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从复合词的“异序”论汉语的类型学特征 被引量:11
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作者 林华东 《泉州师范学院学报》 2004年第3期68-73,共6页
汉语复合词出现异序现象是汉语词汇从单音词向双音词发展的必然产物,是汉语的韵律要求和共同的语素义为之造就了支撑条件,是丰富的方言提供了生存的土壤。汉语构词上语序AB式和BA式并存的事实证明,汉语不仅有"修饰语+中心语"... 汉语复合词出现异序现象是汉语词汇从单音词向双音词发展的必然产物,是汉语的韵律要求和共同的语素义为之造就了支撑条件,是丰富的方言提供了生存的土壤。汉语构词上语序AB式和BA式并存的事实证明,汉语不仅有"修饰语+中心语"的偏正式合成词,也同时具有"中心语+修饰语"的正偏式合成词,后者并非受亲属语言或古越语的影响。 展开更多
关键词 复合词 “异序” 汉语 类型学 双音词 语素义 偏正式 正偏式
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海南闽语的“异序词” 被引量:1
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作者 符其武 梁鲜 《新东方》 2008年第10期51-53,共3页
顾名思义,“异序词”是指有关词索在排列的次序上不顺乎寻常的词语。 异序是相对于顺序而言的,因此“异序词”的概念,本身就蕴含着一个条件的预设:存在一个假定的“顺序词”参照体。因此,在无特别指定的情况下,本文所称“异序词... 顾名思义,“异序词”是指有关词索在排列的次序上不顺乎寻常的词语。 异序是相对于顺序而言的,因此“异序词”的概念,本身就蕴含着一个条件的预设:存在一个假定的“顺序词”参照体。因此,在无特别指定的情况下,本文所称“异序词”是指相对于普通话中对应词的语素序而言的。例如,普通话说“公鸡”,那么方言中的“鸡公”就是异序词。反过来,尽管普通话的“饼干”具有非偏正关系的“逆构”特点,但由于方言也说“饼干”,在词语的语素序上与普通话相同,则不属于本文“异序词”的范畴。 展开更多
关键词 海南闽语 普通话 偏正关系 参照体 对应词 词语 语素 “异词”
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Cytological and Molecular Identification of Alien Chromatin in Giant Spike Wheat Germplasm 被引量:7
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作者 窦全文 陈佩度 解俊峰 《Acta Botanica Sinica》 CSCD 2003年第9期1109-1115,共7页
Alien chromosomes of twelve giant spike wheat germplasm lines were identified by C-banding, genomic in situ hybridization (GISH), sequence characterized amplified region (SCAR), and random amplified polymorphic DNA (R... Alien chromosomes of twelve giant spike wheat germplasm lines were identified by C-banding, genomic in situ hybridization (GISH), sequence characterized amplified region (SCAR), and random amplified polymorphic DNA (RAPD). All lines showed a chromosome number of 2n = 42, five of them carried both a pair of wheat-rye (Triticum aestivum-Secale cereal) 1BL/1RS translocation chromosomes and a pair of Agropyron intermedium (Ai) chromosomes, three carried a pair of Ai chromosomes only, three others carried a pair of 1BL/1RS chromosomes only, and one carried neither 1BL/1BS nor Ai chromosome. Further identification revealed that the identical Ai chromosome in these germplasm lines substituted the chromosome 2D of common wheat (T aestivum L.), designated as 2Ai. The genetic implication and further utilization of 2Ai in wheat improvement were also discussed. 展开更多
关键词 giant spike germplasm 1 BL/1 RS Agropyron intermedium C-banding genomic in situ hybridization (GISH) sequence characterized amplified region (SCAR) random amplified polymorphic DNA (RAPD)
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Sequence Difference of Mitochondrial DNA Control Region and Genetic Differentiation of Cervinae in China 被引量:1
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作者 涂剑锋 邢秀梅 +2 位作者 徐佳萍 杨颖 杨福合 《Agricultural Science & Technology》 CAS 2011年第11期1717-1720,共4页
[Objective] The study aimed at analyzing Genetic Differentiation of Cervinae. [Method] The complete mitochondrial DNA control region of five species of Cervinae was determined by direct DNA sequencing. Homologous sequ... [Objective] The study aimed at analyzing Genetic Differentiation of Cervinae. [Method] The complete mitochondrial DNA control region of five species of Cervinae was determined by direct DNA sequencing. Homologous sequences of others Cervinae were gained from GenBank, and then analyzed through biology software. [Result] The lengths of their control region were 921-1 072 bp, the nucleotide content of T, A, C, and G was 32.1%, 30.2%, 22.7% and 15.0% separately. Genetic distance of each species ranged from 0.062-0.106, which belonged to level of inter-genus. The molecular phylogenetic tree indicated that red deer, skia deer and White-lipped Deer had close relationship, and they constituted one branch with sambar deer. Eld's deer and elk deer constituted the second branch, and hog deer constituted the third branch alone. [Conclusion] Hog deer and fallow deer should be incorporated in Cervus, divergence time is about 1.55-2.60 million years among Cervinae in China. 展开更多
关键词 Cervinae Control Region Sequence Analysis PHYLOGENY
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Micro-heterogeneity of Storage Glutelin in Rice Seed 被引量:4
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作者 曲乐庆 魏晓丽 +3 位作者 佐藤光 小川雅广 熊丸敏博 贾旭 《Acta Botanica Sinica》 CSCD 2001年第8期815-820,共6页
The storage glutelin in rice ( Oryza sativa L.) seeds could be separated at least into more than 13 acidic and 19 basic polypeptides by two dimensional electrophoresis. Rice glutelin might be mainly controlled by abou... The storage glutelin in rice ( Oryza sativa L.) seeds could be separated at least into more than 13 acidic and 19 basic polypeptides by two dimensional electrophoresis. Rice glutelin might be mainly controlled by about six major genes according to the expression of glutelin polypeptides. The acidic polypeptide of glutelin could be clearly separated into two groups by peptide mapping and N-terminal amino acid sequence analysis. These two groups were just in accord with the GluA and GluB subfamilies exactly. 展开更多
关键词 rice glutelin two-dimensional electrophoresis N-terminal amino acid sequence
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The New Discoveries of Specific Characteristics of Yulania Spach 被引量:2
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作者 赵东欣 赵东武 孙军 《Agricultural Science & Technology》 CAS 2008年第1期54-59,共6页
The research history and new discoveries of the specific characteristics of Yulania Spach were reported, as to the specific characteristics, such as the terminal , axillary and fascicled similar flower buds,sometimes ... The research history and new discoveries of the specific characteristics of Yulania Spach were reported, as to the specific characteristics, such as the terminal , axillary and fascicled similar flower buds,sometimes polycymes; 2-4 flower types of a plant; two spathe-like stipoles of single flower; drape or overlap of tepals, deep split or shallow split on the edge of tepals. The discoveries could provide valuable information for the further studies on the taxonomic system, anthotaxical evolution, phylogenetic relationship and breeding. 展开更多
关键词 Yulania Spach Specific characteristics New discoveries
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南堡凹陷高北地区“异迁移”型层序构型成因及其对沉积的意义 被引量:3
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作者 刘可行 甘华军 +5 位作者 陈思 孟令箭 李潇鹏 柯友亮 马江浩 王思洋 《地球科学》 EI CAS CSCD 北大核心 2020年第10期3603-3617,共15页
受到区域性幕式构造活动的影响,南堡凹陷高北地区沙河街组时期发育典型的"异迁移"型层序地层构型.充分利用钻井、测井和高分辨率三维地震等资料,运用层序地层学和沉积盆地分析相关理论和方法,系统地研究了"异迁移"... 受到区域性幕式构造活动的影响,南堡凹陷高北地区沙河街组时期发育典型的"异迁移"型层序地层构型.充分利用钻井、测井和高分辨率三维地震等资料,运用层序地层学和沉积盆地分析相关理论和方法,系统地研究了"异迁移"型层序构型的特征和成因机制.结果表明,南堡凹陷高北地区沙河组为3个二级层序、7个三级层序(SQ1~SQ7),在地震剖面上呈现出独特的"跷跷板式"交替增厚的横向叠加特征.其中,SQ1~SQ2层序主要发育于盆地西侧,SQ3~SQ4层序在盆地两侧均匀发育,SQ5~SQ7层序主要发育于盆地东侧.多重因素相互叠加形成了这种独特的层序构型:(1)幕式运动造成边界断层活动性发生东西转换,从而导致层序沉积中心自西向东大范围迁移;(2)不同时期板块活动引起区域应力场的方向发生顺时针旋转,使得控凹断层由早期的NW-SE向逐渐变为N-S向;(3)不同类型的断层组合样式也影响着沉积中心发育的位置和规模,从而导致了研究区沙河街组时期层序发生大范围的迁移."异迁移"型层序在侧向迁移过程中,不同层序内发育的沉积相特征和充填样式均发生自西向东规律性的转移,提出"异迁移"型层序构型成因机制的研究可以更好地为幕式构造活动背景下陆相断陷湖盆沉积层序演化提供新的思路和见解. 展开更多
关键词 南堡凹陷 高北地区 幕式构造活动 “异迁移”型层构型 沉积
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Microdissection of Haynaldia villosa Telosome 6VS and Cloning of Species-specific DNA Sequences 被引量:3
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作者 孔凡晶 陈孝 +4 位作者 马有志 辛志勇 李连成 张增艳 林志姗 《Acta Botanica Sinica》 CSCD 2002年第3期307-313,共7页
The material T240_6 derived from SC 2 young embryo of the combination CA9211/RW15 (6D/6V alien substitution) was telosomic substitution line of 6VS identified by GISH (genomic in situ hybridization) analysis. The 6V... The material T240_6 derived from SC 2 young embryo of the combination CA9211/RW15 (6D/6V alien substitution) was telosomic substitution line of 6VS identified by GISH (genomic in situ hybridization) analysis. The 6VS was microdissected with a needle and transferred into a 0.5 mL Ep tube. In the 'single tube', all the subsequence steps were conducted. After two round of LA (Linker adaptor)_PCR amplification, the size of PCR bands ranged from 100 to 3 000 bp, with predominate bands 600-1 500 bp. The products were confirmed by Southern blotting analysis using Haynaldia villosa (L.) Schur. genomic DNA labeled with 32 P as probe. The PCR products were purified and ligated into clone vector-pGEM_T easy vector. Then, the plasmids were transformed into competence E. coli JM109 with cool CaCl 2. It was estimated that there were more than 17 000 white clones in the library. The size of insert fragments distributed from 100-1 500 bp, with average of 600 bp. Using H. villosa genomic DNA as probe, dot blotting results showed that 37% clones displayed strong and medium positive signals, and 63% clones had faint or no signals. It is demonstrated that there were about 37% repeat sequence clones and 67% single/unique sequence clones in the library. Eight H. villosa_specific clones were screened from the library, and two clones pHVMK22 and pHVMK134 were used for RFLP analysis and sequencing. Both of them were H. villosa specific clones. The pHVMK22 was a unique sequence clone, and the pHVMK134 was a repeat sequence clone. When the pHVMK22 was used as a probe for Southern hybridization, all the powdery mildew resistance materials showed a special band of 2 kb, while all the susceptible ones not. The pHVMK22 may be applied to detect the existence of Pm21. 展开更多
关键词 microdissection and microcloning of chromosome Haynaldia villosa genomic in situ hybridization alien substitution of telosome species_specific DNA sequences RFLP
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Approach to evaluating exception handling of programs
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作者 姜淑娟 徐宝文 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期524-528,共5页
To solve the problems that the exception handling code is hard to test and maintain and that it affects the robustness and reliability of software, a method for evaluating the exception handling of programs is present... To solve the problems that the exception handling code is hard to test and maintain and that it affects the robustness and reliability of software, a method for evaluating the exception handling of programs is presented. The exception propagation graph (EPG) that describes the large programs with exception handling constructs is proposed by simplifying the control flow graph and it is applied to a case to verify its validity. According to the EPG, the exception handling code that never executes is identified; the points that are the most critical to controlling exception propagation are found; and the irrational exception handling code is corrected. The constructing algorithm for the EPG is given; thus, this provides a basis for automatically constructing the EPG and automatically correcting the irrational exception handling code. 展开更多
关键词 software robustness exception handling exception propagation evaluating program control flow graph
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Sequence Variation in the Gp120 region of SHIV-CN97001 during in vivo Passage 被引量:6
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作者 Qiang LIU Gui-bo YANG +4 位作者 Yue MA Chen-li QIU Jie-jie DAI Hui XING Yi-ming SHAO 《Virologica Sinica》 SCIE CAS CSCD 2008年第1期8-14,共7页
SHIV-CN97001 played an important role in assessing the immune effect and strategy of the AIDS vaccine which included genes of the predominant prevalent HIV-1 strain in China. In this study, SHIV-CN97001 was in vivo pa... SHIV-CN97001 played an important role in assessing the immune effect and strategy of the AIDS vaccine which included genes of the predominant prevalent HIV-1 strain in China. In this study, SHIV-CN97001 was in vivo passaged serially to construct pathogenic SHIV-CN97001/rhesus macaques model. To identify variation in the gp120 region of SHIV-CN97001 during passage, the fragments of gp120 gene were amplified by RT-PCR from the plasma of SHIV-CN97001 infected animals at the peak viral load time point and the gene distances (divergence, diversity) were calculated using DISTANCE. The analysis revealed that the genetic distances of SHIV-CN97001 in the third passage animals were the highest during in vivo passage. It had a relationship between viral divergence from the founder strain and viral replication ability. The nucleic acid sequence of the V3 region was highly conservative. All of the SHIV-CN97001 strains had V3 loop central motif (GPGQ) and were predicted to be using CCR5 co-receptor on the basis of the critical amino acids within V3 loop. These results show that there was no significant increase in the genetic distance during serial passage, and SHIV-CN97001 gp120 gene evolved toward ancestral states upon transmission to a new host. This could partly explain why there was no pathogenic viral strain obtained during in vivo passage. 展开更多
关键词 SHIV PASSAGE GP120 VARIATION Sequence analysis
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A Novel Training Sequence Applied to DCS-Based Channel Estimation 被引量:2
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作者 Weizhang Xu Xinle Yu +2 位作者 Yanfei Li Lu Si Zhanxin Yang 《China Communications》 SCIE CSCD 2018年第11期70-78,共9页
Studies have indicated that the distributed compressed sensing based(DCSbased) channel estimation can decrease the length of the reference signals effectively. In block transmission, a unique word(UW) can be used as a... Studies have indicated that the distributed compressed sensing based(DCSbased) channel estimation can decrease the length of the reference signals effectively. In block transmission, a unique word(UW) can be used as a cyclic prefix and reference signal. However, the DCS-based channel estimation requires diversity sequences instead of UW. In this paper, we proposed a novel method that employs a training sequence(TS) whose duration time is slightly longer than the maximum delay spread time. Based on proposed TS, the DCS approach perform perfectly in multipath channel estimation. Meanwhile, a cyclic prefix construct could be formed, which reduces the complexity of the frequency domain equalization(FDE) directly. Simulation results demonstrate that, by using the method of simultaneous orthogonal matching pursuit(SOMP), the required channel overhead has been reduced thanks to the proposed TS. 展开更多
关键词 jointly sparse channel estimation distributed compressed sensing (DCS) simul-taneous orthogonal matching pursuit (SOMP) training sequence (TS) unique word (UW) frequency domain equalization (FDE)
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Structural Variation Analysis of Mutated Nannochloropsis oceanica Caused by Zeocin Through Genome Re-Sequencing 被引量:3
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作者 LIN Genmei ZHANG Zhongyi +2 位作者 GUO Li DING Haiyan YANG Guanpin 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1225-1230,共6页
Zeocin can cause double strand breaks of DNA and thus may be employed as a mutagen. In this study, two strains of Nannochloropsis oceanica, the wild and the Zeocin-tolerant strains, were re-sequenced to verify such fu... Zeocin can cause double strand breaks of DNA and thus may be employed as a mutagen. In this study, two strains of Nannochloropsis oceanica, the wild and the Zeocin-tolerant strains, were re-sequenced to verify such function of Zeocin, The results showed that Zeocin can mutate the N. oceanica genome and cause the structural variation. Zeocin either swept away or selected the alleles of genes functioning in ubiquitin-mediated proteolysis, alpha-linolenic acid metabolism, ascorbate and aldarate metabolism, ribosome biogenesis, and circadian rhythm, indicating that N. oceanica may have adjusted its metabolic performances for protein, carbohydrate, and lipid, and changed its ribosome biosynthesis and living rhythm to survive in Zeocin containing medium. In addition, Zeocin caused mutation may have influenced the expression of a set of tanscription factors. It was concluded that Zeocin effectively caused the structural variation of the genome of N. oceanica, and forced the microalgae to select out the alleles of a set of genes around these variations in order to adapt to Zeocin containing medium. Further studies on the genetic basis of the phenotypic adaptation of this haploid and asexual microalga and the application of Zeocin to its genetic improvement are very important. 展开更多
关键词 Nannochloropsis oceanica Zeocin MUTATION genome re-sequencing structural variation
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Analysis of the Flanking Sequence and EventSpecific Detection of Transgenic Line W-4 of Brassica napus 被引量:1
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作者 陈松 申爱娟 +1 位作者 周晓婴 戚存扣 《Agricultural Science & Technology》 CAS 2014年第7期1089-1094,共6页
The genetically modified high-oleic rapeseed (Brassica napus L.) line W-4 was obtained by transforming a binary vector which harbored an inverted repeat expression cassette of fad2 gene into the rapeseed cultivar We... The genetically modified high-oleic rapeseed (Brassica napus L.) line W-4 was obtained by transforming a binary vector which harbored an inverted repeat expression cassette of fad2 gene into the rapeseed cultivar Westar.The transformation was mediated by Agrobacterium.The flanking sequences to both the left and right borders of T-DNA insertion site were amplified by thermal asymmetric interlaced PCR (TAIL-PCR) from the genomic DNA of the transgenic rapeseed line W-4.The flanking sequences to the right border was 290 bp in length and the nucleotide composition was 31.27% for G+C content while 68.73% for A+T content.The flanking sequence to the left border was 365 bp in length and the G+C content was 32.6% and the A+T content was 67.4%,indicating that the T-DNA was integrated in the A/T-rich region.Further more,sequence alignment analysis showed a deletion of 62 bp including the right border of pCNFIRnos and the integration of the whole left border except a change of G to A.That was to say,the integration of the T-DNA in the transgenic line W-4 not involved in the vector sequences.Based on both flanking sequences as well as the left and right borders of the T-DNA sequences,two pairs of specific primers TLF/TLR and TRF/TRR were designed.Using the primers the event-specific PCR detection method for transgenic rapeseed line W-4 was established.By the PCR,two fragments of 485 and 405 bp were amplified from the W-4 genomic DNA as expected,while no products were amplified from the genomic DNA of other transgenic rapeseed lines and non-transgenic rapeseed line.And by the PCR it is possible to detect the W-4 genomic DNA from a mixed sample of genomic DNA.The limit of the detection for the qualitative PCR assay was 0.1%.The method developed in this work is highly specific,sensitive and suitable for event-specific detection of the transgenic rapeseed line W-4. 展开更多
关键词 Transgenic rapeseed Flanking sequences Event-specific detection
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Analysis of molecular variation in porcine reproductive and respiratory syndrome virus in China between 2007 and 2012 被引量:2
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作者 Yuhang Cao Hongsheng Ouyang +4 位作者 Mingjun Zhang Fuwang Chen Xin Yang Daxing Pang Linzhu Ren 《Virologica Sinica》 SCIE CAS CSCD 2014年第3期183-188,共6页
In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics... In the present study, 89 porcine reproductive and respiratory syndrome virus(PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics of these isolates were analyzed based on the sequences of non-struc-tural protein 2(Nsp2) and glycoprotein 5(GP5). The genetic variations of the isolates were also compared with six representative strains. The results showed that a high degree of genetic diversity exists among the PRRSV population in China. Highly pathogenic PRRSV isolates, with a discon-tinuous deletion of a 30 amino acid residue in the Nsp2 region, remained the most dominant virus throughout 2007–2012 in China. Owing to the extensive use of representative vaccine strains, natu-ral recombination events occurred between strains. Three isolates – HH08, DY, and YN-2011 – were more closely related to vaccine strains than the other isolates. Both YN-2011 and DY were the evolu-tionary products of recombination events between strains SP and CH-1R. The results of the present study provide useful information for the epidemiology of PRRSV as well as for vaccine development. 展开更多
关键词 porcine reproductive and respiratory syndrome virus(PRRSV) open reading frame(ORF) non-structural protein 2(Nsp2) glycoprotein 5(GP5) recombination
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Novel mutations and sequence variants in exons 3-9 of human T Cell Factor-4 gene in sporadic rectal cancer patients stratified by microsatellite instability 被引量:1
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作者 Wen-Jian Meng Ling Wang +9 位作者 Chao Tian Yong-Yang Yu Bing Zhou Jun Gu Qing-Jie Xia Xiao-Feng Sun Yuan Li Rong Wang Xue-Lian Zheng Zong-Guang Zhou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第27期3747-3751,共5页
AIM: To establish the role of human T Cell Factor-4 (hTCF-4) gene exons 3-9 mutation status in association with sporadic rectal cancer with microsatellite instability (MSI). METHODS: Microsatellite markers were ... AIM: To establish the role of human T Cell Factor-4 (hTCF-4) gene exons 3-9 mutation status in association with sporadic rectal cancer with microsatellite instability (MSI). METHODS: Microsatellite markers were genotyped in 93 sporadic rectal cancer patients. Eleven cases were found to be high-frequency MSI (MSI-H). Sequence analysis of the coding region of the exons 3-9 of hTCF-4 gene was carried out for the 11 MSI-H cases and 10 controls (5 microsatellite stability (MSS) cases and 5 cases with normal mucosa). The sequencing and MSI identification were used. RESULTS: Several novel mutations and variants were revealed. In exon 4, one is a 4-position continuous alteration which caused amino acid change from Q131T and S132I (391insA, 392 G 〉 A, 393 A 〉 G and 395delC) and another nucleotide deletion (395delC) is present in MSI-H cases (5/10 and 4/10, respectively) but completely absent in the controls.CONCLUSION: Novel mutations in exon 4 of hTCF-4 gene were revealed in this study, which might be of importance in the pathogenesis of sporadic rectal cancer patients with MSI-H. 展开更多
关键词 hTCF-4 Sporadic rectal cancer Microsatellite instability Mutation analysis
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The Appearance of Ulva laetevirens(Ulvophyceae, Chlorophyta) in the Northeast Coast of the United States of America 被引量:2
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作者 MAO Yunxiang Jang Kyun Kim +1 位作者 Roderick Wilson Charles Yarish 《Journal of Ocean University of China》 SCIE CAS 2014年第5期865-870,共6页
Introduced species may outcompete or hybridize with native species, resulting in the loss of native biodiversity or even alteration of ecosystem processes. In this study, we reported an alien distromatic Ulva species,... Introduced species may outcompete or hybridize with native species, resulting in the loss of native biodiversity or even alteration of ecosystem processes. In this study, we reported an alien distromatic Ulva species, which was found in an embayment(Holly Pond) connected with Long Island Sound, USA. The morphological and anatomical observations in combination with molecular data were used for its identification to species. Anatomy of collected specimens showed that the cell shape in rhizoidal and basal regions was round and the marginal teeth along the basal and median region were not found. These characteristics were primarily identical to the diagnostic characteristics of Ulva laetevirens Areschoug(Chlorophyta). The plastid-encoding tufA and nucleus-encoding ITS1 were used for its molecular identification. Phylogenetic analysis for the tufA gene placed the specimens from Holly Pond in a well-supported clade along with published sequences of U. laetevirens identified early without any sequence divergence. In ITS tree, the sample also formed well-supported clades with the sequences of U. laetevirens with an estimated sequence divergence among the taxa in these clades as low as 1%. These findings confirmed the morpho-anatomical conclusion. Native to Australia, this species was reported in several countries along the Mediterranean coast after the late of 1990 s. This is the first time that U. laetevirens is found in the northeast coast of United States and the second record for Atlantic North America. 展开更多
关键词 Ulva laetevirens Areschoug introduced seaweed Long Island Sound USA ITS TUFA
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Temporal variability of temperature-nitrate relationship in a coastal region
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作者 殷建平 林立 +1 位作者 王友绍 杜建伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期879-885,共7页
The inverse relationship between nitrate and temperature(N-T relationship) has been used to estimate new production from remotely sensed sea surface temperature at the regional or global scale of oceans. This study ai... The inverse relationship between nitrate and temperature(N-T relationship) has been used to estimate new production from remotely sensed sea surface temperature at the regional or global scale of oceans. This study aimed to develop a time-series model of the N-T relationship from automated, continuous hourly observations over two years on the coast of Halifax, Canada. The model demonstrated time-series variability of the N-T relationship at a coastal station on the Nova Scotia Shelf, with adjusted R 2 =0.999 4 and RMSE=0.025 7. The maximum residual value was 0.077. The annual temperature variations described a sine curve, and daily, weekly, and monthly variations fluctuated within the normal ranges, controlled by the local climate. The annual variation of nitrate concentration formed nearly a sine curve. Heavy or longlasting rainfall increased nitrate concentration by 4 to 30-fold in 24 h, and then the increased nitrogen was quickly depleted by phytoplankton growth in 10 to 48 h. In general, biological activity was a key factor in causing nitrate concentration change, dependent mainly on seawater temperature. The power function of the N-T relationship observed in our study area could be used to quickly estimate sea surface nitrate concentration, in combination with temperature data obtained by remote sensing. 展开更多
关键词 sea surface temperature sea surface nitrate nitrate and temperature (N-T relationship) model Halifax Canada
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Diagnosis of stator faults in induction motor based on zero sequence voltage after switch-off
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作者 Jia-qiang YANG Jin HUANG Tong LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第2期165-172,共8页
To improve the accuracy of the stator winding fault diagnosis in induction motor,a new diagnostic method based on the Hilbert-Huang transform(HHT)was proposed.The ratio of fundamental zero sequence voltage to positive... To improve the accuracy of the stator winding fault diagnosis in induction motor,a new diagnostic method based on the Hilbert-Huang transform(HHT)was proposed.The ratio of fundamental zero sequence voltage to positive sequence voltage after switch-off was selected as the stator fault characteristic,which could effectively avoid the influence of the supply unbalance and the load fluctuation,and directly represent the asymmetry in the stator.Using the empirical mode decomposition(EMD)based on HHT,the zero sequence voltage after switch-off was decomposed and the fundamental component was extracted.Then,the fault characteristic can be acquired.Experimental results on a 4-kW induction motor demonstrate the feasibility and effectiveness of this method. 展开更多
关键词 Induction motor Stator fault diagnosis Hilbert-Huang transform (HHT) Zero sequence voltage Empirical modedecomposition (EMD)
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Effects of friction variability on isolation performance of rolling-spring systems 被引量:1
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作者 魏标 王鹏 +3 位作者 杨添涵 戴公连 蒋丽忠 文颖 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第1期233-239,共7页
By taking a rolling-spring isolation system as the study object, the effects of the non-uniform distribution of rolling friction coefficient on its isolation performance were analyzed by a compiled computer program. T... By taking a rolling-spring isolation system as the study object, the effects of the non-uniform distribution of rolling friction coefficient on its isolation performance were analyzed by a compiled computer program. The results show that the errors associated with the structural maximum relative displacement, acceleration and residual displacement due to ignoring the friction variability sequentially grow. This rule is weakened by the spring action, however, the unreasonable spring constant will cause sympathetic vibration. Under the condition of large friction variability, in the calculation of the structural maximum relative displacement and acceleration, the friction variability should be considered. When the structural residual displacement is concerned, the variability of rolling friction coefficient should be fully considered regardless of the friction variability. 展开更多
关键词 rolling-spring structure seismic isolation rolling friction seismic performance
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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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