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Quality Standard for Euonymi Grandiflorus Caulis and Folium
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作者 Qi CUI yuanlin KONG +6 位作者 Mingkang FENG Riluo FENG Luha AYI Ying LI Chen CHEN Wenbing LI yuan liu 《Medicinal Plant》 CAS 2022年第4期14-18,共5页
[Objectives]To establish the quality standard for Euonymi Grandiflorus Caulis and Folium.[Methods]Qualitative identification was performed by methods of origin identification,microscopic identification and thin layer ... [Objectives]To establish the quality standard for Euonymi Grandiflorus Caulis and Folium.[Methods]Qualitative identification was performed by methods of origin identification,microscopic identification and thin layer chromatography(TLC);the moisture,total ash,acid-insoluble ash,and extract were detected using the method in the Chinese Pharmacopoeia(2020 Edition),and the contents of quercetin and kaempferol were determined by High Performance Liquid Chromatography(HPLC).[Results]The leaves of Euonymi Grandiflorus were subleathery,narrow and long elliptic or narrow obovate with cyme,and capsules were often with narrow wing ridge.Characteristics of microscopic identification were significant.Calcium oxalate cluster crystals,cubic crystals,inlaid parenchyma cells,starch granules,stomata,and fiber bundles could be observed.A TLC method for identification of Euonymi Grandiflorus Caulis and Folium was established.The contents of water,total ash,acid-insoluble ash were not higher than 13%,9%,12%,respectively;the extract were no less were not higher than 13%,9%,12%and 17%in ten batches of samples,respectively;the sum of quercetin and kaempferol were no less than 0.20%.[Conclusions]The quality standard of Euonymi Grandiflorus Caulis and Folium were established through the research.This method is accurate,specific,and reproducible and can be used for the quality control of Euonymi Grandiflorus Caulis and Folium. 展开更多
关键词 Euonymi Grandiflorus Caulis and Folium QUERCETIN KAEMPFEROL Quality standard(draft)
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纳木措流域岸边带湿地产甲烷古菌群落多样性与分布特征 被引量:1
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作者 刘源 杜剑卿 +2 位作者 马丽媛 杨刚 田建卿 《生物多样性》 北大核心 2025年第1期67-80,共14页
高寒河流型湿地生态系统是甲烷排放的重要区域。产甲烷古菌是湿地生境中甲烷产生的主要来源之一,其群落组成变化显著影响全球碳循环过程。然而,高寒河流型湿地产甲烷古菌群落的组成与分布特征尚不明确。因此,本研究以青藏高原纳木措湖... 高寒河流型湿地生态系统是甲烷排放的重要区域。产甲烷古菌是湿地生境中甲烷产生的主要来源之一,其群落组成变化显著影响全球碳循环过程。然而,高寒河流型湿地产甲烷古菌群落的组成与分布特征尚不明确。因此,本研究以青藏高原纳木措湖尼亚曲流域为研究对象,利用mcr A基因扩增子测序技术,对横向(岸边带湿地、过渡带、高寒草甸)和纵向(4,980 m、4,843 m、4,777 m、4,752 m 4个海拔梯度)两个维度上的土壤产甲烷古菌进行分析,探讨其多样性、群落结构及分布模式。结果表明,从岸边带湿地至过渡带再到高寒草甸,产甲烷古菌群落的α多样性逐渐降低,岸边带湿地群落组成显著不同于高寒草甸和过渡带。在所有样点中,氢营养型甲烷杆菌属(Methanobacterium)是最主要的产甲烷古菌(高寒草甸、过渡带和岸边带湿地的平均相对丰度依次为45.78%、42.90%及34.17%)。中性群落模型表明,随机过程是岸边带湿地产甲烷古菌群落构建的主要驱动因素,但随机过程对高寒草甸及过渡带群落贡献较少。FEAST溯源分析表明,横向维度上,高寒草甸和过渡带对岸边带湿地产甲烷古菌群落的贡献率分别为17.62%和13.04%;纵向维度上,低海拔(样点S4)岸边带湿地产甲烷古菌群落主要由河流上游岸边带湿地(49.71%)和高寒草甸(21.45%)输入,表明高寒草甸是岸边带湿地产甲烷古菌群落的重要物种库。本研究揭示了高寒流域土壤产甲烷古菌群落的多样性组成及分布模式,对理解高寒生态系统功能具有重要意义。 展开更多
关键词 岸边带湿地 产甲烷古菌 群落组装 微生物来源
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浅谈2024年诺贝尔化学奖——通过计算模拟和人工智能破译蛋白质结构的奥秘 被引量:3
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作者 王冯璋 刘源 王初 《大学化学》 2025年第1期75-81,共7页
蛋白质是生命活动的主要承担者和执行者,蛋白质的三维结构与其生物学功能息息相关。2024年诺贝尔化学奖的一半奖项授予了DeepMind公司的DemisHassabis博士和JohnJumper博士,以表彰他们在蛋白质结构预测领域的突破性贡献;另一半奖项则授... 蛋白质是生命活动的主要承担者和执行者,蛋白质的三维结构与其生物学功能息息相关。2024年诺贝尔化学奖的一半奖项授予了DeepMind公司的DemisHassabis博士和JohnJumper博士,以表彰他们在蛋白质结构预测领域的突破性贡献;另一半奖项则授予了华盛顿大学的David Baker教授,以表彰他在蛋白质计算设计领域的系统性研究。本文简要回顾了蛋白质结构预测与设计这两个互逆问题研究历程的重点事件,并对它们的前沿应用进行了展望。 展开更多
关键词 诺贝尔化学奖 蛋白质折叠 蛋白质结构预测 蛋白质计算设计 ROSETTA AlphaFold
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超声检测羊水泥联合宫颈长度及宫颈前角预测妊娠结局的临床价值
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作者 曹晓辉 杜学文 +3 位作者 刘森容 袁流 杨敬红 邓素梅 《临床超声医学杂志》 2025年第6期521-525,共5页
目的探讨经阴道超声检测羊水泥联合宫颈长度及宫颈前角在预测孕妇妊娠结局中的临床价值。方法选取在我院接受常规产前检查的386例孕妇,根据妊娠结局将其分为妊娠正常组247例和妊娠不良组139例,应用经阴道超声测量宫颈长度和宫颈前角,并... 目的探讨经阴道超声检测羊水泥联合宫颈长度及宫颈前角在预测孕妇妊娠结局中的临床价值。方法选取在我院接受常规产前检查的386例孕妇,根据妊娠结局将其分为妊娠正常组247例和妊娠不良组139例,应用经阴道超声测量宫颈长度和宫颈前角,并观察有无羊水泥,比较两组上述检查结果的差异。采用Logistic回归分析筛选预测不良妊娠结局的独立影响因素;绘制受试者工作特征(ROC)曲线分析其单独及联合应用预测不良妊娠结局的诊断效能。结果妊娠不良组宫颈长度小于妊娠正常组,宫颈前角、羊水泥阳性占比均大于妊娠正常组,差异均有统计学意义(均P<0.001)。Logistic回归分析显示,宫颈长度、宫颈前角、羊水泥均为预测不良妊娠结局的独立危险因素(OR=2.511、2.632、3.658,均P<0.05)。ROC曲线分析显示,宫颈长度、宫颈前角、羊水泥预测不良妊娠结局的曲线下面积(AUC)分别为0.793、0.811、0.712(均P<0.001),三者联合应用的AUC为0.881(95%可信区间:0.815~0.959,P<0.001),高于其单独应用,差异均有统计学意义(均P<0.05);三者联合应用的灵敏度和特异度分别为85.61%和88.67%。结论羊水泥联合宫颈长度及宫颈前角在预测孕妇妊娠结局中具有一定的临床价值。 展开更多
关键词 超声检查 羊水泥 宫颈长度 宫颈前角 妊娠结局
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Antibiotic resistance of Helicobacter pylori and related risk factors in Hunan Province:A multicenter study 被引量:2
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作者 Jie Xie Ming-Lin Zhang +4 位作者 Min Guo Jian-Guo Li yuan liu Hong-Hui Chen Fen Wang 《World Journal of Gastroenterology》 2025年第12期62-70,共9页
BACKGROUND Antibiotic resistance is a key factor influencing the treatment outcomes of Helicobacter pylori(H.pylori)infection.The antibiotic resistance spectrum of H.pylori varies in different regions.We investigated ... BACKGROUND Antibiotic resistance is a key factor influencing the treatment outcomes of Helicobacter pylori(H.pylori)infection.The antibiotic resistance spectrum of H.pylori varies in different regions.We investigated the current status of antibiotic resistance of H.pylori in Hunan Province and analyzed the factors related to such resistance to provide strategies for the accurate clinical treatment of H.pylori infection.AIM To understand the antibiotic resistance of H.pylori in Hunan Province and provide guidance for the clinical treatment of H.pylori infection.METHODS This study selected patients who underwent gastroscopy in five hospitals in Hunan Province from April 2022 to April 2023.The sensitivity of H.pylori to clarithromycin,levofloxacin,metronidazole,amoxicillin,furazolidone,and tetracycline was detected using the Agar dilution method.RESULTS H.pylori strains from a total of 566 patients were isolated and identified.The resistance rates of H.pylori strains to clarithromycin,levofloxacin,metronidazole,amoxicillin,furazolidone,and tetracycline were 49.2%,37.8%,76.1%,2.3%,1.4%,and 0.7%,respectively.The resistance rates to clarithromycin,levofloxacin,and metronidazole were high in the four regions of Hunan Province,and the overall resistance rates in central Hunan Province were higher than those in other regions.The resistance rates of H.pylori strains to clarithromycin and levofloxacin were significantly different among the different age groups(P<0.05),with the elderly group having a higher resistance rate than the young group.The resistance rate of H.pylori strains to clarithromycin was greater in patients with atrophic gastritis,and the resistance rate to levofloxacin was the lowest in patients with peptic ulcers.CONCLUSION The resistance rate of H.pylori to amoxicillin,clarithromycin,and metronidazole is high in Hunan Province.Age,stomach disease,and H.pylori reinfection may affect the antibiotic resistance of H.pylori. 展开更多
关键词 Helicobacter pylori Antibiotic resistance Stomach disease Resistance risk MULTICENTER
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老年维持性血液透析患者药物素养现状及影响因素研究
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作者 王秋静 刘菁 +4 位作者 徐颖 袁柳 韩瑞雪 黄艳 马竹怡 《护理管理杂志》 2025年第11期956-960,共5页
目的探讨老年维持性血液透析患者药物素养现状,并分析其影响因素。方法采用一般资料调查表、药物素养调查问卷和合理用药自我效能量表对宿迁市5所综合医院的234例老年维持性血液透析患者进行调查。结果老年维持性血液透析患者药物素养... 目的探讨老年维持性血液透析患者药物素养现状,并分析其影响因素。方法采用一般资料调查表、药物素养调查问卷和合理用药自我效能量表对宿迁市5所综合医院的234例老年维持性血液透析患者进行调查。结果老年维持性血液透析患者药物素养得分为3.00(2.00,6.00)分,合理用药自我效能得分为(26.29±7.05)分;药物素养与合理用药自我效能呈正相关(r=0.442,P<0.001);多元线性回归分析显示,年龄、文化程度、用药种类、家庭月收入、合理用药自我效能是老年维持性血液透析患者药物素养的影响因素(P<0.05)。结论老年维持性血液透析患者药物素养处于中等水平,有待进一步提高。建议管理者实施针对性干预策略,以提升老年维持性血液透析患者药物素养,保障其用药安全。 展开更多
关键词 老年人 患者 血液透析 药物素养 合理用药自我效能 护理 影响因素
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Machine learning of pyrite geochemistry reconstructs the multi-stage history of mineral deposits 被引量:1
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作者 Pengpeng Yu yuan liu +5 位作者 Hanyu Wang Xi Chen Yi Zheng Wei Cao Yiqu Xiong Hongxiang Shan 《Geoscience Frontiers》 2025年第3期81-93,共13页
The application of machine learning for pyrite discrimination establishes a robust foundation for constructing the ore-forming history of multi-stage deposits;however,published models face challenges related to limite... The application of machine learning for pyrite discrimination establishes a robust foundation for constructing the ore-forming history of multi-stage deposits;however,published models face challenges related to limited,imbalanced datasets and oversampling.In this study,the dataset was expanded to approximately 500 samples for each type,including 508 sedimentary,573 orogenic gold,548 sedimentary exhalative(SEDEX)deposits,and 364 volcanogenic massive sulfides(VMS)pyrites,utilizing random forest(RF)and support vector machine(SVM)methodologies to enhance the reliability of the classifier models.The RF classifier achieved an overall accuracy of 99.8%,and the SVM classifier attained an overall accuracy of 100%.The model was evaluated by a five-fold cross-validation approach with 93.8%accuracy for the RF and 94.9%for the SVM classifier.These results demonstrate the strong feasibility of pyrite classification,supported by a relatively large,balanced dataset and high accuracy rates.The classifier was employed to reveal the genesis of the controversial Keketale Pb-Zn deposit in NW China,which has been inconclusive among SEDEX,VMS,or a SEDEX-VMS transition.Petrographic investigations indicated that the deposit comprises early fine-grained layered pyrite(Py1)and late recrystallized pyrite(Py2).The majority voting classified Py1 as the VMS type,with an accuracy of RF and SVM being 72.2%and 75%,respectively,and confirmed Py2 as an orogenic type with 74.3% and 77.1%accuracy,respectively.The new findings indicated that the Keketale deposit originated from a submarine VMS mineralization system,followed by late orogenic-type overprinting of metamorphism and deformation,which is consistent with the geological and geochemical observations.This study further emphasizes the advantages of Machine learning(ML)methods in accurately and directly discriminating the deposit types and reconstructing the formation history of multi-stage deposits. 展开更多
关键词 Machine learning Random forest Support vector machine PYRITE Multi-stage genesis Keketale deposit
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Vibration reduction mechanism and characteristics evaluation of active elastic support/dry friction damper 被引量:1
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作者 Siji WANG Dafang LIN +2 位作者 Quankun LI Jiayao CHEN yuan liu 《Chinese Journal of Aeronautics》 2025年第4期333-348,共16页
This paper studies the coupling mechanism between the nonlinear stiffness and damping coefficients of Active Elastic Support/Dry Friction Damper(AESDFD)and rotor system.First,parameters for evaluating the vibration re... This paper studies the coupling mechanism between the nonlinear stiffness and damping coefficients of Active Elastic Support/Dry Friction Damper(AESDFD)and rotor system.First,parameters for evaluating the vibration reduction characteristics are proposed to facilitate the design of the AESDFD.To achieve this,the nonlinear friction force is initially represented as equivalent stiffness and damping coefficients,based on the ball-plate friction model.Second,three evaluation parameters—optimal slipping displacement,loss factor,and controllability—are proposed to reveal the vibration reduction characteristics of the AESDFD,alongside determining the optimal normal force.Subsequently,the finite element method,in conjunction with the ball-plate friction model,is introduced to formulate the governing equation of a low-pressure rotor system equipped with AESDFDs.The steady-state responses of the AESDFDs-rotor system are solved using the harmonic balance method combined with an efficient iteration method.Finally,the solutions are validated on the AESDFDs-rotor system both numerically and experimentally.The results indicate that controllability effectively assesses the vibration reduction performance of the AESDFD and is relatively insensitive to variations in low normal force.Away from the critical speed,the AESDFD suppresses vibration by altering the resonance position of the rotor system through its stiffness coefficient.Near the critical speed,vibration reduction is achieved primarily through energy dissipation by the damping coefficient.If the loss factor is less than one,the stiffness coefficient can diminish the vibration reduction effect of the damping coefficient.Notably,the optimal normal force of the AESDFD achieves optimal vibration reduction effect.This study reveals that changes in rotor system unbalance do not affect the vibration reduction characteristics of the AESDFD,with the same upper limit to the vibration reduction effect of the AESDFD. 展开更多
关键词 Active dry friction damper Low-pressure rotor system Vibration analysis Stiffness and damping coefficients Evaluation parameters Finite element method
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Fault-tolerant control strategies for tilt-rotor aerial-aquatic vehicles:Design and implementation 被引量:1
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作者 Sihuan Wu Sifan Wu +3 位作者 Maosen Shao Zhilin He yuan liu Jinxiu Zhang 《Defence Technology(防务技术)》 2025年第9期274-293,共20页
The cross-domain capabilities of aerial-aquatic vehicles(AAVs)hold significant potential for future airsea integrated combat operations.However,the failure rate of AAVs is higher than that of unmanned systems operatin... The cross-domain capabilities of aerial-aquatic vehicles(AAVs)hold significant potential for future airsea integrated combat operations.However,the failure rate of AAVs is higher than that of unmanned systems operating in a single medium.To ensure the reliable and stable completion of tasks by AAVs,this paper proposes a tiltable quadcopter AAV to mitigate the potential issue of rotor failure,which can lead to high-speed spinning or damage during cross-media transitions.Experimental validation demonstrates that this tiltable quadcopter AAV can transform into a dual-rotor or triple-rotor configuration after losing one or two rotors,allowing it to perform cross-domain movements with enhanced stability and maintain task completion.This enhancement significantly improves its fault tolerance and task reliability. 展开更多
关键词 Aerial-aquatic vehicle Tiltable quadcopter FAULT-TOLERANCE Cross-media operation
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针刺疗法联合热敏灸治疗肛瘘术后尿潴留的临床疗效观察
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作者 刘源 哈力甫·阿布拉 《中医学》 2025年第3期1101-1106,共6页
目的:本研究旨在探讨针刺疗法联合热敏灸治疗肛瘘术后尿潴留的临床疗效。方法:选取2024年1月至2024年6月期间,在乌鲁木齐市自治区人民医院收治的60例肛瘘术后尿潴留患者作为研究对象,采用随机数字表法将其分为对照组和试验组,每组30例... 目的:本研究旨在探讨针刺疗法联合热敏灸治疗肛瘘术后尿潴留的临床疗效。方法:选取2024年1月至2024年6月期间,在乌鲁木齐市自治区人民医院收治的60例肛瘘术后尿潴留患者作为研究对象,采用随机数字表法将其分为对照组和试验组,每组30例。对照组接受常规治疗,包括热敷小腹、听流水声以及心理疏导,并辅以甲硫酸新斯的明肌肉注射。试验组则采用针刺疗法与热敏灸相结合的治疗方案。通过对比两组患者的首次排尿时间、2小时内排尿总量、主要症状评分以及尿路感染发生率,评估两种治疗方案的临床疗效。结果:显示试验组的治疗总有效率显著高于对照组(P<0.05),且试验组的首次排尿时间更短、2 h排尿量更多、残余尿量更少,同时尿路感染发生率也低于对照组(P<0.05)。结论:针刺疗法联合热敏灸治疗肛瘘术后尿潴留方面具有显著疗效,能够缩短患者首次排尿时间,2 h内排尿总量大于400 ml,提高患者控尿能力,预防泌尿系感染,提高患者生活质量,值得临床推广。 展开更多
关键词 肛瘘术后尿潴留 针刺疗法 热敏灸
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Enhanced 3D printing and crack control in melt-grown eutectic ceramic composites with high-entropy alloy doping 被引量:1
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作者 Zhonglin Shen Haijun Su +10 位作者 Minghui Yu Yinuo Guo yuan liu Hao Jiang Xiang Li Dong Dong Peixin Yang Jiatong Yao Min Guo Zhuo Zhang Wei Ren 《Journal of Materials Science & Technology》 2025年第6期64-78,共15页
As a 3D printing method,laser powder bed fusion(LPBF)technology has been extensively proven to offer significant advantages in fabricating complex structured specimens,achieving ultra-fine microstructures,and enhancin... As a 3D printing method,laser powder bed fusion(LPBF)technology has been extensively proven to offer significant advantages in fabricating complex structured specimens,achieving ultra-fine microstructures,and enhancing performances.In the domain of manufacturing melt-grown oxide ceramics,it encounters substantial challenges in suppressing crack defects during the rapid solidification process.The strategic integration of high entropy alloys(HEA),leveraging the significant ductility and toughness into ceramic powders represents a major innovation in overcoming the obstacles.The ingenious doping of HEA parti-cles preserves the eutectic microstructures of the Al_(2)O_(3)/GdAlO_(3)(GAP)/ZrO_(2)ceramic composite.The high damage tolerance of the HEA alloy under high strain rates enables the absorption of crack energy and alleviation of internal stresses during LPBF,effectively reducing crack initiation and growth.Due to in-creased curvature forces and intense Marangoni convection at the top of the molt pool,particle collision intensifies,leading to the tendency of HEA particles to agglomerate at the upper part of the molt pool.However,this phenomenon can be effectively alleviated in the remelting process of subsequent layer de-position.Furthermore,a portion of the HEA particles partially dissolves and sinks into the molten pool,acting as heterogeneous nucleation particles,inducing the formation of equiaxed eutectic and leading pri-mary phase nucleation.Some HEA particles diffuse into the lamellar ternary eutectic structures,further promoting the refinement of eutectic microstructures due to increased undercooling.The innovative dop-ing of HEA particles has effectively facilitated the fabrication of turbine-structured,conical,and cylindrical ternary eutectic ceramic composite specimens with diameters of about 70 mm,demonstrating significant developmental potential in the field of ceramic composite manufacturing. 展开更多
关键词 Laser powder bed fusion Eutectic ceramic composite High entropy alloy doping
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Solid-state reaction synthesis and chemical stability studies in Nd-doped zirconolite-rich ceramics 被引量:6
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作者 Dan Yin Kuibao Zhang +4 位作者 Le Peng Zongsheng He yuan liu Haibin Zhang Xirui Lu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第5期492-498,共7页
In this study, Nd-bearing zirconolite-rich ceramics were prepared by solid-state reaction process using CaF2,ZrO2, Ti,TiO2, Fe2 O3 and Nd2O3 as the raw materials. Neodymium was used as trivalent actinide surrogate and... In this study, Nd-bearing zirconolite-rich ceramics were prepared by solid-state reaction process using CaF2,ZrO2, Ti,TiO2, Fe2 O3 and Nd2O3 as the raw materials. Neodymium was used as trivalent actinide surrogate and designed to substitute the Ca and Zr sites of zirconolite with general stoichiometry of Ca1-xZr1-xNd2 xTi2O7(0≤x≤0.3). Density of Fe-Nd-O sample reaches a maximum value of 4.13 g/cm^2 after being sintered at 1325 ℃ for 42 h. Three major phases, namely zirconolite, perovskite and pseudobrookite, are observed in all these samples. The EDX result shows that Nd2O3 can be successfully incorporated into the lattice structure of the prepared zirconolite-rich minerals and replace the Ca sites of zirconolite and perovskite with Fe3+ as the charge-compensating ion. Furthermore, the thermal conductivities are all in the range of 1.51-1.67 W/(m·K). The normalized elemental leaching rates of Ca and Nd in the Fe-Nd-0.2 sample keep in low values of 6.20 × 10^-2 and 4.86 × 10^-4 g/(m^2·d) after 42 d. 展开更多
关键词 ZIRCONOLITE PEROVSKITE Pseudobrookite ND2O3 Chemical stability Rare earths
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父母为高度近视的新生儿眼部生物学参数特征分析
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作者 袁柳 何勇川 《中华实验眼科杂志》 北大核心 2025年第6期528-534,共7页
目的分析父母为高度近视的足月新生儿眼部生物学参数特征。方法采用横断面研究,收集2021年9月至2023年12月在重庆爱尔儿童眼科医院儿童眼保健门诊进行眼底筛查的新生儿120例120眼,均纳入右眼数据进行分析。将纳入新生儿根据父母是否有... 目的分析父母为高度近视的足月新生儿眼部生物学参数特征。方法采用横断面研究,收集2021年9月至2023年12月在重庆爱尔儿童眼科医院儿童眼保健门诊进行眼底筛查的新生儿120例120眼,均纳入右眼数据进行分析。将纳入新生儿根据父母是否有高度近视病史分为父母高度近视组(父母双方或一方为高度近视者)60例60眼和父母非高度近视组60例60眼,并将父母高度近视组亚分为父母双方高度近视组20例20眼和父母一方高度近视组40例40眼。依据父母等效球镜度(SE)将其分为高度近视组80例80眼、低中度近视组68例68眼和正视组92例92眼。所有新生儿出生后28 d内进行检查,采用睫状肌麻痹后检影验光并计算SE,采用手持电脑验光仪测量新生儿角膜曲率,采用眼部A型超声测量眼轴长度(AL),采用手持眼压计测量眼压;分别采用手持电脑验光仪和手持眼压计测量新生儿父母屈光度和眼压,并记录父母高度近视病史情况。比较父母高度近视组与父母非高度近视组、父母双方高度近视组与父母一方高度近视组新生儿的SE、AL、平均角膜曲率和眼压,并分析各参数的相关性,比较父母不同程度屈光度组眼压差异。结果父母高度近视组的新生儿SE为(+2.89±0.81)D,明显低于父母非高度近视组的(+3.86±0.85)D,差异有统计学意义(t=4.347,P<0.001);父母高度近视组的新生儿AL为(17.17±0.41)mm,明显长于父母非高度近视组的(16.78±0.42)mm,差异有统计学意义(t=3.491,P=0.001);2个组新生儿平均角膜曲率和眼压比较,差异均无统计学意义(t=0.404、0.688,均P>0.05)。在父母高度近视组的新生儿中,父母双方高度近视组新生儿的远视屈光度较父母一方高度近视组新生儿的远视屈光度更低、AL更长,差异均有统计学意义(t=7.386、6.203,均P<0.001)。Pearson相关分析结果显示,新生儿SE与AL呈负相关(r=-0.868,P<0.001),AL与出生胎龄、出生体质量、出生身长均呈正相关(r=0.864、0.820、0.874,均P<0.05)。高度近视组、低中度近视组和正视组新生儿父母平均眼压分别为(16.45±0.67)、(15.21±0.53)和(14.86±0.49)mmHg(1 mmHg=0.133 kPa),总体比较差异有统计学意义(F=2.764,P=0.021),其中高度近视组眼压高于低中度近视组和正视组,差异均有统计学意义(均P<0.05)。结论与非高度近视父母的新生儿相比,高度近视父母的足月新生儿的远视储备量较低且AL较长。 展开更多
关键词 高度近视 新生儿 眼轴长度 角膜曲率 屈光度
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64×64 InGaAs/InP三维成像激光焦平面探测器 被引量:16
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作者 李潇 石柱 +5 位作者 代千 覃文治 寇先果 袁鎏 刘期斌 黄海华 《红外与激光工程》 EI CSCD 北大核心 2018年第8期107-111,共5页
针对900~1 700 nm波长无扫描激光三维成像雷达的需求,研制了一种规模为64×64的线性模式雪崩焦平面阵列(LM-APD-FPA),它由InGaAs/InP雪崩光电二极管阵列与CMOS专用读出电路(ASIC)组成。该器件采用飞行时间(TOF)测距的方式工作,APD... 针对900~1 700 nm波长无扫描激光三维成像雷达的需求,研制了一种规模为64×64的线性模式雪崩焦平面阵列(LM-APD-FPA),它由InGaAs/InP雪崩光电二极管阵列与CMOS专用读出电路(ASIC)组成。该器件采用飞行时间(TOF)测距的方式工作,APD光敏芯片将脉冲激光信号转化成脉冲光电流,读出电路对其进行放大、阈值比较后实现激光探测并在每个单元获取光脉冲的飞行时间,将其转化成二进制编码信号后串行输出。测试结果表明,64×64 LM-APD-FPA有效像元最小可探测光功率值约为400 nW,时间分辨率为1 ns。用该探测器在激光雷达系统上实现了无扫描单脉冲激光三维成像,表明了线性模式激光焦平面探测器可用于激光三维成像领域。 展开更多
关键词 焦平面阵列 线性模式 铟镓砷 飞行时间测距 三维成像
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Design and Implementation of GIS Data Production System for Expressway Video and Road Infostructure 被引量:2
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作者 yuan liu Jianhua liu Guoqiang Feng 《International Journal of Geosciences》 2021年第1期23-38,共16页
The expressway is necessary for the development of the modern transportation industry, and the level of expressway construction reflects the overall grade of national or regional economic development. In order to proc... The expressway is necessary for the development of the modern transportation industry, and the level of expressway construction reflects the overall grade of national or regional economic development. In order to process the expressway road property data information, based on the current mainstream Windows operating system, this study utilizes Geographic Information System (GIS) development technology, road video processing technology, and spatial data mining method to design and develop an expressway video and road infostructure GIS data production system. The system designs a multi-layer distributed application model in accordance with the ideas and methods of GIS engineering and the characteristics of road production data. In addition, according to the characteristics and specification requirements of basic geographic data, the road production database of spatial data and attribute data integrated storage is constructed by combining database and spatial data engine. Through the development of the GIS data production system for expressway video and road infostructure, various functions such as generation of road property data, dynamic management of road infostructure, and visualization of spatial information have been realized. The system focuses on improving the production efficiency and automation level of expressway production data and meet</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> the construction requirements for modernization, informatization, and intelligence of expressways. 展开更多
关键词 EXPRESSWAY GIS Road Infostructure VIDEO Road Property Data
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甲状腺功能测定在甲状腺癌诊断中的作用 被引量:12
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作者 何静妮 田忠 +3 位作者 郑黎强 岳阳阳 刘源 姚旭 《中国现代医学杂志》 CAS 2019年第24期54-59,共6页
目的评估甲状腺手术患者的甲状腺功能指标和超声检查,预测其与甲状腺癌的关系,以期寻求更好的术前诊断方法。方法回顾性分析2015年1月—2015年12月在中国医科大学附属盛京医院行甲状腺手术的患者,分析患者术前的甲状腺功能、彩色B超,结... 目的评估甲状腺手术患者的甲状腺功能指标和超声检查,预测其与甲状腺癌的关系,以期寻求更好的术前诊断方法。方法回顾性分析2015年1月—2015年12月在中国医科大学附属盛京医院行甲状腺手术的患者,分析患者术前的甲状腺功能、彩色B超,结合性别、年龄及最终病理结果,评估正常范围内的甲状腺功能指标对甲状腺癌的预测水平。结果最终纳入908例患者。其中,恶性结节患者244例,良性结节患者664例。患者性别构成、甲状腺素(T4)比较,差异无统计学意义(P>0.05);而年龄、血清促甲状腺激素(TSH)水平、三碘甲状腺原氨酸(T3)、甲状腺过氧化物酶抗体(TPOAb)阳性率及甲状腺球蛋白抗体(TgAb)阳性率比较,差异有统计学意义(P<0.05)。将TSH、T3水平四等分,随着TSH水平上升,T3水平降低,患者恶性率增加(P<0.05)。血清TSH在2个水平较高的四分位区间比最低水平的四分位区间患者患恶性肿瘤的风险更大[OR=2.410(95%CI:1.552,3.743)]、[OR=2.508(95%CI:1.613,3.899)]。甲状腺癌的患病风险与血清TSH呈正比。而T3在2个相对较低水平的第2和第4四分位区间比最高水平的四分位区间患恶性肿瘤的风险高[OR=2.410(95%CI:1.552,3.743)]、[OR=2.508(95%CI:1.613,3.899)]。绘制受试者工作特征曲线,测得临界值TSH=1.4861μIU/ml,T3=4.94 pmol/L。诊断实验中,T3分别联合TSH、TPOAb及TgAb,TSH分别联合TPOAb、TgAb的特异性较高。结论甲状腺功能参数可作为一种可靠的甲状腺乳头状癌的辅助诊断指标。 展开更多
关键词 甲状腺肿瘤 促甲状腺激素 甲状腺素 三碘甲状腺原氨酸
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基于SEER数据库分析老年胃癌患者内镜手术与传统术式的治疗效果及预后 被引量:8
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作者 万秀萍 翁慧斌 +5 位作者 林小花 刘媛 陈大军 林海 陈毓 丁小云 《中国内镜杂志》 2020年第5期7-14,共8页
目的基于SEER数据库分析老年胃癌(GC)患者内镜黏膜下剥离术(ESD)与传统术式的治疗效果及预后的影响因素。方法筛选2014年1月-2014年12月SEER数据库登记的ESD或传统术式治疗的老年T1期原发性GC患者,共865例。分析ESD与传统术式的手术效果... 目的基于SEER数据库分析老年胃癌(GC)患者内镜黏膜下剥离术(ESD)与传统术式的治疗效果及预后的影响因素。方法筛选2014年1月-2014年12月SEER数据库登记的ESD或传统术式治疗的老年T1期原发性GC患者,共865例。分析ESD与传统术式的手术效果,并分析预后的影响因素。结果865例患者男女比例为1.00∶0.64,29.02%和49.02%的患者合并营养不良(差)与合并慢性疾病,其中接受ESD和传统术式治疗者分别为406和459例,占46.94%和53.06%,5年总生存率为66.36%。ESD和传统术式治疗的老年患者治愈性切除率、完整性切除率和术后复发率比较,差异均无统计学意义(P>0.05);但与传统术式相比,ESD治疗者手术时间和术后住院时间短(P<0.05)、术中出血量少(P<0.05)、术中输血率低(P<0.05);ESD治疗者术后出血率、切口感染率、肺部感染率及总并发症发生率均明显低于传统术式(P<0.05)。单因素分析显示,性别、年龄、吸烟史、合并慢性疾病、原发病灶部位、肿瘤大小、病理类型及治疗方式,差异均无统计学意义(P>0.05);而营养状态、分化程度、淋巴结转移与否、术中是否输血和术后是否复发比较,差异均有统计学意义(P<0.05);多因素COX回归分析显示,营养差(RR=1.640,95%CI:1.207~2.235)、中低分化(RR=1.510,95%CI:1.113~2.049)、淋巴结转移(RR=1.412,95%CI:1.013~1.927)、术中输血(RR=1.394,95%CI:1.157~1.679)、术后复发(RR=3.529,95%CI:3.003~4.147)均为影响老年T1期原发性GC患者预后的独立危险因素(P<0.05)。结论ESD与传统术式治疗老年GC患者的临床效果相当,但前者具有手术时间短、出血量少、并发症发生率低和术后恢复快的优点,预后的影响因素有营养状态、分化程度、淋巴结转移、术中输血和术后复发。 展开更多
关键词 SEER数据库 老年 胃癌 内镜黏膜下剥离术 预后
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苯并噻唑酮类热活化延迟荧光材料的合成及其光电性能研究 被引量:11
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作者 张越华 聂飞 +5 位作者 周路 王晓烽 刘源 霍延平 陈文铖 赵祖金 《有机化学》 SCIE CAS CSCD 北大核心 2023年第11期3876-3887,共12页
以苯并噻唑-2-基(苯基)甲酮作为受体,具有强给电子能力的吩噁嗪和吩噻嗪作为给体构筑给体-受体(D-A)型分子,设计合成了两种具有聚集诱导发光(AIE)特性的热活化延迟荧光(TADF)红光材料3和4,并对它们的热稳定性、电化学性质、单晶结构、... 以苯并噻唑-2-基(苯基)甲酮作为受体,具有强给电子能力的吩噁嗪和吩噻嗪作为给体构筑给体-受体(D-A)型分子,设计合成了两种具有聚集诱导发光(AIE)特性的热活化延迟荧光(TADF)红光材料3和4,并对它们的热稳定性、电化学性质、单晶结构、光物理性质和电致发光性能进行了系统研究.两种化合物具有较小的单三线态能级差(ΔEST,0.04和0.16 eV)以及微秒级延迟寿命(0.63和1.30μs),表现出明显的TADF特性.通过对比化合物在粉末状态下研磨前后的发射光谱,发现化合物4具有明显的力致变色发光现象.在纯薄膜下,两种化合物的发射峰分别为683和654 nm,光致发光量子产率(PLQY)分别为0.8%和3.6%.基于化合物3和4的非掺杂有机发光二极管(OLED)器件,均获得了纯红光发射(662和652 nm),器件的最大外量子效率(EQE)分别为0.15%和0.34%.虽然基于这两种化合物的器件发光效率有待提升,但它们的合成过程简便,能为开发苯并噻唑酮类TADF红光材料提供一定的启发. 展开更多
关键词 聚集诱导发光(AIE)特性 热活化延迟荧光(TADF)红光材料 力致变色发光 苯并噻唑酮类
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EGFR/Vimentin/Folic Acid磁球检测肺癌循环肿瘤细胞初探 被引量:3
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作者 李国雷 王赟 +5 位作者 谭国梁 刘远 徐曌 冯浩 兴伟 徐志峰 《中国肺癌杂志》 CAS CSCD 北大核心 2020年第5期351-359,共9页
背景与目的循环肿瘤细胞(circulating tumor cell, CTC)在肺癌的筛查及预后方面发挥着重要的作用,但较低的CTC分离效率和特异性对其临床应用有着明显的制约,本研究旨在探讨非小细胞肺癌(non-small cell lung cancer, NSCLC)患者CTC的新... 背景与目的循环肿瘤细胞(circulating tumor cell, CTC)在肺癌的筛查及预后方面发挥着重要的作用,但较低的CTC分离效率和特异性对其临床应用有着明显的制约,本研究旨在探讨非小细胞肺癌(non-small cell lung cancer, NSCLC)患者CTC的新型高效分离方法,以期达到对NSCLC的早期诊断的目的。方法采用薄膜法制备表皮生长因子受体(epidermal growth factor receptor, EGFR)、波形蛋白(Vimentin)和叶酸(folic acid, FA)三种免疫脂质磁球,表征后通过细胞系进行分选方案的探索,构建对NSCLC CTC的最优分选方案,初步研究了其在临床上的应用价值。结果 EGFR、Vimentin和FA磁球磁球单独和联合使用对肺癌细胞株的平均捕获效率分别为78.0%、79.0%、82.0%和91.0%;在60例肺癌患者中,以每7.5 mL血液2个CTC为cutoff值,EGFR、Vimentin、FA磁球单独和联合使用阳性率分别为65.0%、33.3%、93.3%和100.0%,同时发现联合使用三种磁球检出的CTC数量与临床分期具有相关性(P<0.05)。结论联合使用三种磁球可以分离EGFR+、Vimentin+和FA+表达且形态完整的CTC,有利于的CTC相关下游分析,本研究提供了一种提高NSCLC CTC捕获效率的新方法,且验证了捕获的CTC计数方法可用于肺癌的辅助诊断。 展开更多
关键词 肺肿瘤 循环肿瘤细胞 EGFR VIMENTIN 叶酸 免疫磁球
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Characteristics and therapeutic strategies for familial gastrointestinal stromal tumors
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作者 yuan liu Xiao-Feng Li 《World Journal of Gastrointestinal Oncology》 2025年第3期13-18,共6页
This editorial discusses Wang et al's article on familial gastrointestinal stromal tumors(GISTs).We read with great interest this article concerning the diagnosis,treatment,and post-treatment management of patient... This editorial discusses Wang et al's article on familial gastrointestinal stromal tumors(GISTs).We read with great interest this article concerning the diagnosis,treatment,and post-treatment management of patients with familial GISTs.The actual incidence of GISTs may be underestimated due to diagnostic limitations and the long-term low-risk behavior of some GISTs.The molecular landscape of GISTs is primarily driven by mutations in the KIT and platelet-derived growth factor receptor alpha(PDGFRA)genes.A subset of GISTs without these mutations known as wild-type GISTs,may harbor other rare mutations,impacting their response to targeted therapies.Clinically,patients with GISTs present with nonspecific symptoms,often leading to delayed diagnosis.Genetic predispositions in familial GISTs provide insights into the genetic architecture and extragastrointestinal manifestations of GISTs.Management has evolved from surgical interventions to molecular-based therapies using tyrosine kinase inhibitors.The management of GISTs,especially in familial cases,requires a multidisciplinary approach.Cases of different gene mutations were reported in the same family,suggesting that incorporating genetic testing into routine clinical practice is crucial for the early identification of high-risk individuals and the implementation of tailored surveillance programs. 展开更多
关键词 Gastrointestinal stromal tumors KIT mutation Platelet-derived growth factor receptor alpha mutation Wild-type gastrointestinal stromal tumor Tyrosine kinase inhibitors Familial gastrointestinal stromal tumor syndromes Molecular characteristics Targeted therapy
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