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21.
【目的】检测深圳地区环境水体和人群的诺如病毒(No Vs),探讨其是否在两者之间循环传播。【方法】2014年3月至2015年2月检测24份深圳茅洲河河水标本和287份腹泻患者粪便标本。河水标本经过混合纤维素酯膜和PEG法二次浓缩后提取核酸,粪便标本无需浓缩,稀释离心后直接提取核酸。应用实时荧光逆转录PCR初步分型,RT-PCR扩增ORF2保守区域衣壳蛋白(VP1)基因后测序确定亚型、分析不同来源病毒的同源性;同时建立基因进化树,进一步分析不同来源No Vs的亲缘关系。【结果】在河水标本和腹泻患者粪便标本中,No Vs阳性率分别为23.1%和17.4%,其中上下游河水标本阳性率分别为8.3%和41.7%,河水中No VGI型和No VGII型的阳性率为16.7%和8.3%。扩增阳性样本发现茅洲河水中检出No V主要是GI.6型,其次是GII.4 Sydney_2012型,而从腹泻胃肠炎患者粪便标本中检出No Vs主要是No VGII.4Sydney_2012型和少量的GII.3型。同时期水体和人群粪便标本来源的No VGII.4 Sydney_2012型VP1基因相似性98.2%–100.0%。【结论】No VGII.4 Sydney_2012型是深圳地区主要的流行株。No Vs在环境水体和人群中于某种程度上存在循环传播。  相似文献   
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采用硅胶柱、反相硅胶柱和凝胶柱等色谱技术和重结晶进行分离纯化,从一株分离自南海沉积物的海洋真菌帚状弯孢聚壳Eutypella scoparia的液体发酵提取物中分离得到6个化合物。通过分析波谱数据和与文献比对,化合物1-6分别被鉴定为:(3S,3aR,7aS)-3a,4,5,7a-tetrahydro-3,6-dimethylbenzofuran-2(3H)-one (1),rel-(3S,6S,7R,10R)-7,10-epoxy-3,7,11- trimethyldodec-1-ene-3,6,11-triol (2),euphorbol (3),tuberoside (4),phenochalasin B (5),尿嘧啶(6)。生物活性测试结果显示细胞松弛素类化合物5对MCF-7、NCI-H460和SF-268三种肿瘤细胞株均具有显著的抗肿瘤活性,其IC50分别为0.022μmol/L、0.073μmol/L和0.059μmol/L。  相似文献   
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Previous research showed that microRNA-612 (miR-612) has inhibitory effects on cell proliferation, migration, invasion, and metastasis of hepatocellular carcinoma (HCC). AKT2 was confirmed to be a direct target of miR-612, through which the epithelial–mesenchymal transition (EMT) and metastasis of HCC were inhibited. Our present findings reveal that miR-612 is able to suppress the stemness of HCC by reducing the number and size of tumorspheres as well as clone formation in soft agar, and to relieve drug resistance to cisplatin and 5-fluorouracil. In addition, miR-612 hampered the capacity of tumorigenesis in NOD/SCID mice and redistributed the tumor invasive frontier of miR-612-modulating cells. Finally, our findings suggest that Wnt/β-catenin signaling is required in the regulation of EMT-associated stem cell-like traits by miR-612.  相似文献   
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A competitive enzyme-linked immunosorbent assay (ELISA) for detection of a type I collagen fragment generated by matrix metalloproteinases (MMP) -2, -9 and -13, was developed (CO1-764 or C1M). The biomarker was evaluated in two preclinical rat models of liver fibrosis: bile duct ligation (BDL) and carbon tetra chloride (CCL4)-treated rats. The assay was further evaluated in a clinical study of prostate-, lung- and breast-cancer patients stratified according to skeletal metastases. A technically robust ELISA assay specific for a MMP-2, -9 and -13 neo-epitope was produced and seen to be statistically elevated in BDL rats compared to baseline levels as well as significantly elevated in CCL4 rats stratified according to the amount of total collagen in the livers. CO1-764 levels also correlated significantly with total liver collagen and type I collagen mRNA expression in the livers. Finally, the CO1-764 marker was not correlated with skeletal involvement or number of bone metastases. This ELISA has the potential to assess the degree of liver fibrosis in a non-invasive manner.  相似文献   
27.
利用TrnL-F序列探讨苎麻属植物的系统发育关系   总被引:1,自引:0,他引:1  
目的:探讨苎麻属植物的系统发育关系。方法:对10个种和8个变种苎麻属植物的TrnL-F序列进行PCR扩增和T/A克隆产物序列测定;选取雾水葛属的植物作为参考外类群,同样也测定其TrnL-F全序列;根据TrnL-F区碱基序列的差异计算种间的遗传距离,采用UPGMA法进行系统发育分析并得到系统发育树。结果:野线麻、福州苎麻、赤麻、悬铃叶苎麻、序叶苎麻、白面苎麻、束序苎麻、密球苎麻、疏毛水苎麻、圆叶水苎麻、灰绿水苎麻和糙叶水苎麻聚成一支;帚序苎麻、黔桂苎麻、苎麻、微绿苎麻、贴毛苎麻和青叶苎麻聚为另一支;雾水葛单独聚成一类,与苎麻属的其他种在一级分支中即分开,与其他种的亲缘关系较远。结论:帚序苎麻组和苎麻组植物具有较近的亲缘关系。  相似文献   
28.
The endophytic fungus Nodulisporium sylviforme produces taxol, a diterpene alkaloid compound that has unique anti-neoplastic activity. In this study, suppression subtractive hybridization was performed to identify genes in N. sylviforme that were involved in the up-regulation of taxol production. A total of 91 clones represented the differentially expressed genes were selected based on reverse blotting results. These clones were then sequenced and analyzed using BLAST-X comparisons that revealed that about 37.8% of the ESTs were homologous to 17 different proteins with known function, 20.7% were homologous to nine hypothetical proteins and the remaining 41.5% had no identifiable homology; these may be novel genes. Two enzymatic genes involved in taxol production were found. The data presented in this study provide the first primary overview of a set of genes that are differentially expressed in N. sylviforme during taxol biosynthesis and form a solid foundation for the construction of high taxol-yielding genetically engineered strains.  相似文献   
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大叶苎麻组(Sect.Duretia)是荨麻科苎麻属(Boehmeria)的一个种类比较多的组,目前对该组植物的系统发育还不清楚.本研究测定了其中9种4变种的核糖体DNA的ITS序列.ITS平均长度约687 bp.选取冷水花属作为外类群,根据ITS序列的差异计算出种间遗传距离.分别采用最简约法和邻接法进行系统发育分析.细野麻(Boehmeria gracilis)、赤麻(B.silvestrii)、野线麻(B.japonica)和疏毛水苎麻(B.pilosiuacula)、束序苎麻(B.siamensis)亲缘关系较近聚成一支,自展支持率为76%(MP)和89%(NJ);密球苎麻(B.densiglomerata)、长序苎麻(B.dolichostachya)、灰绿水苎麻(B.macrophylla var.canescens)、糙叶水苎麻(B.macrophylla var.scabrella)、圆叶水苎麻(B.macrophylla vat.rotundifolia)和海岛苎麻(B. formosana)、福州苎麻(B.formosana var.stricta)则聚为另一支,自展支持率为74%(MP)和94%(NJ);歧序苎麻(B.polystachya)单独为一支,与大叶苎麻组的其他种在一级分支中就分开,和其他种亲缘关系较远.  相似文献   
30.
为建立沙葱萤叶甲Gauleruca daurica成虫对蜕皮激素(20-hydroxyecdysone, 20E)响应的转录组数据库,挖掘对20E响应的基因以及代谢和信号通路,并在转录组水平探讨20E调控生殖滞育的分子机制,本研究采用Illumina HiSeqTM4000高通量测序平台对20E及二甲基亚砜(dimethyl sulfoxide, DMSO)处理后的沙葱萤叶甲成虫进行了转录组测序,共获得80 313个unigene;与阴性对照DMSO相比,共获得201个差异表达基因,其中106个上调、95个下调。GO和KEGG富集分析表明,多数差异表达功能基因富集于各种代谢通路,其中核黄素代谢(riboflavin metabolism)、溶酶体(lysosome)和泛酸与乙酰辅酶A合成(pantothenate and CoA biosynthesis)通路显著富集(q<0.05)。结果表明,20E可能通过影响多种代谢通路调控沙葱萤叶甲的生殖滞育。  相似文献   
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