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隐性“区隔”与显性支配——论审美趣味与审美权力的双向建构 被引量:9
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作者 黄仲山 《山东大学学报(哲学社会科学版)》 CSSCI 北大核心 2014年第6期147-152,共6页
在审美文化领域,审美趣味作为一种隐性的"区隔"力量,形成文化资本占有者对其他阶层审美活动的软性控制和引导,这与通过对审美资源的硬性占有而呈现出显性支配力的审美权力形成对应关系。在审美权力到审美趣味领域的延伸过程中... 在审美文化领域,审美趣味作为一种隐性的"区隔"力量,形成文化资本占有者对其他阶层审美活动的软性控制和引导,这与通过对审美资源的硬性占有而呈现出显性支配力的审美权力形成对应关系。在审美权力到审美趣味领域的延伸过程中,呈现了一种由硬到软、由显性到隐性的向度;另一方面,审美趣味的层级结构又反哺并巩固已有的审美权力结构,两者形成一种相互指向对方的双向建构关系。在这种关系形态下,需要结合时代语境反思当下社会文化中的权力颠覆与趣味博弈,从中趋利避害,实现社会审美文化的和谐健康发展。 展开更多
关键词 隐性“区隔” 显性支配 审美趣味 审美权力 双向建构
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体育节目受众的社会“区隔”——基于“场域-惯习”理论下的实证研究
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作者 李致富 刘伟 《安徽职业技术学院学报》 2022年第2期41-45,共5页
文章从布迪厄的“场域-惯习”理论出发,基于中国网民社会意识调查数据分析了体育节目受众的“区隔”差异性特征。通过定序Ologit回归分析,得出以下结论:喜欢体育类节目的受众人口学特征差异较大,表明体育类节目的受众存在社会区隔;教育... 文章从布迪厄的“场域-惯习”理论出发,基于中国网民社会意识调查数据分析了体育节目受众的“区隔”差异性特征。通过定序Ologit回归分析,得出以下结论:喜欢体育类节目的受众人口学特征差异较大,表明体育类节目的受众存在社会区隔;教育资本和社会资本对体育节目的受众影响并非呈现完全正相关,说明了体育类节目的“场域”存在界限。研究揭示,现阶段提高体育节目收视率首要因素是居民收入的增加和厚植社会体育文化。 展开更多
关键词 体育节目 “场域-惯习” 经济资本 社会“区隔”
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“文艺场域”“区隔”理论下的“80后”作家图书出版
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作者 杨曙 《出版科学》 CSSCI 2011年第4期49-52,共4页
出版业在"80后"作家图书的商品化趋势比在传统精英作家出版中要明晰得多。传统精英作家图书出版往往以"高等教育""高等文化"等为标准定位,使学者习惯倾向围绕既存的"高等"观念的普遍性,而忽略... 出版业在"80后"作家图书的商品化趋势比在传统精英作家出版中要明晰得多。传统精英作家图书出版往往以"高等教育""高等文化"等为标准定位,使学者习惯倾向围绕既存的"高等"观念的普遍性,而忽略了"80后"作家图书出版与众不同的个别性。"80后"作家图书的出版则可抛射出改变本身以精英面貌出现的精英作家图书作为"文艺场域"一部分的内在能动。"80后"作家图书的出版又具有很强的区分性和等级性。 展开更多
关键词 “80后”作家图书出版 “文艺场域” “区隔”
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从“区隔”理论看新媒体科普下用户的圈层化表现与利用 被引量:1
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作者 马月飞 焦光宇 《西部广播电视》 2022年第2期1-3,共3页
科学传播是一种社会现象,技术和社会的互动促使科普的出现。本文基于法国社会学家布尔迪厄的“区隔”理论,总结我国新媒体科普下用户的圈层化表现,阐释新媒体在用户分层中发挥的作用,同时对新媒体科普的发展提出建设性意见,包括“垂直+... 科学传播是一种社会现象,技术和社会的互动促使科普的出现。本文基于法国社会学家布尔迪厄的“区隔”理论,总结我国新媒体科普下用户的圈层化表现,阐释新媒体在用户分层中发挥的作用,同时对新媒体科普的发展提出建设性意见,包括“垂直+矩阵”的新媒体科普运营、众包科普、长尾科普,以期为相关人员提供参考。 展开更多
关键词 新媒体 科普 “区隔” 圈层化
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ITS1 SEQUENCES OF NUCLEAR RIBOSOMAL DNA IN WILD RICES AND CULTIVATED RICES OF CHINA AND THEIR PHYLOGENETIC IMPLICATIONS 被引量:22
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作者 周毅 邹喻苹 +2 位作者 洪德元 周骏马 陈受宜 《Acta Botanica Sinica》 CSCD 1996年第10期785-791,共7页
The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced wi... The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced with automated fluorescent sequencing. The sequences of ITS1 ranged from 193 bp to 218 bp in size and G/C content varied from 69.3% to 72.7%. In pairwise comparisons among the five taxa, sequence site divergence ranged from 1.5% to 10.6%. Phylogenetic analysis of ITS1 sequences using Wagner parsimony generated a single well resolved tree, which revealed that Oryza rufipogon was much more closely related to cultivated rice species than to the other two wild species. Oryza granulata was less closely related to either cultivated rice species or the other two wild species, and might be a unique and isolated taxon in the genus Oryza. The phylogenetic relationships of the three wild rice species and two cultivated rice subspecies inferred from ITS1 sequences is highly concordant with those based on the molecular evidence from isozyme, chloroplast DNA (cpDNA), mitochondrial DNA(mtDNA) and nuclear DNA (nDNA) of the genus Oryza . 展开更多
关键词 Wild rice Cultivated rice ITS1 of rDNA Sequence analysis PHYLOGENY
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Infrageneric and Sectional Relationships in the Genus Rhododendron (Ericaceae) Inferred from ITS Sequence Data 被引量:11
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作者 高连明 李德铢 +1 位作者 张长芹 杨俊波 《Acta Botanica Sinica》 CSCD 2002年第11期1351-1356,共6页
The internal transcribed spacer (ITS) regions of nuclear ribosomal DNA (including 5.8S rRNA) of 15 Rhododendron, species, representing most sections of the genus, one Ledum species and Cassiope fastigiata were sequenc... The internal transcribed spacer (ITS) regions of nuclear ribosomal DNA (including 5.8S rRNA) of 15 Rhododendron, species, representing most sections of the genus, one Ledum species and Cassiope fastigiata were sequenced. Together with the ITS sequences of 13 selected Rhododendron species and Bejaria racemosa downloaded from GenBank, we explored the infrageneric and sectional relationships of this important North Temperate genus by employing maximum-parsimony analysis using PAUP software. C. fastigiata and B. racemosa were designated as outgroups. The ITS-based tree inferred that: (1) Rhododendron was a well-supported monophyletic group, while subg. Therorhodion was basal to the rest of the genus; (2) Ledum was a member of Rhododendron, and its close relationship with the lepidote rhododendron was confirmed; (3) the lepidote rhododendron plus Ledum formed a strongly-supported monophyletic clade which was sister to the rest of the elepidote rhododendron; (4) the elepidote rhododendron formed a weakly-supported clade within which the monophyly of subg. Hynwrianthes and subg. Tsutsusi were strongly supported, while subg. Pentanthera and subg. Azaleastrum were polyphyletic; and (5) the monophyly of sect. Choniastnini, (subg. Azaleastrum) was strongly-supported, while subg. Tsutsusi could be sister to a weakly-supported clade composed of two sampled species of sect. Azaleastrum (subg. Azaleastrum) together with R. sentibarbatum, of subg. Mumeazalea. 展开更多
关键词 RHODODENDRON internal transcribed spacer (ITS) PHYLOGENY infrageneric relationships
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Phylogenetic Relationship of an Extremely Endangered Species, Pinus squamata (Pinaceae) Inferred from Four Sequences of the Chloroplast Genome and ITS of the Nuclear Ribosomal DNA 被引量:1
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作者 张志勇 杨俊波 李德铢 《Acta Botanica Sinica》 CSCD 2003年第5期530-535,共6页
Pinus squamata X. W. Li, a recently-described species of the Pinaceae, is an extremely endangered pine with only 32 individuals in the wild. This species was thought to be intermediate between P. bungeana Zuec. ex End... Pinus squamata X. W. Li, a recently-described species of the Pinaceae, is an extremely endangered pine with only 32 individuals in the wild. This species was thought to be intermediate between P. bungeana Zuec. ex Endl. of subgen. Strobus and P. yunnanensis Franch. of subgen. Pinus by the original author. We made an effort to address the question of the phylogenetic relationship of this peculiar and important species in the context of the major groups of the genus Pinus by using sequences of the rbcL, matK,genes, rpl20-rps18 spacer, trnV intron of the chloroplast genome and the nuclear ribosomal ITS region. The results of the separated analysis and the combined analysis of the four cpDNA sequences and ITS sequence indicated that P. squamata was a stable member of subsect. Gerardianae and P. gerardiana Wall. was the closest species of P. squamata phylogenetically. As a result, the causes of the distribution pattern of subsect. Gerardianae were also discussed. 展开更多
关键词 Pinus squamata phylogenetic relationship rbc L mat K rpl20-rps 18 trn V ITS
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Design Concept for Key Parameters of Reverse Conducting GCT 被引量:2
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作者 王彩琳 高勇 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第10期1243-1248,共6页
Presented is design concept for key parameters o f the reverse conducting gate commutated thyristor (RC-GCT),such as the thickness and concentration of n-base region and the transparent anode region,and the wi dth o... Presented is design concept for key parameters o f the reverse conducting gate commutated thyristor (RC-GCT),such as the thickness and concentration of n-base region and the transparent anode region,and the wi dth of separation region between asymmetric GCT and PIN diode.A structure model of the RC-GCT is set up based on the design concept and its characteristics are analyzed.The simulation results show the design concept is reasonable. 展开更多
关键词 power semiconductor device reverse con ducting gate commutated thyristor transparent anode separation region
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Microstructure and defect of titanium alloy electron beam deep penetration welded joint 被引量:8
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作者 张秉刚 石铭霄 +1 位作者 陈国庆 冯吉才 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2633-2637,共5页
The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat ... The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat affected zone was divided into fine-grained zone and coarse-grained zone, the microstructure of fine-grained zone was primary α phase + β phase + equiaxed α phase, and the microstructure of coarse-grained zone was primary α phase + acicular α′ phase; the microstructure of base metal zone basically consisted of primary α phase, and a small amount of residual β phase sprinkled. The forming. reason of cold shut was analyzed, and the precaution of cold shut was proposed. 展开更多
关键词 TA15 titanium alloy electron beam welding MICROSTRUCTURE phase composition cold shut defect weld zone heataffected zone
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Screening of the Gene for Chlorella Identification and Identification of oil-producing Microalgae 被引量:2
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作者 何茹 刘君寒 +1 位作者 王士安 李福利 《Agricultural Science & Technology》 CAS 2011年第6期795-798,共4页
[Objective] The aim was to select suitable gene for Chlorella identification and to identify the oil-producing microalgae.[Method] Four candidate gene sequences,the nuclear genomic rDNA of the 18S rRNA gene,internal t... [Objective] The aim was to select suitable gene for Chlorella identification and to identify the oil-producing microalgae.[Method] Four candidate gene sequences,the nuclear genomic rDNA of the 18S rRNA gene,internal transcribed spacer(ITS),internal transcribed spacer Ⅱ(ITS Ⅱ)and the chloroplast rbcL gene,were selected for Chlorella molecular identification.Through these four candidate genes,the genetic variability and distinguish ability between intra-species and inter-species was analyzed to choose the right genes for identification of the high oil-content Chlorella.On this basis,application of these gene segments were classified and identified for five fresh-water isolated Chlorella,which oil-content is more than 30%.[Result] ITS gene was a suitable gene because of its high variation and short fragment length,meanwhile its genetic distance intra-species(0.439 6±0.135 9)was larger than inter-species(0.045 7±0.084 3).Its sequence length varied between different species whereas highly conserved in the same species.By the application of ITS sequences,respectively,five high oil-content stains were identified as one C.vulgaris,two strains of C.sorokiniana and two strains of algae Chlorella sp.[Conclusion] This study had provided reference for the establishment of identification gene pool of Chlorella. 展开更多
关键词 Oil-producing microalgae Molecular identification Internal transcribed spacers 18S rRNA gene Genetic distance
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Chemical and molecular characterization of Hong Dangshen,a unique medicinal material for diarrhea in Hong Kong
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作者 张艳波 江仁望 +6 位作者 李松林 乔春峰 韩全斌 徐宏喜 黄家乐 毕培曦 邵鹏柱 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第3期202-207,共6页
Aim To investigate the plant origin and the identity of the red substance on the surface of Hong Dangshen, a unique medicinal material for diarrhea in Hong Kong. Methods The HPLC fingerprints and 5S rRNA gene spacer s... Aim To investigate the plant origin and the identity of the red substance on the surface of Hong Dangshen, a unique medicinal material for diarrhea in Hong Kong. Methods The HPLC fingerprints and 5S rRNA gene spacer sequences of Hong Dangshen were obtained and compared with those of genuine species of Radix Codonopsis. The X-ray diffraction spectrum of the red substance was analyzed and compared with that of Halloysitum fingerprints to the Codonopsis species and the highest similarity to Rubrum. Results Hong Dangshen showed very similar HPLC Codonopsis pilosula var. modesta in terms of 5S rRNA gene spacer sequences. The X-ray diffraction spectrum of the red substance was consistent with that of Halloysitum Rubrum. Conclusion The source plant of Hong Dangshen was suggested to be Codonopsis pilosula var. modesta, one of the genuine original plants of Radix Codonopsis (Dangshen) in the China Pharmacopoeia (2005 edition). The red substance on the surface of Hong Dangshen was indicated to be Halloysitum Rubrum, a traditional medicinal mineral for chronic diarrhea. Our data suggest that Hong Dangshen is derived from the roots of Codonopsis pilosula var. modesta which has been processed with Halloysitum Rubrum, and the name is suggested to be Radix Codonopsis Praeparata Halloysita Rubra. 展开更多
关键词 Radix Codonopsis Praeparata Halloysita Rubra Codonopsis pilosula var. modesta HPLC 5S rRNA gene spacer X- ray Halloysitum Rubrum LOBETYOLIN
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Phylogenetic analyses of four species of Ulva and Monostroma grevillei using ITS, rbcL and 18S rDNA sequence data 被引量:4
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作者 林中姮 沈颂东 +1 位作者 陈伟洲 李慧慧 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期97-105,共9页
Chlorophyta species are common in the southern and northern coastal areas of China. In recent years, frequent green tide incidents in Chinese coastal waters have raised concerns and attracted the attention of scientis... Chlorophyta species are common in the southern and northern coastal areas of China. In recent years, frequent green tide incidents in Chinese coastal waters have raised concerns and attracted the attention of scientists. In this paper, we sequenced the 18S rDNA genes, the internal transcribed spacer (ITS) regions and the rbcL genes in seven organisms and obtained 536-566 bp long ITS sequences, 1 377-I 407 bp long rbcL sequences and 1 718-1 761 bp long partial 18S rDNA sequences. The GC base pair content was highest in the ITS regions and lowest in the rbcL genes. The sequencing results showed that the three Ulvaprolifera (or U. pertusa) gene sequences from Qingdao and Nan'ao Island were identical. The ITS, 18S rDNA and rbcL genes in U. prolifera and U. pertusa from different sea areas in China were unchanged by geographic distance. U.flexuosa had the least evolutionary distance from U. californica in both the ITS regions (0.009) and the 18S rDNA (0.002). These data verified that Ulva and Enteromorpha are not separate genera. 展开更多
关键词 ULVA ITS region RBCL 18S rDNA PHYLOGENY sequences analysis
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An improved PCR method for direct identification of Porphyra(Bangiales,Rhodophyta) using conchocelis based on a RUBISCO intergenic spacer 被引量:2
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作者 王超 董栋 +4 位作者 王广策 张宝玉 彭光 许璞 汤晓荣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期513-518,共6页
An improved method of PCR in which the small segment of conchocelis is amplified directly without DNA extraction was used to amplify a RUBISCO intergenic spacer DNA fragment from nine species of red algal genus Porphy... An improved method of PCR in which the small segment of conchocelis is amplified directly without DNA extraction was used to amplify a RUBISCO intergenic spacer DNA fragment from nine species of red algal genus Porphyra(Bangiales,Rhodophyta),including Porphyra yezoensis(Jiangsu,China),P.haitanensis(Fujian,China),P.oligospermatangia(Qingdao,China),P.katadai(Qingdao,China),P.tenera(Qingdao,China),P.suborboculata(Fujian,China),P.pseudolinearis(Kogendo,Korea),P.linearis(Devon,England),and P.fallax(Seattle,USA).Standard PCR and the method developed here were both conducted using primers specific for the RUBISCO spacer region,after which the two PCR products were sequenced.The sequencing data of the amplicons obtained using both methods were identical,suggesting that the improved PCR method was functional.These findings indicate that the method developed here may be useful for the rapid identification of species of Porphyra in a germplasm bank.In addition,a phylogenetic tree was constructed using the RUBISCO spacer and partial rbcS sequence,and the results were in concordant with possible alternative phylogenies based on traditional morphological taxonomic characteristics,indicating that the RUBISCO spacer is a useful region for phylogenetic studies. 展开更多
关键词 RHODOPHYTA PORPHYRA RUBISCO intergenic spacer DNA sequence PCR
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Phylogenetic relationships within the genus Aspidisca(Protozoa,Ciliophora,Euplotida) revealed by ITS1-5.8S-ITS2 region sequences 被引量:2
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作者 黄洁 伊珍珍 +3 位作者 苗苗 AL-RASHEID KhaledA.S 宋微波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期277-283,共7页
Abstract The internal transcribed spacer regions (ITS1 and ITS2) and 5.8S rRNA genes were sequenced in six populations of four Aspidisca species, namely A. leptaspis, A. orthopogon, A. rnagna and A. aculeata. Phylog... Abstract The internal transcribed spacer regions (ITS1 and ITS2) and 5.8S rRNA genes were sequenced in six populations of four Aspidisca species, namely A. leptaspis, A. orthopogon, A. rnagna and A. aculeata. Phylogenetic trees were constructed by means of Bayesian inference (BI), Maximum Parsimony (MP), Neighbor-Joining (NJ), and Maximum Likelihood (ML) to assess the inter- and intra-species relationships within the genus Aspidisca. All trees show similar topologies with stable supports and indicate that: (1) four well known groups, i.e., Oligotrichia, Stichotrichia, Choreotrichia and Hypotrichia, are distinctly outlined within the class Spirotrichea, and all are monophyletic other than Hypotrichia; (2) members of Aspidisca can be distinguished well, based on the ITSI-5.SS-ITS2 region sequences, and A. leptaspis and A. magna shared a closer relationship than other species; (3) Aspidisca and Euplotes branch early in the subclass Hypotrichia. To compare the phylogenetic relationships based on different genes, SSU rRNA trees were also constructed with nearly the same species inclusion, which revealed different topologies of inter-species, inter-genera and inter-subclasses. 展开更多
关键词 marine ciliates Aspidisca PHYLOGENY internal transcribed spacer 5.8S rRNA
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First record of Biecheleria cincta (Dinophyceae) from Chinese coasts, with morphological and molecular characterization of the strains 被引量:4
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作者 罗肇河 杨维东 +1 位作者 徐斌 顾海峰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期835-845,共11页
The presence ofBiecheleria cincta (=Woloszynskia cincta) in the Chinese coasts is reported for the first time. In scanning electron microscope, three to five series of vesicles and an elongated apical vesicle (EAV... The presence ofBiecheleria cincta (=Woloszynskia cincta) in the Chinese coasts is reported for the first time. In scanning electron microscope, three to five series of vesicles and an elongated apical vesicle (EAV) were visible in the epicone, and both the hypocone and the cingulum had three series of vesicles each. Thin sections revealed that B. cincta possesses stalked pyrenoids and an unusual eyespot consisting of a stack of cistemae with brick-like materials (type E), thus supporting its transfer from Woloszynskia to Biecheleria. Spiny cysts formed spontaneously in culture, with an encystment rate of around 20%. Both large subunit ribosomal DNA (LSU rDNA) and internal transcribed spacer region (ITS) sequences in 12 strains from the Chinese coasts were determined. Phylogenetic analyses based on LSU rDNA and ITS sequences using Bayesian inference and maximum likelihood revealed two distinct ribotypes (referred to as ribotype A and B) in B. cincta. ITS region pairwise distances within B. eincta ranged from 0.024 to 0.072, suggesting the existence of a complex of cryptic species. 展开更多
关键词 Biecheleria CYST internal transcribed spacer region (ITS) type E eyespot ULTRASTRUCTURE Woloszynskia cincta
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Molecular diversity of Enteromorpha from the coast of Yantai:a dual-marker assessment 被引量:1
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作者 刘海燕 刘正一 +2 位作者 王寅初 赵玉山 秦松 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第6期1210-1215,共6页
We collected nine Enteromorpha specimens from the coast of Yantai and evaluated their diversity based on analyses of their ITS(internal transcribed spacer) and 5S rDNA NTS(non-transcribed spacer) sequences.The ITS seq... We collected nine Enteromorpha specimens from the coast of Yantai and evaluated their diversity based on analyses of their ITS(internal transcribed spacer) and 5S rDNA NTS(non-transcribed spacer) sequences.The ITS sequences showed slight nucleotide divergences between Enteromorpha linza and Enteromorpha prolifera.In contrast,multiple highly variable regions were found in the ITS region of Enteromorpha flexuosa.In general,there were more variable sites in the NTS region than in the ITS region in the three species.The variations in 5S rDNA NTS sequences indicated that the molecular diversity of Enteromorpha from the coast of Yantai is very high.However,a phylogenetic tree constructed using 5S rDNA NTS sequence data indicated that genetic differences were not directly related to geographical distribution. 展开更多
关键词 ENTEROMORPHA internal transcribed spacer (ITS) 5SrDNA non-transcribed spacer (NTS) molecular diversity
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Molecular identification based on ITS sequences for Kappaphycus and Eucheuma cultivated in China 被引量:2
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作者 赵素芬 何培民 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第6期1287-1296,共10页
The systematic classification of the Eucheumatoideae is difficult because of their variable morphology and interpretation of reproductive structures. Kappaphycus and Eucheuma specimens cultivated on the Hainan and Fuj... The systematic classification of the Eucheumatoideae is difficult because of their variable morphology and interpretation of reproductive structures. Kappaphycus and Eucheuma specimens cultivated on the Hainan and Fujian coast of China were introduced from Vietnam, the Philippines and Indonesia. Combined with morphological characteristics, all Kappaphycus and Eucheuma cultivated strains were identified by internal transcribed spacer (ITS) sequences. The phylogenetic tree was constructed using neighbor-joining and maximum likelihood methods. The results indicate that different ITS sequence lengths occurred in the different genera and species. An obvious difference in morphology could be found in the protuberance shape between Kappaphycus and Eucheuma. The protuberance in Eucheuma was thorn-like and in Kappaphycus was wartlike or papillate. Their ITS sequence lengths differed significantly in nucleotide variation rates up to 58.55%-63.90%. All nucleotide variations occurred in the ITS1 and ITS2 regions except for five nucleotide transversions in the 5.8S rDNA region. In addition, the difference was at the branches among congeneric species. Kappaphycus sp. had branches with small buds, while K. alvarezii did not have such a feature. The nucleotide variation rates varied from 7.02% to 7.48% among species; within the same species of the clades it was <1.20%. Eucheumatoideae algae cultivated in China consisted of three clades, K. alvarezii, Kappaphycus sp., and E. denticulatum. The results indicate that ITS sequence analysis was an effective way for identification of interspecies and intraspecies phylogenetic relationships and might provide a clue for molecular identification of algal Eucheumatoideae. 展开更多
关键词 EUCHEUMA identification KAPPAPHYCUS ITS RHODOPHYTA
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Phylogeography of Batrachospermum arcuatum in North China based on ITS sequence data 被引量:1
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作者 吉莉 谢树莲 +1 位作者 陈乐 冯佳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第2期372-376,共5页
Batrachospermum arcuatum Kylin is typically dioecious,although some monoecious specimens have been collected from four locations in North China.In this study,B.arcuatum populations,including monoecious and dioecious t... Batrachospermum arcuatum Kylin is typically dioecious,although some monoecious specimens have been collected from four locations in North China.In this study,B.arcuatum populations,including monoecious and dioecious thalli,were collected from seven stream segments.The nuclear DNA internal transcribed spacer(ITS)region was sequenced for the seven populations,and a phylogenetic tree was constructed using Bayesian inference to assess intraspecifi c relationships.A haplotype network was also created.The ITS region in B.arcuatum from North China comprised 822–853 bp,with 10 haplotypes detected from the seven locations.The results of this study support the inclusion of monoecious individuals in the species B.arcuatum. 展开更多
关键词 Batrachospermum arcuatum nrDNA internal transcribed spacer (ITS) IDENTIFICATION PHYLOGENY
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Characterization of Genome-Wide Microsatellites of Saccharina japonica Based on a Preliminary Assembly of Illumina Sequencing Reads 被引量:2
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作者 ZHANG Linan PENG Jie +3 位作者 LI Xiaojie CUI Cuiju SUN Juan YANG Guanpin 《Journal of Ocean University of China》 SCIE CAS 2016年第3期523-532,共10页
Microsatellites or simple sequence repeats(SSR) function widely and locate dependently in genome. However, their characteristics are often ignored due to the lack of genomic sequences of most species. Kelp(Saccharina ... Microsatellites or simple sequence repeats(SSR) function widely and locate dependently in genome. However, their characteristics are often ignored due to the lack of genomic sequences of most species. Kelp(Saccharina japonica), a brown macroalga, is extensively cultured in China. In this study, the genome of S. japonica was surveyed using an Illumina sequencing platform, and its microsatellites were characterized. The preliminarily assembled genome was 469.4 Mb in size, with a scaffold N_(50) of 20529 bp. Among the 128370 identified microsatellites, 90671, 25726 and 11973 were found in intergenic regions, introns and exons, averaging 339.3, 178.8 and 205.4 microsatellites per Mb, respectively. These microsatellites distributed unevenly in S. japonica genome. Mononucleotide motifs were the most abundant in the genome, while trinucleotide ones were the most prevalent in exons. The microsatellite abundance decreased significantly with the increase of motif repeat numbers, and the microsatellites with a small number of repeats accounted for a higher proportion of the exons than those of the intergenic regions and introns. C/G-rich motifs were more common in exons than in intergenic regions and introns. These characteristics of microsatellites in S. japonica genome may associate with their functions, and ultimately their adaptation and evolution. Among the 120140 pairs of designed microsatellite primers, approximately 75% were predicted to be able to amplify S. japonica DNA. These microsatellite markers will be extremely useful for the genetic breeding and population evolution studies of kelp. 展开更多
关键词 Saccharinajaponica GENOME MICROSATELLITE CHARACTERIZATION
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Sequence analysis of rDNA intergenic spacer region (IGS) as a tool for phylogenetic studies in Trichoderma spp.
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作者 Mercatelli Elisabetta Pecchia Susanna +1 位作者 Ciliegi Sandro Vannacci Giovanni 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期460-461,共2页
Different from ribosomal genes, which contain highly conserved sequences that are detected in all organisms, the intergenic spacer of rDNA (IGS) appears to be the most rapidly-evolving spacer region. For this reason w... Different from ribosomal genes, which contain highly conserved sequences that are detected in all organisms, the intergenic spacer of rDNA (IGS) appears to be the most rapidly-evolving spacer region. For this reason we tested this region for phylogenetic studies. This report focuses on the study of IGS sequences of isolates belonging to Trichoderma section (T. viride, T. koningii, T. hamatum, T. erinaceus, T. asperellum) and Pachybasium section (T. harzianum, T. crassum, T. fasciculatum, T. oblongisporum, T. virens). Using the primer pair 28STD and CNS1, the Fast Start Taq DNA Polymerase (Roche), and a three temperature PCR protocol, products ranging from ca 1900 to 2400 bp were obtained from all tested isolates. The PCR product of 16 Trichoderma spp. isolates was cloned into a pGEM-TEeasy Vector (Promega) and sequenced. Based on a BLAST search we can conclude that the PCR product represents the whole IGS region. Multiple alignments of IGS sequences revealed two portions with different homology level. Portion A (ca 1660 bp) is the portion that contains 3’ end of 28S gene and is the more variable, while portion B (ca 830 bp), that contains the 3’ end of IGS region and the 5’ end of 18S gene, is the less variable. Comparing all sequences in region A 705 identical pairs occur out of 1704 total nucleotides (41.4%), while in region B identical pairs were 723 out of 832 total nucleotides (86.9%) . Sequence comparison of the two regions at intraspecific level (where it was possible) showed higher variability in region A (0.17%-6.8%) than in region B (0.0%-1.0%) . At interspecific level, performing all possible comparisons, the variability of region A (19.5%-52.7%) and B (0.8%- 16.9%). were significantly higher. Comparing sequences of species belonging to Trichoderma section variability of the two regions appears reduced if compared with that obtained from comparisons of species belonging to Pachybasium section. On the basis of sequence alignment, phylogenetic trees were obtained either with entire IGS, with region A, and with region B. Results of this analysis revealed that all isolates belonging to Trichoderma section grouped separately from isolates belonging to Pachybasium section. IGS region allowed us to group species according to their taxonomic position. The topology of the tree did not change substantially, varying in genetic distance only. Performing a GenBank search sequences representing the final portion of the IGS region of other fungal species were found, and we carried out a multiple alignment using also our sequences of Trichoderma spp. and Diaporthe helianthi. The phylogeny inferred from sequence alignment matched the generally accepted morphology-based classification and was identical to other molecular schemes at high taxonomic level. Data analysis was useful in establishing a broad-scale phylogeny of Ascomycota and was also useful in sorting them into statistically-supported clades. The tree showed that Trichoderma occurred in a well-supported terminal subclade of a larger clade that also contained other genera belonging to Hypocreales order. Sequence analysis of the Trichoderma spp. IGS region allowed us to design a specific PCR primer that was successfully used to amplify region A. The new reverse primer LCR2, that recognize all Trichoderma isolates, was identified in region B and confirmed for its specificity on the DNA of fungi belonging to other Ascomycota genera. Results obtained showed that IGS region seems to be an interesting and versatile tool for phylogenetic analysis, for resolving some taxonomic problems and for constructing specific primer useful for different purposes. 展开更多
关键词 IGS RDNA sequences Trichoderma spp. PHYLOGENY
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