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Small cell lung carcinoma with KIF5B-RET fusion partially responded to the 4^(th)-line therapy with anlotinib:A case report
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作者 Rui Zhang Yu-Ting He +2 位作者 Yi-Sha Liu Hang Li Feng Zhao 《World Journal of Clinical Cases》 SCIE 2024年第23期5410-5415,共6页
BACKGROUND Small cell lung cancer(SCLC)exhibits a pronounced tendency for metastasis and relapse,and the acquisition of resistance to chemotherapy and radiotherapy,leading to complexity in treatment outcomes.It is cru... BACKGROUND Small cell lung cancer(SCLC)exhibits a pronounced tendency for metastasis and relapse,and the acquisition of resistance to chemotherapy and radiotherapy,leading to complexity in treatment outcomes.It is crucial to tackle these challenges by advancing targeted therapeutic approaches in ongoing research endeavors.Variant RET fusions have been reported in several solid tumors,but are rarely reported in SCLC.CASE SUMMARY We present the first case of a KIF5B-RET fusion in a 65-year-old male patient with SCLC.To date,the patient has received the 4th line chemotherapy with anlotinib for one year and has shown a sustained favorable partial response.According to the results of next generation sequencing,this SCLC patient harbors the KIF5BRET fusion,suggesting that RET fusion could serve as a promising molecular target for SCLC treatment.Next-generation sequencing(NGS)plays a critical rolein comprehensively assessing the genotype and phenotype of cancer.CONCLUSION NGS can provide SCLC patients with personalized and targeted therapy options,thereby improving their likelihood of survival. 展开更多
关键词 KIF5B-RET fusion Small cell lung cancer Anlotinib Partial response Next-generation sequencing Case report
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Highly pathogenic avian influenza A(H5N1)virus outbreak in Peru in 2022-2023
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作者 Nieves Sevilla Wendy Lizarraga +7 位作者 Victor Jimenez-Vasquez Veronica Hurtado Iris S.Molina Lilian Huarca Priscila Lope-Pari Ivan Vargas Gloria Arotinco Carlos Padilla-Rojas 《Infectious Medicine》 2024年第2期113-118,共6页
Background:An epizootic of highly pathogenic avian influenza A(H5N1)has spread worldwide since 2022.Even though this virus has been extensively studied for many decades,little is known about its evolution in South Ame... Background:An epizootic of highly pathogenic avian influenza A(H5N1)has spread worldwide since 2022.Even though this virus has been extensively studied for many decades,little is known about its evolution in South America.Methods:Here,we describe the sequencing and characterization of 13 H5N1 genomes collected from wild birds,poultry,and wild mammals in Peru during the genomic surveillance of this outbreak.Results:The samples belonged to the highly pathogenic avian influenza(H5N1)2.3.4.4b clade.Chilean and Peruvian samples clustered in the same group and therefore share a common ancestor.An analysis of the hemag-glutinin and neuraminidase genes detected new mutations,some dependent upon the host type.Conclusions:The genomic surveillance of highly pathogenic avian influenza is necessary to promote the One Health policy and to overcome the new problems entailed by climate change,which may alter the habitats of resident and migratory birds. 展开更多
关键词 Avian influenza A H5N1 HPAI Clade 2.3.4.4b sequencing 2022-2023 outbreak
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血清FAM19A5、IL-34在血管性认知障碍患者中的表达及临床意义
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作者 张永慧 孙咏捷 +2 位作者 郝喜娃 梁芙茹 李月春 《疑难病杂志》 CAS 2024年第9期1060-1064,1069,共6页
目的探讨血清序列相似家族19成员5(FAM19A5)、白介素-34(IL-34)在血管性认知障碍(VCI)患者中的表达及临床意义。方法选取2020年1月—2022年12月包头市中心医院神经内科收治的非痴呆血管性认知损害(VCIND)患者125例(VCIND组)和同期体检... 目的探讨血清序列相似家族19成员5(FAM19A5)、白介素-34(IL-34)在血管性认知障碍(VCI)患者中的表达及临床意义。方法选取2020年1月—2022年12月包头市中心医院神经内科收治的非痴呆血管性认知损害(VCIND)患者125例(VCIND组)和同期体检健康者58例(健康对照组),VCIND组患者随访1年根据是否进展为血管性痴呆(VaD)分为VaD亚组45例和非VaD亚组80例,采用酶联免疫吸附法检测血清FAM19A5、IL-34水平。通过多因素Logistic回归分析VCIND进展至VaD的影响因素,ROC曲线分析血清FAM19A5、IL-34水平对VCIND进展至VaD的预测能效。结果与健康对照组比较,VCIND组血清FAM19A5水平升高,IL-34水平降低(t=19.808、15.706,P均<0.001)。随访1年,125例VCIND患者VaD发生率为36.00%(45/125)。与非VaD亚组比较,VaD亚组血清FAM19A5水平升高,IL-34水平降低(t=7.100、5.952,P均<0.001)。Logistic回归分析结果表明,年龄增加(OR=1.137,95%CI 1.014~1.275)、FAM19A5升高(OR=1.079,95%CI 1.040~1.119)为VCIND进展至VaD的独立危险因素(P<0.05),蒙特利尔认知评估量表评分增加(OR=0.603,95%CI 0.437~0.832)、IL-34升高(OR=0.737,95%CI 0.624~0.870)为独立保护因素(P<0.05)。血清FAM19A5、IL-34水平联合预测VCIND进展至VaD的曲线下面积为0.880,大于血清FAM19A5、IL-34水平单独预测的0.813、0.781(Z=2.529、2.855,P均<0.05)。结论血清FAM19A5水平升高和IL-34水平降低与VCIND进展至VaD密切相关,血清FAM19A5、IL-34水平联合检测对VCIND进展至VaD有较高的预测效能。 展开更多
关键词 血管性认知障碍 序列相似家族19成员5 白介素-34 预测价值
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绵羊Fsp27基因5'-UTR区碱基突变与尾脂沉积能力的关联性 被引量:1
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作者 张伟 王世银 +3 位作者 高莉 徐梦思 王新华 甘尚权 《南方农业学报》 CAS CSCD 北大核心 2020年第7期1511-1519,共9页
【目的】明确绵羊脂肪特异蛋白27基因(Fsp27)5'端非编码区(5'-UTR)g.16767527位点和g.16767779-16767780位点突变与其尾脂沉积能力的关联性,为低脂肪绵羊品种选育提供理想的分子标记,提高低脂肪绵羊品种改良选育效率。【方法】... 【目的】明确绵羊脂肪特异蛋白27基因(Fsp27)5'端非编码区(5'-UTR)g.16767527位点和g.16767779-16767780位点突变与其尾脂沉积能力的关联性,为低脂肪绵羊品种选育提供理想的分子标记,提高低脂肪绵羊品种改良选育效率。【方法】以5个不同尾脂沉积能力的绵羊品种为研究对象,包括脂尾型绵羊品种阿勒泰羊,短脂尾型绵羊品种小尾寒羊和湖羊,长瘦尾型绵羊品种中国美利奴细毛羊和萨福克羊,采用PCR-SSCP结合基因测序对绵羊Fsp27基因5'-UTR区碱基突变情况进行检测,并分析相关突变与绵羊尾脂沉积能力的关联性。【结果】绵羊Fsp27基因5'-UTR区g.16767527位点为C/A突变,在所检测的绵羊群体中均存在3种基因型(CC、CA和AA),但在不同尾脂沉积能力绵羊品种群体中的基因型频率存在明显差异:阿勒泰羊群体中以CC基因型为主,基因型频率为0.869;小尾寒羊和湖羊群体中以CA基因型为主,基因型频率分别为0.698和0.628;中国美利奴细毛羊和萨福克羊群体则以AA基因型为主,基因型频率分别为0.616和0.833。g.16767527位点的基因型分布在阿勒泰羊、小尾寒羊和湖羊群体中极显著偏离Hardy-Weinberg平衡状态(PHWE<0.01),在萨福克羊群体中显著偏离Hardy-Weinberg平衡状态(PHWE<0.05)。g.16767779-16767780位点为双碱基突变,对应为GG/GG、GG/TC和TC/TC基因型;在尾脂沉积能力强的阿勒泰羊、小尾寒羊和湖羊群体中,g.16767779-16767780位点以TC为优势等位基因,对应的等位基因频率分别为0.862、0.954和0.927;在尾脂沉积能力差的中国美利奴细毛羊和萨福克羊群体中则以GG等位基因为主,其等位基因频率分别为0.980和0.983。这2个位点的突变均对绵羊Fsp27基因5'-UTR区二级结构产生明显影响。【结论】绵羊Fsp27基因5'-UTR区g.16767527位点的C/A突变和g.16767779-16767780位点的GG/TC突变与其尾脂沉积能力密切相关,可作为分子标记应用于低脂肪绵羊品种的辅助选育。 展开更多
关键词 绵羊 Fsp27基因 5'-utr 碱基突变 尾脂沉积能力 关联性
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Sequence variability of the 5, UTR in isolates of hepatitis C virus in China 被引量:1
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作者 Yuan-Ding Chen Ming-Ying Liu +6 位作者 Wen-Lin Yu Jia-Qi Li Mei Peng Qing Dai Jun Wu Xiao Liu Zhen-Quan Zhou the Key Laboratory, Institute of Medical Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Kunming 650118, China and Kunming Hospital for Infectious Diseases, Kunming 650041, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2002年第4期541-552,共12页
Background: Hepatitis C virus infection is a great is- sue in China; however, there is very little informa- tion on genotyping investigations based on sequence variability in the 5' untranslated (5'UTR) report... Background: Hepatitis C virus infection is a great is- sue in China; however, there is very little informa- tion on genotyping investigations based on sequence variability in the 5' untranslated (5'UTR) reported. The present study was to define the sequence varia- bility based on the sequence divergences of the 5' UTR of the virus. Methods: Sequences of 91 isolates from patients with chronic hepatitis C from Yunnan, southwest China, were sequenced and genotypes were defined accord- ing to the sequence divergences of the 5' UTR of the virus. Results: Eighty-six isolates were classified into 3 clades (previously termed groups or major types) by the methods proposed by Chan et al in 1992 and phy- logenetic analysis based on nucleotide sequence diver- gences within the 5' UTR. Fifty-six percent of the i- solates were classified into clade 3, 35% into clade 1, and 34.9% into clade 2. New genotypes 1f, 2h, 3h and 3i were defined. In addition, 3 novel sequences were discovered, respectively with an 18-nt sequence deletion (corresponding to nucleotide position -173 to -156), a 28-nt sequence insertion, and a 40-nt se- quence insertion, between -56 and -55. Of these i- solates, 56% possessed a 'G' at position -66 in place of the 'T' that is present in all previously re- ported sequences. Conclusions: These HCV variants, evolved or re- mained in this area, may be of great significance in diagnosis and treatment of hepatitis C patients. 展开更多
关键词 hepatitis C pepatitis C virus 5' UTR sequence variability GENOTYPES China
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Grain-size Characteristics and Climate Variability in TMS5e Sequence of Tumen Section in Southern Tengger Desert,Northwestern China 被引量:2
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作者 WEN Xiaohao LI Baosheng +4 位作者 WANG Fengnian ZHENG Yanming NIU Dongfeng SI Yuejin OU Xianjiao 《Chinese Geographical Science》 SCIE CSCD 2012年第1期48-62,共15页
The TMS5e sequence from the Tumen section, at the southern edge of Tengger Desert in the northwestern China, is synchronous with Marine Isotope Stage 5e (MIS5e). It consists of 16 layers of aeolian dune sands, 11 la... The TMS5e sequence from the Tumen section, at the southern edge of Tengger Desert in the northwestern China, is synchronous with Marine Isotope Stage 5e (MIS5e). It consists of 16 layers of aeolian dune sands, 11 layers of lacustrine loess-like facies, and 5 layers of lacustrine facies. The results of grain-size analysis shows that the pa- laeo-mobile dune sands, palaeo-fixed to semi-fixed dune sands and loess-like sandy loams are mainly composed of sands, ranging from 70% to 96%; their silt contents ranged from 4% to 20%, and their clay contents ranged from 1% to 5%; the climate under which the aeolian dune sands were deposited is similar to that under which modern mobile dune sands form, which is caused by the dominance of the cold, dry East Asian winter monsoon. In contrast, the lacustrine loess-like facies and lacustrine facies had a lower sand contents than those of the three aeolian dune sands, but have higher silt and clay contents, most of their sand content ranged from 30% to 60%, their silt contents ranged from 35% to 55%, and their clay contents ranged from 6% to 20%. The lacustrine loess-like facies and lacustrine facies formed under the influence of the warm, humid East Asian summer monsoon based on their similarity with modern sediments. The grain-size indicator Mz (mean grain diameter) and the SC/D value in the TMS5e sequence indicate climatic insta- bility at the southern edge of the Tengger Desert during MIS5e, with at least 14 fluctuations between a warm, humid climate and a cold, dry climate, divided into five stages: TMS5e5 (139 kyr to 129.3 kyr B.P.), TMS5e4 (129.3 kyr to 124 kyr B.P.), TMS5e3 (124 kyr to 119.5 kyr B.P.), TMS5e2 (119.5 kyr to 116.5 kyr B.P.), and TMS5el (116.5 kyr to 113.7 kyr B.P.). These correspond roughly to MIS5e5, MIS5e4, MIS5e3, MIS5e2, and MIS5el, respectively, in the GRIP ice core data. 展开更多
关键词 Tengger Desert Tureen section TMS5e sequence grain-size characteristics palaeoclimate reconstruction Marine Isotope Stage 5e (MIS5e)
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Effect of Impregnation Sequence on Propane Dehydrogenation Performance of PtSnNa/ZSM-5 Catalyst 被引量:1
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作者 Liu Hui Zhou Yuming +3 位作者 Zhang Yiwei Sheng Xiaoli Zhang Zewu Zhou Shijiang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第4期54-62,共9页
The effects of the sequence for impregnation of metal precursors on the performance of PtSnNa/ZSM-5 catalyst for propane dehydrogenation to propene were studied in this paper.Some methods such as XRD,TPDA,BET,H2-TPR,X... The effects of the sequence for impregnation of metal precursors on the performance of PtSnNa/ZSM-5 catalyst for propane dehydrogenation to propene were studied in this paper.Some methods such as XRD,TPDA,BET,H2-TPR,XPS,ICP,TEM and hydrogen chemisorption were used to characterize the catalysts.The structure of ZSM-5 zeolite was not destroyed by the introduction of metal components.Meanwhile the different impregnation sequence of metal precursors could affect the behavior of Sn4+species entering the ZSM-5 channel,and the interaction between platinum and tin species,as well as the degree for reduction of Pt and Sn components.As a result,the prepared catalysts exhibited different reaction activity and selectivity.Compared with the co-impregnation treated catalyst,the catalysts prepared by the sequential impregnation method showed better catalytic activity in propane dehydrogenation,especially the one prepared through impregnation with tin precursor at first.Finally,a model for the effect of impregnation sequence on the distribution of Pt and Sn species in PtSnNa/ZSM-5 catalyst was proposed. 展开更多
关键词 impregnation sequence propane dehydrogenation PtSnNa/ZSM-5 PROPENE
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The circ_0002538/miR-138-5p/plasmolipin axis regulates Schwann cell migration and myelination in diabetic peripheral neuropathy 被引量:7
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作者 Yu-Tian Liu Zhao Xu +10 位作者 Wei Liu Sen Ren He-Wei Xiong Tao Jiang Jing Chen Yu Kang Qian-Yun Li Zi-Han Wu Hans-GüNther Machens Xiao-Fan Yang Zhen-Bing Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1591-1600,共10页
Circular RNAs(circRNAs)play a vital role in diabetic peripheral neuropathy.However,their expression and function in Schwann cells in individuals with diabetic peripheral neuropathy remain poorly understood.Here,we per... Circular RNAs(circRNAs)play a vital role in diabetic peripheral neuropathy.However,their expression and function in Schwann cells in individuals with diabetic peripheral neuropathy remain poorly understood.Here,we performed protein profiling and circRNA sequencing of sural nerves in patients with diabetic peripheral neuropathy and controls.Protein profiling revealed 265 differentially expressed proteins in the diabetic peripheral neuropathy group.Gene Ontology indicated that differentially expressed proteins were mainly enriched in myelination and mitochondrial oxidative phosphorylation.A real-time polymerase chain reaction assay performed to validate the circRNA sequencing results yielded 11 differentially expressed circRNAs.circ_0002538 was markedly downregulated in patients with diabetic peripheral neuropathy.Further in vitro experiments showed that overexpression of circ_0002538 promoted the migration of Schwann cells by upregulating plasmolipin(PLLP)expression.Moreover,overexpression of circ_0002538 in the sciatic nerve in a streptozotocin-induced mouse model of diabetic peripheral neuropathy alleviated demyelination and improved sciatic nerve function.The results of a mechanistic experiment showed that circ_0002538 promotes PLLP expression by sponging miR-138-5p,while a lack of circ_0002538 led to a PLLP deficiency that further suppressed Schwann cell migration.These findings suggest that the circ_0002538/miR-138-5p/PLLP axis can promote the migration of Schwann cells in diabetic peripheral neuropathy patients,improving myelin sheath structure and nerve function.Thus,this axis is a potential target for therapeutic treatment of diabetic peripheral neuropathy. 展开更多
关键词 circ_0002538 circRNA sequencing competing endogenous RNAs DEMYELINATION diabetic peripheral neuropathy miR-138-5 MYELINATION plasmolipin protein profiling Schwann cells
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18种观赏植物F3′5′H基因生物信息学分析 被引量:1
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作者 曾慧兰 高阳 卢毅 《安徽农业科学》 CAS 2023年第7期103-109,共7页
采用生物信息学方法对18种观赏植物类黄酮-3′5′-羟化酶基因(flavonoid-3′5′-hydroxylase,F3′5′H)的mRNA和氨基酸序列的理化性质、跨膜结构域、保守结构域、亚细胞定位、二级结构、三级结构和同源性进行预测与分析。结果表明,绝大... 采用生物信息学方法对18种观赏植物类黄酮-3′5′-羟化酶基因(flavonoid-3′5′-hydroxylase,F3′5′H)的mRNA和氨基酸序列的理化性质、跨膜结构域、保守结构域、亚细胞定位、二级结构、三级结构和同源性进行预测与分析。结果表明,绝大多数观赏植物的F3′5′H为亲水性稳定蛋白质,以α螺旋为主、无信号肽的跨膜蛋白质;大多数定位于内质网膜上;其三级结构模型为5ylw.1.A铁锈醇合成酶,为单链蛋白,属于细胞色素P450基因家族;同源保守氨基酸序列为“LPPGP”“AGTDTS”和“PFGAGRRICAG”。 展开更多
关键词 生物信息学 观赏植物 氨基酸序列 类黄酮-3′5′-羟化酶
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鸡MDA5的序列分析与结构域预测
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作者 庄海彬 李伟强 +7 位作者 黄小武 叶芷羽 丘林峰 林宏文 宋亚婷 丁仰保 黄鉴妮 焦培荣 《中国家禽》 北大核心 2023年第6期36-42,共7页
为了解鸡黑色素瘤分化相关基因-5(Melanoma differentiation-associated protein 5,MDA5)的序列和结构域,试验使用PCR方法扩增了鸡MDA5基因并构建真核表达质粒,实现了鸡MDA5蛋白的真核表达,同时利用MegAlign等软件对鸡MDA5氨基酸序列进... 为了解鸡黑色素瘤分化相关基因-5(Melanoma differentiation-associated protein 5,MDA5)的序列和结构域,试验使用PCR方法扩增了鸡MDA5基因并构建真核表达质粒,实现了鸡MDA5蛋白的真核表达,同时利用MegAlign等软件对鸡MDA5氨基酸序列进行分析。结果显示:鸡MDA5全长3 006 bp,编码1 001个氨基酸;鸡MDA5与人、猕猴、野猪、小鼠、绿头鸭、灰雁、鸿雁、鲫鱼、草鱼的氨基酸相似性分别为62.4%、62.9%、62.7%、64.1%、86.8%、87.3%、87.4%、48.1%、46.3%;鸡MDA5与鸟类进化关系较近,与哺乳动物次之,与鱼类进化关系较远;鸡MDA5由N端两个半胱天冬酶激活招募结构域、DExD/H box RNA解旋酶结构域和C端结构域组成;鸡MDA5二级结构包含α螺旋(50.95%)、延伸链(11.19%)、β转角(3.9%)和无规则卷曲(33.97%),三级结构与人MDA5类似,在空间上呈现半闭合环状结构。研究成功鉴定了鸡MDA5基因,分析了其基因序列并预测其结构域,为深入研究鸡MDA5结构与功能及其在鸡抗病毒天然免疫应答中的作用奠定基础。 展开更多
关键词 鸡黑色素瘤分化相关基因-5 基因克隆 序列分析 结构域预测
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THE ABNORMAL EXPRESSION OF CLONED REPEATED SEQUENCE DNA, L5B-4, IN RAT HEPATOMA BERH-2
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作者 徐亚男 张向阳 +1 位作者 麻孙恺 张玉砚 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期10-17,共8页
A repeated sequence DNA fragment, L5B-4, was cloned from the 5 kb BamHI DNA fragments of rat genomic DNA. The expressions of the L5B-4 DNA fragment are different in liver and hepatoma cells. The amounts of transcripts... A repeated sequence DNA fragment, L5B-4, was cloned from the 5 kb BamHI DNA fragments of rat genomic DNA. The expressions of the L5B-4 DNA fragment are different in liver and hepatoma cells. The amounts of transcripts in hepatoma cells are lower in nucleus and higher in cytoplasm, especially in polysomal RNA, as compared with that in liver cells. The alteration shown in polysomal RNA of hepatoma cells seems to be specific. These results are discussed with respect to the possible function of this repeated DNA and its variation in hepatoma cells. 展开更多
关键词 THE ABNORMAL EXPRESSION OF CLONED REPEATED sequencE DNA IN RAT HEPATOMA BERH-2 L5B-4
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The Reaction Sequence and Dielectric Properties of BaAl<sub>2</sub>Ti<sub>5</sub>O<sub>14</sub>Ceramics
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作者 Xiaogang Yao Wei Chen Lan Luo 《Advances in Materials Physics and Chemistry》 2012年第4期28-30,共3页
To investigate the correct reaction sequence of BaO-Al2O3-5TiO2 system, powders calcined at different temperatures are analyzed by x-ray diffraction. The results show that the source phase BaCO3 decomposes below 800&#... To investigate the correct reaction sequence of BaO-Al2O3-5TiO2 system, powders calcined at different temperatures are analyzed by x-ray diffraction. The results show that the source phase BaCO3 decomposes below 800°C, TiO2 and Al2O3 start to consume at 900 and 1100°C, respectively. BaTi4O9 phase appears at 1000°C while BaAl2Ti5O14 phase starts to reveal at 1200°C. As the temperature increases, the density, dielectric constant and quality factor of the BaAl2Ti5O14 ceramic increase and keep unchanged at 1350°C. The dielectric properties of BaAl2Ti5O14 ceramic sintered at 1350°C for 3h are: εr=35.8, Q×f=5130GHz, τf=-6.8ppm/°C. 展开更多
关键词 REACTION sequencE BaAl2Ti5O14 CERAMICS DIELECTRIC Properties
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3.0T MRI T2Mapping序列对0~5岁正常儿童髋关节软骨评估的探索性分析 被引量:1
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作者 高凯 孙惠苗 +5 位作者 武艳君 杨洁 李佳雯 贾丽峰 杨宏 温家祥 《中国CT和MRI杂志》 2023年第8期167-170,共4页
目的利用3.0T MRI T2Mapping序列对0~5岁正常儿童髋关节软骨行磁共振扫描并量化分析,探究不同阶段髋关节软骨T2值变化规律,初步建立0~5岁正常儿童髋关节软骨T2值的参考范围。方法收集0~5岁发育正常儿童196名,其中男92名,女104名。根据... 目的利用3.0T MRI T2Mapping序列对0~5岁正常儿童髋关节软骨行磁共振扫描并量化分析,探究不同阶段髋关节软骨T2值变化规律,初步建立0~5岁正常儿童髋关节软骨T2值的参考范围。方法收集0~5岁发育正常儿童196名,其中男92名,女104名。根据年龄分成5组,分别对所有儿童行髋关节常规序列、T2-mapping序列扫描,在髋臼软骨及与其对应的股骨头软骨划分上、前、后三个区域,共6个亚区,测量其T2值。观察分析组间及组内不同亚区T2值的差异并计算其正常值范围,分析相关因素。结果0~5岁正常儿童髋关节软骨,不同性别各亚区间T2值比较差异均无统计学意义(均P>0.05)。左、右两侧对应亚区T2值比较差异均无统计学意义(均P>0.05)。不同髋关节亚区各年龄组T2值比较,年龄组间T2值差异有统计学意义(均P<0.05)。结论3.0T MRI T2 mapping序列能定量分析儿童髋关节软骨T2值,0~5岁正常儿童髋关节软骨各亚区软骨T2值与年龄相关,与性别和左右无关。 展开更多
关键词 T2mapping序列 髋关节 软骨 0~5岁正常儿童 T2值
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Differential expression and significance of 5-hydroxymethylcytosine modification in hepatitis B virus carriers and patients with liver cirrhosis and liver cancer
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作者 Yue-Cui Li Wei-Yue Hu +4 位作者 Cheng-Hang Li Li-Li Zhang Xiang-Wei Xu Jin Li Hong-Xia Luo 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第3期346-361,共16页
BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)-positive carrier status and liver cancer has been extensively studied.However,the epigenetic changes that occur during progression from HBsAg-posi... BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)-positive carrier status and liver cancer has been extensively studied.However,the epigenetic changes that occur during progression from HBsAg-positive carrier status or cirrhosis to liver cancer are unknown.The epigenetic modification of DNA hydroxymethylation is critical in tumor development.Further,5-hydroxymethylcytosine(5hmC)is an important base for DNA demethylation and epigenetic regulation.It is also involved in the assembly of chromosomes and the regulation of gene expression.However,the mechanism of action of 5hmC in HBsAgpositive carriers or patients with cirrhosis who develop liver cancer has not been fully elucidated.AIM To investigate the possible epigenetic mechanism of HBsAg-positive carriers and hepatocellular carcinoma(HCC)progression from cirrhosis.METHODS Forty HBsAg-positive carriers,forty patients with liver cirrhosis,and forty patients with liver cancer admitted to the First People's Hospital of Yongkang between March 2020 and November 2021 were selected as participants.Free DNA was extracted using a cf-DNA kit.cfDNA was extracted by 5hmC DNA sequencing for principal component analysis,the expression profiles of the three groups of samples were detected,and the differentially expressed genes(DEGs)modified by hydroxymethylation were screened.Bioinformatic analysis was used to enrich DEGs,such as in biological pathways.RESULTS A total of 16455 hydroxymethylated genes were identified.Sequencing results showed that 32 genes had significant 5hmC modification differences between HBsAg carriers and liver cancer patients,of which 30 were upregulated and 2 downregulated in patients with HCC compared with HBsAg-positive carriers.Significant 5hmC modification differences between liver cirrhosis and liver cancer patients were identified in 20 genes,of which 17 were upregulated and 3 were downregulated in patients with HCC compared with those with cirrhosis.These genes may have potential loci that are undiscovered or unelucidated,which contribute to the development and progression of liver cancer.Analysis of gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes showed that the major signaling pathways involved in the differential genes were biliary secretion and insulin secretion.The analysis of protein interactions showed that the important genes in the protein-protein interaction network were phosphoenolpyruvate carboxykinase and solute carrier family 2.CONCLUSION The occurrence and development of liver cancer involves multiple genes and pathways,which may be potential targets for preventing hepatitis B carriers from developing liver cancer. 展开更多
关键词 Hepatitis B surface antigen 5-hydroxymethylcytosine Hepatocellular carcinoma Liver cancer DNA sequencing Differentially expressed genes
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基于双向门控循环单元的5-甲基胞嘧啶位点预测
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作者 黄修威 方中纯 李海荣 《中南民族大学学报(自然科学版)》 CAS 北大核心 2023年第6期768-774,共7页
5-甲基胞嘧啶(5-methylcytosine,m5C)是一种重要的转录后修饰,大量证据表明,m5C在许多生物学过程中起着至关重要的作用.准确鉴定m5C位点有助于更好地了解其生物学功能.为此提出了一个名为pm5C-BGRU的模型,该模型通过拼接独热编码(One-ho... 5-甲基胞嘧啶(5-methylcytosine,m5C)是一种重要的转录后修饰,大量证据表明,m5C在许多生物学过程中起着至关重要的作用.准确鉴定m5C位点有助于更好地了解其生物学功能.为此提出了一个名为pm5C-BGRU的模型,该模型通过拼接独热编码(One-hot encoding)和核苷酸化学性质(nucleotide chemical property,NCP)进而对RNA序列进行特征提取,并基于双向门控循环单元(Bidirectional Gated Recurrent Unit,BiGRU)来识别m5C位点.将该方法在人类、小鼠和拟南芥三个物种的m5C数据集上进行建模和测试,并对照已有的预测模型进行评估.结果表明,pm5C-BGRU在交叉验证和独立数据集测试中均取得优异效果,该模型有望成为鉴定m5C位点的有力工具. 展开更多
关键词 5-甲基胞嘧啶 序列编码 双向门控循环单元 预测
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投掷动作发展序列与4~5岁幼儿上手投掷 能力的关联性研究
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作者 王贺 庄德 《当代体育科技》 2023年第14期20-23,共4页
该文采用录像解析、数理统计等方法,旨在探究投掷动作发展序列与投掷能力的关联性,以便日后的幼儿体育工作者和研究者运用投掷动作发展序列客观评价幼儿的投掷能力。研究结果:(1)整体序列与投掷距离关联性P=0.005<0.05,y=2.930x+0.41... 该文采用录像解析、数理统计等方法,旨在探究投掷动作发展序列与投掷能力的关联性,以便日后的幼儿体育工作者和研究者运用投掷动作发展序列客观评价幼儿的投掷能力。研究结果:(1)整体序列与投掷距离关联性P=0.005<0.05,y=2.930x+0.411与投掷精准度关联性P=0.301>0.05;(2)部分序列与投掷距离关联性P=0.000<0.001,y=1.378x+0.288与投掷精准度关联性P=0.222>0.05;(3)整体序列与部分序列关联性P=0.000<0.001,y=5.536x+1.354。研究结论:(1)4~5岁幼儿上手投掷动作处于低、中两阶段的人数最多;(2)上手投掷动作序列与投掷距离呈正相关,与投掷精准度无显著相关性;(3)整体序列与部分序列的发展呈正相关。 展开更多
关键词 4~5岁幼儿 上手投掷 动作序列 动作发展 投掷能力
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Analysis on Heredity and Variation of the ORF_5 Gene of Prevalence Strains Porcine Reproductive and Respiratory Syndrome Virus 被引量:5
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作者 尹国友 孙婕 +2 位作者 苏景 陈兰英 赵祯 《Agricultural Science & Technology》 CAS 2009年第5期88-91,共4页
[ Objective] The aim was to analyze the reason and epidemic trend of PRRSV, and provide theoretical basis for preventing and controlling PRRS. [Methed]According to the sequence of ATCC VR-2332 strain porcine reproduct... [ Objective] The aim was to analyze the reason and epidemic trend of PRRSV, and provide theoretical basis for preventing and controlling PRRS. [Methed]According to the sequence of ATCC VR-2332 strain porcine reproductive and respiratory syndrome virus published by the GenBank, the primers were designed and synthesized. ORF5 gene sequences of seven prevalence strains were amplified by RT-PCR. The sequences of ORF5 genes were analyzed by DNAStar and compared with those of ATCC VR-2332, CH-1 a, B J-4, LV-M96262 and MLV vaccine strains, phylogenetic tree among isolates was analyzed. [Result] Analysis of nucleotide sequence showed that the homology was 88.1% - 98.8%, 89.9% -95.2%, 85.6% -98.7% between ORF5 genes of seven prevalence strains and VR-2332, CH-1a, BJ-4, and the homology was 54.7% -56.9% between ORF5 genes and LV. Analysis of amino acid sequence showed that the homology was 88.1% -96.8%, 88.1% - 94.5%, 86.1% -96.5% between ORF5 genes of seven prevalence strains and VR-2332, CH-1a, bBJ-4, the homology was 54.7% -56.2% between the ORF5 genes and LV.[ Conclusion] The variation of prevalence strains was great in the ORF5 gene region, the homology of ORF5 gene sequence was higher and genetic relationship was nearer during prevalence strains in the same region, or was far in different regions. 展开更多
关键词 Porcine reproductive and respiratory syndrome virus ORF5 gene sequence analysis
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牛病毒性腹泻病毒长春分离株P125基因的克隆与序列测定 被引量:5
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作者 骆延波 张绍学 +4 位作者 王新平 宣华 牛钟相 柴家前 王承宇 《中国兽医科技》 CSCD 北大核心 2001年第2期3-6,共4页
以MDBK细胞培养致细胞病变型牛病毒性腹泻病毒 (BVDV)NCD毒株 ,采用异硫氰酸胍一步法提取总RNA ,并根据BVDVNADL参考株序列设计合成的 1对引物 (W 1与W 2 ) ,进行反转录PCR (RT PCR) ,扩增出P12 5基因区约40 0bp的片段。经 pGEM T载体... 以MDBK细胞培养致细胞病变型牛病毒性腹泻病毒 (BVDV)NCD毒株 ,采用异硫氰酸胍一步法提取总RNA ,并根据BVDVNADL参考株序列设计合成的 1对引物 (W 1与W 2 ) ,进行反转录PCR (RT PCR) ,扩增出P12 5基因区约40 0bp的片段。经 pGEM T载体连接后克隆、测序 ,并与已发表的NADL、Osloss、SD 1、184、D、H、Yak等BVDV毒株序列进行比较。结果表明 :NCD株P12 5基因区无插入或缺失变异 ,但存在着核苷酸的替换 ;经聚类分析初步认为NCD株属于Ⅰa型。NCD株与长春 184、H株核苷酸序列差异较大 ,而亲缘关系较近 。 展开更多
关键词 病毒性腹泻病毒 基因克隆 序列测定 致细胞病变型 非致细胞病变型 R25基因
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鳜鱼(Siniperca chuatsi)β-肌动蛋白基因cDNA全序列与5′侧翼区的克隆与分析 被引量:16
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作者 刘秀霞 梁旭方 +3 位作者 王琳 端金霞 李光照 廖婉琴 《海洋与湖沼》 CAS CSCD 北大核心 2009年第1期102-108,共7页
采用RT-PCR及RACE法,分离、克隆鳜鱼β-肌动蛋白基因cDNA全序列,再用基因组步行法(Genome Walker)克隆鳜鱼β-肌动蛋白基因5′调控区。序列分析结果表明,鳜鱼β-肌动蛋白基因全长1897bp,其中5′-UTR长94bp,3′-UTR长675bp,编码区长1128... 采用RT-PCR及RACE法,分离、克隆鳜鱼β-肌动蛋白基因cDNA全序列,再用基因组步行法(Genome Walker)克隆鳜鱼β-肌动蛋白基因5′调控区。序列分析结果表明,鳜鱼β-肌动蛋白基因全长1897bp,其中5′-UTR长94bp,3′-UTR长675bp,编码区长1128bp,编码375个氨基酸。将所得序列与其它动物类群的β-肌动蛋白基因序列进行比较分析显示,鱼类、两栖类、鸟类、哺乳类等不同类群脊椎动物β-肌动蛋白氨基酸序列同源性均在96%以上,说明该基因在生物进化过程中高度保守。通过鳜鱼与其它脊椎动物β-肌动蛋白基因的核苷酸序列构建的进化树显示,脊椎动物β-肌动蛋白聚类成3个分支,鱼类β-肌动蛋白基因形成一个独立的分化群,说明鱼类β-肌动蛋白基因起源于一个共同祖先。克隆得到的鳜鱼β-肌动蛋白基因5'侧翼序列长1399bp,对其进行序列分析,在其起始密码字ATG上游200bp范围内发现含有CAATbox、CC(A/T)6GG(CArGbox)、TATA box对转录调控起重要作用的顺式元件,同时在侧翼区也发现含有GC box、MYOD、YY1、SP1、GATA等多个潜在调控元件。鳜鱼β-肌动蛋白基因5′侧翼序列的克隆成功,为今后转基因鳜鱼的研究工作奠定了基础。 展开更多
关键词 β-肌动蛋白基因 CDNA序列 5′调控区 克隆 鳜鱼
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利用5′锚定PCR技术分离枇杷微卫星标记 被引量:7
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作者 盛良明 薛华柏 +3 位作者 王化坤 徐春明 王三红 章镇 《江苏农业学报》 CSCD 北大核心 2007年第1期50-53,共4页
用5′锚定PCR技术分离出32个枇杷特异SSR位点,对其中适合设计引物的28个位点设计了相应的引物,并分别与对应的5′锚定的简并SSR引物配对,应用于5个枇杷品种的基因组PCR扩增。结果表明,27条引物在5个受试枇杷品种中有扩增产物,其中24条... 用5′锚定PCR技术分离出32个枇杷特异SSR位点,对其中适合设计引物的28个位点设计了相应的引物,并分别与对应的5′锚定的简并SSR引物配对,应用于5个枇杷品种的基因组PCR扩增。结果表明,27条引物在5个受试枇杷品种中有扩增产物,其中24条为可用引物,另外3条引物因为扩增产物不符合SSR标记的特征不能用作SSR标记的引物。 展开更多
关键词 枇杷 5’锚定PCR技术 微卫星标记
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