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神经肽S受体基因多态性与原发性失眠的相关性研究
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作者 范杰 惠培林 +7 位作者 马薇 王旭斌 赵媛 王金凤 陈雪萍 苏晓艳 郭斌 谢宇平 《中国现代医生》 2024年第21期1-5,46,共6页
目的探讨神经肽S受体(neuropeptide S receptor,NPSR)基因单核苷酸多态性(single nucleotide polymorphism,SNP)位点(rs323917、rs323920、rs323922、rs2530547、rs324957)与原发性失眠(primary insomnia,PI)的相关性。方法选取2016年1... 目的探讨神经肽S受体(neuropeptide S receptor,NPSR)基因单核苷酸多态性(single nucleotide polymorphism,SNP)位点(rs323917、rs323920、rs323922、rs2530547、rs324957)与原发性失眠(primary insomnia,PI)的相关性。方法选取2016年12月至2019年5月在甘肃省人民医院睡眠医学中心门诊就诊并确诊的PI患者157例作为PI组,选取同期133名健康体检者作为对照组。抽取受试者的静脉血标本,并提取DNA、聚合酶链反应(polymerase chain reaction,PCR)扩增、琼脂糖凝胶电泳,目标位点测序对rs323917、rs323920、rs323922、rs2530547、rs324957单核苷酸位点进行基因分型,同时行标准多导睡眠监测,分析基因多态性与PI的相关性。结果两组受试者的NPSR SNP位点(rs323917、rs323920、rs323922、rs2530547)基因型分布和等位基因频率及rs324957等位基因频率的差异均无统计学意义(P>0.05);rs324957位点基因型分布差异有统计学意义(P=0.034);两组受试者不同单倍型频率差异无统计学意义(P>0.05)。结论NPSR rs324957 SNP位点基因型表达或与PI相关,且以AG基因型为主。 展开更多
关键词 神经肽s 原发性失眠 单核苷酸多肽性
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Impact of cognition-related single nucleotide polymorphisms on brain imaging phenotype in Parkinson’s disease
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作者 Ting Shen Jia-Li Pu +7 位作者 Ya-Si Jiang Yu-Mei Yue Ting-Ting He Bo-Yi Qu Shuai Zhao Ya-Ping Yan Hsin-Yi Lai Bao-Rong Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第5期1154-1160,共7页
Multiple single nucleotide polymorphisms may contribute to cognitive decline in Parkinson’s disease. However, the mechanism by which these single nucleotide polymorphisms modify brain imaging phenotype remains unclea... Multiple single nucleotide polymorphisms may contribute to cognitive decline in Parkinson’s disease. However, the mechanism by which these single nucleotide polymorphisms modify brain imaging phenotype remains unclear. The aim of this study was to investigate the potential effects of multiple single nucleotide polymorphisms on brain imaging phenotype in Parkinson’s disease. Forty-eight Parkinson’s disease patients and 39 matched healthy controls underwent genotyping and 7 T magnetic resonance imaging. A cognitive-weighted polygenic risk score model was designed, in which the effect sizes were determined individually for 36 single nucleotide polymorphisms. The correlations between polygenic risk score, neuroimaging features, and clinical data were analyzed. Furthermore, individual single nucleotide polymorphism analysis was performed to explore the main effects of genotypes and their interactive effects with Parkinson’s disease diagnosis. We found that, in Parkinson’s disease, the polygenic risk score was correlated with the neural activity of the hippocampus, parahippocampus, and fusiform gyrus, and with hippocampal-prefrontal and fusiform-temporal connectivity, as well as with gray matter alterations in the orbitofrontal cortex. In addition, we found that single nucleotide polymorphisms in α-synuclein(SNCA) were associated with white matter microstructural changes in the superior corona radiata, corpus callosum, and external capsule. A single nucleotide polymorphism in catechol-O-methyltransferase was associated with the neural activities of the lingual, fusiform, and occipital gyri, which are involved in visual cognitive dysfunction. Furthermore, DRD3 was associated with frontal and temporal lobe function and structure. In conclusion, imaging genetics is useful for providing a better understanding of the genetic pathways involved in the pathophysiologic processes underlying Parkinson’s disease. This study provides evidence of an association between genetic factors, cognitive functions, and multi-modality neuroimaging biomarkers in Parkinson’s disease. 展开更多
关键词 COGNITION imaging genetics magnetic resonance imaging MULTI-MODALITY Parkinson’s disease polygenic risk score single nucleotide polymorphism ultra-high field
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Application of single-cell omics in inflammatory bowel disease
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作者 Hengqi Betty Zheng 《World Journal of Gastroenterology》 SCIE CAS 2023年第28期4397-4404,共8页
Over the past decade,the advent of single cell RNA-sequencing has revolutionized the approach in cellular transcriptomics research.The current technology offers an unbiased platform to understand how genotype correlat... Over the past decade,the advent of single cell RNA-sequencing has revolutionized the approach in cellular transcriptomics research.The current technology offers an unbiased platform to understand how genotype correlates to phenotype.Single-cell omics applications in gastrointestinal(GI)research namely inflammatory bowel disease(IBD)has become popular in the last few years with multiple publications as single-cell omics techniques can be applied directly to the target organ,the GI tract at the tissue level.Through examination of mucosal tissue and peripheral blood in IBD,the recent boom in single cell research has identified a myriad of key immune players from enterocytes to tissue resident memory T cells,and explored functional heterogeneity within cellular subsets previously unreported.As we begin to unravel the complex mucosal immune system in states of health and disease like IBD,the power of exploration through single-cell omics can change our approach to translational research.As novel techniques evolve through multiplexing single-cell omics and spatial transcriptomics come to the forefront,we can begin to fully comprehend the disease IBD and better design targets of treatment.In addition,hopefully these techniques can ultimately begin to identify biomarkers of therapeutic response and answer clinically relevant questions in how to tailor individual therapy to patients through personalized medicine. 展开更多
关键词 single-cell omics Inflammatory bowel disease Crohn’s disease Ulcerative colitis single cell RNA-sequencing Precision medicine
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Semiconducting SWCNT Photo Detector for High Speed Switching Through Single Halo Doping
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作者 A.Arulmary V.Rajamani T.Kavitha 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1617-1630,共14页
The method opted for accuracy,and no existing studies are based on this method.A design and characteristic survey of a new small band gap semiconducting Single Wall Carbon Nano Tube(SWCNT)Field Effect Transistor as a ... The method opted for accuracy,and no existing studies are based on this method.A design and characteristic survey of a new small band gap semiconducting Single Wall Carbon Nano Tube(SWCNT)Field Effect Transistor as a photodetector is carried out.In the proposed device,better performance is achieved by increasing the diameter and introducing a new single halo(SH)doping in the channel length of the CNTFET device.This paper is a study and analysis of the performance of a Carbon Nano Tube Field Effect Transistor(CNTFET)as a photodetector using the self-consistent Poisson and Green function method.The 2D self-consistent Poisson and Green’s function method for various optical intensities and wavelength simulate this proposed photodetector.The performance study is based on the simulation of drain current,transconductance,sub-threshold swing,cut-off frequency,gain,directivity,and quantum efficiency under dark and illuminated conditions.These quantum simulation results show that cut-off frequency increases while there is an increase in diameter.The proposed SH-CNTFET provides better performance in terms of higher gain and directivity than conventional CNTFET(C-CNTFET).This device will be helpful in optoelectronic integrated circuits(OEIC)receivers due to its superior performance. 展开更多
关键词 single halo CNTFET self-consistent poisson equation green’s function photodetector
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On the Creation Background and the Influence of Wei Zhuang’s Famous Poem:Lament of a Northwestern Woman
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作者 Liu Huo 《Contemporary Social Sciences》 2023年第4期109-120,共12页
Lament of a Northwestern Woman(Qin Fu Yin),composed by Wei Zhuang after the Huangchao uprising,is a long poem that showcases the sufferings of the civilians and embodies the people’s character of the poem,which is th... Lament of a Northwestern Woman(Qin Fu Yin),composed by Wei Zhuang after the Huangchao uprising,is a long poem that showcases the sufferings of the civilians and embodies the people’s character of the poem,which is the profound empathy and compassion of the poet towards the civilians’plight.The poem was written during the reign of Emperor Xizong of the Tang Dynasty in the year Gengmao(883 AD).2023 is also the year Gengmao,so this poem has existed for a remarkable 1140 years.For over a millennium,this long poem remained submerged in history until the opening of the Dunhuang Grottoes at the turn of the 20th century.The deep compassion and commiseration towards the underprivileged masses conveyed in this long poem are reminiscent of Du Fu’s renowned“Three Poems of Separation.”Moreover,it is widely believed that this poem foretells the decline of the Tang Dynasty. 展开更多
关键词 Lament of a Northwestern woman Wei Zhuang people’s character the decline of the Tang Dynasty
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A cascade of in situ conversion of bicarbonate to CO_(2) and CO_(2) electroreduction in a flow cell with a Ni-N-S catalyst
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作者 Linghui Kong Min Wang +6 位作者 Yongxiao Tuo Shanshan Zhou Jinxiu Wang Guangbo Liu Xuejing Cui Jiali Wang Luhua Jiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期183-193,I0005,共12页
Combination of CO_(2) capture using inorganic alkali with subsequently electrochemical conversion of the resultant HCO_(3)^(-)to high-value chemicals is a promising route of low cost and high efficiency.The electroche... Combination of CO_(2) capture using inorganic alkali with subsequently electrochemical conversion of the resultant HCO_(3)^(-)to high-value chemicals is a promising route of low cost and high efficiency.The electrochemical reduction of HCO_(3)^(-)is challenging due to the inaccessible of negatively charged molecular groups to the electrode surface.Herein,we adopt a comprehensive strategy to tackle this challenge,i.e.,cascade of in situ chemical conversion of HCO_(3)^(-)to CO_(2) and CO_(2) electrochemical reduction in a flow cell.With a tailored Ni-N-S single atom catalyst(SACs),where sulfur(S)atoms located in the second shell of Ni center,the CO_(2)electroreduction(CO_(2)ER)to CO is boosted.The experimental results and density functional theory(DFT)calculations reveal that the introduction of S increases the p electron density of N atoms near Ni atom,thereby stabilizing^(*)H over N and boosting the first proton coupled electron transfer process of CO_(2)ER,i.e.,^(*)+e^(-)+^(*)H+^(*)CO_(2)→^(*)COOH.As a result,the obtained catalyst exhibits a high faradaic efficiency(FE_(CO)~98%)and a low overpotential of 425 mV for CO production as well as a superior turnover frequency(TOF)of 47397 h^(-1),outcompeting most of the reported Ni SACs.More importantly,an extremely high FECOof 90%is achieved at 50 mA cm^(-2)in the designed membrane electrode assembly(MEA)cascade electrolyzer fed with liquid bicarbonate.This work not only highlights the significant role of the second coordination on the first coordination shell of the central metal for CO_(2)ER,but also provides an alternative and feasible strategy to realize the electrochemical conversion of HCO_(3)^(-)to high-value chemicals. 展开更多
关键词 s doped Ni-N-C single atom catalysts CO_(2)electrochemical reduction DFT calculations Membrane electrode assembly Reduction of bicarbonate
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基于S变换相关度的配电网单相接地自适应有源消弧法
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作者 李运旺 陈俊德 +2 位作者 张大平 桑云 韩晓蕾 《电气传动》 2024年第7期86-92,共7页
提出了基于S变换相关度的配电网单向接地自适应有源消弧法,有效消除了配电网单相接地故障电弧,提升了电力系统稳定性。采集配电网线路零序电流时序数据,经S变换获取零序电流时频信息矩阵后,计算并获取各线路间时频信息矩阵相关度矩阵,... 提出了基于S变换相关度的配电网单向接地自适应有源消弧法,有效消除了配电网单相接地故障电弧,提升了电力系统稳定性。采集配电网线路零序电流时序数据,经S变换获取零序电流时频信息矩阵后,计算并获取各线路间时频信息矩阵相关度矩阵,输入卷积神经网络模型,输出单相接地故障选线结果;在故障线路采用基于模糊准PR与PI控制的双闭环自适应控制方法,向配电网故障线路中性点注入零序电流,有效控制注入电流相位以及幅值,迫使配电网故障线路所在相的电压值为0,完成自适应有源消弧。实验结果表明:该方法可有效识别配电网单相接地故障线路,实现配电网单相接地自适应有源消弧,且可尽快完成单相接地自适应有源消弧工作,保证配电网安全稳定运行。 展开更多
关键词 s变换 相关度 配电网 单相接地故障 自适应 有源消弧
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基于Pearson相关系数与广义S变换的低压直流微电网的故障选线方法 被引量:3
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作者 高淑萍 李晓芳 +2 位作者 宋国兵 郑瀚 郭芳宾 《电力系统保护与控制》 EI CSCD 北大核心 2023年第15期120-129,共10页
针对低压直流微电网线路的故障选线方法的研究有限,提出一种基于Pearson相关系数与广义S变换的故障选线方法。首先,介绍了低压直流微电网的一般组成。在此基础上,研究了低压直流微电网的单极故障以及极间故障的故障特征,提出选线方法,... 针对低压直流微电网线路的故障选线方法的研究有限,提出一种基于Pearson相关系数与广义S变换的故障选线方法。首先,介绍了低压直流微电网的一般组成。在此基础上,研究了低压直流微电网的单极故障以及极间故障的故障特征,提出选线方法,对各线路正负极首末端电流差进行Pearson相关系数计算来确定故障线路。然后对所选故障线路正负线路首端的电流量进行广义S变换,计算出其能量和的比值判别故障极性或者极间故障。最后,在PSCAD/EMTDC中搭建出低压直流微电网模型以输出各线路电流数据,并利用Matlab对数据进行仿真。结果表明,所提选线方法直接有效,且耐受过渡电阻的能力较强。 展开更多
关键词 低压直流微电网 广义s变换 Pearson相关系数 单极故障 故障选线
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谷胱甘肽S-转移酶P1基因多态性与晚期胃癌奥沙利铂联合卡培他滨方案化疗疗效的关系 被引量:1
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作者 董宁宁 韩磊 《现代肿瘤医学》 CAS 北大核心 2023年第24期4572-4575,共4页
目的:探讨谷胱甘肽S-转移酶P1(glutathione S-transferase P1,GSTP1)rs1695基因多态性与晚期胃癌奥沙利铂联合卡培他滨方案(XELOX方案)化疗疗效的相关性。方法:回顾性选择102例晚期胃癌患者,均接受XELOX方案化疗,通过基质辅助激光解吸... 目的:探讨谷胱甘肽S-转移酶P1(glutathione S-transferase P1,GSTP1)rs1695基因多态性与晚期胃癌奥沙利铂联合卡培他滨方案(XELOX方案)化疗疗效的相关性。方法:回顾性选择102例晚期胃癌患者,均接受XELOX方案化疗,通过基质辅助激光解吸电离飞行时间(matrix-assisted laser desorption/ionization time-of-flight,MALDI-TOF)的方法明确GSTP1 rs1695基因分型,分析患者临床病理特征(包括年龄、性别、肿瘤分化程度、部位、ECOG-PS评分、TNM分期)及GSTP1 rs1695基因分型对患者化疗客观有效率(objective response rate,ORR)及疾病进展时间(progression-free survival,PFS)的影响。结果:102例患者中,GSTP1 rs1695 AA基因型、AG基因型、GG基因型所占例数分别为73例(71.6%)、27例(26.5%)、2例(2.0%),携带变异基因型GG/AG化疗ORR高于野生基因型AA(69.0%vs 43.8%,P=0.022),且携带变异基因型GG/AG患者PFS比野生基因型AA更长[6.1个月(95%CI:5.2~7.0)vs 5.1个月(95%CI:4.6~5.6),P=0.028]。患者临床病理特征均与化疗疗效无关,但肿瘤分化程度及TNM分期与PFS有关(P均<0.05)。Cox回归显示,肿瘤分化程度、TNM分期及GSTP1 rs1695是影响PFS的独立因素。结论:GSTP1 rs1695基因型与晚期胃癌患者XELOX方案化疗疗效密切相关,测定GSTP1 rs1695基因型可以为晚期胃癌的个体化治疗提供参考。 展开更多
关键词 晚期胃癌 谷胱甘肽s-转移酶P1 单核苷酸多态性 药物治疗
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The Shaping of Woman's Language and Its Therapeutic Function through Images in "The Yellow Wallpaper"
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作者 袁芳 《科技信息》 2011年第27期194-194,共1页
In Perkins' "The Yellow Wallpaper",the wallpaper acts as woman's language.Through this interaction between the wallpaper and the heroine in in this story,Gilman displays to us women's embarrassin... In Perkins' "The Yellow Wallpaper",the wallpaper acts as woman's language.Through this interaction between the wallpaper and the heroine in in this story,Gilman displays to us women's embarrassing status in family and society,and leaves the reader to think of woman's future. 展开更多
关键词 英语教学 教学方法 阅读教学 翻译教学
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Ureteral Ewing’s sarcoma in an elderly woman: A case report 被引量:2
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作者 Xin-Xin Li Jian-Bin Bi 《World Journal of Clinical Cases》 SCIE 2019年第20期3372-3376,共5页
BACKGROUND Ewing’s sarcoma(ES)is regarded as a skeletal tumor,with few instances of extraskeletal ES.A primary ES in the ureter is extremely rare.CASE SUMMARY We report the case of a 69-year-old woman who presented w... BACKGROUND Ewing’s sarcoma(ES)is regarded as a skeletal tumor,with few instances of extraskeletal ES.A primary ES in the ureter is extremely rare.CASE SUMMARY We report the case of a 69-year-old woman who presented with intermittent flank pain and hematuria and was found to have a mass in the left ureter.Pathology of the excised mass indicated ES.The clinical treatment and pathologic characteristics in this case,and a review of the literature describing ES in the urinary system,are presented.CONCLUSION Due to the rarity and malignancy of ES in ureter,early diagnosis and prompt surgical treatment are critical. 展开更多
关键词 Ewing’s sARCOMA URETER ELDERLY woman FLANK pain HEMATURIA Case report
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Feminism, Patriarchy and Culture Dominance ——A review to "The Woman Warrior
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作者 罗军荣 《广西师范大学学报(哲学社会科学版)》 2002年第S3期13-20,共8页
The Woman Warrior" is an influential book in the 20th century making a thunder of voice in the world to accuse the stereotype of patriarchy and racism, which also shows the Chinese Americans’ difficulty of being... The Woman Warrior" is an influential book in the 20th century making a thunder of voice in the world to accuse the stereotype of patriarchy and racism, which also shows the Chinese Americans’ difficulty of being edged to the cultural cliff. This article analyses the content and the style of the novel to see inside what the writer wants to express and to figure out the real reason of the inequality between sexes and reveal the truth of the western culture dominance. Feminism, Patriarchy and culture are the main factors considered in the article. 展开更多
关键词 FEMINIsM PATRIARCHY woman’s status ORIENTAL MYTH cross CULTURE living
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Three-dimensional stereotactic surface projection in the statistical analysis of single photon emission computed tomography data for distinguishing between Alzheimer's disease and depression 被引量:1
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作者 Eiji Kirino 《World Journal of Psychiatry》 SCIE 2017年第2期121-127,共7页
AIM To evaluate usefulness of single photon emission computed tomography(SPECT) with three-dimensional stereotactic surface projection(3D-SSP) in distinguishing between Alzheimer's disease(AD) and depression.METHO... AIM To evaluate usefulness of single photon emission computed tomography(SPECT) with three-dimensional stereotactic surface projection(3D-SSP) in distinguishing between Alzheimer's disease(AD) and depression.METHODS We studied 43 patients who presented with both depressive symptoms and memory disturbance. Each subject was evaluated using the following:(1) the Minimal Mental State Examination;(2) the Hamilton Rating Scale for Depression;(3) Clinical Global Impression-Severity scale(CGI-S); and(4) SPECT imaging with 3D-SSP.RESULTS The MMSE scores correlated significantly with the maximum Z-scores of AD-associated regions. CGI-S scores correlated significantly with the maximum Z-scores of depression-associated regions. Factor analysis identified three significant factors. Of these, Factor 1 could be interpreted as favouring a tendency for AD, Factor 2 as favouring a tendency for pseudo-dementia, and Factor 3 as favouring a depressive tendency.CONCLUSION We investigated whether these patients could be categorized as types: Type A(true AD), Type B(pseudodementia), Type C(occult AD), and Type D(true depression). The factor scores in factor analysis supported the validity of this classification. Our results suggest that SPECT with 3D-SSP is highly useful for distinguishing between depression and depressed mood in the early stage of AD. 展开更多
关键词 Alzheimer’s disease THREE-DIMENsIONAL sTEREOTACTIC surface projection single photon emission COMPUTED tomography Pseudo-dementia DEPREssION
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Semiconducting single-walled carbon nanotubes synthesized by S-doping 被引量:5
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作者 Z.J.Li L.Wang +2 位作者 Y.J.Su P.Liu Y.F.Zhang 《Nano-Micro Letters》 SCIE EI CAS 2009年第1期9-13,共5页
An approach was presented for synthesis of semiconducting single-walled carbon nanotubes(SWNTs) by sulfur(S) doping with the method of graphite arc discharge. Raman spectroscopy, UV-vis-NIR absorption spectroscopy and... An approach was presented for synthesis of semiconducting single-walled carbon nanotubes(SWNTs) by sulfur(S) doping with the method of graphite arc discharge. Raman spectroscopy, UV-vis-NIR absorption spectroscopy and electronic properties measurements indicated the semconducting properties of the SWNTs samples. Simulant calculation indicated that S doping could induce convertion of metallic SWNTs into semiconducting ones. This strategy may pave a way for the direct synthesis of pure semiconducting SWNTs. 展开更多
关键词 s-doping singlE-WALL Carbon nanotubes sEMICONDUCTING Arc discharge
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A single nucleotide polymorphism in the IL1RL1 gene is associated with Behcet's disease in a Chinese Han population 被引量:1
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作者 Xin-Shu Liu Zi-Yan Wu +7 位作者 Si Chen Chan Zhao Fei Gao Ming-Hang Pei Shan-Shan Jia Yong-Zhe Li Pei-Zeng Yang Mei-Fen Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第9期1315-1320,共6页
AIM:To explore the association of single nucleotide polymorphisms(SNPs)in the IL33/IL1RL1 gene region with the susceptibility to Behcet’s disease(BD)in a Chinese Han population.METHODS:A total of eight SNPs in the ca... AIM:To explore the association of single nucleotide polymorphisms(SNPs)in the IL33/IL1RL1 gene region with the susceptibility to Behcet’s disease(BD)in a Chinese Han population.METHODS:A total of eight SNPs in the candidate gene region(rs11792633,rs7025417,rs10975519 and rs1048274 in IL33;rs2310220,rs12712142,rs13424006 and rs3821204 in IL1RL1)were genotyped in783 BD patients and 701 healthy controls by the Sequenom Mass Array i PLEX platform.RESULTS:A statistically significant association was observed between IL1RL1 rs12712142 and BD patients.The frequency of IL1RL1 rs12712142 variant allele A was significantly lower in BD patients than that in controls(OR=0.8,95%CI:0.69-0.94,Pc=0.039);the genotype distribution(Pc=0.043)and additive and dominant genetic model analyses(OR=0.8,95%CI:0.69-0.94,Pc=0.040 and OR=0.72,95%CI:0.58-0.88,Pc=0.011)also indicated a strong association between rs12712142 and BD patients.CONCLUSION:This is the first study to reveal the association between IL1RL1 rs12712142 variant allele A and the decreased risk of BD in the Chinese Han population,indicating a protective role of IL1RL1 in the pathogenesis of BD. 展开更多
关键词 Behcet’s disease single nucleotide polymorphism Chinese Han population IL33 IL1RL1
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BDS授时性能分析与接收机DCB估计 被引量:3
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作者 陈亮 展昕 +1 位作者 许磊 张志新 《导航定位学报》 CSCD 2023年第1期53-59,共7页
为了进一步研究北斗卫星导航系统(BDS)的授时性能,对北斗三号(BDS-3)多模式授时性能进行分析,给出采用时间群延迟参数的授时处理方法:指出BDS-3播发的导航信号较北斗二号(BDS-2)增加了B1C、B2a和B2b等民用频点,去掉了性能较差的B2I,并... 为了进一步研究北斗卫星导航系统(BDS)的授时性能,对北斗三号(BDS-3)多模式授时性能进行分析,给出采用时间群延迟参数的授时处理方法:指出BDS-3播发的导航信号较北斗二号(BDS-2)增加了B1C、B2a和B2b等民用频点,去掉了性能较差的B2I,并在原有时间群延迟(TGD)参数的基础上增加了TGDB1Cp、TGDB2ap和TGDB2bI等参数,为导航用户提供新频点的延迟改正;然后提出一种特殊情况下的单站接收机差分码偏差(DCB)估计方法,采用连续60 d的观测数据进行BDS-3多模式授时分析。实验结果表明:单频授时精度(RMS)BDS-3较BDS-2提升约5 ns,单频模式受未消除电离层延迟影响严重;单频差分(电离层格网)模式较单频模式有较大改善,相同频点提高约4 ns;双频模式和三频模式表现最优,授时精度优于1ns;全部授时精度优于BDS-3公布的20ns;最后验证估计的接收机DCB在30 d内变化稳定,标准差(STD)不超过0.2 ns。 展开更多
关键词 北斗卫星导航系统(BDs) 授时 单频 双频 差分码偏差
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Modeling and Analysis of Single Machine Scheduling Based on Noncooperative Game Theory 被引量:3
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作者 WANGChang-Jun XIYu-Geng 《自动化学报》 EI CSCD 北大核心 2005年第4期516-522,共7页
Considering the independent optimization requirement for each demander of modernmanufacture, we explore the application of noncooperative game in production scheduling research,and model scheduling problem as competit... Considering the independent optimization requirement for each demander of modernmanufacture, we explore the application of noncooperative game in production scheduling research,and model scheduling problem as competition of machine resources among a group of selfish jobs.Each job has its own performance objective. For the single machine, multi-jobs and non-preemptivescheduling problem, a noncooperative game model is established. Based on the model, many prob-lems about Nash equilibrium solution, such as the existence, quantity, properties of solution space,performance of solution and algorithm are discussed. The results are tested by numerical example. 展开更多
关键词 单机时序 NAsH平衡 工作计划 工作目标 自动化技术
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Y Specific Sequence Gene Analysis of Single Fetal Nucleated Erythroblasts from the Peripheral Blood of Pregnant Women
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作者 王陶然 陈汉平 +1 位作者 卢运萍 马庭元 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2001年第2期163-165,共3页
The single cell isolation technique was used to detect fetal nucleated erythroblasts at a single cell level from the peripheral blood of pregnant women in order to investigate the feasibility of this method for nonin... The single cell isolation technique was used to detect fetal nucleated erythroblasts at a single cell level from the peripheral blood of pregnant women in order to investigate the feasibility of this method for noninvasive prenatal diagnosis. Single fetal nucleated erythroblasts were isolated from the peripheral blood samples from 51 pregnant women by micromanipulation techniques after density gradient centrifugation. Nested polymerase chain reaction method was used to amplify the SRY gene. It was found that the concordance rate of amplification results with real fetal sex was 82.61 %. The sensitivity and specificity were 80 % and 87.50 % respectively. It was suggested that it is feasible and promising in non invasive prenatal diagnosis to detect fetal nucleated erythroblasts at a single cell level by using micromanipulation techniques. 展开更多
关键词 single cell peripheral blood of pregnant woman fetal nucleated erythroblasts nested polymerase chain reaction
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MORPHOLOGY OF(Mn,Fe)S SINGLE CRYSTAL GROWTH IN CAST STEEL
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作者 JIANG Xishan GONG Yansheng ZHANG Guichang Research Institute of Qiqihar Steel Works.Qiqihar,Heilongjiang,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1989年第1期77-80,共4页
The step pattern of single crystal growth and the morphology at equilibrium state of(Mn, Fe)S on the wall of micro-voids in ZG25 cast steel have been observed using scanning electron microscope.The face-centred cubic(... The step pattern of single crystal growth and the morphology at equilibrium state of(Mn, Fe)S on the wall of micro-voids in ZG25 cast steel have been observed using scanning electron microscope.The face-centred cubic(Mn,Fe)S single crystal at equilibrium state is shown to be tetrakaidecahedron consisted of eight{111}planes and six{100}planes,and is a typical example of the O_h—m3m cubic crystal system. 展开更多
关键词 cast steel (Mn Fe)s single crystal growth crystal morphology
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Improved data analysis method of single-molecule experiments based on probability optimization
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作者 翟伟利 袁国华 +1 位作者 刘超 陈虎 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第1期182-187,共6页
To extract the dynamic parameters from single molecule manipulation experiments, usually lots of data at different forces need to be recorded. But the measuring time of a single molecule is limited due to breakage of ... To extract the dynamic parameters from single molecule manipulation experiments, usually lots of data at different forces need to be recorded. But the measuring time of a single molecule is limited due to breakage of the tether or degradation of the molecule. Here we propose a data analysis method based on probability maximizalion of the recorded time trace to extract the dynamic parameters from a single measurement. The feasibility of this method was verified by dealing with the simulation data of a two-state system. We also applied this method to estimate the parameters of DNA hairpin folding and unfolding dynamics measured by a magnetic tweezers experiment. 展开更多
关键词 probability optimization Bell's model DNA hairpin single molecule manipulation
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