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Molecular methods for detection of pathogenic viruses of respiratory tract——A review
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作者 Md.Shahidul Kabir 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2018年第5期237-244,共8页
Human respiratory system is harbored by a vast array of transient and normal microbial flora.A number of pathogenic viruses were diagnosed from samples in different occasions from mild to severe infections of respirat... Human respiratory system is harbored by a vast array of transient and normal microbial flora.A number of pathogenic viruses were diagnosed from samples in different occasions from mild to severe infections of respiratory tract.Molecular methods were developed for detection of these viruses during last two decades.Nucleic acid amplification methods were introduced for rapid and accurate diagnosis of pathogenic viruses.Multiplex detection systems were employed to identify a panel of pathogenic viruses,which requires specialized kits and instruments in some cases.This review summarizes different types of molecular approaches which were developed with time and applied for the detection of pathogenic viruses associated with infections of the respiratory system. 展开更多
关键词 Respiratory system VIRUS molecular method DETECTION
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Establishment of Molecular Biological Method for Identification of Bacteria by 16S rDNA and gyrB Gene
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作者 Xiaxia HOU Yunxia WANG +1 位作者 Cuizhi LI Zhiyong LU 《Asian Agricultural Research》 2023年第4期21-25,共5页
[Objectives]The paper was to establish a molecular biological method for identification of bacterial strains.[Methods]The thalli of standard bacterial strains existing in the laboratory were collected and genomic DNA ... [Objectives]The paper was to establish a molecular biological method for identification of bacterial strains.[Methods]The thalli of standard bacterial strains existing in the laboratory were collected and genomic DNA was extracted for amplification of 16S rDNA and gyrB gene.The 16S rDNA and gyrB gene sequences were obtained after sequencing.Sequences were aligned and analyzed via EzBioCloud and NCBI database,and phylogenetic trees were constructed to determine the species relationship of strains.Meantime,they were compared with known strains.[Results]This method could identify 5 standard strains accurately to the species level.The 16S rDNA and gyrB gene sequences were aligned and analyzed in EzBioCloud database and NCBI database.The strain with the max score was consistent with the known strain.And the query cover and ident were both above 99%.[Conclusions]The established molecular biological method for identification of bacterial strains by 16S rDNA and gyrB gene has good accuracy,which effectively solves the problem that the laboratory identification of bacteria relies on traditional methods and the accuracy can not be guaranteed,and further improves the identification ability of laboratory bacterial strains. 展开更多
关键词 16S rDNA GYRB Bacterial identification molecular biological method
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COMPUTERIZED SIMULATION OF MOLTEN SALT SOLUTION OF Li,KF,Cl SYSTEM BY MOLECULAR DYNAMIC METHOD 被引量:2
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作者 SHAO Jun Shanghai University of Science and Technology,Shanghai,ChinaXU Hua CHEN Nianyi Shanghai Institute of Metallurgy,Academia Sinica,Shanghai,China SHAO Jun Associate Professor,Dept.of Chemistry,Shanghai University of Science and Technology,Shanghai 201800,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1990年第10期221-225,共5页
The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusio... The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusion coeffients of Li^+,K^+,F^- and Cl^- have been calculated. The results are in agreement with the experimental values.The regularities of the distribution of ions and mieroscopic holes are discussed based on the results of computerized simulation. 展开更多
关键词 alkali halide molten salt molecular dynamic method computerized simulation
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A Modified Molecular Structural Mechanics Method for Analysis of Carbon Nanotubes 被引量:1
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作者 Ming-yuan Huang Hai-bo Chen +2 位作者 Ji-nan Lü Pin Lü Pei-qiang Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第4期286-290,共5页
A modified molecular structural mechanics method, based on molecular mechanics and similar to the finite element method, was developed. The energy of a system was expressed by the force field functions of the molecula... A modified molecular structural mechanics method, based on molecular mechanics and similar to the finite element method, was developed. The energy of a system was expressed by the force field functions of the molecular mechanics. Under the small deformation assumption and by the principle of minimum potential energy, the system function was established. The properties of tension and bending of single-walled carbon nanotubes were analyzed. The Young's modulus is about 0.36 TPa nm, which agrees perfectly with the results of previous analysis by other researchers. It is found, for the first time, that the Young's moduli, for Zigzag nanotubes, are different from each other when the system energy was expressed as the sum of two or three individual energy terms in molecular mechanics. Whereas, the Young's moduli were the same for the Armchair nanotubes. It is found, when simulating the bending, that the deflections are closer to the theoretical ones, of the classical elasticity, when the diameter of the carbon nanotube increases. 展开更多
关键词 Carbon nanotube molecular mechanics molecular structural mechanics method
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Clinical Observation on Treatment of 78 Patients of B-Thalassemla with Bushen Ylsul (补肾益髓) Method and Study on Its Molecular Mechanism 被引量:6
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作者 吴志奎 蔡辉国 +7 位作者 方素萍 张新华 王蕾 陈玉英 吕鑫霞 黄有文 王荣新 陈佩珍 《Chinese Journal of Integrated Traditional and Western Medicine》 2003年第2期141-141,共1页
Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with ... Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with BSYS recipe (consisted of 11 Chinese herbal drugs as Dogwood fruit, Fleeceflower root, prepared Rehmannia root and turtle shell, etc.) orally taken, 3 times per day, 10 g/time, 3 months as one therapeutic course. Hemoglobin (Hb), red blood cell (RBC), reticulocyte (Ret) and hemoglobin F (HbF) were checked every month. At the same time, PAGE, PVR, PCR-SSCP, RT-PCR, DNA series analysis, mRNA gene expression analysis techniques were used to conduct the systematic gene analysis in patients to study the molecular mechanism of TCM treatment from aspects of gene mutation, gene expression and control-regulation. Results: All the blood criteria in patients after BSYS treatment were improved significantly with clinical symptoms 展开更多
关键词 of in gene method and Study on Its molecular Mechanism Clinical Observation on Treatment of 78 Patients of B-Thalassemla with Bushen Ylsul HbF on with
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An efficient method for mapping the 12C+12C molecular resonances at low energies 被引量:1
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作者 Xiao-Dong Tang Shao-Bo Ma +4 位作者 Xiao Fang Brian Bucher Adam Alongi Craig Cahillane Wan-Peng Tan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第8期77-83,共7页
The 12C+12C fusion reaction is famous because of its complication of molecular resonances,and it plays an important role in both nuclear structural research and astrophysics. It is extremely difficult to measure the c... The 12C+12C fusion reaction is famous because of its complication of molecular resonances,and it plays an important role in both nuclear structural research and astrophysics. It is extremely difficult to measure the cross sections of 12C+12C fusions at energies of astrophysical relevance because of the very low reaction yields. To measure the complicated resonant structure that exists in this important reaction, an efficient thick target method has been developed and applied for the first time at energies Ec.m.<5.3 MeV. A scan of the cross sections over a relatively wide range of energies can be carried out using only a single beam energy. The result of measurement at Ec.m.=4.1 MeV is compared with results from previous work.This method will be useful for searching for potentially existing resonances of 12C+12C in the energy range 1 MeV<Ec.m.<3 MeV. 展开更多
关键词 12C+12C molecular RESONANCE THICK targetmethod 12C(12C p)^23Na
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The LBFGS quasi-Newtonian method for molecular modeling prion AGAAAAGA amyloid fibrils 被引量:1
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作者 Jiapu Zhang Yating Hou +2 位作者 Yiju Wang Changyu Wang Xiangsun Zhang 《Natural Science》 2012年第12期1097-1108,共12页
Experimental X-ray crystallography, NMR (Nuclear Magnetic Resonance) spectroscopy, dual polarization interferometry, etc. are indeed very powerful tools to determine the 3-Dimensional structure of a protein (including... Experimental X-ray crystallography, NMR (Nuclear Magnetic Resonance) spectroscopy, dual polarization interferometry, etc. are indeed very powerful tools to determine the 3-Dimensional structure of a protein (including the membrane protein);theoretical mathematical and physical computational approaches can also allow us to obtain a description of the protein 3D structure at a submicroscopic level for some unstable, noncrystalline and insoluble proteins. X-ray crystallography finds the X-ray final structure of a protein, which usually need refinements using theoretical protocols in order to produce a better structure. This means theoretical methods are also important in determinations of protein structures. Optimization is always needed in the computer-aided drug design, structure-based drug design, molecular dynamics, and quantum and molecular mechanics. This paper introduces some optimization algorithms used in these research fields and presents a new theoretical computational method—an improved LBFGS Quasi-Newtonian mathematical optimization method—to produce 3D structures of prion AGAAAAGA amyloid fibrils (which are unstable, noncrystalline and insoluble), from the potential energy minimization point of view. Because the NMR or X-ray structure of the hydrophobic region AGAAAAGA of prion proteins has not yet been determined, the model constructed by this paper can be used as a reference for experimental studies on this region, and may be useful in furthering the goals of medicinal chemistry in this field. 展开更多
关键词 Protein 3D Structure COMPUTATIONAL Approaches Optimization method molecular Modelling PRION AGAAAAGA AMYLOID FIBRILS
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Evaluation of Quantum Chemical Methods and Basis Sets Applied in the Molecular Modeling of Artemisinin
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作者 Cleydson B. R. dos Santos Cleison C. Lobato +5 位作者 Josinete B. Vieira Davi S. B. Brasil Alaan U. Brito Williams J. C. Macêdo José Carlos T. Carvalho José C. Pinheiro 《Computational Molecular Bioscience》 2013年第3期66-79,共14页
In this paper, we evaluate semiempirical methods (AM1, PM3, and ZINDO), HF and DFT (B3LYP) in different basis sets to determine which method best describes the sign and magnitude of the geometrical parameters of artem... In this paper, we evaluate semiempirical methods (AM1, PM3, and ZINDO), HF and DFT (B3LYP) in different basis sets to determine which method best describes the sign and magnitude of the geometrical parameters of artemisinin in the region of the endoperoxide ring compared to crystallographic data. We also classify these methods using statistical analysis. The results of PCA were based on three main components, explaining 98.0539% of the total variance, for the geometrical parameters C3O13, O1O2C3, O13C12C12a, and O2C3O13C12. The DFT method (B3LYP) corresponded well with the experimental data in the hierarchical cluster analysis (HCA). The experimental and theoretical angles were analyzed by simple linear regression, and statistical parameters (correlation coefficients, significance, and predictability) were evaluated to determine the accuracy of the calculations. The statistical analysis exhibited a good correlation and high predictive power for the DFT (B3LYP) method in the 6-31G** basis set. 展开更多
关键词 ARTEMISININ molecular Modeling QUANTUM CHEMICAL methods STATISTICAL Analysis B3LYP/6-31G**
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GALERKIN METHOD FOR COMPLETELY COMPRESSIBLE DISPLACEMENT WITH MOLECULAR DIFFUSION AND DISPERSION
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作者 CHENG AIJIE 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第1期59-67,共9页
In this paper, the numerical approximation by Galerkin method for completely compressible miscible displacement with molecular diffusion and dispersion in porous media is considered. Continuous time procedure is intro... In this paper, the numerical approximation by Galerkin method for completely compressible miscible displacement with molecular diffusion and dispersion in porous media is considered. Continuous time procedure is introduced and analysed. Some new techniques are applied to the analysis. Optimal error estimates in L ∞(J;H 1(Ω)) are proved, which implies an essential improvement to existed results. MR Subject Classification: 65N15,65N30. 展开更多
关键词 Compressible displacement molecular dispersion Galerkin method.
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血清HBV RNA分子特征、检测方法及临床应用研究
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作者 刘小花 余杨 +3 位作者 王桂香 张林艳 陈涛(综述) 黄华翠(审校) 《国际检验医学杂志》 CAS 2024年第22期2805-2808,2816,共5页
肝细胞内共价环状闭合DNA(cccDNA)是乙型肝炎病毒(HBV)的复制中间体,与HBV复制密切相关。同时,它是前基因组RNA(pgRNA)的转录模板,而血清中的HBV RNA多来自未逆转录的pgRNA。近年来许多研究表明HBV RNA在监测疾病进展和预测慢性HBV感染... 肝细胞内共价环状闭合DNA(cccDNA)是乙型肝炎病毒(HBV)的复制中间体,与HBV复制密切相关。同时,它是前基因组RNA(pgRNA)的转录模板,而血清中的HBV RNA多来自未逆转录的pgRNA。近年来许多研究表明HBV RNA在监测疾病进展和预测慢性HBV感染患者的预后等方面有重要作用,是慢性乙型病毒性肝炎的一种潜在的生物标志物。该文从HBV RNA的分子特征、检测方法及临床应用研究进展进行概述。 展开更多
关键词 乙型肝炎病毒 乙型肝炎病毒RNA 分子特征 检测方法 临床应用
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单酶法合成低分子量右旋糖酐的研究进展
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作者 秦艳 冼亮 +4 位作者 郑元涛 吴晶桃 李亿 梁戈 王青艳 《广西科学院学报》 2024年第2期181-188,共8页
低分子量右旋糖酐(Dextran)是以蔗糖为底物,由右旋糖酐蔗糖酶(Dextransucrase, DSR)催化合成葡萄糖聚合物后,再经酸水解/酶水解形成的化合物,其分子量为10 000-20 000 Da,可广泛应用于医药、食品等行业。本文综述了单酶法合成右旋糖酐... 低分子量右旋糖酐(Dextran)是以蔗糖为底物,由右旋糖酐蔗糖酶(Dextransucrase, DSR)催化合成葡萄糖聚合物后,再经酸水解/酶水解形成的化合物,其分子量为10 000-20 000 Da,可广泛应用于医药、食品等行业。本文综述了单酶法合成右旋糖酐的研究进展,包括微生物法/酶法生产右旋糖酐的优缺点,DSR的高效表达,单酶法合成右旋糖酐的过程调控,DSR的固定化技术、结构和催化机理,以及单酶法合成低分子量右旋糖酐的研究现状,并在此基础上提出DSR单酶一步法直接合成低分子量右旋糖酐的思路。借助人工智能技术可获得更详细的DSR结构信息,在进一步解析DSR的结构、功能和催化机理的基础上,对其进行合理的设计和改进,优化酶学性质,实现单酶一步法直接合成低分子量右旋糖酐,可为生产低分子量右旋糖酐提供了新的理论支持。 展开更多
关键词 单酶法 右旋糖酐蔗糖酶 低分子量右旋糖酐 一步法
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人工智能辅助的苏格拉底式对话教学在医学分子生物学中的实践
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作者 张静 王雅梅 孔璐 《基础医学教育》 2024年第7期614-618,共5页
文章探讨了在医学分子生物学教学中应用基于人工智能工具的苏格拉底式对话教学法的创新模式。通过结合苏格拉底式对话教学法和医学分子生物学教学的特点和挑战以及人工智能工具在促进教学效果和学习体验方面的关键作用,提出了针对大班... 文章探讨了在医学分子生物学教学中应用基于人工智能工具的苏格拉底式对话教学法的创新模式。通过结合苏格拉底式对话教学法和医学分子生物学教学的特点和挑战以及人工智能工具在促进教学效果和学习体验方面的关键作用,提出了针对大班额实施苏格拉底式对话教学法的挑战和对策,并进行了实践验证。研究结果表明,基于人工智能工具的苏格拉底式对话教学法能够提高学生的参与度和学习动力,促进批判性思维能力的培养,并实现个性化和差异化教学。这一创新模式将为医学分子生物学教学提供有效的教学方法和策略,推动医学教育的发展和进步。 展开更多
关键词 医学分子生物学 苏格拉底式对话教学法 人工智能 教学改革 大班教学
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利用网络药理学和分子对接法探讨痔宁浓煎剂治疗痔病的作用机制
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作者 王雪 候福红 张虹玺 《中医临床研究》 2024年第11期25-31,共7页
目的:利用网络药理学和分子对接法探讨痔宁浓煎剂治疗痔病的潜在作用机制。方法:应用中药系统药理学数据库与分析平台(TCMSP)收集痔宁浓煎剂中各药物的有效成分及其作用靶点,并通过UniProt数据库校正蛋白名称。通过GeneCards、OMIM、TTD... 目的:利用网络药理学和分子对接法探讨痔宁浓煎剂治疗痔病的潜在作用机制。方法:应用中药系统药理学数据库与分析平台(TCMSP)收集痔宁浓煎剂中各药物的有效成分及其作用靶点,并通过UniProt数据库校正蛋白名称。通过GeneCards、OMIM、TTD、DrugBank数据库获取痔病相关靶点,取药物靶点与疾病靶点交集后得到共有靶点。利用STRING数据库对共有靶点进行蛋白质-蛋白质相互作用网络分析,并通过Cytoscape 3.8.0软件进行拓扑特征分析,得到核心靶点。通过Metascape数据库对共有靶点进行基因本体论(GO)富集分析及京都基因与基因组百科全书(KEGG)通路富集分析。最后通过CB-Dock平台对药物的核心成分与核心靶点进行分子对接验证。结果:筛选全方共得到184个药物有效成分、544个药物靶点,获取疾病靶点663个,药物与疾病共有靶点有80个,通过蛋白质-蛋白质相互作用网络拓扑特征分析得到细胞肿瘤抗原p53(Tumor Protein p53,TP53)、白细胞介素(Interleukin,IL)-6、雌激素受体1(Estrogen Receptor 1,ESR1)、MYC原癌基因(MYC Proto-Oncogene,MYC)、肿瘤坏死因子(Tumor Necrosis Factor,TNF)等10个核心靶点。GO及KEGG富集分析显示痔宁浓煎剂治疗痔病可能与磷脂酰肌醇3激酶(Phosphatidylinositol 3-kinase,PI3K)-蛋白激酶B(Akt)信号通路、丝裂原活化蛋白激酶(Mitogen-Activated Protein Kinase,MAPK)信号通路、卡波西肉瘤相关性疱疹病毒感染等通路相关。分子对接结果显示槲皮素、豆甾醇、β-谷甾醇与痔病的IL-6、TNF、TP53等靶点对接吻合度较好。结论:痔宁浓煎剂的槲皮素、豆甾醇、β-谷甾醇等核心成分可能通过调节TP53、MYC、TNF、IL-6等靶点作用于MAPK、PI3K-Akt等信号通路来治疗痔病。 展开更多
关键词 痔病 痔宁浓煎剂 网络药理学 分子对接法 作用机制
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黏度法测聚合物分子量实验的一些细节问题
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作者 袁俊杰 袁华 《当代化工》 CAS 2024年第10期2505-2510,共6页
黏度法测聚合物分子量是高分子物理中一个经典实验教学内容,也是科学研究中常用的测量分子量方法。针对黏度法测定聚合物分子量过程常遇到的3个细节问题给出相应的经验及建议:用超声波法消除乌氏黏度计测量时聚合物水溶液出现的气泡是... 黏度法测聚合物分子量是高分子物理中一个经典实验教学内容,也是科学研究中常用的测量分子量方法。针对黏度法测定聚合物分子量过程常遇到的3个细节问题给出相应的经验及建议:用超声波法消除乌氏黏度计测量时聚合物水溶液出现的气泡是一种高效方法;对于同一聚合物来讲,除了温度和溶剂对Κ和α值有决定性影响外,分子量范围也是一个不容忽视的条件,研究者应在确定所测聚合物大致分子量范围之后,首先查阅高分子手册等参考资料来确定合适的测试条件及相应的Κ和α值;通过实验发现,采用乌氏黏度计法测定聚合物分子量,聚合物稀溶液存在一个最佳质量浓度范围,只有在这个范围内测定数据,最后计算得到的分子量才比较准确。 展开更多
关键词 黏度法 分子量 超声波法 Κ和α值 稀溶液质量浓度
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GALERKIN METHOD FOR COMPRESSIBLE FLOW OF CONTAMINATION FROM NUCLEAR WASTE WITH MOLECULAR DIFFUSION AND DISPERSION
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作者 程爱杰 王高洪 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1999年第1期39-52,共14页
Abstract A system of quasilinear coupled equations which arise from simulation of contamination of geologic nulear waste in porous media is studied. We’ll discuss Galerkin method for the model of compressible flow wi... Abstract A system of quasilinear coupled equations which arise from simulation of contamination of geologic nulear waste in porous media is studied. We’ll discuss Galerkin method for the model of compressible flow with molecular diffusion and dispersion. Some new techniques are introcued to error analysis. Only one dimensional case is considered. The optimal error estimate in both L^2 and H^1 is proved. A contribution of this paper is how the dispersion term can be handled, 展开更多
关键词 COMPRESSIBLE flow CONTAMINATION of nuclear waste molecular diffusion and DISPERSION GALERKIN finite element method optimal error estimate.
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聚噻吩衍生物/银纳米线结合分子印迹法检测葡萄糖
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作者 刘洋 李丽娟 +3 位作者 陈志冉 白婷芳 乌兰格日乐 海文峰 《内蒙古民族大学学报(自然科学版)》 2024年第5期27-33,共7页
通过在银纳米线上沉积3氟苯硼酸接枝的3,4-乙烯二氧噻吩(EDOT-FPBA)和葡萄糖,制备了一种基于表面分子印迹(MIP)法的葡萄糖生物传感器。在玻碳电极(GCE)表面依次沉积银纳米线(AgNWs)、EDOT-FPBA和葡萄糖,然后洗脱葡萄糖模板后得到分子印... 通过在银纳米线上沉积3氟苯硼酸接枝的3,4-乙烯二氧噻吩(EDOT-FPBA)和葡萄糖,制备了一种基于表面分子印迹(MIP)法的葡萄糖生物传感器。在玻碳电极(GCE)表面依次沉积银纳米线(AgNWs)、EDOT-FPBA和葡萄糖,然后洗脱葡萄糖模板后得到分子印迹葡萄糖生物传感器。采用电化学阻抗法检测葡萄糖,在0.05~20.00 mmol/L范围内,葡萄糖浓度与电荷转移电阻呈线性关系,检测限低至0.03 mmol/L(R2=0.9905)。此外,该传感器具有良好的特异性、稳定性、可重复使用性和存储稳定性,并且可在生理pH下对葡萄糖进行灵敏检测。 展开更多
关键词 分子印迹法 葡萄糖检测 电化学 生物传感器 银纳米线
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鹿茸标准鉴别技术进展研究
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作者 李雪莹 《中国标准化》 2024年第2期159-163,共5页
鹿茸是一种具有重要药用价值的中药材,具有多种功效和广泛的临床应用。然而,由于市场上出现了大量的假冒伪劣产品,对鹿茸的鉴别技术的研究变得十分重要。本文综述了近年来鹿茸的鉴别技术进展,包括传统的鉴别方法以及现代分子生物学和化... 鹿茸是一种具有重要药用价值的中药材,具有多种功效和广泛的临床应用。然而,由于市场上出现了大量的假冒伪劣产品,对鹿茸的鉴别技术的研究变得十分重要。本文综述了近年来鹿茸的鉴别技术进展,包括传统的鉴别方法以及现代分子生物学和化学分析技术等。同时,还对当前鹿茸鉴别技术的挑战和未来发展方向进行了讨论。 展开更多
关键词 鹿茸 鉴别技术 传统方法 分子生物学 化学分析
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MRI特征辅助分类乳腺癌分子亚型的临床研究
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作者 郭峰 侯信明 +2 位作者 王春锋 张海芹 宋张骏 《中国CT和MRI杂志》 2024年第6期100-103,共4页
目的 应用磁共振(MRI)图像中提取的特征和机器学习方法来帮助区分乳腺癌分子亚型,以期为临床诊治提供参考。方法 回顾性分析我院于2021年10月-2023年10月间确诊的178例乳腺癌患者的临床资料,每个患者肿瘤的形状、MRI特征和基于直方图的... 目的 应用磁共振(MRI)图像中提取的特征和机器学习方法来帮助区分乳腺癌分子亚型,以期为临床诊治提供参考。方法 回顾性分析我院于2021年10月-2023年10月间确诊的178例乳腺癌患者的临床资料,每个患者肿瘤的形状、MRI特征和基于直方图的特征是使用内部软件从增强前和三次增强后的MRI图像上提取的。同时收集临床和病理资料。基于机器学习模型识别重要的成像特征并建立预测IDC亚型的模型。采用留一法交叉验证(LOOCV)避免模型过度拟合,采用Kruskal-Wallis检验确定统计学意义。结果 LOOCV过程生成一个具有不同特征的模型,在排名前20位的特征中,有11项在IDC亚型之间存在显著差异(P<0.05)。综合前九种病理和影像特征,预测模型对IDC亚型的识别准确率为83,4%。病理和影像联合模型对各亚型的准确率分别为89.2%(ERPR1)、63.6%(ERPR-/HER21)和8 2.5%(TN)。当仅结合前9个成像特征时,预测模型在LOOCV上识别IDC亚型的总体准确率为71.2%。病理和影像联合模型对各亚型的准确率分别为69.9%(ERPR1)、62.9%(ERPR-/HER21)和81.0%(TN)。结论 我们开发了一个基于机器学习的预测模型,该模型使用从M RI提取的特征来区分具有显著预测能力的IDC亚型。 展开更多
关键词 磁共振 乳腺癌分子亚型 留一法交叉验证
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Molecular detection of Helicobacter pylori antibiotic resistance in stool vs biopsy samples 被引量:7
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作者 Denise E Brennan Joseph Omorogbe +5 位作者 Mary Hussey Donal Tighe Grainne Holleran Colm O'Morain Sinéad M Smith Deirdre McNamara 《World Journal of Gastroenterology》 SCIE CAS 2016年第41期9214-9221,共8页
AIM To compare(1) demographics in urea breath test(UBT) vs endoscopy patients; and(2) the molecular detection of antibiotic resistance in stool vs biopsy samples.METHODS Six hundred and sixteen adult patients undergoi... AIM To compare(1) demographics in urea breath test(UBT) vs endoscopy patients; and(2) the molecular detection of antibiotic resistance in stool vs biopsy samples.METHODS Six hundred and sixteen adult patients undergoing endoscopy or a UBT were prospectively recruited to the study. The Geno Type Helico DR assay was used to detect Helicobacter pylori(H. pylori) and antibiotic resistance using biopsy and/or stool samples from CLOpositive endoscopy patients and stool samples from UBT-positive patients. RESULTS Infection rates were significantly higher in patients referred for a UBT than endoscopy(overall rates: 33% vs 19%; treatment-na?ve patients: 33% vs 14.7%, respectively). H. pylori-infected UBT patients were younger than H. pylori-infected endoscopy patients(41.4 vs 48.4 years, respectively, P < 0.005), with a higher percentage of H. pylori-infected males in the endoscopy-compared to the UBT-cohort(52.6% vs 33.3%, P = 0.03). The Geno Type Helico DR assay was more accurate at detecting H. pylori infection using biopsy samples than stool samples [98.2%(n = 54/55) vs 80.3%(n =53/66), P < 0.005]. Subset analysis using stool and biopsy samples from CLO-positive endoscopy patients revealed a higher detection rate ofresistance-associated mutations using stool samples compared to biopsies. The concordance rates between stool and biopsy samples for the detection of H. pylori DNA, clarithromycin and fluoroquinolone resistance were just 85%, 53% and 35%, respectively. CONCLUSION Differences between endoscopy and UBT patients provide a rationale for non-invasive detection of H. pylori antibiotic resistance. However, the Geno Type Helico DR assay is an unsuitable approach. 展开更多
关键词 Helicobacter pylori Antibiotic resistance CLARITHROMYCIN FLUOROQUINOLONE molecular methods
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难浮煤−极性捕收剂相互作用研究新视角:分子对接与诱导契合效应 被引量:1
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作者 蘧鹏程 夏阳超 +3 位作者 薛志刚 邢耀文 桂夏辉 田佳 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第3期283-290,共8页
研究煤泥与浮选药剂间的相互作用将是浮选过程强化的热点和难点,针对难浮煤表面强亲水的化学结构特性,将生物医药领域诱导契合效应引入到难浮煤−极性捕收剂的相互作用研究中。基于煤样性质检测结果,构建了3D煤分子结构,采用原型分子(Pro... 研究煤泥与浮选药剂间的相互作用将是浮选过程强化的热点和难点,针对难浮煤表面强亲水的化学结构特性,将生物医药领域诱导契合效应引入到难浮煤−极性捕收剂的相互作用研究中。基于煤样性质检测结果,构建了3D煤分子结构,采用原型分子(Protomol)技术搜索并表示煤分子活性口袋,在活性口袋中搜索极性捕收剂与难浮煤的分子对接最优构象,根据极性药剂与煤分子相互作用最优构象的结合能大小,分析分子对接和诱导契合效应研究结果与浮选结果之间的对应性关系。结果表明分子对接结果与难浮煤可燃体回收率均呈现出十二醇<十二醛<十二酸甲酯的规律,浮选可燃体回收率与分子对接结合能绝对值、煤分子诱导契合效应呈现明显的正相关关系,揭示了分子对接对浮选药剂筛选的指导作用。根据分子对接构型可知结合能存在差异性归因于π-CH作用和空间位阻作用的不同。进而将药剂分子的三维空间进行固定,采用分子力学模拟对三种极型捕收剂与煤分子间“诱导契合效应”进行探索,发现十二酸甲酯与煤分子活性区域能够产生更大的相互作用,煤分子活性区域对十二酸甲酯的诱导效应、包裹性更强,因而在浮选过程中效果更好。采用分子对接和诱导契合效应研究煤分子与药剂相互作用,可为浮选捕收剂的快速筛选提供技术途径和科学指导。 展开更多
关键词 难浮煤 极性捕收剂 分子对接 对接打分方法 诱导契合
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