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In vitro effect of amoxicillin and clarithromycin on the 3' region of cagA gene in Helicobacter pylori isolates 被引量:5
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作者 Javier Andrés Bustamante-Rengifo Andrés Januer Matta +1 位作者 Alvaro Pazos Luis Eduardo Bravo 《World Journal of Gastroenterology》 SCIE CAS 2013年第36期6044-6054,共11页
AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric... AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric biopsies from 206 Colombian patients with dyspeptic symptoms from a high-risk area for gastric cancer were included as study material.Antimicrobial susceptibility was determined by the agar dilution method.Resistant isolates at baseline and in amoxicillin and clarithromycin serial dilutions were subjected to genotyping(cagA,vacA alleles s and m),Glu-Pro-Ile-Tyr-Ala(EPIYA)polymerase chain reaction and random amplified polymorphic DNA(RAPD).Images of the RAPD amplicons were analyzed by Gel-Pro Analyzer 4.5program.Cluster analyses was done using SPSS 15.0statistical package,where each of the fingerprint bands were denoted as variables.Dendrograms were designed by following Ward’s clustering method and the estimation of distances between each pair of H.pylori isolates was calculated with the squared Euclidean distance.RESULTS:Resistance rates were 4%for amoxicillin and 2.7%for clarithromycin with 2%double resistances.Genotyping evidenced a high prevalence of the genotype cagA-positive/vacA s1m1.The 3’region of cagA gene was successfully amplified in 92.3%(12/13)of the baseline resistant isolates and in 60%(36/60)of the resistant isolates growing in antibiotic dilutions.Upon observing the distribution of the number of EPIYA repetitions in each dilution with respect to baseline isolates,it was found that in 61.5%(8/13)of the baseline isolates,a change in the number of EPIYA repetitions lowered antibiotic pressure.The gain and loss of EPIYA motifs resulted in a diversity of H.pylori subclones after bacterial adjustment to changing conditions product of antibiotic pressure.RAPD PCR evidenced the close clonal relationship between baseline isolates and isolates growing in antibiotic dilutions.CONCLUSION:Antibiotic pressure does not induce loss of the cag pathogenicity island,but it can leadin most cases-to genetic rearrangements within the3’region cagA of the founding bacteria that can affect the level of tyrosine phosphorylation impacting on its cellular effects and lead to divergence of cagA-positive subclones. 展开更多
关键词 HELICOBACTER PYLORI Antimicrobial susceptibility cag pathogenicity island CAGA 3region Random amplified POLYMORPHIC DNA-polymerase chain reaction
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3D Geological Modeling with Multi-source Data Integration in Polymetallic Region:A Case Study of Luanchuan,Henan Province,China 被引量:1
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作者 Gongwen Wang~(1,2),Shouting Zhang~(1,2),Changhai Yan~3,Yaowu Song~3,Limei Wang~1 1.School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 2.State Key laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China 3.Henan Institute of Geological Survey,Zhengzhou 450007,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期166-167,共2页
The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luan... The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luanchuan,the case study area,southwestern Henan Province,is an important molybdenum-tungsten -lead-zinc polymetallic belt in China. 展开更多
关键词 3D GEOLOGICAL modeling MULTI-SOURCE data MINERAL exploration METALLOGENIC model virtual GEOLOGICAL section Luanchuan POLYMETALLIC region
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渤海湾盆地石臼坨凸起秦皇岛27-3大型油田发现与地质新认识 被引量:6
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作者 周家雄 徐春强 +4 位作者 杨海风 张宏国 张震 柳永军 张德龙 《中国海上油气》 CAS CSCD 北大核心 2024年第1期14-25,共12页
渤海湾盆地石臼坨凸起历经50余年勘探,在凸起高部位背斜区发现了3个浅层亿吨级大油田,而低部位斜坡区浅层由于构造圈闭不发育,勘探程度较低,近10年无规模性发现。随着渤海海域勘探程度提高,现已全面进入岩性勘探阶段,针对石臼坨凸起东... 渤海湾盆地石臼坨凸起历经50余年勘探,在凸起高部位背斜区发现了3个浅层亿吨级大油田,而低部位斜坡区浅层由于构造圈闭不发育,勘探程度较低,近10年无规模性发现。随着渤海海域勘探程度提高,现已全面进入岩性勘探阶段,针对石臼坨凸起东段顺向断裂斜坡区浅层油气运移、岩性圈闭刻画和油气成藏规律等展开了深入系统研究。研究认为:(1)研究区南北两侧被富生烃凹陷夹持,凸起边界大断层晚期强烈活动和陡坡带近源扇体普遍发育使凸起区成为规模性油气运聚的最终指向区;(2)凸起边界大断层在馆陶组开启系数最小,馆陶组含砾砂岩输导层是石臼坨凸起之上主要的油气横向运移通道;(3)馆陶组输导脊坡度和切脊断层组合控制顺向斜坡区油气的垂向输导,当坡度小于1°且断层长度大于2.50 km、成藏期断距大于40 m时斜坡区可产生规模性的油气垂向运移,突破顺向断裂斜坡区“过路不留”的传统认识;(4)在凸起斜坡区,与构造脊方向斜交的砂体有利于油气保存,同时,提出井约束谱蓝化整形高分辨率处理技术,实现了对斜坡区岩性圈闭有效刻画,优选出保存条件较好的斜向砂体开展钻探部署。基于上述新认识、新技术,2023年在石臼坨凸起东段顺向斜坡区成功评价了秦皇岛27-3亿吨级油田,实现了勘探老区浅层挖潜的重大突破,为渤海湾盆地高成熟探区持续油气发现提供了借鉴。 展开更多
关键词 秦皇岛27-3
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miR-15b-5p targeting amyloid precursor protein is involved in the anti-amyloid eflect of curcumin in swAPP695-HEK293 cells 被引量:3
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作者 Hong-Ying Liu Xian Fu +4 位作者 You-Fu Li Xian-Liang Li Zhen-Yu Ma Ying Zhang Qing-Chun Gao 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第9期1603-1609,共7页
Curcumin exerts a neuroprotective effect on Alzheimer’s disease;however,it is not known whether microRNAs are involved in this protective effect.This study was conducted using swAPP695-HEK293 cells as an Alzheimer’s... Curcumin exerts a neuroprotective effect on Alzheimer’s disease;however,it is not known whether microRNAs are involved in this protective effect.This study was conducted using swAPP695-HEK293 cells as an Alzheimer’s disease cell model.swAPP695-HEK293 cells were treated with 0,0.5,1,2,5,and 10μM curcumin for 24 hours.The changes in miR-15b-5p,miR-19a-3p,miR-195-5p,miR-101-3p,miR-216b-5p,miR-16-5p and miR-185-5p expression were assessed by real-time quantitative polymerase chain reaction.The mRNA and protein levels of amyloid precursor protein,amyloid-β40 and amyloid-β42 were evaluated by quantitative real-time polymerase chain reaction,western blot assays and enzyme-linked immunosorbent assays.swAPP695-HEK293 cells were transfected with miR-15b-5p mimic,or treated with 1μM curcumin 24 hours before miR-15b-5p inhibitor transfection.The effects of curcumin on amyloid precursor protein,amyloid-β40 and amyloid-β42 levels were evaluated by western blot assays and enzyme-linked immunosorbent assay.Luciferase assays were used to analyze the interaction between miR-15b-5p and the 3′-untranslated region of amyloid precursor protein.The results show that amyloid precursor protein and amyloid-βexpression were enhanced in swAPP695-HEK293 cells compared with HEK293 parental cells.Curcumin suppressed the expression of amyloid precursor protein and amyloid-βand up-regulated the expression of miR-15b-5p in swAPP695-HEK293 cells.In addition,we found a negative association of miR-15b-5p expression with amyloid precursor protein and amyloid-βlevels in the curcumin-treated cells.Luciferase assays revealed that miR-15b-5p impaired the luciferase activity of the plasmid harboring the 3′-untranslated region of amyloid precursor protein.These findings indicate that curcumin down-regulates the expression of amyloid precursor protein and amyloid-βin swAPP695-HEK293 cells,which was partially mediated by miR-15b-5p via targeting of the 3′-untranslated region of amyloid precursor protein. 展开更多
关键词 nerve REGENERATION Alzheimers disease natural plant drug CURCUMINOIDS miRNAs AMYLOID precursor protein amyloid-β 3′-untranslated region LUCIFERASE assays neurons neural REGENERATION
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Reprogramming somatic cells by fusion with embryonic stem cells does not cause silencing of the Dlk1-Dio3 region in mice
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作者 Nariman R Battulin Anna A Khabarova +3 位作者 Ul’yana A Boyarskikh Aleksey G Menzorov Maxim L Filipenko Oleg L Serov 《World Journal of Stem Cells》 SCIE CAS 2012年第8期87-93,共7页
AIM:To examine the imprinted Dlk1-Dio3 locus in pluripotent embryonic stem(ES)cell/fibroblast hybrid cells.METHODS:Gtl2,Rian,and Mirg mRNA expression in mouse pluripotent ES cell/fibroblast hybrid cells was examined b... AIM:To examine the imprinted Dlk1-Dio3 locus in pluripotent embryonic stem(ES)cell/fibroblast hybrid cells.METHODS:Gtl2,Rian,and Mirg mRNA expression in mouse pluripotent ES cell/fibroblast hybrid cells was examined by real-time reverse transcription-polymerase chain reaction.Pyrosequencing and bisulfate sequencing were used to determine the DNA methylation level of the Dlk1-Dio3 locus imprinting control region. RESULTS:The selected hybrid clones had a near-tetraploid karyotype and were highly pluripotent judging from their capacity to generate chimeric embryos and adult chimeras.Our data clearly demonstrate that Gtl2,Rian,and Mirg,which are imprinted genes within the Dlk1-Dio3 locus,are active in all examined ES cell/fibroblast hybrid clones.In spite of interclonal variability,the expression of the imprinted genes is comparable to that of ES cells and fibroblasts.Quantitative analysis of the DNA methylation status of the intergenic differentially methylated region(IG DMR)within the Dlk1-Dio3 locus by pyrosequencing and bisulfite sequencing clearly showed that the DNA methylation status of the imprinted region in the tested hybrid clones was comparable to that of both ES cells and fibroblasts.CONCLUSION:Reprogramming process in a hybrid cell system is achieved without marked alteration of the imprinted Dlk1-Dio3 locus. 展开更多
关键词 Cell FUSION EMBRYONIC stem cells REPROGRAMMING PLURIPOTENCY Imprinted Dlk1-Dio3 region DNA methylation
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Changes of heating and cooling degree days over China in response toglobal warming of 1.5℃, 2℃, 3℃ and 4℃ 被引量:8
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作者 SHI Ying ZHANG Dong-Feng +1 位作者 XU Ying ZHOU Bo-Tao 《Advances in Climate Change Research》 SCIE CSCD 2018年第3期192-200,共9页
Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over Ea... Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over East Asia using the regional climate model version 4.4 (RegCM4.4)driven by the global models of CSIRO-Mk3-6-0, EC-EARTH, HadGEM2-ES, and MPI-ESM-MR. Under global warming of 1.5℃, 2℃, 3℃,and 4℃, significant decrease of HDD can be found over China without considering population factor, with greater decrease over high elevationand high latitude regions, including the Tibetan Plateau, the northern part of Northeast China, and Northwest China; while population-weightedHDD increased in areas where population will increase in the future, such as Beijing, Tianjin, parts of southern Hebei, northern Shandong andHenan provinces. Similarly, the CDD projections with and without considering population factor are largely different. Specifically, withoutconsidering population, increase of CDD were observed over most parts of China except the Tibetan Plateau where the CDD remained zerobecause of the cold climate even under global warming; while considering population factor, the future CDD decreases in South China andincreases in North China, the Sichuan Basin, and the southeastern coastal areas, which is directly related to the population changes. The differentfuture changes of HDD and CDD when considering and disregarding the effects of population show that population distribution plays animportant role in energy consumption, which should be considered in future research. 展开更多
关键词 regionAL CLIMATE model Global WARMING of 1.5 2 3 and 4 Heating DEGREE DAYS Cooling DEGREE DAYS China
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3D Model Construction and Ecological Environment Investigation on a Regional Scale Using UAV Remote Sensing
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作者 Chao Chen Yankun Chen +7 位作者 Haohai Jin Li Chen Zhisong Liu Haozhe Sun Junchi Hong Haonan Wang Shiyu Fang Xin Zhang 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1655-1672,共18页
The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achiev... The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achieve using satellite remote sensing.Considering the convenient,facilitative,and flexible characteristics of UAV(unmanned air vehicle)remote sensing tech-nology,this study selects a campus as a typical research area and uses the Pegasus D2000 equipped with a D-MSPC2000 multi-spectral camera and a CAM3000 aerial camera to acquire oblique images and multi-spectral data.Using professional software,including Context Capture,ENVI,and ArcGIS,a 3D(three-dimensional)campus model,a digital orthophoto map,and multi-spectral remote sensing map drawing are realized,and the geometric accuracy of typical feature selection is evaluated.Based on a quantitative remote sensing model,the campus ecological environment assessment is performed from the perspectives of vegetation and water body.The results presented in this study could be of great significance to the scientific management and sustainable development of regional natural resources. 展开更多
关键词 Unmanned air vehicle multi-spectral camera oblique photography 3D model construction ecological environment investigation regional scale
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血清金属蛋白酶组织抑制剂3和性别决定区Y框蛋白2在2型糖尿病肾损伤早期诊断中的临床应用
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作者 张洪利 王海成 +2 位作者 李华 未瑞超 曾玲 《临床肾脏病杂志》 2024年第7期529-535,共7页
目的探究血清金属蛋白酶组织抑制剂3(tissue inhibitors of metalloproteinases 3,TIMP3)和性别决定区Y框蛋白2(transcription factor determining region Y box protein 2,SOX2)对2型糖尿病(type 2 diabetes mellitus,T2DM)肾损伤的早... 目的探究血清金属蛋白酶组织抑制剂3(tissue inhibitors of metalloproteinases 3,TIMP3)和性别决定区Y框蛋白2(transcription factor determining region Y box protein 2,SOX2)对2型糖尿病(type 2 diabetes mellitus,T2DM)肾损伤的早期诊断。方法选取2022年4月至2023年4月在华北石油管理局总医院就诊的102例T2DM患者为研究对象,根据24 h尿蛋白排泄率(uri-nary albumin excretion rate,UAER)将T2DM患者分为肾损伤组(n=40)和无肾损伤组(n=62),另选取同期在华北石油管理局总医院行体检的健康者50名为对照组。酶联免疫吸附法测定所有受试者血清TIMP3、SOX2水平;比较3组受试者一般资料、糖化血红蛋白(hemoglobin A1c,HbA1c)、UAER、血肌酐(serum creatinine,Scr)、估算肾小球滤过率(estimated glomerular filtration rate,eGFR)、血清TIMP3、SOX2水平;Pearson相关性分析血清TIMP3与SOX2及两者与HbA1c、UAER、Scr、eGFR之间的关系;受试者工作特征曲线(receiver operating characteristic curve,ROC)分析血清TIMP3、SOX2对T2DM患者肾损伤的诊断价值。结果T2DM患者血清TIMP3[(0.68±0.17)μg/L比(1.35±0.35)μg/L]及eGFR[(105.99±20.56)mL·min^(-1)·(1.73 m^(2))比(133.15±26.18)mL·min^(-1)·(1.73 m^(2))^(-1)]显著低于对照组(P<0.05),且肾损伤患者血清TIMP3[(0.47±0.11)μg/L比(0.82±0.21)^(-1)μg/L]及eGFR[(74.69±10.22)mL·min^(-1)·(1.73 m^(2))比(126.18±27.23)mL·min^(-1)·(1.73 m^(2))^(-1)]显著低于无肾损伤患者(P<0.05);血清SOX2[(8.91±1.82)kU/L比(5.15±1.31)kU/L]及HbA1c[(8.80±1.55)%比(5.52±0.83)%]、UAER[(70.13±18.06)mg/24 h比(13.22±3.61)mg/24 h]、Scr[(82.14±15.23)µmol/L比(53.19±5.62)µmol/L]显著高于对照组(P<0.05),且肾损伤患者血清SOX2[(10.81±2.13)kU/L比(5.15±1.31)kU/L]及UAER[(156.83±40.29)mg/24 h比(13.22±3.61)mg/24 h]、Scr[(113.77±13.58)µmol/L比(53.19±5.62)µmol/L]显著高于无肾损伤患者(P<0.05)。Pearson相关性分析结果显示,TIMP3与UAER、Scr、HbA1c呈显著负相关(P<0.05),与eGFR呈显著正相关(P<0.05);SOX2与UAER、Scr、HbA1c呈显著正相关(P<0.05),与eGFR呈显著负相关(P<0.05);血清TIMP3与SOX2呈显著负相关(r=-0.590,P<0.05)。ROC结果显示,血清TIMP3联合SOX2诊断T2DM患者肾损伤的敏感度和特异度分别为95.0%、85.3%,显著高于TIMP3、SOX2单独测定。结论T2DM肾损伤患者血清TIMP3水平显著降低,SOX2水平显著升高,且两者与T2DM患者肾损伤密切相关,可用于T2DM患者肾损伤早期诊断。 展开更多
关键词 金属蛋白酶组织抑制剂3 2 2尿
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Analysis of the 3' Variable Region of Cytotoxin-Associated Gene A (<i>cagA</i>) in <i>Helicobacter pylori</i>Isolates in China
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作者 Boqing Li Donglong Du +3 位作者 Wanju Sun Qizhi Cao Zhen Zhang Zhenzhen Du 《Pharmacology & Pharmacy》 2013年第5期13-18,共6页
Infection by the bacterium Helicobacter pylori is a putative cause of various gastric disorders, including gastric adenocarcinoma. Incident rates are associated with variants of the H. pylori virulence factor cytotoxi... Infection by the bacterium Helicobacter pylori is a putative cause of various gastric disorders, including gastric adenocarcinoma. Incident rates are associated with variants of the H. pylori virulence factor cytotoxin-associated gene A protein (CagA), encoded by the gene cagA. However, these variants have not been characterized in China, where gastric cancer is common. We investigated the diversity of CagA variants in H. pylori strains isolated from a Chinese population. The 3' variable region of cagA genes from 66 clinical isolates in China were amplified by polymerase chain reaction, sequenced, aligned, and analyzed. All 66 H. pylori strains were CagA-positive, of which 93.9% were East Asian type and the tyrosine phosphorylation motifs (TPMs) were EPIYA-ABD. The remainder was Western type, in which TPMs were EPIYA-ABC. Interestingly, two of sixty-two strains (3.2%) of the East Asian type were mutated into ESIYA-B, whereas all four Western type (100%) strains were mutated into EPIYT-B. Both of the two strains with Western-type CagA obtained from gastric cancer patients contained a distinguished mutation on the first residue following the EPIYA site in the EPIYA-A motif. The predominant CagA type in these H. pylori strains isolated from Chinese patients in China was East Asian, with TPMs EPIYA-ABD, and there existed mutations in both the East Asian and Western type CagA. 展开更多
关键词 HELICOBACTER pylori CAGA 3' Variable region China GASTRITIS Gastric Cancer
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The cumulative analgesic effect of repeated electroacupuncture involves synaptic remodeling in the hippocampal CA3 region 被引量:5
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作者 Qiulinq Xu Tao Liu +4 位作者 Shuping Chen Yonghui Gao Junying Wang Lina Qiao Junling Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第18期1378-1385,共8页
In the present study, we examined the analgesic effect of repeated electroacupuncture at bilateral Zusanfi (ST36) and Yanglingquan (GB34) once a day for 14 consecutive days in a rat model of chronic sciatic nerve ... In the present study, we examined the analgesic effect of repeated electroacupuncture at bilateral Zusanfi (ST36) and Yanglingquan (GB34) once a day for 14 consecutive days in a rat model of chronic sciatic nerve constriction injury-induced neuropathic pain. In addition, concomitant changes in calcium/calmodulin-dependent protein kinase II expression and synaptic ultrastructure of neurons in the hippocampal CA3 region were examined. The thermal pain threshold (paw withdrawal latency) was increased significantly in both groups at 2 weeks after electroacupuncture intervention compared with 2 days of electroacupuncture. In ovariectomized rats with chronic constriction injury, the analgesic effect was significantly reduced. Electroacupuncture for 2 weeks significantly diminished the injury-induced increase in synaptJc cleft width and thinning of the postsynaptJc density, and it significantly suppressed the down-regulation of intracellular calcium/ calmodulin-dependent protein kinase II expression in the hippocampal CA3 region. Repeated electroacupuncture intervention had a cumulative analgesic effect on injury-induced neuropathic pain reactions, and it led to synaptic remodeling of hippocampal neurons and upregulated calcium/calmodulin-dependent protein kJnase II expression in the hippocampal CA3 region. 展开更多
关键词 chronic neuropathic pain acupuncture analgesia cumulative effect synaptic plasticity hippocampal CA3 region calcium/calmodulin-dependent protein kinase II NEUROBIOLOGY ELECTROACUPUNCTURE neural regeneration
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Form confers function:Case of the 3'X region of the hepatitis C virus genome
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作者 Mariola Dutkiewicz Jerzy Ciesiolka 《World Journal of Gastroenterology》 SCIE CAS 2018年第30期3374-3383,共10页
At the 3' end of genomic hepatitis C virus(HCV) RNA there is a highly conserved untranslated region,the 3'X-tail,which forms part of the 3'UTR.This region plays key functions in regulation of critical proc... At the 3' end of genomic hepatitis C virus(HCV) RNA there is a highly conserved untranslated region,the 3'X-tail,which forms part of the 3'UTR.This region plays key functions in regulation of critical processes of the viral life cycle.The 3'X region is essential for viral replication and infectivity.It is also responsible for regulation of switching between translation and transcription of the viral RNA.There is some evidence indicating the contribution of the 3'X region to the translation efficiency of the viral polyprotein and to the encapsidation process.Several different secondary structure models of the 3'X region,based on computer predictions and experimental structure probing,have been proposed.It is likely that the 3'X region adopts more than one structural form in infected cells and that a specific equilibrium between the various forms regulates several aspects of the viral life cycle.The most intriguing explanations of the structural heterogeneity problem of the 3'X region came with the discovery of its involvement in long-range RNA-RNA interactions and the potential for homodimer formation.This article summarizes current knowledge on the structure and function of the 3'X region of hepatitis C genomic RNA,reviews previous opinions,presents new hypotheses and summarizes the questions that still remain unanswered. 展开更多
关键词 HEPATITIS C virus 3’UTR 3’X-tail 3’X region 3’X RNA RNA structure
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Evolutionary relationship of 5′-untranslated regions among Thai dengue-3 viruses,Bangkok isolates,during 24 year-evolution
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作者 Watcharee Attatippaholkun Panyupa Pankhong +1 位作者 Ananda Nisalak Siripen Kalayanarooj 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第3期176-184,共9页
Objective:To study evolutionary relationship of the 5'untranslated regions(5'UTRs) in low passage dengue3 viruses(DEN3) isolated from hospitalized children with different clinical manifestations in Bangkok dur... Objective:To study evolutionary relationship of the 5'untranslated regions(5'UTRs) in low passage dengue3 viruses(DEN3) isolated from hospitalized children with different clinical manifestations in Bangkok during 24 year-evolution(1977-2000) comparing to the DEN3prototype(H87).Methods:The 5'UTRs of these Thai DEN3 and the H87 prototype were amplified by RT-PCR and sequenced.Their multiple sequence alignments were done by Codon Code Aligner v 4.0.4 software and their RNA secondary structures were predicted by MFOLD software.Replication of five Thai DEN3 candidates comparing to the 1187 prototype were done in human(HepG2) and the mosquito(C6/36) cell lines.Results:Among these Thai DEN3,the completely identical sequences of their first 89 nucleotides,their high-order secondary structure of 5'UTRs and three SNPs including the predominant C90 T,and two minor SNPs including A109 G and A112 G were found.The C90 T of Thai DEN3.Bangkok isolates was shown predominantly before 1977.Five Thai DEN3 candidates with the predominant C90 T were shown to replicate in human(HepG2) and the mosquito(C6/36) cell lines better than the H87 prototype.However,their highly conserved sequences as well as SNPs of the 5'UTR did not appear to correlate with their disease severity in human.Conclusions:Our findings highlighted evolutionary relationship of the completely identical 89 nucleotide sequence,the high-order secondary structure and the predominant C90 T of the 5'UTR of these Thai DEN3 during 24 year-evolution further suggesting to be their genetic markers and magic targets for future research on antiviral therapy as well as vaccine approaches of Thai DEN3. 展开更多
关键词 THAI dengue-3 viruses Evolutionary relationship 5untranslated regions 24 Year-evolution
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基于免疫组库测序的肝硬化典型证候患者外周血T细胞受体β链CDR3多样性分析
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作者 王佳 胡宇婷 +3 位作者 龚跃峰 朱健 苏式兵 陆奕宇 《世界科学技术-中医药现代化》 CSCD 北大核心 2024年第7期1916-1924,共9页
目的 本研究通过免疫组库测序,分析肝硬化不同典型证候患者外周血TCR β链CDR3的多样性,探讨肝硬化证候的物质基础及其规律。方法 20例肝硬化患者为病例组,包括肝胆湿热(LGHD)、肝郁脾虚(LDSD)、肝肾阴虚(LKYD)3种证型,10例健康患者为... 目的 本研究通过免疫组库测序,分析肝硬化不同典型证候患者外周血TCR β链CDR3的多样性,探讨肝硬化证候的物质基础及其规律。方法 20例肝硬化患者为病例组,包括肝胆湿热(LGHD)、肝郁脾虚(LDSD)、肝肾阴虚(LKYD)3种证型,10例健康患者为正常对照组。从外周血样品中提取DNA,对TCRβ链CDR3进行多重PCR扩增,然后对产物进行高通量测序,分析其TCR β链CDR3的多样性。结果 肝硬化证候LDSD的CDR3独有nt序列数与CDR3独有aa序列数均少于LKYD(P<0.05);LGHD和LKYD的Clonality、Pielous、Shannon.Index和DE50具有显著性差异(P<0.05);3种证型的V和J区基因中多个片段使用频率及V-J基因重组有显著性差异:在LGHD和LDSD中,TRBV21-1、TRBV12-4、TRBV11-1亚型及7对V-J重组有统计学差异(P<0.05);在LGHD和LKYD中,TRBV10-2、TRBV7-6、TRBV5-8亚型及30对V-J重组有统计学差异(P<0.05);在LDSD和LKYD中,TRBJ1-5亚型及18对V-J重组有统计学差异(P<0.05)。结论本研究通过挖掘肝硬化不同证候的免疫学特征,发现肝硬化证候TCR CDR3的多样性具有显著差异且符合由实向虚的证型变化规律,为寻找“病证结合”“辨证论治”的客观依据提供新的支撑,以期发现肝硬化不同证候人群适应性免疫基因重排的表达差异和特异性标记。 展开更多
关键词 T 互补决定区3
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宝麦3号小麦新品种区域试验结果及栽培技术
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作者 蔺建章 《河北科技师范学院学报》 CAS 2005年第2期50-52,共3页
2002~2003年进行了小麦新品种宝麦3号的区域试验、生产试验、品质鉴定及栽培技术研究.结果表明:宝麦3号小麦2002年度区域试验比对照品种京冬8号增产2.21%,差异不显著;2003年度区域试验比对照增产5.76%,差异达极显著;2003年度生产试验... 2002~2003年进行了小麦新品种宝麦3号的区域试验、生产试验、品质鉴定及栽培技术研究.结果表明:宝麦3号小麦2002年度区域试验比对照品种京冬8号增产2.21%,差异不显著;2003年度区域试验比对照增产5.76%,差异达极显著;2003年度生产试验比对照增产8.29%.宝麦3号适应性广泛,具有抗寒、抗旱、耐病等多种抗性,可作为冀中北地区良好的接班品种. 展开更多
关键词 2002~2003 2003年度 2002 8
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0~3岁婴幼儿托育教养人员生存状态的地区差异及影响因素分析
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作者 秦旭芳 臧天品 黄思芸 《重庆第二师范学院学报》 2024年第4期74-81,128,共9页
关注0~3岁婴幼儿托育教养人员的生存状态有利于其专业成长和队伍稳定。通过对东北、华东、西部三个地区666名托育教养人员生存状态的实证调查,发现托育教养人员生存状态总体水平中等偏上且存在地区差异,政府保障是影响东北地区托育教养... 关注0~3岁婴幼儿托育教养人员的生存状态有利于其专业成长和队伍稳定。通过对东北、华东、西部三个地区666名托育教养人员生存状态的实证调查,发现托育教养人员生存状态总体水平中等偏上且存在地区差异,政府保障是影响东北地区托育教养人员生存状态的关键因素,机构管理是影响华东地区托育教养人员生存状态的潜在因素,个体主观是影响西部地区托育教养人员生存状态的驱动因素。基于调查结果,提出改善托育教养人员生存状态的建议。 展开更多
关键词 0~3岁婴幼儿
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Histone H3K27me3 methylation regulates the expression of secreted proteins distributed at fast-evolving regions through transcriptional repression of transposable elements 被引量:1
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作者 XIE Jia-hui TANG Wei +4 位作者 LU Guo-dong HONG Yong-he ZHONG Zhen-hui WANG Zong-hua ZHENG Hua-kun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第10期3059-3068,共10页
The fine-tuned expression dynamics of the effector genes are pivotal for the transition from vegetative growth to host colonization of pathogenic filamentous fungi.However,mechanisms underlying the dynamic regulation ... The fine-tuned expression dynamics of the effector genes are pivotal for the transition from vegetative growth to host colonization of pathogenic filamentous fungi.However,mechanisms underlying the dynamic regulation of these genes remain largely unknown.Here,through comparative transcriptome and chromatin immunoprecipitation sequencing(ChIP-seq)analyses of the methyltransferase PoKmt6 in rice blast fungus Pyricularia oryzae(syn.Magnaporthe oryzae),we found that PoKmt6-mediated H3K27me3 deposition was enriched mainly at fast-evolving regions and contributed to the silencing of a subset of secreted proteins(SP)and transposable element(TE)families during the vegetative growth of P.oryzae.Intriguingly,we observed that a group of SP genes,which were depleted of H3K27me3 modification,could also be silenced via the H3K27me3-mediated repression of the nearby TEs.In conclusion,our results indicate that H3K27me3 modification mediated by PoKmt6 regulates the expression of some SP genes in fast-evolving regions through the suppression of nearby TEs. 展开更多
关键词 secreted protein transposable elements fast-evolving regions H3K27me3
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长顺绿壳蛋鸡GRIN1基因3′非翻译区的多态性及其与蛋壳品质的关联性
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作者 罗华伦 王春源 +2 位作者 吴燕 向进 张依裕 《云南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期56-63,共8页
【目的】探索长顺绿壳蛋鸡GRIN1基因3′非翻译区(untranslated region,UTR)多态性对蛋壳品质的影响。【方法】选择185只健康蛋鸡,测定其第45周龄产蛋的蛋质量、蛋形指数、蛋壳强度、蛋壳厚度和蛋壳质量5个指标;使用NCBI和PrimerPremier ... 【目的】探索长顺绿壳蛋鸡GRIN1基因3′非翻译区(untranslated region,UTR)多态性对蛋壳品质的影响。【方法】选择185只健康蛋鸡,测定其第45周龄产蛋的蛋质量、蛋形指数、蛋壳强度、蛋壳厚度和蛋壳质量5个指标;使用NCBI和PrimerPremier 3.0设计引物,采用正向测序法筛选GRIN1基因在3′UTR区域的SNP位点。【结果】GRIN1基因的3′UTR检测到4个SNP位点:g.30871C>T、g.31017A>G、g.31158A>C和g.31166G>C,其中仅g.31158A>C和g.31166G>C之间存在强连锁不平衡,且g.30871C>T和g.31017A>G都极显著偏离哈代—温伯格平衡(P<0.01)。g.31017A>G与蛋壳品质的关联分析中,GG基因型的蛋质量显著高于AA基因型(P<0.05)。4个SNP位点共产生5个单倍型(H1、H2、H3、H4、H5)和8个双倍型(H1H1、H1H2、H1H3、H2H2、H2H3、H2H4、H3H5、H4H4),双倍型H3H5的蛋质量显著高于双倍型H2H2和H2H3(P<0.05),双倍型H3H5的蛋壳质量显著高于双倍型H2H2(P<0.05),其他双倍型指标间的差异未达到显著水平(P>0.05)。【结论】长顺绿壳蛋鸡GRIN1基因与蛋壳品质存在显著关联;g.31017A>G对蛋壳品质有显著影响,能够作为改善蛋壳品质的分子标记位点参考。 展开更多
关键词 绿 GRIN1 3′非翻译区 SNP
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A reduced computational load protein coding predictor using equivalent amino acid sequence of DNA string with period-3 based time and frequency domain analysis 被引量:1
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作者 Jayakishan K. Meher Gananath N. Dash +1 位作者 Pramod Kumar Meher Mukesh Kumar Raval 《American Journal of Molecular Biology》 2011年第2期79-86,共8页
Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein codi... Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein coding regions in DNA sequences is based on the period-3 property exhibited by nucleotides in exons. Several approaches based on signal processing tools and numerical representations have been applied to solve this problem, trying to achieve more accurate predictions. This paper presents a new indicator sequence based on amino acid sequence, called as aminoacid indicator sequence, derived from DNA string that uses the existing signal processing based time-domain and frequency domain methods to predict these regions within the billions long DNA sequence of eukaryotic cells which reduces the computational load by one-third. It is known that each triplet of bases, called as codon, instructs the cell machinery to synthesize an amino acid. The codon sequence therefore uniquely identifies an amino acid sequence which defines a protein. Thus the protein coding region is attributed by the codons in amino acid sequence. This property is used for detection of period-3 regions using amino acid sequence. Physico-chemical properties of amino acids are used for numerical representation. Various accuracy measures such as exonic peaks, discriminating factor, sensitivity, specificity, miss rate, wrong rate and approximate correlation are used to demonstrate the efficacy of the proposed predictor. The proposed method is validated on various organisms using the standard data-set HMR195, Burset and Guigo and KEGG. The simulation result shows that the proposed method is an effective approach for protein coding prediction. 展开更多
关键词 GENOMICS Bioinformatics CODON Coding region Amino Acid SEQUENCE Fourier Transform Antinotch Filter Periodicity-3 Indicator SEQUENCE
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0-3岁婴幼儿阅读发展问卷调查研究中的方法问题——基于中国知识网库文献的内容分析
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作者 钱高垠 潘俊林 《图书馆研究与工作》 2024年第1期37-45,63,共10页
问卷调查是国内0—3岁婴幼儿阅读发展的培育和支持研究中最常采用的方式。文章采用内容分析的方法,对中国知网(CNKI)数据库中的10篇已发表的论文在理论基础、设计、分析和解释等方面进行了分析,旨在总结问卷调查近20年来在促进0—3岁婴... 问卷调查是国内0—3岁婴幼儿阅读发展的培育和支持研究中最常采用的方式。文章采用内容分析的方法,对中国知网(CNKI)数据库中的10篇已发表的论文在理论基础、设计、分析和解释等方面进行了分析,旨在总结问卷调查近20年来在促进0—3岁婴幼儿阅读发展的研究成果,并找出这些研究项目的潜在问题:研究者很少使用理论框架来证明研究问题的合理性;大多数自制设计的调查工具没有建立其有效性和可靠性;没有遵循严格的数据收集程序,并且在分析中没有对结果进行交叉验证。笔者还注意到,目前大部分研究重点都集中在发达的城市地区,如何运用知识基金的理论关注农村,特别是欠发达地区0—3岁婴幼儿的阅读发展,具有迫切的现实意义。 展开更多
关键词 0—3岁婴幼儿 广
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邯郸地区2017—2021年PM_(2.5)和O_(3)污染特征
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作者 牛红亚 金妞 +4 位作者 胡塔峰 胡伟 王硕 史沥介 王金喜 《中国环境监测》 CAS CSCD 北大核心 2024年第3期60-70,共11页
利用实时监测数据分析2017—2021年邯郸市及周边区县PM_(2.5)和O_(3)污染特征。研究发现:2017—2021年各地区PM_(2.5)年均质量浓度持续降低,轻度及轻度以上污染逐渐减少;2017—2019年O_(3)污染加剧,2020年起O_(3)年均质量浓度逐年下降,... 利用实时监测数据分析2017—2021年邯郸市及周边区县PM_(2.5)和O_(3)污染特征。研究发现:2017—2021年各地区PM_(2.5)年均质量浓度持续降低,轻度及轻度以上污染逐渐减少;2017—2019年O_(3)污染加剧,2020年起O_(3)年均质量浓度逐年下降,污染天不断减少。PM_(2.5)和O_(3)-8 h分别在1月(平均浓度为127.3μg/m^(3),平均超标22d)和6月(平均浓度为233.4μg/m^(3),平均超标22 d)污染最严重。结合气象参数分析来看,PM_(2.5)与温度、风速和降水量呈显著负相关,与相对湿度呈显著正相关;O_(3)-8 h与温度呈显著正相关,而与风速、湿度和降水量的相关性较弱。后向轨迹和潜在源分析表明:邯郸地区PM_(2.5)典型污染月受山西省中部地区污染传输影响最大,O_(3)典型污染月受河南省东部污染传输影响最大。 展开更多
关键词 PM_(2.5) O_(3)
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