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Novel frameshift mutation causes early termination of the thyroxine-binding globulin protein and complete thyroxine-binding globulin deficiency in a Chinese family: A case report 被引量:1
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作者 Ping-Ping Dang Wei-Wei Xiao +5 位作者 Zhong-Yan Shan Yue Xi Ran-Ran Wang Xiao-Hui Yu Wei-Ping Teng Xiao-Chun Teng 《World Journal of Clinical Cases》 SCIE 2019年第22期3887-3894,共8页
BACKGROUND Thyroxine-binding globulin(TBG;the gene product of SERPINA7)is the main transporter of thyroid hormones in humans.Mutations in the TBG gene may lead to inherited TBG deficiency.There have been 28 reported m... BACKGROUND Thyroxine-binding globulin(TBG;the gene product of SERPINA7)is the main transporter of thyroid hormones in humans.Mutations in the TBG gene may lead to inherited TBG deficiency.There have been 28 reported mutations that associate with complete TBG deficiency(TBG-CD).Here we identified a novel frameshift mutation causing early termination of the TBG protein and TBG-CD in a Chinese family.CASE SUMMARY A 46-year-old Chinese man was referred to our hospital with normal free thyroxine,free triiodothyronine,thyrotropin,but lower total thyroxine and total triiodothyronine,and undetectable serum TBG,indicative of TBG-CD.Blood samples were obtained from the patient’s family members and thyroid function and serum TBG were evaluated.Genomic DNA from peripheral blood was sequenced to detect possible TBG mutation(s).Quantitative PCR high-resolution melting curve analysis was used to screen TBG-Poly(L283F)among 117 Chinese men.A novel mutation of TBG(p.Phe135Alafs*21),a 19-nucleotide insertion in exon 1,was identified,which resulted in a truncated TBG protein product and caused TBG-CD.The other mutation,identified in the proband’s father,is a known polymorphism,TBG-Poly(L283F).The frequency of the TBG-Poly allele among 117 unrelated Han Chinese men from northeast China was 21.37%.CONCLUSION A novel mutation in the TBG gene associated with the TBG-CD phenotype was identified in a Chinese family.Additionally,it was found that 21.37%of Chinese males had TBG-Poly(L283F). 展开更多
关键词 Thyroxine-binding GLOBULIN COMPLETE thyroxine-binding GLOBULIN DEFICIENCY Partial thyroxine-binding GLOBULIN DEFICIENCY Gene polymorphism Case report
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Principle of Scalar Electrodynamics Phenomena Proof and Theoretical Research 被引量:2
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作者 Bahman Zohuri 《Journal of Energy and Power Engineering》 2018年第8期408-417,共10页
There exist a lot of controversial issues around the subject of SW(Scalar Waves)and the purpose of this white paper is to take an innovative theoretical approach to prove and backup up existence of such phenomena.We b... There exist a lot of controversial issues around the subject of SW(Scalar Waves)and the purpose of this white paper is to take an innovative theoretical approach to prove and backup up existence of such phenomena.We basically define this wave as a SLW(Scalar Longitudinal Wave),whose existence derives from the MCE(More Complete Electrodynamic)theory aspect of Maxwell’s classical electrodynamic equations.MCE falls into the QED(Quantum Electrodynamic)aspect of the Maxwell’s equations,in particular out of his four famous classical equations,our interest focuses on the one that is known to us as Faraday’s Law of the Maxwell’s Equation set. 展开更多
关键词 SCALAR WAVE more complete Maxwell’s equation longitudinal WAVE quantum electrodynamic LAGRANGIAN and HAMILTONIAN relationship
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Some substrates of P-glycoprotein targeting <i>β</i>-amyloid clearance by quantitative structure-activity relationship (QSAR)/membrane-interaction (MI)-QSAR analysis
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作者 Tongyang Zhu Jie Chen Jie Yang 《Advances in Bioscience and Biotechnology》 2013年第9期872-895,共24页
The pathogenesis of Alzheimer’s disease (AD) putatively involves a compromised blood-brain barrier (BBB). In particular, the importance of brain-to-blood transport of brain-derived metabolites across the BBB has gain... The pathogenesis of Alzheimer’s disease (AD) putatively involves a compromised blood-brain barrier (BBB). In particular, the importance of brain-to-blood transport of brain-derived metabolites across the BBB has gained increasing attention as a potential mechanism in the pathogenesis of neurodegenerative disorders such as AD, which is characterized by the aberrant polymerization and accumulation of specific misfolded proteins, particularly β-amyloid (Aβ), a neuropathological hallmark of AD. P-glycoprotein (P-gp), a major component of the BBB, plays a role in the etiology of AD through Aβ clearance from the brain. Our QSAR models on a series of purine-type and propafenone-type substrates of P-gp showed that the interaction between P-gp and its modulators depended on Molar Refractivity, LogP, and Shape Attribute of drugs it transports. Meanwhile, another model on BBB partitioning of some compounds revealed that BBB partitioning relied upon the polar surface area, LogP, Balaban Index, the strength of a molecule combined with the membrane-water complex, and the changeability of the structure of a solute-membrane-water complex. The predictive model on BBB partitioning contributes to the discovery of some molecules through BBB as potential AD therapeutic drugs. Moreover, the interaction model of P-gp and modulators for treatment of multidrug resistance (MDR) indicates the discovery of some molecules to increase Aβ clearance from the brain and reduce Aβ brain accumulation by regulating BBB P-gp in the early stages of AD. The mechanism provides a new insight into the therapeutic strategy for AD. 展开更多
关键词 P-Glycoproteins Quantitative STRUCTURE-ACTIVITY relationship ATP-bindING Cassette Transporters MULTIDRUG Resistance Blood-Brain Barrier
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Structure-activity relationship of endomorphins and their analogs
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作者 HUO Xiaofeng WU Ming +2 位作者 REN Weihua WANG Rui CHAN Albert S.C. 《Chinese Science Bulletin》 SCIE EI CAS 2001年第13期1096-1100,共5页
To study the structure-activity relationship of endomorphins (EMs), the action of opioid receptor binding (AORB), analgesic activity and vasodilator effects of EMs and their eight analogs were investigated, which were... To study the structure-activity relationship of endomorphins (EMs), the action of opioid receptor binding (AORB), analgesic activity and vasodilator effects of EMs and their eight analogs were investigated, which were prepared by rationally replacing the 2-/3-amino acid (Aa) of EMs. The results showed: (i) The 2-Aa was comparatively more related to the selectivity of EMs while the 3-Aa to their affinity; (ii) the analgesia and vasodilatation of EMs and their analogs were not completely dictated by their AORB (in vitro), the action of [D-Pro2]EM-2 was unusual; (iii) EMs lost their analgesia in the central nervous system and their vasodilatation in the circulatory system with different mechanisms; the former was due to the degradation of some peptidase, and the latter possibly due to the feedback inhibition. 展开更多
关键词 ENDOMORPHINS STRUCTURE-ACTIVITY relationship action of OPIOID receptor binding ANALGESIA VASODILATATION mechanism of inactivation.
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A uniform catalog of earthquakes for seismic hazard asesment in Iran
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作者 高孟谭 陈运泰 王健 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第6期20-33,共14页
The assessment of seismicity is strongly dependent on the recorded events as data base. A uniform catalog of earthquakes in Iran and neighbouring regions is provided to use for seismic hazard assessment of the countr... The assessment of seismicity is strongly dependent on the recorded events as data base. A uniform catalog of earthquakes in Iran and neighbouring regions is provided to use for seismic hazard assessment of the country. Since the recurrence time of maximum credible earthquake can not be estimated directly from m b, empirical relationships for different seismotectonic provinces are established to convert m b to M S , which is a suitable magnitude scale for our purpose. It emerges from completeness study of the catalog that many small and moderate earthquakes are missed out, specially in the historical and early instrumental time periods. 展开更多
关键词 SEISMICITY uniform catalog seismic hazard empirical relationships completeness
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Influences of the Hydrophobicity of the Heme-binding Pocket on the Properties and Functions of Cytochrome b_5 Mutants
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作者 甘建华 王韵华 +2 位作者 邬键 黄仲贤 夏宗芗 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2003年第10期1385-1389,共5页
The mutation sites of the four mutants F35Y, P40V, V45E and V45Y of cytochrome b 5 are located at the edge of the heme binding pocket. The solvent accessible areas of the “pocket interior” of the four mutants ... The mutation sites of the four mutants F35Y, P40V, V45E and V45Y of cytochrome b 5 are located at the edge of the heme binding pocket. The solvent accessible areas of the “pocket interior” of the four mutants and the wild type cytochrome b 5 have been calculated based on their crystal structures at high resolution. The change in the hydrophobicity of the heme binding pocket resulting from the mutation can be quantitatively described using the difference of the solvent accessible area of the “pocket interior” of each mutant from that of the wild type cytochrome b 5. The influences of the hydrophobicity of the heme binding pocket on the protein stability and redox potential are discussed. 展开更多
关键词 cytochrome b 5 MUTANT heme binding pocket solvent accessible area hydrophobicity structure function relationship
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SARs Investigation of α-, β-, γ-, δ-, ε-RuCl2(Azpy)2 Complexes as Antitumor Drugs 被引量:2
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作者 Kafoumba Bamba Ouattara Wawohinlin Patrice +1 位作者 N’Guessan Kouakou Nobel Nahossé Ziao 《Computational Chemistry》 2016年第1期1-10,共10页
Structure Activity-Relationships (SARs) of the five possible isomers of RuCl<sub>2</sub>(Azpy)<sub>2</sub> were predicted thanks to DFT method. Azpy stands for 2-phenylazopyridine and the struc... Structure Activity-Relationships (SARs) of the five possible isomers of RuCl<sub>2</sub>(Azpy)<sub>2</sub> were predicted thanks to DFT method. Azpy stands for 2-phenylazopyridine and the structure of the isomers α-RuCl<sub>2</sub>(Azpy)<sub>2</sub>, β-RuCl<sub>2</sub>(Azpy)<sub>2</sub>, γ-RuCl2(Azpy)2, δ-RuCl<sub>2</sub>(Azpy)<sub>2</sub> and ε-RuCl<sub>2</sub>(Azpy)<sub>2</sub> call respectively α-Cl, β-Cl, γ-Cl, δ-Cl and ε-Cl are defined according to chlorine atoms orientations. Hence, they are divided into two groups. In the first group comprising α-Cl, β-Cl and ε-Cl, both chlorine atoms are in cis position and Azpy ligands are intervertical. Whereas the two others isomers (γ-Cl and δ-Cl), they form the second group. Here, both chlorine are in trans position and Azpy are planar. The five synthesized isomers were investigated as potential antitumor agents. Then, regarding the DNA, its bases are stacked by pair. Therefore, complexes are assumed to insert and to stack on them through intercalative mode. So the electronic and geometric structures become more important to describe their SARs. Consequently, group 2 regarding γ-Cl and δ-Cl presents the best structure to allow intercalation between DNA base-pairs. Besides, the energy order of the lower unoccupied molecular orbital (LUMO) of the isomers is ELUMO(β-Cl) > ELUMO(α-Cl) > ELUMO(ε-Cl) > ELUMO(γ-Cl) > ELUMO(δ-Cl). The energy gap between LUMO and HOMO was also sorted as Δ(L-H)(β-Cl) > Δ(L-H)(α-Cl) > Δ(L-H)(ε-Cl) > Δ(L-H)(γ-Cl) > Δ(L-H)(δ-Cl). In addition, the total dipole moment was classified as μ(ε-Cl) > μ(β-Cl) > μ(α-Cl) > μ(γ-Cl) > μ(δ-Cl). Finally, net charge of the ligand Azpy was also classified as QL(δ-Cl) > QL(γ-Cl) > QL(ε-Cl) > QL(α-Cl) > QL(β-Cl). All those parameters show that δ-Cl isomer displays the highest activity as antitumor drug when intercalating between the DNA basepairs Cytosine-Guanine/Cytosine-Guanine (CG/CG). 展开更多
关键词 Structure Activity-relationship (SARs) Ru (II) Complexes Azpy DFT Lanl2dz DNA-bindING
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分体式颌位关系记录托盘的设计与应用
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作者 潘景光 朱朋 +1 位作者 冯玥 冯志宏 《实用口腔医学杂志》 CAS CSCD 北大核心 2024年第3期443-448,共6页
现有的颌位关系记录托盘为上下一体式设计,在临床使用过程中无法准确获取上颌平面、上唇下约1 mm的位置、上唇支撑度等重要信息。从而使得数字化颌托(或诊断义齿)准确性欠佳,为后继进行准确边缘整塑印模及最终颌位关系记录与转移带来困... 现有的颌位关系记录托盘为上下一体式设计,在临床使用过程中无法准确获取上颌平面、上唇下约1 mm的位置、上唇支撑度等重要信息。从而使得数字化颌托(或诊断义齿)准确性欠佳,为后继进行准确边缘整塑印模及最终颌位关系记录与转移带来困难。该文介绍了一种分体式颌位关系记录托盘的设计、临床使用方法及要点。其能够准确获取上颌平面、上唇下约1 mm的位置、上唇支撑度等重要信息,为后继进行准确的颌位关系记录与转移提供参考,也为利用口内扫描获取数字化印模后,基于采用分体式颌位关系记录托盘获取的平面、上唇下约1 mm的位置、上唇支撑度等信息直接制作全口义齿奠定基础。 展开更多
关键词 全口义齿 数字化技术 颌位关系记录托盘 颌位关系 [牙合]平面
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完全图高阶关系驱动的链接预测 被引量:1
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作者 张惠鹃 黄钦阳 +2 位作者 胡诗彦 杨青 张敬伟 《计算机研究与发展》 EI CSCD 北大核心 2024年第7期1825-1835,共11页
图卷积网络(graph convolutional network,GCN)因其在处理图数据方面的独特优势而被广泛应用于推荐系统中,它通过利用图中节点之间的依赖关系传播节点属性信息,极大地提高了节点表示的准确度从而提升推荐性能.然而现有基于GCN的推荐方... 图卷积网络(graph convolutional network,GCN)因其在处理图数据方面的独特优势而被广泛应用于推荐系统中,它通过利用图中节点之间的依赖关系传播节点属性信息,极大地提高了节点表示的准确度从而提升推荐性能.然而现有基于GCN的推荐方法仍因过平滑问题而难以进行更深层的建模,从而限制了用户与项目间高阶关系的表达.为此,提出了一种基于项目间关系的完全图高阶关系驱动的链接预测(link prediction driven by high-order relations in complete graph,LinkCG)方法.LinkCG通过用户-项目交互图与项目间隐式关联关系全局图组成的异构图预测用户到项目的链接,跳过了中间的用户节点直接利用完全图建模每个用户历史交互的项目间的局部隐式关联关系,获得项目间的高阶关系从而缓解数据稀疏性问题;此外,不同于基于节点嵌入的推荐方法,LinkCG通过赋予项目间的链接权重来表示项目间关系的紧密程度,并根据紧密程度进行链接预测,优化了模型的训练过程.在3个公开数据集上的实验结果表明,LinkCG作为只包含2个超参数的非深度学习模型,与一些先进的基于深度学习的基线方法相比提供了更好的性能.在社交关系数据上的应用进一步表明LinkCG能够从用户历史交互项目中获取足够丰富的用户偏好信息. 展开更多
关键词 推荐系统 链接预测 完全图 高阶关系 关联关系
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融合关系上下文与路径的茶叶种植知识图谱关系补全模型
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作者 单源源 李书琴 《农业工程学报》 EI CAS CSCD 北大核心 2024年第13期171-178,共8页
针对茶叶种植知识图谱不完备问题,该研究提出了一种融合关系上下文与路径的茶叶种植知识图谱关系补全模型。模型由TeaConAggr(tea context aggregate)聚合模块、多层关系消息传递机制、关系路径聚合模块和关系路径学习模块组成,首先利用... 针对茶叶种植知识图谱不完备问题,该研究提出了一种融合关系上下文与路径的茶叶种植知识图谱关系补全模型。模型由TeaConAggr(tea context aggregate)聚合模块、多层关系消息传递机制、关系路径聚合模块和关系路径学习模块组成,首先利用TeaConAggr模块对实体的各跳关系上下文进行聚合,通过多层关系消息传递机制将各跳关系上下文进行汇总,从而得到实体对的关系上下文;其次使用关系路径聚合模块对实体之间的关系路径进行聚合,并通过关系路径学习模块对路径进行学习;最后通过注意力机制对关系上下文和关系路径进行融合,以实现实体关系补全的目标。模型在自建的茶叶种植知识图谱数据集TPKGData上开展试验,试验结果表明:该模型在平均倒数排名、命中率Hits@1和命中率Hits@3三个指标上分别达到了85.40%、80.95%和90.08%,与Shallom模型相比分别提高了2.56%、2.63%和4.25%个百分点。此外,模型在公开数据集FB15K-237和WN18RR上与Shallom模型进行试验对比,平均倒数排名分别提高了2.17%和1.05个百分点,进一步表明本文模型具有较好的泛化能力。 展开更多
关键词 模型 知识图谱 茶叶种植 图谱补全 关系上下文 关系路径
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Molecular structure and phylogenetic analyses of the complete chloroplast genomes of three original species of Pyrrosiae Folium 被引量:2
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作者 YANG Chu-Hong LIU Xia +5 位作者 CUI Ying-Xian NIE Li-Ping LIN Yu-Lin WEI Xue-Ping WANG Yu YAO Hui 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2020年第8期573-581,共9页
Pyrrosia petiolosa,Pyrrosia lingua and Pyrrosia sheareri are recorded as original plants of Pyrrosiae Folium(PF)and commonly used as Chinese herbal medicines.Due to the similar morphological features of PF and its adu... Pyrrosia petiolosa,Pyrrosia lingua and Pyrrosia sheareri are recorded as original plants of Pyrrosiae Folium(PF)and commonly used as Chinese herbal medicines.Due to the similar morphological features of PF and its adulterants,common DNA barcodes cannot accurately distinguish PF species.Knowledge of the chloroplast(cp)genome is widely used in species identification,molecular marker and phylogenetic analyses.Herein,we determined the complete cp genomes of three original species of PF via highthroughput sequencing technologies.The three cp genomes exhibited a typical quadripartite structure with sizes ranging from 158165 to 163026 bp.The cp genomes of P.petiolosa and P.lingua encoded 130 genes,whilst that of P.sheareri encoded 131 genes.The complete cp genomes were compared,and five highly divergent regions of pet A-psb J,mat K-rps16,ndh C-trn M,psb M-pet N and psa Cndh E were screened as potential DNA barcodes for identification of Pyrrosia genus species.The phylogenetic tree we obtained indicated that P.petiolosa and P.lingua are clustered in a single clade and,thus,share a close relationship.This study provides invaluable information for further studies on the species identification,taxonomy and phylogeny of Pyrrosia genus species. 展开更多
关键词 Complete chloroplast genome Pyrrosia petiolosa Pyrrosia lingua Pyrrosia sheareri IDENTIFICATION Phylogenetic relationship
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Uncovering the dynamic evolution of nucleotidebinding site-leucine-rich repeat(NBS-LRR) genes in Brassicaceae 被引量:9
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作者 Yan-Mei Zhang Zhu-Qing Shao +4 位作者 Qiang Wang Yue-Yu Hang Jia-Yu Xue Bin Wang Jian-Qun Chen 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2016年第2期165-177,共13页
Plant genomes harbor dozens to hundreds of nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes; however, the long-term evolutionary history of these resistance genes has not been fully understood, This study... Plant genomes harbor dozens to hundreds of nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes; however, the long-term evolutionary history of these resistance genes has not been fully understood, This study focuses on five Brassicaceae genomes and the Carica papaya genome to explore changes in NBS-LRR genes that have taken place in this Rosid II lineage during the past 72 million years. Various numbers of NBS-LRR genes were identified from Arabidopsis lyrata (198), A. thaliana (165), Brassica rapa (204), Capsella rubella (127), Thellungiella salsuginea (88), and C. papaya (51). In each genome, the identified NBS-LRR genes were found to be unevenly distributed among chromosomes and most of them were clustered together. Phylogenetic analysis revealed that, before and after Brassicaceae speciation events, both toll/interleukin-1 receptor-NBS-LRR (TNL) genes and non-toll/interleukin-1 receptor-NBS-LRR (nTNL) genes exhibited a pattern of first expansion and then contraction, suggesting that both subclasses of NBS-LRR genes were responding to pathogen pressures synchronically. Further, by examining the gain/loss of TNL and nTNL genes at different evolutionary nodes, this study revealed that both events often occurred more drastically in TNL genes. Finally, the phylogeny of nTNL genes suggested that this NBS-LRR subclass is composed of two separate ancient gene types: RPW8-NBS-LRR and Coiled-coiI-N BS-LRR. 展开更多
关键词 Dynamic evolution nucleotide-binding site-leucine-rich repeat gene phylogenetic relationship plant disease resistance
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3种方法确定水平颌位关系的全口义齿咀嚼肌肌电活动及咀嚼效率分析 被引量:13
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作者 刘翠玲 杨丽媛 +1 位作者 郑政 高旭 《华西口腔医学杂志》 CAS CSCD 北大核心 2016年第5期493-497,共5页
目的通过肌电图及吸光光度法比较3种方法确定水平颌位关系的全口义齿的咬肌和颞肌前束的肌电活动以及义齿的咀嚼效率。方法对10例口颌系统基本正常的无牙颌患者在适宜的垂直距离条件下,同时制作由哥特式弓轨迹顶点、哥特式弓轨迹顶点前1... 目的通过肌电图及吸光光度法比较3种方法确定水平颌位关系的全口义齿的咬肌和颞肌前束的肌电活动以及义齿的咀嚼效率。方法对10例口颌系统基本正常的无牙颌患者在适宜的垂直距离条件下,同时制作由哥特式弓轨迹顶点、哥特式弓轨迹顶点前1 mm以及直接咬合法确定水平颌位关系的3副全口义齿,分别记作义齿A、B和C。用肌电诱发电位仪分别记录患者戴用3副义齿在正中大力咬合及咀嚼过程中的咬肌和颞肌前束肌电图,记录肌电幅值,计算左右两侧咬肌和颞肌前束的不对称指数;用吸光光度法评价3副义齿的咀嚼效率;通过SPSS 17.0软件对所得数据进行统计学分析。结果在正中大力咬合及咀嚼运动过程中,义齿B和义齿C的肌电幅值明显高于义齿A(P<0.05),义齿C的不对称指数最高,明显高于义齿A和B(P<0.05)。义齿B和C咀嚼效率的差异无统计学意义(P>0.05),均高于义齿A(P<0.05)。结论在哥特式弓轨迹顶点前1 mm处建立水平颌位关系的全口义齿的肌电活动更强且更加平衡,有利于咀嚼肌功能的发挥,咀嚼效率较高。 展开更多
关键词 全口义齿 上下颌水平颌位关系记录 肌电图 咀嚼效率
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一种新的基于全口义齿测量的牙列缺失修复用颌位记录托盘 被引量:4
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作者 刘洋 胡菳洳 +4 位作者 赵一姣 王勇 孙玉春 潘韶霞 冯海兰 《北京大学学报(医学版)》 CAS CSCD 北大核心 2020年第2期368-372,共5页
目的:测量全口义齿的相关特征数据,并以此设计用于牙列缺失患者全口义齿修复的一种新的、可记录各种参数的颌位记录托盘。方法:对100副在临床应用的全口义齿,测量双侧上颌第一磨牙中央窝间距a1、上颌第一磨牙中央窝连线至义齿前缘距离a... 目的:测量全口义齿的相关特征数据,并以此设计用于牙列缺失患者全口义齿修复的一种新的、可记录各种参数的颌位记录托盘。方法:对100副在临床应用的全口义齿,测量双侧上颌第一磨牙中央窝间距a1、上颌第一磨牙中央窝连线至义齿前缘距离a2、上颌义齿宽度a3、上颌义齿长度a4、右上颌第一磨牙近中舌尖至基托组织面高度a51、右下颌第一磨牙中央窝至基托组织面高度a52、上唇系带切迹至上颌中切牙切端连线的高度a6、上中切牙区唇侧基托最薄处厚度a7,并以此设计颌位记录托盘支撑杆孔间距b1、支撑杆孔至托盘前缘距离b2、托盘宽度b3、托盘长度b4、上颌后牙区托台高度b51、支撑杆高度b52、前部手柄高度b6、前部手柄厚度b7,以制作不同型号的颌位记录托盘。结果:各组数据的最小值、平均值、最大值(单位:mm)分别如下:a1:37.1、44.5、59.6;a2:22.6、29.0、38.1;a3:48.5、58.2、76.6;a4:37.4、50.8、61.0;a51:5.6、9.5、14.7;a52:3.8、9.9、18.8;a6:8.9、16.6、24.7;a7:1.2、2.8、5.9。设计大、中、小3种号型的颌位记录托盘。临床应用时,首先在托盘组织面用硅橡胶重衬,托台平面和前部手柄下缘确定牙合平面;继而安装下颌支撑杆,旋转螺丝至合适的垂直距离;然后在支撑杆前后放置硅橡胶,确定水平关系;最后在前部手柄唇侧画线标记面部中线及微笑、静息时上唇下缘位置。结论:本研究测量的全口义齿数据对分析修复空间提供了参考,本研究设计的托盘为无牙颌患者全口义齿修复时确定颌位关系提供了一种新方法。 展开更多
关键词 无牙 义齿 全口 颌位关系 义齿修复术
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3种方法记录水平颌位关系的全口义齿咀嚼效率对比研究 被引量:8
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作者 徐婷婷 高旭 +1 位作者 韩晓兰 凤渝蓉 《安徽医科大学学报》 CAS 北大核心 2012年第10期1254-1256,共3页
采用自身对照研究,每位患者制作3种水平颌位关系记录的全口义齿,利用吸光度法检测3种全口义齿的咀嚼效率,对结果进行统计学分析。在哥特式弓轨迹顶点(正中关系位)建牙合的全口义齿与直接咬合法确定颌位的全口义齿的咀嚼效率高于由哥特... 采用自身对照研究,每位患者制作3种水平颌位关系记录的全口义齿,利用吸光度法检测3种全口义齿的咀嚼效率,对结果进行统计学分析。在哥特式弓轨迹顶点(正中关系位)建牙合的全口义齿与直接咬合法确定颌位的全口义齿的咀嚼效率高于由哥特式弓轨迹顶点往前1 mm建牙合的全口义齿,差异有统计学意义(P<0.05);3种方法记录水平颌位关系的全口义齿的咀嚼效率调牙合后比调牙合前皆有所提高,差异有统计学意义(P<0.05)。 展开更多
关键词 全口义齿 颌位关系记录 咀嚼效率
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内吗啡肽研究进展 被引量:12
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作者 任维华 霍笑风 +1 位作者 吴宁 王锐 《中国药理学通报》 CAS CSCD 北大核心 2001年第1期17-20,共4页
1997年发现的内吗啡肽 (Endomorphins、EMs) ,结构上属于四肽 ,被认为是 μ阿片受体 (MOR)的内源性配基 ,它通过与G蛋白偶联的MOR受体结合介导许多生理活动 ,本文结合本实验室对内吗啡肽的研究 ,对其神经系统分布、受体结合特性、生理... 1997年发现的内吗啡肽 (Endomorphins、EMs) ,结构上属于四肽 ,被认为是 μ阿片受体 (MOR)的内源性配基 ,它通过与G蛋白偶联的MOR受体结合介导许多生理活动 ,本文结合本实验室对内吗啡肽的研究 ,对其神经系统分布、受体结合特性、生理作用。 展开更多
关键词 内吗啡肽 Μ阿片受体 受体结合特性 构效关系
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带约束拉杆矩形钢管混凝土的本构关系 被引量:26
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作者 蔡健 龙跃凌 《工程力学》 EI CSCD 北大核心 2008年第2期137-143,共7页
对带约束拉杆矩形钢管混凝土在轴压下的受力机理进行分析,在带约束拉杆方形钢管混凝土本构关系的基础上,针对矩形钢管截面长边、短边对混凝土约束作用大小不同及约束拉杆沿长边、短边布置数量不同等特点,应用基于混凝土真三轴试验的破... 对带约束拉杆矩形钢管混凝土在轴压下的受力机理进行分析,在带约束拉杆方形钢管混凝土本构关系的基础上,针对矩形钢管截面长边、短边对混凝土约束作用大小不同及约束拉杆沿长边、短边布置数量不同等特点,应用基于混凝土真三轴试验的破坏准则确定核心混凝土的峰值强度,从而提出适合带约束拉杆矩形钢管混凝土柱数值计算的本构关系,并根据相关试验结果对本构关系的参数进行确定。应用该本构关系对有关试件进行荷载-应变关系的全过程计算,并与试验结果比较,两者吻合良好。 展开更多
关键词 本构关系 矩形钢管混凝土 约束拉杆 约束作用 破坏准则
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基于启发式方法和支持向量机方法预测药物与人血浆蛋白结合率 被引量:10
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作者 司宏宗 姚小军 +4 位作者 刘焕香 王杰 李加忠 胡之德 刘满仓 《化学学报》 SCIE CAS CSCD 北大核心 2006年第5期415-422,共8页
应用启发式方法和支持向量机方法建立了70种药物与血浆蛋白结合率的定量构效关系模型,研究了分子结构对药物与血浆蛋白结合率的影响.两种方法均得到了较好的结果,交互检验的相关系数平方分别为0.80和0.82;通过对模型的稳定性和预测能力... 应用启发式方法和支持向量机方法建立了70种药物与血浆蛋白结合率的定量构效关系模型,研究了分子结构对药物与血浆蛋白结合率的影响.两种方法均得到了较好的结果,交互检验的相关系数平方分别为0.80和0.82;通过对模型的稳定性和预测能力比较,支持向量机建立的QSAR模型能够更好地预测药物与血浆蛋白结合率. 展开更多
关键词 定量构效关系 血浆蛋白结合率 支持向量机 启发式回归方法
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带约束拉杆方形钢管混凝土的本构关系 被引量:29
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作者 蔡健 何振强 《工程力学》 EI CSCD 北大核心 2006年第10期145-150,共6页
对带约束拉杆方形钢管混凝土轴压构件的力学机理进行分析,借鉴约束混凝土本构模型,基于等效侧向压应力的概念,提出适合带约束拉杆方形钢管混凝土柱数值计算的核心混凝土本构关系,并结合有关试验结果对本构关系中的参数进行确定。应用该... 对带约束拉杆方形钢管混凝土轴压构件的力学机理进行分析,借鉴约束混凝土本构模型,基于等效侧向压应力的概念,提出适合带约束拉杆方形钢管混凝土柱数值计算的核心混凝土本构关系,并结合有关试验结果对本构关系中的参数进行确定。应用该本构关系对有关试件进行荷载-应变关系全过程计算,计算结果与试验结果比较,两者吻合良好。 展开更多
关键词 本构关系 方形钢管混凝土 约束拉杆 等效侧向压应力 数值方法
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受冻融环境混凝土的应力-应变全曲线试验研究 被引量:35
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作者 段安 钱稼茹 《混凝土》 CAS CSCD 北大核心 2008年第8期13-16,共4页
为研究受冻融循环作用的混凝土受压应力-应变关系,按照GBJ 82—85规定的快速冻融试验方法,对3批共85个尺寸为100 mm×100 mm×300 mm的混凝土棱柱体试件进行了冻融循环,试件的变化参数为混凝土立方体抗压强度和冻融循环次数;然... 为研究受冻融循环作用的混凝土受压应力-应变关系,按照GBJ 82—85规定的快速冻融试验方法,对3批共85个尺寸为100 mm×100 mm×300 mm的混凝土棱柱体试件进行了冻融循环,试件的变化参数为混凝土立方体抗压强度和冻融循环次数;然后对试件进行了单轴抗压破坏试验。结果表明:随着冻融循环次数增加,混凝土的受压应力-应变曲线渐趋扁平,峰值应力降低,峰值应变增大;冻融循环次数相同时,混凝土立方体抗压强度高的试件,其峰值应力降低程度和峰值应变增大程度小于混凝土强度低的试件。回归试验结果,提出了适用于立方体抗压强度为30~50 MPa的受冻融循环作用混凝土的应力-应变全曲线方程及确定其参数的公式。 展开更多
关键词 混凝土 冻融循环 受压应力-应变全曲线
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