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91.
目的 评估ITS2(internal transcribed spacer 2)序列作为DNA条码鉴定菊科藏药材及其近缘物种的能力。方法 于西藏自治区等地采集菊科植物样本50份,共26个物种,分布于8个属,它们大部分可以用作藏药材。采用遗传距离比较法和系统聚类树法评估ITS2序列的鉴定能力。首先,采用试剂盒法提取基因组DNA,PCR扩增ITS2序列并双向测序。从GenBank数据库中下载26种菊科植物的rDNA序列(包含完整的ITS2区域)。上述序列经过CodonCode Aligner v.9.0.1软件拼接后,用MEGA 11.0.10软件构建NJ系统聚类树,用TaxonGap v.2.4.1软件分析种内和种间变异。结果 采用系统聚类树法和遗传距离比较法,ITS2序列可以从3种蒿属植物中鉴别出大籽蒿(Artemisia sieversiana),6种紫菀属植物中鉴别出灰枝紫菀(Aster poliothamnus),2种垂头菊属植物中鉴别出车前状垂头菊(Cremanthodium ellisii)和条叶垂头菊(Cremanthodium lineare),3种风毛菊属植物中鉴别出美丽风毛菊(Saussurea superba),并且可以将小苦荬属的中华小苦荬(Ixeridium chinense)和窄叶小苦荬(Ixeridium gramineum)区分开,可以将毛香火绒草(Leontopodium stracheyi)、三角叶蟹甲草(Parasenecio deltophyllus)与其他物种区分开。ITS2序列可以成功地从26个菊科物种中鉴别出9个物种,鉴定效率为34.6%。结论 ITS2序列可以用于快速、准确地识别和鉴定部分菊科藏药材。 相似文献
92.
吴晓莉 《临床心身疾病杂志》2013,19(3):265-266
目的探讨大学生人际信任与主观幸福感的相关性。方法对176名大学生采用人际信任量表和总体幸福感量表进行测评分析。结果大学生人际信任量表总分与总体幸福感量表总分呈显著正相关(P〈0.01),与抑郁心境、对情感与行为的控制、焦虑因子分呈显著负相关(P〈O.05或0.01)。结论大学生的人际信任与主观幸福感有密切联系,人际关系困扰越严重的大学生,其主观幸福感程度越低。 相似文献
93.
M. Ruiz‐Estvez F. J. Ruiz‐Ruano J. Cabrero M. Bakkali F. Perfectti M. D. Lpez‐Len J. P. M. Camacho 《Insect molecular biology》2015,24(3):319-330
We analyse intragenomic variation of the ITS2 internal transcribed spacer of ribosomal DNA (rDNA) in the grasshopper Eyprepocnemis plorans, by means of tagged PCR 454 amplicon sequencing performed on both genomic DNA (gDNA) and RNA‐derived complementary DNA (cDNA), using part of the ITS2 flanking coding regions (5.8S and 28S rDNA) as an internal control for sequencing errors. Six different ITS2 haplotypes (i.e. variants for at least one nucleotide in the complete ITS2 sequence) were found in a single population, one of them (Hap4) being specific to a supernumerary (B) chromosome. The analysis of both gDNA and cDNA from the same individuals provided an estimate of the expression efficiency of the different haplotypes. We found random expression (i.e. about similar recovery in gDNA and cDNA) for three haplotypes (Hap1, Hap2 and Hap5), but significant underexpression for three others (Hap3, Hap4 and Hap6). Hap4 was the most extremely underexpressed and, remarkably, it showed the lowest sequence conservation for the flanking 5.8‐28S coding regions in the gDNA reads but the highest conservation (100%) in the cDNA ones, suggesting the preferential expression of mutation‐free rDNA units carrying this ITS2 haplotype. These results indicate that the ITS2 region of rDNA is far from complete homogenization in this species, and that the different rDNA units are not expressed at random, with some of them being severely downregulated. 相似文献
94.
目的 探讨部队基层官兵的个性特征与人际信任的相关性,为提高部队的凝聚力、战斗力和基层管理效能提供依据. 方法 对520名基层官兵采用人际信任量表和艾森克个性问卷进行测评分析. 结果 基层官兵人际信任量表总分均值为75.11分,总分>75分者占51.9%.义务兵、士官、军官间人际信任量表总分评分均无显著性差异(P>0.05);独生子女官兵人际信任量表总分及信任1、信任3因子分显著低于非独生子女(P<0.05或0.01);城市家庭官兵总分及信任1、信任2因子分均显著低于农村家庭官兵(P<0.05或0.01).基层官兵人际信任量表总分、信任1因子与艾森克个性问卷的精神质、神经质维度呈显著负相关,与内外向、掩饰性维度呈显著正相关(P均<0.01);信任2因子与掩饰性维度呈显著正相关(P<0.05),与神经质维度呈显著负相关(P<0.01);信任3因子与精神质、神经质维度呈显著负相关(P均<0.01),与掩饰性维度呈显著正相关(P<0.01). 结论 基层官兵人际信任水平较高,且个性特征与人际信任水平呈显著相关. 相似文献
95.
I. Drira S. Neji I. Hadrich H. Trabelsi H. Sellami F. Cheikhrouhou R. Guidara F. Makni A. Ayadi 《Mycoses》2014,57(8):453-459
The Trichophyton mentagrophytes complex is the main cause of superficial mycoses in humans and animals. Molecular research has provided useful insights into the taxonomy of this complex to overcome the challenges with conventional diagnostics. The aim of this study was to identify, type and differentiate anthropophilic and zoophilic species of the T. mentagrophytes complex. Sixty clinical samples identified as T. mentagrophytes by morphological characteristics were isolated using polymerase chain reaction‐restriction fragment length polymorphism and sequence analysis of the internal transcribed spacer (ITS) regions. The identification of our strains by conventional methods was confirmed using polymerase chain reaction (PCR) sequencing in 93.34% of the cases. The strains under investigation were recategorised as T. rubrum (Tr2711). In addition, PCR products were independently digested with the restriction endonucleases, MvaI and HinfI, to produce a single dominant profile for T. interdigitale. ITS sequence analysis revealed a polymorphism in the ITS1 and 5.8S regions. Analysis of the consensus sequences distinguished four types of genotypes among our T. interdigitale species. Moreover, ITS type I was the dominant genotype characterising the anthropophilic variant of T. interdigitale. The phylogenetic study showed that only 5% of our strains were zoophilic. PCR sequencing was useful for distinguishing anthropophilic and zoophilic species of T. interdigitale, in which the differentiation is relevant because it helps to prescribe the correct treatment and to identify the surrounding source of infection. 相似文献
96.
目的:探讨太空环境对甘草酸相关基因的诱变作用分析.方法:利用返回式卫星搭载甘草,18 d后返回地球,搭载种子返回地面后与对照组同时种植于实验田中,采集三年生甘草叶子,对甘草酸形成相关基因ITS序列,β-香树酯醇合成酶基因的多态性以及基因表达差异进行了研究.结果:甘草经过卫星搭载后,甘草酸相关基因ITS序列没有发生变化,而甘草酸合成关键基因β-香树酯醇合成酶基因某些位点呈现了差异性,并且太空环境对甘草酸合成关键基因β-香树酯醇合成酶基因表达有一定影响.结论:太空环境对甘草酸相关形成和表达产生一定影响,这些变化对于揭示太空环境对甘草酸形成的基因机制具有重要意义,并且对于后期选育甘草优良种质奠定基础. 相似文献
97.
景天属药用植物DNA条形码研究 总被引:1,自引:0,他引:1
目的:评价DNA条形码候选序列对景天属药用植物及其混伪品的鉴别能力,探索景天属药用植物鉴定的新方法.方法:使用ITS2、rbcL、marK和psbA-trnH序列的通用引物对景天属药用植物进行PCR扩增和测序,通过比较各序列的扩增效率、种内和种间变异的显著性,以及Barcoding gap,采取BLAST 1和Nearest Distance方法评价不同序列的鉴定能力.结果:ITS2序列在采集的景天属几种药用植物中扩增成功率为100%,其种内种问变异差异、Barcoding Gap较psbA-trnH、rbcL序列具有更明显的优势,而且纳入网上48个样品33个种的数据后鉴定成功率仍达到100%.结论:ITS2序列能够准确鉴定景天属药用植物,并将其与常见混伪品区别开,ITS2可推荐为景天属首选的DNA条形码序列. 相似文献
98.
地黄资源遗传多样性分析 总被引:1,自引:0,他引:1
目的:研究不同地区栽培地黄及野生地黄品种间ITS序列差异,为地黄的系统发育和分子鉴定提供依据。方法:用CTAB法提取地黄叶片中总DNA,对PCR产物进行克隆测序,采用MEGA4.0进行系统进化分析。结果:各供试地黄的ITS区序列总长度为613~614 bp,长度变异仅1 bp,其中ITS1长度为224~225 bp,G+C占60.4%~63%;ITS2长度为224~225 bp,G+C占57.1%~65.3%;5.8S长度高度保守,均为164 bp。系统发育分析表明:北京2号地黄与其他地黄资源差异性较大,亲缘关系较远。野生地黄居群内差异较小,居群间没有差异。河南栽培地黄与山西、山东省栽培地黄间没有差异;野生地黄资源中神农山和青天河一带地黄与山东省栽培地黄亲缘关系最近,而河南栽培地黄和山西省栽培地黄与野生地黄没有差异。结论:不同地区地黄资源种间亲缘关系较近,系统分化不明显。 相似文献
99.
Ting Gao Hui Yao Jingyuan Song Chang Liu Yingjie Zhu Xinye Ma Xiaohui Pang Hongxi Xu Shilin Chen 《Journal of ethnopharmacology》2010
Aim of the study
To test whether the ITS2 region is an effective marker for use in authenticating of the family Fabaceae which contains many important medicinal plants.Materials and methods
The ITS2 regions of 114 samples in Fabaceae were amplified. Sequence assembly was assembled by CodonCode Aligner V3.0. In combination with sequences from public database, the sequences were aligned by Clustal W, and genetic distances were computed using MEGA V4.0. The intra- vs. inter-specific variations were assessed by six metrics, wilcoxon two-sample tests and “barcoding gaps”. Species identification was accomplished using TaxonGAP V2.4, BLAST1 and the nearest distance method.Results
ITS2 sequences had considerable variation at the genus and species level. The intra-specific divergence ranged from 0% to 14.4%, with an average of 1.7%, and the inter-specific divergence ranged from 0% to 63.0%, with an average of 8.6%. Twenty-four species found in the Chinese Pharmacopoeia, along with another 66 species including their adulterants, were successfully identified based on ITS2 sequences. In addition, ITS2 worked well, with over 80.0% of species and 100% of genera being correctly differentiated for the 1507 sequences derived from 1126 species belonging to 196 genera.Conclusions
Our findings support the notion that ITS2 can be used as an efficient and powerful marker and a potential barcode to distinguish various species in Fabaceae. 相似文献100.
目的为研究DNA条形码技术在中成药鉴定中的应用,以三七片为研究对象,对方法的适用性、专属性与精密度进行考察。方法收集15批次市售三七片样品,考察三七片DNA提取条件,并对"中药材DNA条形码分子鉴定法指导原则"中PCR扩增、序列获得、结果判定等方法适用性进行确认;收集三七、人参、西洋参,制作三七片及其掺伪品,考察方法的专属性和重现性。结果三七片取样量100 mg,56℃水浴8 h所获得DNA的质量浓度平均值为60.7 ng/μL,PCR扩增、序列获得和结果判定均可获成功;三七、人参和西洋参的ITS2序列长度均为230bp,三七与人参、三七与西洋参的序列间均存在7个稳定的SNP位点,自制三七片和掺伪三七片均可成功获得ITS2序列,不同比例三七与人参、三七与西洋参的测序峰图在SNP位点处呈现相应峰高比的SNP套峰具备专属性;重复性、中间精密度和重现性考察符合《中国药典》2015年版(通则9101)相关要求。结论 ITS2序列作为DNA条形码能够稳定、准确鉴定三七片的原料药材,具备良好的专属性和精密度,三七片DNA条形码分子鉴定法将为保障三七片临床用药安全提供新的技术手段,并对《中国药典》其他收载单方制剂的鉴定提供参考。 相似文献