于中西部地区,审计质量更能显著促进企业的高质量发展。为促进企业高质量发展,政府应加强审计行业监管、完善审计规范标准;企业应健全内部控制制度、积极配合审计工作;审计机构应提升专业水平、强化自身独立性。 展开更多
关键词 审计质量 内部控制 企业高质量发展 全要素生产率
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Memristors-coupled neuron models with multiple firing patterns and homogeneous and heterogeneous multistability
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作者 xuan wang Santo Banerjee +1 位作者 Yinghong Cao Jun Mou 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期176-189,共14页
Memristors are extensively used to estimate the external electromagnetic stimulation and synapses for neurons.In this paper,two distinct scenarios,i.e.,an ideal memristor serves as external electromagnetic stimulation... Memristors are extensively used to estimate the external electromagnetic stimulation and synapses for neurons.In this paper,two distinct scenarios,i.e.,an ideal memristor serves as external electromagnetic stimulation and a locally active memristor serves as a synapse,are formulated to investigate the impact of a memristor on a two-dimensional Hindmarsh-Rose neuron model.Numerical simulations show that the neuronal models in different scenarios have multiple burst firing patterns.The introduction of the memristor makes the neuronal model exhibit complex dynamical behaviors.Finally,the simulation circuit and DSP hardware implementation results validate the physical mechanism,as well as the reliability of the biological neuron model. 展开更多
关键词 MEMRISTOR MULTISTABILITY Hamilton energy firing pattern Neuron model hardware implementation
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“Half of the Node Records Are Forged?”: The Problemof Node Records Forgery in Ethereum Network
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作者 Yang Liu Zhiyuan Lin +2 位作者 Yuxi Zhang Lin Jiang xuan wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1713-1729,共17页
Ethereum, currently the most widely utilized smart contracts platform, anchors the security of myriad smartcontracts upon its own robustness. Its foundational peer-to-peer network facilitates a dependable node connect... Ethereum, currently the most widely utilized smart contracts platform, anchors the security of myriad smartcontracts upon its own robustness. Its foundational peer-to-peer network facilitates a dependable node connectionmechanism, whereas an efficient data-sharing protocol constitutes as the bedrock of Blockchain network security.In this paper, we propose NodeHunter, an Ethereum network detector implemented through the application ofsimulation technology, which is capable of aggregating all node records within the network and the interconnectednessbetween them. Utilizing this connection information, NodeHunter can procure more comprehensive insightsfor network status analysis compared to preceding detection methodologies. Throughout a three-month period ofunbroken surveillance of the Ethereum network, we obtained an excess of two million node records along with overone hundred million node acquaintances. Analysis of the gathered data revealed that an alarming 49% or more ofthese node records were maliciously forged. 展开更多
关键词 Blockchain ethereum peer-to-peer networks node discovery protocol malicious behavior
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Exploring the molecular mechanism of Epimedium brevicornu Maxim.in treating breast cancer via network pharmacology and in vitro experiments
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作者 xuan wang Bin Cui +1 位作者 Liuyan Xu Xiaohua Pei 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第2期207-221,共15页
Objective:To evaluate the therapeutic effects of Epimedium brevicornu Maxim.(EBM,Yin Yang Huo)on breast cancer using network pharmacology and in vitro validation.It also aimed to explore the novel targets and mechanis... Objective:To evaluate the therapeutic effects of Epimedium brevicornu Maxim.(EBM,Yin Yang Huo)on breast cancer using network pharmacology and in vitro validation.It also aimed to explore the novel targets and mechanisms of EBM in the treatment of breast cancer to facilitate the discovery of new drugs and their clinical application.Methods: Network pharmacology was used to identify and screen the components and targets of EBM for breast cancer treatment.Molecular docking was further screened the effective components and targets of EBM.Wound-healing assays and flow cytometry analysis were used to detect the ability of two compounds to intervene in the migration and apoptosis of MDA-MB-231 cells,and their mechanism of action was further explored using western blotting experiments.Results: EBM contained 19 active components.Among them wereβ-anhydroicaritin(Anhy)and isoliquiritigenin(Iso),which were selected for in vitro experiments.Treatment resulted in a dose-dependent suppression of MDA-MB-231 cell viability,with an IC_(50) of 23.73μmol/L for Iso and 21.28μmol/L for Anhy.In the wound healing assay,cells in Anhy and Iso groups exhibited considerable inhibition of migration at 48 h.In flow cytometry analysis,treatment with Iso(20μmol/L)for 96 h resulted in significantly higher levels of both early and late apoptosis in the Iso group than that in the control group(P=.004 and P=.014,respectively).Additionally,both Iso(20μmol/L)and Anhy(10 and 20μmol/L)induced cell necrosis at 96 h.Western blotting revealed that Anhy and Iso increased the expression of Bax and TBK1/NAK.Conclusion: These findings suggested that Anhy and Iso,the two components of EBM,inhibit MDA-MB-231 cell proliferation and migration of and induce their apoptosis,providing substantial support for future studies on breast cancer. 展开更多
关键词 Breast cancer Epimedium brevicornu Maxim Molecular docking β-Anhydroicaritin ISOLIQUIRITIGENIN Flow cytometry MDA-MB-231
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High-Power Raman Soliton Generation at 1.7 μm in All-Fiber Polarization-Maintaining Erbium-Doped Amplifier
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作者 徐子鹏 王萱 +2 位作者 姚传飞 杨林京 李平雪 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期35-39,共5页
An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdope... An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdoped oscillator and two-stage amplifiers with polarization maintaining commercial silica fibers and devices, which can provide robust and stable soliton generation. High-power soliton laser with the average power of 0.28 W,the repetition rate of 42.7 MHz, and pulse duration of 515 fs is generated directly from the main amplifier.Our experiment provides a feasible method for high-power all-fiber polarization maintaining femtosecond laser generation working at 1.7 μm. 展开更多
关键词 polarization fiber AMPLIFIER
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Loneliness,social isolation and incident chronic kidney disease among patients with diabetes
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作者 Rui Tang Jian Zhou +4 位作者 xuan wang Hao Ma Xiang Li Yoriko Heianza Lu Qi 《General Psychiatry》 CSCD 2024年第3期440-448,共9页
Background Individuals with diabetes have a significantly higher risk of developing chronic kidney disease(CKD)and higher levels of social isolation and loneliness compared with those without diabetes.Recently,the Ame... Background Individuals with diabetes have a significantly higher risk of developing chronic kidney disease(CKD)and higher levels of social isolation and loneliness compared with those without diabetes.Recently,the American Heart Association highlighted the importance of considering social determinants of health(SDOH)in conjunction with traditional risk factors in patients with diabetes.Aims To investigate the associations of loneliness and social isolation with incident CKD risk in patients with diabetes in the UK Biobank.Methods A total of 18972 patients with diabetes were included in this prospective study.Loneliness and Social Isolation Scales were created based on self-reported factors.An adjusted Cox proportional hazard model was used to investigate the associations of loneliness and social isolation with CKD risk among patients with diabetes.The relative importance in predicting CKD was also calculated alongside traditional risk factors.Results During a median follow-up of 10.8 years,1127 incident CKD cases were reported.A higher loneliness scale,but not social isolation,was significantly associated with a 25%higher risk of CKD,independent of traditional risk factors,among patients with diabetes.Among the individual loneliness factors,the sense of feeling lonely emerged as the primary contributing factor to the elevated risk of CKD.Compared with individuals not experiencing feelings of loneliness,those who felt lonely exhibited a 22%increased likelihood of developing CKD.In addition,feeling lonely demonstrated greater relative importance of predicting CKD compared with traditional risk factors such as body mass index,smoking,physical activity and diet.Conclusions This study indicates the significant relationship between loneliness and CKD risk among patients with diabetes,highlighting the need to address SDOH in preventing CKD in this population. 展开更多
关键词 PATIENTS DIABETES KIDNEY
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Study on the Photosynthetic Characteristics of Six Varieties(Strains)in Chinese Chestnut
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作者 Lizhi FU Yong YANG +6 位作者 Xiaoxiao KANG Meng wang Jing LIU xuan wang Dongsheng wang Liyang YU Hai’e ZHANG 《Agricultural Biotechnology》 2024年第1期9-14,57,共7页
[Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis effici... [Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis efficiency breeding and application in Chinese chestnut.[Methods]Six Chinese chestnut varieties of Castanea mollissima‘Yanbao’,C.mollissima‘Yanqiu’,C.mollissima‘Yanchang’,C.mollissima‘Yanjia’,C.mollissima‘Qianxi 37’,and C.mollissima‘Hybrid 22’were used as the materials.Using the portable photosynthesis system Li-6400,we measured the photosynthetic characteristics and diurnal variation of leaf samples of six different chestnut varieties or strains.We fitted the light response curves and photosynthetic parameters using the leaf floating model.Additionally,we determined the chlorophyll content in the leaves using a UV-visible spectrophotometer.[Results]Among the six chestnut varieties or strains,‘Yanqiu’exhibited a significantly higher photosynthetic light saturation point(P LSP)compared to other five varieties,and‘Hybrid 22’ranked second,indicating that these two varieties had the strongest adaptation to high light intensity.The photosynthetic light compensation point(P LCP)of‘Yanchang’was significantly higher than other five varieties,and"Qianxi 37"ranked second,indicating that these two varieties had the strongest adaptation to low light intensity.Additionally,they exhibited higher chlorophyll content and maintained good photosynthetic characteristics even in shaded environments with weak light stress.Varieties‘Yanbao’and‘Yanjia’showed higher P LSP and lower P LCP,indicating that these two varieties have a wider range of adaptation to light intensity.They were capable of efficiently utilizing light across a broader spectrum of intensities.‘Yanqiu’had the highest maximum net photosynthetic rate(P n,max)and the lowest dark respiration rate(R d),along with the highest chlorophyll content.It indicated that‘Yanqiu’has strong photosynthetic capacity and organic matter accumulation ability.It also had the highest P LSP,enabling it to fully utilize the high light environment of the Yanshan Mountains and possessed high light efficiency characteristics.The P n,max of‘Yanqiu’was significantly higher than other varieties.‘Hybrid 22’and‘Yanbao’also exhibited significantly higher P n,max compared with‘Yanjia’and‘Qianxi 37’.‘Yanchang’had the lowest P n,max.The order of P n,max among the six chestnut varieties or strains was as follows:‘Yanqiu’>‘Hybrid 22’>‘Yanbao’>‘Yanjia’>‘Qianxi 37’>‘Yanchang’.[Conclusions] 展开更多
关键词 Chinese chestnut Diurnal variation of photosynthesis Light response model Light response curve CHLOROPHYLL
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中药植物紫草天然产物的生物合成及其功能研究进展 被引量:15
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作者 林红燕 王煊 +7 位作者 何聪 周紫玲 杨旻恺 文钟灵 韩洪苇 陆桂华 戚金亮 杨永华 《遗传》 CAS CSCD 北大核心 2021年第5期459-472,共14页
紫草为我国传统的重要药用植物资源,其根部代谢产生的紫红色萘醌类天然产物—紫草素及其衍生物,临床上常被用于治疗疮疡和皮肤炎症。数十年来,紫草因具高效的多重生物活性、药理作用、良好的临床疗效、较高的利用价值,引起了国内外研究... 紫草为我国传统的重要药用植物资源,其根部代谢产生的紫红色萘醌类天然产物—紫草素及其衍生物,临床上常被用于治疗疮疡和皮肤炎症。数十年来,紫草因具高效的多重生物活性、药理作用、良好的临床疗效、较高的利用价值,引起了国内外研究者的重视与关注,正由于此种原因,其野生植物种质资源常遭到大量采挖,生长环境受到严重威胁。随着植物天然产物的生物合成、分子代谢及其生物技术的发展,药用植物天然产物生物活性功能与药理作用研究手段的不断创新,紫草的生物合成途径和相关调控基因的研究取得了显著的进展,紫草素药理作用及其机制得到深入阐明或解析,极大地推进了紫草素的基础性研究及其临床应用开发的进程。本文从紫草分类、紫草素的结构与组成及其生物合成途径、调控紫草素生物合成代谢的功能相关基因以及紫草素生物活性与药理功能等方面综述了相关研究进展,并对未来可能的发展趋势进行了展望,以期为促进我国重要中药材源的药用天然产物的深度挖掘与开发提供有益参考,推动我国传统中药学的现代化发展。 展开更多
关键词 紫草 紫草素 生物合成 基因调控 药理活性
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食管癌术后淋巴结状态对术后辅助治疗选择的预测价值 被引量:6
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作者 宋春洋 祝淑钗 +6 位作者 王旋 高丝娜 赵彦 许金蕊 李曙光 闫可 张雪原 《中国肿瘤临床》 CAS CSCD 北大核心 2020年第2期66-71,共6页
目的:分析食管癌患者术后的淋巴结状态对术后辅助治疗方案选择的预测价值及与预后的关系。方法:分析2007年1月至2010年12月河北医科大学第四医院354例食管癌根治术后患者,对其淋巴结各相关参数与术后辅助治疗进行预后分析。单因素生存... 目的:分析食管癌患者术后的淋巴结状态对术后辅助治疗方案选择的预测价值及与预后的关系。方法:分析2007年1月至2010年12月河北医科大学第四医院354例食管癌根治术后患者,对其淋巴结各相关参数与术后辅助治疗进行预后分析。单因素生存分析采用Kaplan-Meier法和Log-rank检验,多因素生存分析采用Cox回归模型。结果:全组患者1、3、5年生存率分别为84.46%、64.12%和54.06%,中位生存期为86.49个月。N0、N1、N2、N3期患者的5年生存率分别为93.13%、55.50%、19.80%和3.45%,不同N分期之间的差异具有统计学意义(χ^2=225.161,P<0.001)。通过ROC曲线获取阳性淋巴结数目与清扫总淋巴结数目的比值(LNR)为分组界值8.51%将其分为两组并进行生存分析,LNR≤8.51%组及LNR>8.51%组患者的5年生存率分别为81.63%和23.40%,两组之间的差异具有统计学意义(χ^2=143.504,P<0.001)。单因素预后分析显示术后T分期、N分期、LNR、阴性淋巴结数目与患者的生存预后均相关(均P<0.05)。多因素预后分析显示术后N分期、LNR为生存预后的独立影响因素(均P<0.05)。N2组及LNR>8.51%组接受术后辅助治疗的患者生存显著优于单纯手术组(χ^2=12.609,P<0.001;χ^2=13.171,P<0.001)。联合N分期及LNR进行分析,在LNR>8.51%组的N2期患者接受术后辅助治疗组生存显著优于单纯手术组(χ^2=12.609,P<0.001)。结论:LNR可以协同N分期更好地提示预后并指导食管癌根治术后患者辅助治疗的选择。对N2期同时伴有高LNR的患者应该积极选择术后辅助治疗。 展开更多
关键词 食管恶性肿瘤 手术 淋巴结状态 术后辅助治疗 预后
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碳纤维改性聚四氟乙烯的摩擦及振动性能 被引量:7
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作者 杨雪 李少楠 +1 位作者 王轩 胡晓阳 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第5期60-65,73,共7页
文中研究了20%的碳纤维(体积分数)改性聚四氟乙烯在干摩擦和水润滑摩擦条件下的摩擦系数、磨损性能和摩擦振动性能。结果表明:(1)在干摩擦下,随着线速度增加,摩擦界面生成大量的热,黏着磨损和磨粒磨损严重,表面越来越粗糙,摩擦系数明显... 文中研究了20%的碳纤维(体积分数)改性聚四氟乙烯在干摩擦和水润滑摩擦条件下的摩擦系数、磨损性能和摩擦振动性能。结果表明:(1)在干摩擦下,随着线速度增加,摩擦界面生成大量的热,黏着磨损和磨粒磨损严重,表面越来越粗糙,摩擦系数明显变大,摩擦振动加速度增加。而在水润滑条件下,随着线速度增加,摩擦界面间形成了一层水润滑膜,使摩擦系数降低,另外由于转速增加,使流噪声增加,从而使振动增加。(2)在干摩擦下,随着比压增加,摩擦系数和摩擦振动变化较大,而在水润滑条件下,随着比压增加,摩擦系数和摩擦振动变化较小。(3)干摩擦时,碳纤维增强聚四氟乙烯复合材料在不同比压下的磨损机理主要是磨粒磨损和黏着磨损;水润滑条件下,碳纤维增强聚四氟乙烯复合材料在高比压下的磨损机理主要是黏着磨损。因此,碳纤维改性聚四氟乙烯复合材料应该在水润滑条件下应用有利于提高耐磨性,降低摩擦系数和摩擦振动。 展开更多
关键词 碳纤维 聚四氟乙烯 摩擦系数 磨损 摩擦振动
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转移性乳头状肾细胞癌的临床特征及预后分析
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作者 唐碧霞 李彩莉 +11 位作者 鄢谢桥 李思明 迟志宏 斯璐 崔传亮 毛丽丽 连斌 王轩 周莉 白雪 郭军 盛锡楠 《中国肿瘤临床》 CAS CSCD 北大核心 2019年第17期883-886,共4页
目的:探讨转移性乳头状肾细胞癌(papillary renal cell carcinoma,pRCC)的临床特征、酪氨酸激酶抑制剂(tyrosine kinase inhibitor,TKI)及雷帕霉素靶蛋白(mechanistic target of rapamycin kinase,mTOR)抑制剂系统性靶向治疗疗效及预后... 目的:探讨转移性乳头状肾细胞癌(papillary renal cell carcinoma,pRCC)的临床特征、酪氨酸激酶抑制剂(tyrosine kinase inhibitor,TKI)及雷帕霉素靶蛋白(mechanistic target of rapamycin kinase,mTOR)抑制剂系统性靶向治疗疗效及预后情况。方法:回顾性分析2003年1月至2018年3月93例北京大学肿瘤医院收治的转移性pRCC患者的临床资料,采用国际转移性肾细胞癌联合数据库(internationalmetastatic renal cell carcinoma database consortium,IMDC)预后模型对患者进行预后危险分层。采用Kaplan-Meier法及Cox比例风险回归模型对生存及影响因素进行分析。结果:93例转移性pRCC患者中Ⅱ型占95.7%(89/93),Ⅰ型占4.3%(4/93),伴肉瘤分化占11.8%(11/93),中位年龄为50.0 (22~87)岁,中位随访时间为23.1个月,中位总生存(overall survival,OS)时间为(31.5±5.9)个月(95% CI为19.9~43.1)。采用IMDC预后模型进行分层,低、中、高危患者分别占14.0%(13/93)、46.2%(43/93)、39.8%(37/93),低、中、高危患者的中位OS分别为(100.0±32.8)、(38.3±8.2)、(16.4±1.2)个月,高危与低、中危患者的OS相比差异具有统计学意义(P<0.001),低危与中危患者的OS相比差异无统计学意义(P=0.015)。93例pRCC患者的一线靶向治疗的总中位无疾病进展(progression free survival,PFS)时间为(6.6±0.5)个月,低、中、高危患者一线靶向治疗的PFS分别为(17.5±5.7)、(7.1±2.3)、(5.2±1.5)个月,高危与低危患者、高危与中危患者的PFS相比差异具有统计学意义(P=0.002、P=0.01)。结论:转移性pRCC具有独特的生物学特点,IMDC预后模型可用于预测转移性pRCC患者的TKI一线靶向治疗的疗效和预后生存。 展开更多
关键词 转移性 乳头型肾细胞癌 靶向治疗
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聚四氢呋喃醚二醇相对分子质量对聚氨酯耐辐照性能的影响
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作者 杨雪 王轩 聂敏 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第12期52-57,共6页
文中针对聚氨酯(PU)软段耐辐照性能差制约其在高能辐照领域的应用,采用不同相对分子质量的聚四氢呋喃醚二醇合成了一系列PU材料,研究了其辐照前后的结构和性能。结果表明,当多元醇相对分子质量为650时,软段排列紧密,可有效抵抗电子辐照... 文中针对聚氨酯(PU)软段耐辐照性能差制约其在高能辐照领域的应用,采用不同相对分子质量的聚四氢呋喃醚二醇合成了一系列PU材料,研究了其辐照前后的结构和性能。结果表明,当多元醇相对分子质量为650时,软段排列紧密,可有效抵抗电子辐照对材料的损伤,因而辐照后PU的力学性能保持完好。随着多元醇相对分子质量增加至1000,软段尺寸变大,辐照后PU易发生氧化降解,PU的力学性能显著下降。当多元醇的相对分子质量进一步增加,软段内分子链超过其临界缠结长度,分子链相互缠结,可在一定程度上抑制软段对辐射的阻抗作用,辐照后样品的力学性能可保持原始样品的70%。 展开更多
关键词 聚氨酯 高能辐照 氧化降解 力学性能
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老年营养风险指数对根治性放化疗食管鳞癌患者长期生存的预测价值 被引量:9
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作者 吴佩纹 祝淑钗 +3 位作者 宋春洋 赵彦 王旋 邓文钊 《中国肿瘤临床》 CAS CSCD 北大核心 2021年第14期721-727,共7页
目的:探讨老年营养风险指数(geriatric nutritional risk index,GNRI)对接受根治性放化疗(definitive chemoradiotherapy,dCRT)的食管鳞状细胞癌(esophageal squamous cell carcinoma,ESCC)患者长期生存的预测价值。方法:共收集2013年1... 目的:探讨老年营养风险指数(geriatric nutritional risk index,GNRI)对接受根治性放化疗(definitive chemoradiotherapy,dCRT)的食管鳞状细胞癌(esophageal squamous cell carcinoma,ESCC)患者长期生存的预测价值。方法:共收集2013年1月至2015年12月期间202例在河北医科大学第四医院接受根治性放化疗ESCC患者的临床资料。计算放疗前1周内患者GNRI和预后营养指数(prognostic nutritional index,PNI),将患者分为高GNRI组(GNRI≥98)和低GNRI组(GNRI<98)。回顾性分析GNRI对无进展生存(progression-free survival,PFS)和总生存(overall survival,OS)的影响。利用R软件建立列线图预测模型,以一致性指数(C-index)和校准曲线评估模型准确度,进一步探索GNRI和N分期、GNRI和PNI联合指标的预后预测价值。结果:202例患者中,高GNRI组145例(71.8%),低GNRI组57例(28.2%)。多因素分析显示,N分期、放疗剂量和GNRI是PFS和OS的独立预后因素。根据预后因素分别建立PFS和OS的列线图模型,C-index分别是0.663,0.656,1,3,5年PFS和OS的校准图显示出预测值与实际值具有较好的一致性。将GNRI和N分期联合、GNRI和PNI联合分析时,发现两项指标较单纯GNRI相比,其预测预后生存的精确度显著增加(GNRI、coGNRI-N、coGNRI-PNI的AUROCs=0.628、0.657、0.694)。结论:GNRI可作为根治性放化疗食管鳞癌患者生存的一个简便高效的预测指标。GNRI联合N分期与GNRI联合PNI可提高预测准确性。 展开更多
关键词 食管鳞状细胞癌 老年营养风险指数 根治性放化疗 预后 列线图
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聚乙二醇-氧化亚铜微胶囊防污涂料的制备及性能 被引量:5
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作者 毛田野 陆刚 +2 位作者 余红伟 王轩 王源升 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第9期8-13,共6页
采用葡萄糖还原-单凝聚法合成了聚乙二醇-氧化亚铜(PEG-Cu2O)微胶囊,并用透射电镜和红外光谱对微胶囊的结构组成和包覆效果进行了验证。以合成的微胶囊为防污剂,聚氨酯/环氧树脂(PU/EP)共混树脂为基体制备防污涂料试样,并对涂料试样的... 采用葡萄糖还原-单凝聚法合成了聚乙二醇-氧化亚铜(PEG-Cu2O)微胶囊,并用透射电镜和红外光谱对微胶囊的结构组成和包覆效果进行了验证。以合成的微胶囊为防污剂,聚氨酯/环氧树脂(PU/EP)共混树脂为基体制备防污涂料试样,并对涂料试样的涂层硬度、抗冲击性、拉伸强度、剪切强度、吸水性能及释放性能等进行了测试。探究了防污剂的种类和用量对防污涂料性能的影响,结果发现与使用普通Cu2O作为防污剂的涂料试样相比,使用PEG-Cu2O微胶囊的涂料试样涂层硬度、抗冲击性、拉伸强度、剪切强度、吸水率和缓释效果等性能均有了较大幅度的提升和改善;但当PEG-Cu2O用量增加至40 phr时,微胶囊对防污涂料性能的改善效果有一定程度的减弱;综合考虑涂料试样的各种性能,确定PEG-Cu2O用量以20 phr为宜。对遴选的优异配方涂料进行浅海挂板防污试验,结果发现,用量为20 phr的微胶囊涂料达到了与商品防污涂料基本相当的防污效果。 展开更多
关键词 聚乙二醇 氧化亚铜 微胶囊 防污涂料 浅海挂板试验
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自修复抗穴蚀微胶囊的制备及性能表征 被引量:7
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作者 马凯文 王源升 +1 位作者 王轩 杨宏波 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第7期62-68,共7页
探究了W/O乳液自由基原位聚合制备以聚丙烯酰胺(PAM)水溶液为芯材、甲基丙烯酸酯树脂共聚物P(MMA-co-BMA)为壁材的自修复抗穴蚀微胶囊的方法。采用热重分析、红外光谱、扫描电镜等手段对自修复抗穴蚀微胶囊进行了性能分析和形貌表征。... 探究了W/O乳液自由基原位聚合制备以聚丙烯酰胺(PAM)水溶液为芯材、甲基丙烯酸酯树脂共聚物P(MMA-co-BMA)为壁材的自修复抗穴蚀微胶囊的方法。采用热重分析、红外光谱、扫描电镜等手段对自修复抗穴蚀微胶囊进行了性能分析和形貌表征。结果表明,此方法能合成P(MMA-co-BMA)包覆PAM水溶液微胶囊,其粒径约为40μm,包覆率达到70%以上。通过改变P(MMA-co-BMA)中甲基丙烯酸甲酯(MMA)、甲基丙烯酸丁酯(BMA)的共聚比例,制备出具有不同自修复抗穴蚀行为的微胶囊,将其添加到环氧树脂基体中固化,通过超声磁致振动装置定量表征了改性环氧树脂的失重性能。实验结果表明,PAM水溶液微胶囊具有自修复抗穴蚀性能,当BMA、MMA共聚比例为2.5∶7.5时,微胶囊抗穴蚀性能最佳。 展开更多
关键词 微胶囊 穴蚀 原位聚合法 聚丙烯酰胺 甲基丙烯酸酯树脂共聚物
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ARID1A基因突变或失表达介导肿瘤发生的机制及其在胃癌免疫治疗中的价值 被引量:3
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作者 王璇 刘宝瑞(综述) 魏嘉(审校) 《中国肿瘤临床》 CAS CSCD 北大核心 2020年第18期955-960,共6页
AT丰富结合域1A(AT-rich interactive domain 1A,ARID1A)是染色质重塑复合体SWI/SNF(SWItch/Sucrose non-ferment⁃able)的一个亚基,它是所有肿瘤中突变最频繁的染色质调节因子之一,这些突变大部分是移码或无义突变。ARID1A是一个抑癌基... AT丰富结合域1A(AT-rich interactive domain 1A,ARID1A)是染色质重塑复合体SWI/SNF(SWItch/Sucrose non-ferment⁃able)的一个亚基,它是所有肿瘤中突变最频繁的染色质调节因子之一,这些突变大部分是移码或无义突变。ARID1A是一个抑癌基因,它的突变或失表达可能从不同的途径导致肿瘤的发生发展。同时,ARID1A突变或表达缺失与胃癌程序性死亡受体-配体1(programmed cell death-ligand 1,PD-L1)高表达、EB病毒(Epstein-Barr virus,EBV)阳性、微卫星高度不稳定性(microsatellite insta⁃bility-high,MSI-H)、高肿瘤突变负荷(tumor mutation burden,TMB)及较多的肿瘤浸润淋巴细胞(tumor infiltrating lymphocytes,TILs)相关,且免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)可以明显延长ARID1A缺失的肿瘤患者的无进展生存期。本文就ARID1A基因突变或失表达导致肿瘤发生可能途径及其与胃癌免疫治疗的关系进行综述。 展开更多
关键词 ARID1A 肿瘤发生 胃癌 免疫治疗
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PR状态方程+基团贡献模型预测CO_(2)+HFC二元混合物的气液相平衡性质
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作者 吴子睿 石凌峰 +3 位作者 孙瑞 田华 王轩 舒歌群 《中国科学技术大学学报》 CAS CSCD 北大核心 2023年第10期52-59,I0008,共9页
由于良好的性能和环保性,CO_(2)+HFC二元混合物被认为是冷电联合循环系统中良好的替代工作流体。气液相平衡特性是计算混合物焓和熵的关键,这冷电联合循环系统的热力学分析至关重要。为了准确预测CO_(2)和HFC(R23,R32,R41,R125,R134a,R1... 由于良好的性能和环保性,CO_(2)+HFC二元混合物被认为是冷电联合循环系统中良好的替代工作流体。气液相平衡特性是计算混合物焓和熵的关键,这冷电联合循环系统的热力学分析至关重要。为了准确预测CO_(2)和HFC(R23,R32,R41,R125,R134a,R143a,R152a,R161,R227ea)二元混合物的气液平衡性质,本文建立了基于吉布斯自由能混合规则的群贡献模型(PR+MHV1+UNIFAC和PR+LCVM+UNIFAC)。通过CO_(2)和HFC制冷剂的气液相平衡实验获得了-CO_(2)、-烷烃、-CHF和-CHF3等基团之间的相互作用参数,这些基团参数对于预测其气液相平衡性质(压力和气相摩尔分数)至关重要。PR+LCVM+UNIFAC模型计算的AARDp值为5.53%,AADy1值为0.0132,PR+MHV1+UNIFAC模型的AARDp值和AADy1值分别为7.40%和0.0229。然而,对于CO_(2)+R32系统,PR+MHV+UNIFAC预测模型的预测精度较高,AARDp和AADy1的值分别为1.53%和0.0045。综上所述,对于CO_(2)+HFC二元混合物,PR+LCVM+UNIFAC预测模型预测精度较高,但对于CO_(2)+R32二元混合物,PR+MHV1+UNIFAC模型也具有独特的优势。根据基团贡献模型的预测结果,与之前系统使用的PR+MHV1+UNIFAC模型相比,PR+LCVM+UNIFAC模型的计算进度显著提高。 展开更多
关键词 冷电联合循环 CO_(2)+HFC二元混合物 气液相平衡 基团贡献模型 PR+MHV1+UNIFAC模型 PR+LCVM+UNIFAC模型
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