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Voluntary wheel running ameliorated the deleterious effects of high-fat diet on glucose metabolism,gut microbiota and microbial-associated metabolites
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作者 Ling Zhang Wenyu Zou +4 位作者 Yongyan Hu Honghua Wu Ying Gao Junqing Zhang Jia Zheng 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1672-1684,共13页
Exercise training is critical for the early prevention and treatment of obesity and diabetes mellitus.However,the mechanism with gut microbiota and fecal metabolites underlying the effects of voluntary wheel running o... Exercise training is critical for the early prevention and treatment of obesity and diabetes mellitus.However,the mechanism with gut microbiota and fecal metabolites underlying the effects of voluntary wheel running on high-fat diet induced abnormal glucose metabolism has not been fully elaborated.C57BL/6 male mice were randomly assigned to 4 groups according to diets(fed with normal chow diet or high-fat diet)and running paradigm(housed in static cage or with voluntary running wheel).An integrative 16S rDNA sequencing and metabolites profiling was synchronously performed to characterize the effects of voluntary wheel running on gut microbiota and metabolites.It showed that voluntary wheel running prevented the detrimental effects of high-fat feeding on glucose metabolism 16S rDNA sequencing showed remarkable changes in Rikenella and Marvinbryantia genera.Metabolic profiling indicated multiple altered metabolites,which were enriched in secondary bile acid biosynthesis signaling.In conclusion,our study indicated that voluntary wheel running significantly improved glucose metabolism and counteracted the deleterious effects of high-fat feeding on body weight and glucose intolerance.We further found that voluntary wheel running could integratively program gut microbiota composition and fecal metabolites changes,and may regulate muricholic acid metabolism and secondary bile acid biosynthesis in high-fat fed mice. 展开更多
关键词 High-fat diet Voluntary wheel running Gut microbiota Metabolomics Glucose metabolism
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Influence of pier height on the safety of trains running on high-speed railway bridges during earthquakes
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作者 NIE Yu-tao GUO Wei +8 位作者 JIANG Li-zhong YU Zhi-wu ZENG Chen WANG Yang HE Xu-en REN Shao-xun HUANG Ren-qiang LIANG Guang-yue LI Chang-qing 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2102-2115,共14页
Sudden earthquakes pose a threat to the running safety of trains on high-speed railway bridges,and the stiffness of piers is one of the factors affecting the dynamic response of train-track-bridge system.In this paper... Sudden earthquakes pose a threat to the running safety of trains on high-speed railway bridges,and the stiffness of piers is one of the factors affecting the dynamic response of train-track-bridge system.In this paper,a experiment of a train running on a high-speed railway bridge is performed based on a dynamic experiment system,and the corresponding numerical model is established.The reliability of the numerical model is verified by experiments.Then,the experiment and numerical data are analyzed to reveal the pier height effects on the running safety of trains on bridges.The results show that when the pier height changes,the frequency of the bridge below the 30 m pier height changes greater;the increase of pier height causes the transverse fundamental frequency of the bridge close to that of the train,and the shaking angle and lateral displacement of the train are the largest for bridge with 50 m pier,which increases the risk of derailment;with the pier height increases from 8 m to 50 m,the derailment coefficient obtained by numerical simulations increases by 75% on average,and the spectral intensity obtained by experiments increases by 120% on average,two indicators exhibit logarithmic variation. 展开更多
关键词 pier height high-speed railway bridge running safety numerical model
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A novel refined dynamic model of high-speed maglev train-bridge coupled system for random vibration and running safety assessment
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作者 MAO Jian-feng LI Dao-hang +3 位作者 YU Zhi-wu CAI Wen-feng GUO Wei ZHANG Guang-wen 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2532-2544,共13页
Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can b... Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can be well characterized based on various stochastic excitations.A three-dimensional refined spatial random vibration analysis model of high-speed maglev train-bridge coupled system is established in this paper,in which multi-source uncertainty excitation can be considered simultaneously,and the probability density evolution method(PDEM)is adopted to reveal the system-specific uncertainty dynamic characteristic.The motion equation of the maglev vehicle model is composed of multi-rigid bodies with a total 210-degrees of freedom for each vehicle,and a refined electromagnetic force-air gap model is used to account for the interaction and coupling effect between the moving train and track beam bridges,which are directly established by using finite element method.The model is proven to be applicable by comparing with Monte Carlo simulation.By applying the proposed stochastic framework to the high maglev line,the random dynamic responses of maglev vehicles running on the bridges are studied for running safety and stability assessment.Moreover,the effects of track irregularity wavelength range under different amplitude and running speeds on the coupled system are investigated.The results show that the augmentation of train speed will move backward the sensitive wavelength interval,and track irregularity amplitude influences the response remarkably in the sensitive interval. 展开更多
关键词 maglev train-bridge interaction electromagnetic force-air gap model stochastic dynamic analysis running safety assessment probability density evolution method
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Safety of the express freight train running over a long-span bridge
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作者 Jingcheng Wen Yihao Qin +1 位作者 Ye Bai Xiaoqing Dong 《Railway Sciences》 2024年第4期469-479,共11页
Purpose-Express freight transportation is in rapid development currently.Owing to the higher speed of express freight train,the deformation of the bridge deck worsens the railway line condition under the action of win... Purpose-Express freight transportation is in rapid development currently.Owing to the higher speed of express freight train,the deformation of the bridge deck worsens the railway line condition under the action of wind and train moving load when the train runs over a long-span bridge.Besides,the blunt car body of vehicle has poor aerodynamic characteristics,bringing a greater challenge on the running stability in the crosswind.Design/methodology/approach-In this study,the aerodynamic force coefficients of express freight vehicles on the bridge are measured by scale model wind tunnel test.The dynamic model of the train-long-span steel truss bridge coupling system is established,and the dynamic response as well as the running safety of vehicle are evaluated.Findings-The results show that wind speed has a significant influence on running safety,which is mainly reflected in the over-limitation of wheel unloading rate.The wind speed limit decreases with train speed,and it reduces to 18.83 m/s when the train speed is 160 km/h.Originality/value-This study deepens the theoretical understanding of the interaction between vehicles and bridges and proposes new methods for analyzing similar engineering problems.It also provides a new theoretical basis for the safety assessment of express freight trains. 展开更多
关键词 Express freight train Long-span bridge CROSSWIND Wind tunnel test running safety Paper type Research paper
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基于RUN-XGBoost算法的土石坝渗流预测模型 被引量:1
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作者 马春辉 侯媛媛 +2 位作者 杨杰 袁帅 徐笑颜 《水利水电科技进展》 CSCD 北大核心 2024年第2期72-78,共7页
针对传统土石坝渗流预测模型存在局部最优、抗干扰性差和预测精度低等问题,通过RUN算法优化XGBoost算法得到RUN-XGBoost算法,构建了RUN-XGBoost模型以获得更优的土石坝渗流预测结果。该模型在种群初始化时采用RUN算法对XGBoost算法的3... 针对传统土石坝渗流预测模型存在局部最优、抗干扰性差和预测精度低等问题,通过RUN算法优化XGBoost算法得到RUN-XGBoost算法,构建了RUN-XGBoost模型以获得更优的土石坝渗流预测结果。该模型在种群初始化时采用RUN算法对XGBoost算法的3个主要参数进行改进,使预测结果有较高的有效性;通过自动寻找最优参数增进算法的整体收敛速度和预测精度,同时引入随机解,使算法能够排除局部最小值并继续搜索,从而获得全局最优结果。工程实例验证结果表明,RUN-XGBoost模型具有简洁、高效、预测精度高、鲁棒性强等优点。 展开更多
关键词 土石坝 渗流监测 run-XGBoost算法 预测模型
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Acute effect of foot strike patterns on in vivo tibiotalar and subtalar joint kinematics during barefoot running
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作者 Dongqiang Ye Lu Li +4 位作者 Shen Zhang Songlin Xiao Xiaole Sun Shaobai Wang Weijie Fu 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期108-117,共10页
Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patte... Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patterns influence these specific foot and ankle kinematics.However,technical deficiencies in traditional motion capture approaches limit knowledge of in vivo joint kinematics with respect to rearfoot and forefoot strike patterns(RFS and FFS,respectively).This study uses a high-speed dual fluoroscopic imaging system(DFIS)to determine the effects of different foot strike patterns on 3D in vivo tibiotalar and subtalar joints kinematics.Methods:Fifteen healthy male recreational runners underwent foot computed tomography scanning for the construction of 3-dimensional models.A high-speed DFIS(100 Hz)was used to collect 6 degrees of freedom kinematics for participants’tibiotalar and subtalar joints when they adopted RFS and FFS in barefoot condition.Results:Compared with RFS,FFS exhibited greater internal rotation at 0%-20%of the stance phase in the tibiotalar joint.The peak internal rotation angle of the tibiotalar joint under FFS was greater than under RFS(p<0.001,Cohen’s d=0.92).RFS showed more dorsiflexion at 0%-20%of the stance phase in the tibiotalar joint than FFS.RFS also presented a larger anterior translation(p<0.001,Cohen’s d=1.28)in the subtalar joint at i nitial contact than FFS.Conclusion:Running with acute barefoot FFS increases the internal rotation of the tibiotalar joint in the early stance.The use of high-speed DFIS to quantify the movement of the tibiotalar and subtalar joint was critical to revealing the effects of RF S and FFS during running. 展开更多
关键词 Foot strike patterns High-speed dual fluoroscopic imaging system In vivo kinematics running
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Enhancement of motor functional recovery in thoracic spinal cord injury: voluntary wheel running versus forced treadmill exercise
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作者 Do-Hun Lee Dan Cao +4 位作者 Younghye Moon Chen Chen Nai-Kui Liu Xiao-Ming Xu Wei Wu 《Neural Regeneration Research》 SCIE CAS 2025年第3期836-844,共9页
Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery ... Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury. 展开更多
关键词 behavioral assessment motor function neural plasticity running wheel exercise spinal cord injury treadmill exercise voluntary exercise
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SmartMicro Grid Energy System Management Based on Optimum Running Cost for Rural Communities in Rwanda
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作者 Fabien Mukundufite Jean Marie Vianney Bikorimana Alexander Kyaruzi Lugatona 《Energy Engineering》 EI 2024年第7期1805-1821,共17页
The governmental electric utility and the private sector are joining hands to meet the target of electrifying all households by 2024.However,the aforementioned goal is challenged by households that are scattered in re... The governmental electric utility and the private sector are joining hands to meet the target of electrifying all households by 2024.However,the aforementioned goal is challenged by households that are scattered in remote areas.So far,Solar Home Systems(SHS)have mostly been applied to increase electricity access in rural areas.SHSs have continuous constraints to meet electricity demands and cannot run income-generating activities.The current research presents the feasibility study of electrifying Remera village with the smart microgrid as a case study.The renewable energy resources available in Remera are the key sources of electricity in that village.The generation capacity is estimated based on the load profile.The microgrid configurations are simulated with HOMER,and the genetic algorithm is used to analyze the optimum cost.By analyzing the impact of operation and maintenance costs,the results show that the absence of subsidies increases the levelized cost of electricity(COE)five times greater than the electricity price from the public utility.The microgrid made up of PV,diesel generator,and batteries proved to be the most viable solution and ensured continuous power supply to customers.By considering the subsidies,COE reaches 0.186$/kWh,a competitive price with electricity from public utilities in Rwanda. 展开更多
关键词 Load demand load profile optimum running cost power demand satisfaction smart meters and smart micro grid
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Review of Research on English Translation of Chinese Running Sentences
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作者 ZHANG Wen-hui 《Journal of Literature and Art Studies》 2024年第7期624-627,共4页
In order to convey complete meanings,there is a phenomenon in Chinese of using multiple running sentences.Xu Jingning(2023,p.66)states,“In communication,a complete expression of meaning often requires more than one c... In order to convey complete meanings,there is a phenomenon in Chinese of using multiple running sentences.Xu Jingning(2023,p.66)states,“In communication,a complete expression of meaning often requires more than one clause,which is common in human languages.”Domestic research on running sentences includes discussions on defining the concept and structural features of running sentences,sentence properties,sentence pattern classifications and their criteria,as well as issues related to translating running sentences into English.This article primarily focuses on scholarly research into the English translation of running sentences in China,highlighting recent achievements and identifying existing issues in the study of running sentence translation.However,by reviewing literature on the translation of running sentences,it is found that current research in the academic community on non-core running sentences is limited.Therefore,this paper proposes relevant strategies to address this issue. 展开更多
关键词 Chinese running sentences TOPICS English-Chinese translation
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基于辛Runge-Kutta方法的棋盘形褶皱二维薄膜-基底结构动力学特性研究
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作者 张博涵 曹善成 +2 位作者 王博 欧阳华江 徐方暖 《计算力学学报》 CAS CSCD 北大核心 2024年第1期186-193,共8页
基于力学屈曲原理的褶皱薄膜-基底结构已成功应用于制备可延展无机电子器件。然而,该类电子器件在应用时需要服役于复杂动态环境中,针对棋盘形褶皱薄膜结构的动力学问题鲜有研究,此问题又是该类电子器件走向实际应用需要解决的关键问题... 基于力学屈曲原理的褶皱薄膜-基底结构已成功应用于制备可延展无机电子器件。然而,该类电子器件在应用时需要服役于复杂动态环境中,针对棋盘形褶皱薄膜结构的动力学问题鲜有研究,此问题又是该类电子器件走向实际应用需要解决的关键问题之一。本文首先采用能量方法,分别计算了二维薄膜的弯曲能、膜弹性能和柔性基底中的弹性能以及薄膜动能;然后采用拉格朗日方程,推导出了该结构的振动控制方程;而该方程为非线性动力学方程,无法给出其解析解;因此,本文采用辛Runge-Kutta方法对其进行数值求解;数值结果表明,辛数值方法具有长期稳定的特性和系统结构特性,为高精度的可延展电子器件的动力学问题研究提供了优异的数值方法。 展开更多
关键词 可延展电子器件 薄膜-基底结构 辛算法 保结构
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汽车零部件Milk-run业务公铁联运模式下的铁路货运站选址研究
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作者 宋玉阳 《铁道货运》 2024年第2期28-33,共6页
能否精准科学地选择汽车零部件循环取货(Milk-run)业务中公铁联运模式的铁路货运站,将直接影响物流总成本。随着公铁联运模式在节能减排与降本增效中的优势逐渐呈现,汽车生产商也开始在零部件物流领域探索Milk-run业务采用公铁联运方式... 能否精准科学地选择汽车零部件循环取货(Milk-run)业务中公铁联运模式的铁路货运站,将直接影响物流总成本。随着公铁联运模式在节能减排与降本增效中的优势逐渐呈现,汽车生产商也开始在零部件物流领域探索Milk-run业务采用公铁联运方式。基于以往研究基础,对汽车零部件Milk-run业务中采用公铁联运的背景进行分析,以重庆长安福特汽车有限公司华东片区的Milk-run业务为例,构建基于公铁联运的Milk-run物流运作模式,发现在运作过程中需要确定Milk-run业务中的铁路货运站地址。为精确、合理地进行选址,采用定量与定性相结合的方法,运用精确重心法计算出铁路货运站备选地址范围,再利用综合指标评级法在备选地址中确定地址,最终通过优化选址,提高企业Milk-run业务中物流的运作效率。 展开更多
关键词 公铁联运 MILK-run 铁路货运站 选址 重心法
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LncRNA TMPO-AS1调节miR-340-5p/RUNX1轴对结直肠癌细胞增殖、迁移和侵袭的影响
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作者 许汉兵 韩建涛 张成鹏 《河北医药》 CAS 2024年第2期165-170,共6页
目的探讨长链非编码RNA TMPO反义RNA1(LncRNA TMPO-AS1)调控miR-340-5p/RUNT相关转录因子1(RUNX1)轴对结直肠癌(CRC)细胞增殖、迁移和侵袭的影响。方法qRT-PCR检测人正常结肠上皮细胞HCoEpiC、人CRC细胞SW480、HCT116、LOVO、HT-29中TMP... 目的探讨长链非编码RNA TMPO反义RNA1(LncRNA TMPO-AS1)调控miR-340-5p/RUNT相关转录因子1(RUNX1)轴对结直肠癌(CRC)细胞增殖、迁移和侵袭的影响。方法qRT-PCR检测人正常结肠上皮细胞HCoEpiC、人CRC细胞SW480、HCT116、LOVO、HT-29中TMPO-AS1、miR-340-5p、RUNX1表达;将HCT116细胞随机分为:si-ctrl组、si-TMPO-AS1组、mimics NC组、miR-340-5p组、si-TMPO-AS1+anti-miR-ctrl组、si-TMPO-AS1+anti-miR-340-5p组;qRT-PCR检测6组HCT116细胞TMPO-AS1、miR-340-5p、RUNX1水平;CCK-8法检测HCT116细胞活力;EDU法检测HCT116细胞增殖;Transwell检测HCT116细胞迁移和侵袭;western blot检测HCT116细胞RUNX1、PCNA、MMP-2表达;双荧光素酶报告基因实验分别验证TMPO-AS1和miR-340-5p、miR-340-5p和RUNX1的关系。结果与HCoEpiC细胞比较,不同CRC细胞中TMPO-AS1、RUNX1表达显著性升高,miR-424-5p表达显著性降低(P<0.05),且HCT116细胞变化结果更显著,后续实验选择HCT116细胞。与si-ctrl组比较,si-TMPO-AS1组HCT116细胞TMPO-AS1、RUNX1 mRNA水平、细胞活力A值、EDU阳性细胞率、迁移与侵袭细胞数、RUNX1、PCNA、MMP-2蛋白水平均显著性降低,miR-340-5p mRNA水平显著性升高(P<0.05);与mimics NC组比较,miR-340-5p组HCT116细胞RUNX1 mRNA水平、细胞活力A值、EDU阳性细胞率、迁移与侵袭细胞数、RUNX1、PCNA、MMP-2蛋白水平均显著性降低,miR-340-5p mRNA水平显著性升高(P<0.05);与si-TMPO-AS1+anti-miR-ctrl组比较,si-TMPO-AS1+anti-miR-340-5p组HCT116细胞RUNX1 mRNA水平、细胞活力A值、EDU阳性细胞率、迁移与侵袭细胞数、RUNX1、PCNA、MMP-2蛋白水平均显著性升高,miR-340-5p mRNA水平显著性降低(P<0.05);TMPO-AS1靶向负调控miR-340-5p表达,miR-340-5p靶向负调控RUNX1表达。结论沉默TMPO-AS1靶向上调miR-340-5p表达,从而下调RUNX1表达,抑制HCT116细胞增殖、迁移和侵袭。 展开更多
关键词 LncRNA TMPO-AS1 miR-340-5p runX1 结直肠癌细胞
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血清标志物BAGE5、RUNX1T1、SLFN14对比CA19-9在胰腺癌诊断中的比较研究:一项全面评估其临床应用前景的综述
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作者 王宏基 谭云波 金礼权 《临床医学进展》 2024年第3期884-888,共5页
胰腺癌作为消化道最常见的恶性肿瘤之一,病因尚不明确,临床常表现为上腹不适、腹泻、食欲减退、腹痛、黄疸等。胰腺位于腹腔深部,疾病早期症状无特异性,起病较为隐匿,患者往往难以察觉且临床难以诊断。近年来,胰腺癌的发生率在国内外均... 胰腺癌作为消化道最常见的恶性肿瘤之一,病因尚不明确,临床常表现为上腹不适、腹泻、食欲减退、腹痛、黄疸等。胰腺位于腹腔深部,疾病早期症状无特异性,起病较为隐匿,患者往往难以察觉且临床难以诊断。近年来,胰腺癌的发生率在国内外均呈明显上升趋势。胰腺癌的常用诊断方法包括影像学检查、肿瘤标志物检查以及组织病理学检验,目前临床早期筛查胰腺癌的肿瘤标记物是CA19-9,它被认为在胰腺癌检测时敏感性和特异性不理想,CA19-9升高占比低,检测到CA19-9升高时胰腺癌已进展到晚期。有研究表明,肿瘤标记物和生化单独检测对胰腺癌早期诊断价值不高,若用2种及2种以上的肿瘤标记物联合检测可帮助胰腺癌的筛选以及鉴别,且早期诊断可有效提高胰腺癌患者生存率。BAGE5、RUNX1T1、SLFN14与胰腺癌存在潜在相关性,或可作为新的血清标志物诊断胰腺癌,本文将评估其临床应用前景。 展开更多
关键词 胰腺癌 CA19-9 BAGE5 runX1T1 SLFN14
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RUNX3 mRNA、IFN-γ、IgE水平检测在毛细支气管炎患儿中的临床意义
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作者 张沥文 刘琦 +2 位作者 田鹏 杜静 何刚 《检验医学与临床》 CAS 2024年第19期2811-2814,2819,共5页
目的分析runt相关转录因子3(RUNX3)mRNA、干扰素-γ(IFN-γ)、免疫球蛋白E(IgE)水平检测在毛细支气管炎患儿中的临床意义。方法选取2019年3月至2022年1月在该院诊治的104例毛细支气管炎患儿作为观察组(轻度28例、中度52例、重度24例),... 目的分析runt相关转录因子3(RUNX3)mRNA、干扰素-γ(IFN-γ)、免疫球蛋白E(IgE)水平检测在毛细支气管炎患儿中的临床意义。方法选取2019年3月至2022年1月在该院诊治的104例毛细支气管炎患儿作为观察组(轻度28例、中度52例、重度24例),另选取同期体检健康的57例婴幼儿作为对照组。采用荧光定量PCR检测RUNX3 mRNA水平,采用酶联免疫吸附试验(ELISA)检测血清中IFN-γ、IgE水平。比较两组RUNX3 mRNA、IFN-γ、IgE水平,绘制受试者工作特征(ROC)曲线评估RUNX3 mRNA、IFN-γ、IgE水平对小儿毛细支气管炎的诊断价值,比较不同病情程度患儿RUNX3 mRNA、IFN-γ、IgE水平,采用Spearman相关分析RUNX3 mRNA、IFN-γ、IgE水平与病情程度的相关性。结果与对照组相比,观察组RUNX3 mRNA、IFN-γ水平明显较低,IgE水平明显较高,差异均有统计学意义(P<0.001)。ROC曲线分析结果显示,RUNX3 mRNA、IFN-γ、IgE诊断小儿毛细支气管炎的曲线下面积(AUC)分别为0.731(95%CI:0.655~0.797)、0.850(95%CI:0.780~0.901)、0.867(95%CI:0.805~0.915)。不同程度毛细支气管炎患儿RUNX3 mRNA、IFN-γ水平表现为轻度组>中度组>重度组,IgE水平表现为轻度组<中度组<重度组,任意两组间比较,差异均有统计学意义(P<0.05)。Spearman相关分析结果显示,RUNX3 mRNA、IFN-γ水平与病情程度呈负相关(r=-0.618、-0.547,P<0.001),IgE水平与病情程度呈正相关(r=0.574,P<0.001)。结论RUNX3 mRNA、IFN-γ、IgE水平对小儿毛细支气管炎有较好的诊断价值,且与病情程度有相关性,对毛细支气管炎的早期诊断、病情进展有一定的评估作用。 展开更多
关键词 runT相关转录因子3 干扰素-Γ 免疫球蛋白E 毛细支气管炎 相关性
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骨质疏松性椎体压缩性骨折患者血清BMP-2,Runx2水平对术后骨折延迟愈合的预测价值
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作者 王金龙 冯大军 周全 《新疆医科大学学报》 CAS 2024年第6期836-842,共7页
目的探讨骨质疏松性椎体压缩性骨折(Osteoporotic vertebral compressibility fracture,OVCF)患者血清骨形态发生蛋白-2(Bone morphogenetic protein-2,BMP-2)、核心结合因子2(Runt-related transcription factor 2,Runx2)水平对术后骨... 目的探讨骨质疏松性椎体压缩性骨折(Osteoporotic vertebral compressibility fracture,OVCF)患者血清骨形态发生蛋白-2(Bone morphogenetic protein-2,BMP-2)、核心结合因子2(Runt-related transcription factor 2,Runx2)水平对术后骨折延迟愈合的预测价值。方法选取2020年1月-2023年4月徐州医科大学附属淮安医院骨科收治的260例OVCF患者为研究对象,均采用经皮椎体成形术(Percutaneous vertebroplasty,PVP)或椎体后凸成形术(Percutanous kyphoplasty,PKP)治疗,根据术后3个月骨折愈合情况分延迟愈合组、正常愈合组。分析OVCF患者术后骨折延迟愈合的影响因素及血清BMP-2,Runx2水平对术后骨折延迟愈合的预测价值。绘制决策曲线和临床影响曲线,评价血清BMP-2,Runx2水平对术后骨折延迟愈合的价值。结果260例患者术后无失访,22例出现骨折延迟愈合,发生率为8.46%(22/260)。延迟愈合组年龄、吸烟比率、合并糖尿病比率、合并甲状腺疾病比率、有椎体裂隙征比率大于正常愈合组,骨密度T值、术前和术后3个月血清BMP-2,Runx2水平小于正常愈合组,差异有统计学意义(P<0.05)。合并糖尿病、有椎体裂隙征是OVCF患者术后骨折延迟愈合的独立危险因素,骨密度T值、BMP-2,Runx2是OVCF患者术后骨折延迟愈合的独立保护因素(P<0.05)。BMP-2,Runx2联合预测OVCF患者术后骨折延迟愈合对应AUC值为0.856。阈值在0.10~0.63范围内,BMP-2,Runx2联合评估模型评估OVCF患者术后骨折延迟愈合的净受益率优于单独检测。在阈值概率为0.26时,被该模型划分入高风险的人数与真阳性人数基本达成一致。结论OVCF患者血清BMP-2,Runx2水平降低,二者联合检测对术后骨折延迟愈合具有较高的预测效能。 展开更多
关键词 骨质疏松性椎体压缩性骨折 骨形态发生蛋白-2 核心结合因子2 术后骨折延迟愈合
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基于多维Copula函数的澜沧江-湄公河流域气象干旱特征分析 被引量:3
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作者 李琼芳 方凯悦 +4 位作者 韩幸烨 邹振华 陈启慧 尹瑞琪 林雍权 《水资源保护》 EI CSCD 北大核心 2024年第1期52-59,共8页
为全面揭示变化环境下澜湄流域多维气象干旱特征,采用标准化降水蒸散指数SPEI表征流域气象干旱,基于游程理论分别提取澜沧江段和湄公河段上、中、下游流域1901—1960年和1961—2021年两个时段的干旱事件,利用Copula函数分别构建两个时... 为全面揭示变化环境下澜湄流域多维气象干旱特征,采用标准化降水蒸散指数SPEI表征流域气象干旱,基于游程理论分别提取澜沧江段和湄公河段上、中、下游流域1901—1960年和1961—2021年两个时段的干旱事件,利用Copula函数分别构建两个时段不同子流域二维和三维干旱特征变量联合分布,计算不同干旱特征变量组合条件下的干旱联合发生概率,对比分析不同子流域多维气象干旱特征的时空变化。结果表明:时间上,1961—2021年各子流域平均干旱程度均较1901—1960年更严峻,尤其是极端干旱事件(单变量累积频率为25%、50%)的多维干旱联合发生概率增幅最大;空间上,1961—2021年,随着干旱历时、烈度和烈度峰值的增加,“或”情况下多维干旱联合发生概率最高值区自北向南转移,“且”情况下多维干旱联合发生概率最高值区自南向北转移。 展开更多
关键词 气象干旱 游程理论 联合发生概率 COPULA函数 澜沧江-湄公河流域
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基于SPI-RRV指数中国气象干旱及其风险时空演变特征研究 被引量:3
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作者 杨肖丽 罗定 +4 位作者 叶周兵 谢灵枫 任立良 江善虎 袁山水 《水资源保护》 EI CSCD 北大核心 2024年第1期44-51,共8页
为全面揭示变化环境下我国多维气象干旱特征,耦合气象干旱指数(SPI)和可靠性-回弹性-脆弱性(RRV)指数,提出了一种基于SPI-RRV指数的干旱风险评价方法,定量评价了中国气象干旱及其风险的时空演变特征。结果表明:SPI-RRV指数具有特征稳定... 为全面揭示变化环境下我国多维气象干旱特征,耦合气象干旱指数(SPI)和可靠性-回弹性-脆弱性(RRV)指数,提出了一种基于SPI-RRV指数的干旱风险评价方法,定量评价了中国气象干旱及其风险的时空演变特征。结果表明:SPI-RRV指数具有特征稳定和时空可比性强的特点,能够较为准确地评估气象干旱风险时空演变特征;南方平均干旱栅格比、干旱月占比和频次大于北方,湿润区和半湿润区干旱历时短、烈度大,半干旱区和干旱区干旱历时长、烈度相对较小;干旱高风险区转移具有显著年代际变化规律,空间上从西北向西南地区转移。 展开更多
关键词 气象干旱 标准化降水指数 可靠性-回弹性-脆弱性指数 干旱风险
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水资源-能源-粮食-生态系统耦合协调及驱动力分析 被引量:2
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作者 杨明明 朱永楠 +2 位作者 赵勇 杨文静 樊煜 《人民黄河》 CAS 北大核心 2024年第3期58-63,共6页
为加深对我国水资源、能源、粮食、生态系统协同演变趋势的认识,构建水资源-能源-粮食-生态多维系统指标体系,运用耦合协调度模型对我国2005—2020年水资源-能源-粮食-生态系统耦合协调度进行评价,并采用多因素归因分析法进行驱动力分... 为加深对我国水资源、能源、粮食、生态系统协同演变趋势的认识,构建水资源-能源-粮食-生态多维系统指标体系,运用耦合协调度模型对我国2005—2020年水资源-能源-粮食-生态系统耦合协调度进行评价,并采用多因素归因分析法进行驱动力分析。结果表明:我国水资源-能源-粮食-生态系统耦合协调度从2005年的0.55增长到2020年的0.84,各地区耦合协调度从勉强协调发展水平过渡到中级协调发展水平,各子系统对耦合协调度上升的驱动分别经历了由粮食子系统到生态子系统再到水资源子系统主导的过程;能源子系统的贡献率虽然比较小,但是未来可能是各地区提升水资源-能源-粮食-生态系统多维系统协调发展水平的突破口。 展开更多
关键词 水资源-能源-粮食-生态 耦合协调度 多因素归因分析 驱动力
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深部煤储层孔裂隙结构对煤层气赋存的影响-以鄂尔多斯盆地东缘大宁-吉县区块为例 被引量:1
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作者 邓泽 王红岩 +3 位作者 姜振学 丁蓉 李永洲 王涛 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第8期106-123,共18页
深部煤储层孔隙–裂缝结构对深部煤层气资源潜力评价和勘探开发具有重要意义。选取鄂尔多斯盆地东缘大宁–吉县区块DJ57井本溪组5个煤岩样品为研究对象,在煤岩煤质参数测试的基础上,采用气体吸附法、高压压汞法和微米CT扫描等测试手段,... 深部煤储层孔隙–裂缝结构对深部煤层气资源潜力评价和勘探开发具有重要意义。选取鄂尔多斯盆地东缘大宁–吉县区块DJ57井本溪组5个煤岩样品为研究对象,在煤岩煤质参数测试的基础上,采用气体吸附法、高压压汞法和微米CT扫描等测试手段,对深部煤储层中的纳米级孔隙-微米级裂缝进行多尺度定量表征,综合评价不同尺度的孔裂隙结构特征。再结合渗透率和甲烷等温吸附试验,探讨了微观孔裂隙对深部煤储层中煤层气的赋存和渗流的影响。研究结果表明:基于多种孔隙表征方法对深部煤储层孔裂隙进行多尺度定量表征,其孔裂隙体积分布类型主要以“U”型为主,呈现出微孔与微裂缝并存双峰态,主要集中在0.3~1.5 nm和>100μm的范围内。其中,微孔(<2 nm)、介孔(2~50 nm)、宏孔(50 nm~10μm)和微裂缝(>10μm)体积平均分别占总孔裂隙体积的80.18%,6.70%,1.65%和11.47%。随着微孔发育而吸附气量呈增大的趋势,微孔可以提供大量吸附点位,为深部煤层气的吸附和赋存提供场所。随着微裂缝发育而游离气量呈增大的趋势,微裂缝可以提供大量储集空间,为深部煤层气的富集提供空间条件。此外,微裂缝在三维空间中相互连通,形成网状结构,连通性强。随着微裂缝越发育,煤储层渗透率越大,微裂缝增强了煤层气的渗流能力。纳米级孔隙和微米级裂隙发育特征分别控制着深部煤层气吸附能力和开发潜力。 展开更多
关键词 深部煤层气 孔隙-裂缝 全尺度表征 大宁-吉县区块
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基于UPLC-QTOF-MS解析苦荞黄酮组成及药理学网络分析 被引量:1
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作者 董玲 张凤菊 +5 位作者 赵驰 杨文渊 韩梅 黄巧莲 阿木布哈 李治华 《核农学报》 CAS CSCD 北大核心 2024年第5期911-918,共8页
为优化苦荞黄酮提取工艺并明确其具体成分结构和含量及药理作用,本研究以四川省凉山彝族自治州甘洛县优质苦荞为研究对象,对超声提取苦荞黄酮工艺进行了优化,采用超高效液相色谱-四级杆-飞行时间质谱(UPLC-QTOF-MS)对主要黄酮成分进行... 为优化苦荞黄酮提取工艺并明确其具体成分结构和含量及药理作用,本研究以四川省凉山彝族自治州甘洛县优质苦荞为研究对象,对超声提取苦荞黄酮工艺进行了优化,采用超高效液相色谱-四级杆-飞行时间质谱(UPLC-QTOF-MS)对主要黄酮成分进行结构鉴定,并采用超高效液相色谱-三重四级杆质谱联用仪对鉴定到的黄酮进行准确定量,同时利用中药系统药理学(TCMSP)系统分析其网络药理学特性。结果表明,超声辅助乙醇提取苦荞黄酮的最优条件为乙醇浓度90%(V/V)、超声功率140 W、超声温度70℃、超声时间60 min、提取溶剂与苦荞原料比50∶1(mL·g^(-1)),该条件下,提取液中共鉴定到黄酮16种,其中芦丁、表儿茶素和儿茶素含量分别达到115.81、72.99和23.08μg·mL^(-1)。这16种黄酮在防治心血管疾病、慢性炎症性疾病上具有重要作用。本研究可为苦荞精深加工综合利用尤其是功能性苦荞产品开发利用奠定基础。 展开更多
关键词 苦荞 黄酮 超高效液相色谱-四级杆-飞行时间质谱 芦丁
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