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基于多源异构时间序列特征融合的电力窃电检测的研究
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作者 闵文浩 刘天羽(指导) 《上海电机学院学报》 2024年第5期262-267,共6页
长期以来,供电企业一直面临着电能被窃这一严重问题。为了有效应对这一难题,本文提出了一种基于多源异构时间序列特征融合的电力窃电检测方法。首先,通过特征分析,选择气象、日历、家庭属性等多源异构数据并构建多特征图结构;其次,利用... 长期以来,供电企业一直面临着电能被窃这一严重问题。为了有效应对这一难题,本文提出了一种基于多源异构时间序列特征融合的电力窃电检测方法。首先,通过特征分析,选择气象、日历、家庭属性等多源异构数据并构建多特征图结构;其次,利用图神经网络对多源异构数据进行时空建模,并引入注意力机制聚焦关键的时空特征。实验表明:与单一数据源相比,多源特征融合可显著提升检测性能,所提出的模型优于其他对比模型,为构建高效的电力窃电检测系统提供了新思路。 展开更多
关键词 窃电 异构时间序列 特征融合 图神经网络 注意力机制
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新源、和静交界ML6.8地震序列的应力降和震源机制研究 被引量:7
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作者 刘建明 王琼 +4 位作者 刘杰 邓菲 向元 杨文 李金 《中国地震》 北大核心 2016年第1期28-39,共12页
采用新疆区域台网记录的2012年6月30日新源、和静交界M_L6.8地震序列的数字波形资料,研究分析了余震序列应力降的变化特征及其地震序列震源机制的相关性。采用波谱分析方法和Brune震源模型,计算了新源、和静交界M_L6.8地震序列震源参数... 采用新疆区域台网记录的2012年6月30日新源、和静交界M_L6.8地震序列的数字波形资料,研究分析了余震序列应力降的变化特征及其地震序列震源机制的相关性。采用波谱分析方法和Brune震源模型,计算了新源、和静交界M_L6.8地震序列震源参数、地震序列中不同事件在相同台站的体波零频震源谱值、地震谱振幅相关系数;并对地震序列震源机制解进行聚类分组。结果表明:①在余震序列平静阶段,应力降呈平稳态势,强余震前应力降出现升高-回落变化过程;②滑动平均谱振幅相关系数在主震后发散,表明余震的震源机制解与主震的相关性降低;③震源机制解聚类分组结果显示,M_L6.8地震序列主要以走滑型地震为主,主压应力轴呈近NS向,与近NS向的构造应力场结果基本一致,一定程度上显示了地震前天山中段受NS向水平挤压应力作用明显;④震级、震源机制演化表明,强余震前震源机制解表现较好的一致性,显示了区域应力场控制作用增强,对后续强余震发生具有预测意义。 展开更多
关键词 、和静交界ML6.8地震序列 应力降 机制相关系数 体波谱振幅 聚类分组
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基于SSTDR的飞机电缆故障定位脉冲序列源设计 被引量:6
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作者 周训春 肖楚琬 +1 位作者 刘勇 王诚成 《国外电子测量技术》 2018年第12期91-96,共6页
发射信号是影响SSTDR在飞机电缆故障检测与定位中准确度和精度的关键因素,为实现高精度电缆故障检测,根据飞机电缆特点设计脉冲序列源。脉冲序列源根据飞机电缆测试范围短、精度要求高的特点,采用FPGA结合高速DDS芯片生成ns级BPSK调制... 发射信号是影响SSTDR在飞机电缆故障检测与定位中准确度和精度的关键因素,为实现高精度电缆故障检测,根据飞机电缆特点设计脉冲序列源。脉冲序列源根据飞机电缆测试范围短、精度要求高的特点,采用FPGA结合高速DDS芯片生成ns级BPSK调制的脉冲序列,采用放大电路实现脉冲信号幅值可调,并利用接口电路实现阻抗匹配。经过对脉冲序列源性能测试和电缆实测,测试结果表明序列源能产生幅值为3-7 V,码片宽度为20-60 ns,长度为7-127可调的PN码;该序列源测试盲区控制在2m以内,测试精度能达到0.5 m,满足飞机电缆故障精确定位的需求。 展开更多
关键词 频谱时域反射法(SSTDR) 序列脉冲 PN码 故障定位
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来自中国云南野生稻的抗稻瘟病遗传资源(英文) 被引量:4
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作者 杨明挚 程在全 +3 位作者 陈善娜 钱君 徐玲玲 黄兴奇 《植物生理与分子生物学学报》 CAS CSCD 北大核心 2007年第6期589-595,共7页
与Pi-ta^-等位基因相比,含有Pi-ta^+等位基因的栽培稻具有抗稻瘟病特性。本研究用基因序列分析的方法检测了来自云南的不同栽培稻品种以及不同类型和来源的普通野生稻种和非洲长雄蕊野生稻种中的Pi-ta基因,发现Pi-ta基因在稻属植物中高... 与Pi-ta^-等位基因相比,含有Pi-ta^+等位基因的栽培稻具有抗稻瘟病特性。本研究用基因序列分析的方法检测了来自云南的不同栽培稻品种以及不同类型和来源的普通野生稻种和非洲长雄蕊野生稻种中的Pi-ta基因,发现Pi-ta基因在稻属植物中高度保守,但Pi-ta^+等位基因的存在极其稀有。在所检测的栽培稻和野生稻中仅有来源于云南景洪的直立型普通野生稻中含有Pi-ta^+等位基因。而与Pi-ta基因相比,另一个水稻抗稻瘟病基因Pib,经部分同源序列克隆及测序发现该基因在不同野生稻中的变异较大。在所克隆的不同野生稻Pib基因同源序列中,也只有来源于直立型普通野生稻的序列能按该基因的开放阅读框进行正常翻译。对不同类型普通野生稻的抗稻瘟病能力的初步鉴定结果表明,直立型普通野生稻对供试的本地稻瘟病生理小种具有较强抗性,其抗性可能源于所含的Pi-ta^+等位基因及可能有功能的Pib基因。由于普通野生稻与栽培稻同属AA基因组型,因此,云南直立型普通野生稻可通过杂交育种或基因工程途径用于栽培稻的抗稻瘟病性能改良。 展开更多
关键词 直立型普通野生稻 Pi-ta^+等位基因 Pib基因同 源序列 抗稻瘟病遗传资
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基于DDS与DSP Builder设计双通道正弦信号源的全新方法
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作者 常铁原 刘娜 陈文军 《电脑知识与技术》 2005年第12期201-203,共3页
介绍了设计双通道正弦信号发生器,并能实现频率、幅度以及相位均可调得全新方法。该方法基于直接数字频率合成技术(DDs),应用Altera公司推出的DSP Builder和QuartusⅡ软件设计并进行了仿真实现。
关键词 正弦信号:直接数字序列合成 QuartusⅡ FPGA
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Physical Mapping of the Sequences Homologous to Disease Resistance Genes myb1 and NDR1 in Maize 被引量:9
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作者 宁顺斌 宋运淳 +2 位作者 王玲 魏文辉 刘立华 《Acta Botanica Sinica》 CSCD 2000年第6期605-610,共6页
Using fluorescence in situ hybridization, the authors investigated the homology between three plant species, maize (Zea mays L.) and tobacco (Nicotiana tabacum L.), maize and Arabidopsis thaliana (L.) Heynh. at cy... Using fluorescence in situ hybridization, the authors investigated the homology between three plant species, maize (Zea mays L.) and tobacco (Nicotiana tabacum L.), maize and Arabidopsis thaliana (L.) Heynh. at cytogenetic level using two probes corresponding to functional disease resistance genes myb1 and NDR1 in Arabidopsis and tobacco respectively. The hybridization signals of the tested probes were detected in maize chromosomes 8 and 5 respectively, and the single location of each of the two probes showed only single copy of them in maize genome. The results provided a valuable insight into searching for genes associated with programmed cell death in plants using heterologous probe with comparative genetic approach. In addition, the improvements of FISH technique using heterologous probes were discussed. 展开更多
关键词 hypersensitive response programmed cell death comparative genetics fluorescence in situ hybridization MAIZE
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Isolation and Characterization of Mlo and NBS-LRR-like Gene Sequences in Wheat 被引量:5
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作者 李爱丽 孔秀英 +2 位作者 周荣华 马峙英 贾继增 《Acta Botanica Sinica》 CSCD 2003年第4期472-478,共7页
Based on both cDNA sequence of barley powdery mildew resistance control element Mlo and DNA sequence of the known putative disease resistance gene from Triticum monococcum L., we designed some primers to amplify resis... Based on both cDNA sequence of barley powdery mildew resistance control element Mlo and DNA sequence of the known putative disease resistance gene from Triticum monococcum L., we designed some primers to amplify resistant homologous sequences in the near isogenic lines (NILs) of powdery mildew resistance using RT-PCR method. Two expressed cDNA fragments were isolated from wheat genome. One showed 83% homology to the Mlo gene of barley. The other contained two possible open reading frames (ORFs). NBS conservative domains 2, 3 of disease resistance gene and 13 LRR structures similar to rice Pib protein terminal were found respectively in the two ORFs. It indicated that the latter fragment belongs to NBS-LRR-like genes. The obvious difference of RT-PCR products was observed between the before challenged and the challenged for 72 h by Blumeria graminis f. sp. tritici, which, implied that this sequence could be associated with disease resistance of wheat. Using nulli-tetrasomic lines of 'Chinese Spring', the NBS-LRR-like gene had been located on chromosome 1D. 展开更多
关键词 MLO NBS-LRR cDNA cloning NIL RGA
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Cloning and Analysis of a Disease Resistance Gene Homolog from Soybean 被引量:3
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作者 王邦俊 张志刚 +4 位作者 李学刚 王永军 贺超英 张劲松 陈受宜 《Acta Botanica Sinica》 CSCD 2003年第7期864-870,共7页
Conserved domains e.g. nucleotide binding site (NBS) were found in several cloned plant disease resistance genes. Based on the NBS domain, resistance gene analogs (RGAs) have been isolated previously and were used as ... Conserved domains e.g. nucleotide binding site (NBS) were found in several cloned plant disease resistance genes. Based on the NBS domain, resistance gene analogs (RGAs) have been isolated previously and were used as probes to screen a soybean (Glycine max L. Merr.) cDNA library. A full-length cDNA, KR3, was obtained by screening the library and rapid amplification of cDNA ends (RACE) method. Sequence analysis revealed that the cDNA is 2 353 bp in length and the open reading frame (ORF) codes for a polypeptide of 636 amino acids with a Toll-Interleukin-1 receptor (TIR) and a NBS domain. Sequence alignment showed that it was similar to N gene of tobacco. The phylogenetic tree analysis of R proteins with NBS from higher plants was performed. The KR3 gene has low copies in soybean genome and its expression was induced by exogenous salicylic acid (SA). 展开更多
关键词 disease resistance gene homolog nucleotide binding site Toll-Interleukin-1 receptor SOYBEAN
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Cloning and Analysis of NBS-LRR Type Resistance Gene Analogues in Sweet Potato (Ipomoea batatas) 被引量:7
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作者 林巧玲 曾会才 《Agricultural Science & Technology》 CAS 2008年第2期76-80,共5页
The degenerate primers were designed based on the conserved NBS-LRR motifs among the known disease-resistance genes. A fragment of about 500 bp was amplified from genomic DNA of sweet potato using the specifically des... The degenerate primers were designed based on the conserved NBS-LRR motifs among the known disease-resistance genes. A fragment of about 500 bp was amplified from genomic DNA of sweet potato using the specifically designed degenerate primers. After cloning and sequencing, 20 NBS-LRR type of disease-resistance gene analogue (RGAs) in sweet potato were observed. The deduced amino acid sequence of DNA fragment contains the conserved motifs of NBS-LRR type RGAs, such as P-loop, Kinase-2α, Kinase-3α and GLPL domain. The 20 RGAs could be sorted into two subclasses, namely TIR- NBS-LRR type and non-TIR-NBS-LRR type. Compared with the known resistance genes including N, L6 and M, the percentages of homologous amino acid sequence in 10 TIR-NBS-LRR range between 21% -44%. While other 10 non-TIR-NBS-LRR assume 15% -46% homology with the known resistance genes (Prf, RPM1, RPS2, etc. ). Consequently the RGAs may further be used as molecular marker for screening the candidate disease-resistance genes in sweet potato. 展开更多
关键词 Sweet potato NBS-LRR analogs R genes
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Monopterus albus Contains a Sequence Homolous to the 5'cDNA of the Rat Tyrosine Kinase Receptor-encoding Gene, ptk3
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作者 周荣家 余其兴 程汉华 《Developmental and Reproductive Biology》 1996年第1期13-16,共4页
From the. genome of the Rice-field Eel,Monopterus alubs partial DNA sequence has been obtained that shows homology to the 5'cDNA sequence of the gene encoding rat tyrosine kinase receptor ptk3. Southern blots reve... From the. genome of the Rice-field Eel,Monopterus alubs partial DNA sequence has been obtained that shows homology to the 5'cDNA sequence of the gene encoding rat tyrosine kinase receptor ptk3. Southern blots revealed identical hybridization patterns in both sex. 展开更多
关键词 signal transduction SRY FISH rice-field eel
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中继卫星S/Ka双频地面站天线共用跟踪接收机 被引量:2
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作者 柯树人 施浒立 《飞行器测控学报》 2005年第6期63-68,共6页
论述了Ka频段圆波导TE11和TE21模自跟踪体制和S频段正十字排列四喇叭自跟踪体制共用两信道自跟踪接收机问题.导出了来波及地面天线S频段和、差信道极化特性引起的角误差电压的交叉耦合系数公式.还可以进一步使S/Ka两个频段共用一套能跟... 论述了Ka频段圆波导TE11和TE21模自跟踪体制和S频段正十字排列四喇叭自跟踪体制共用两信道自跟踪接收机问题.导出了来波及地面天线S频段和、差信道极化特性引起的角误差电压的交叉耦合系数公式.还可以进一步使S/Ka两个频段共用一套能跟踪(直接序列)扩频信号源的伪单脉冲(单信道单脉冲)自跟踪接收机. 展开更多
关键词 差信号合成 两信道跟踪接收机 角误差电压交叉耦合 伪单脉冲跟踪接收机 直接序列扩频信号
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Genome-wide Detection and Analysis of Alternative Splicing for Nucleotide Binding Site-Leucine-Rich Repeats Sequences in Rice
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作者 顾连峰 郭荣发 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第3期247-257,共11页
Alternative splicing is a major contributor to genomic complexity and proteome diversity, yet the analysis of alternative splicing for the sequence containing nucleotide binding site and leucine-rich repeats (NBS-LRR... Alternative splicing is a major contributor to genomic complexity and proteome diversity, yet the analysis of alternative splicing for the sequence containing nucleotide binding site and leucine-rich repeats (NBS-LRR) domain has not been explored in rice (Oryza sativa L.). Hidden Markov model (HMM) searches were performed for NBS-LRR domain. 875 NBS-LRR-encoding sequences were obtained from the Institute for Genomic Research (TIGR). All of them were used to blast Knowledge-based Oryza Molecular Biological Encyclopaedia (KOME), TIGR rice gene index (TGI), and Universal Protein Resource (UniProt) to obtain homologous full-length cDNAs (FL-cDNAs), tentative consensus sequences, and protein sequences. Alternative splicing events were detected from genomic alignment of FL-cDNAs, tentative consensus sequences, and protein sequences, which provide valuable information on splice variants of genes. These sequences were aligned to the corresponding BAC sequences using the Spidey and Sim4 programs and each of the proteins was aligned by tBLASTn. Of the 875 NBS-LRR sequences, 119 (13.6%) sequences had alternative splicing where multiple FL-cDNAs, TGI sequences and proteins corresponded to the same gene. 71 intron retention events, 20 exon skipping events, 16 alternative termination events, 25 alternative initiation events, 12 alternative 5' splicing events, and 16 alternative 3' splicing events were identified. Most of these alternative splices were supported by two or more transcripts. The data sets are available at http://www.bioinfor.org. Furthermore, the bioinformatics analysis of splice boundaries showed that exon skipping and intron retention did not exhibit strong consensus. This implies a different regulation mechanism that guides the expression of splice isoforms. This article also presents the analysis of the effects of intron retention on proteins. The C-terminal regions of alternative proteins turned out to be more variable than the N-terminal regions. Finally, tissue distribution and protein localization of alternative splicing were explored. The largest categories of tissue distributions for alternative splicing were shoot and callus. More than one-thirds of protein localization for splice forms was plasma membrane and cytoplasm. All the NBS-LRR proteins for splice forms may have important function in disease resistance and activate downstream signaling pathways. 展开更多
关键词 alternative splicing BIOINFORMATICS NBS-LRR homologous sequence RICE
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Partial Sequence Analysis of Mitochondrial COI Gene of the Chinese Shrimp,Fenneropenaeus Chinensis 被引量:6
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作者 GAOTianxiang LIJian +1 位作者 WANGQingyin LIUJinxian 《Journal of Ocean University of Qingdao》 2003年第2期167-170,共4页
Eight hundred and thirty eight base pair fragment of mitochondrial COI gene of wild and cultured populations (CP1, CP4, CP5 and CP6) of Fenneropenaeus chinensis was amplified and sequenced. The A, T, G and C contents ... Eight hundred and thirty eight base pair fragment of mitochondrial COI gene of wild and cultured populations (CP1, CP4, CP5 and CP6) of Fenneropenaeus chinensis was amplified and sequenced. The A, T, G and C contents of the sequence were 235bp(28.0%), 307bp(36.6%), 138bp(16.5%) and 158bp(18.9%), respectively. Furthermore, 556bp fragment of the sequence was used to discuss the phylogenetic relationship among 14 Penaeidae species using Alpheus armillatus as the outgroup. From the molecular phylogenetic tree constructed by neighbor-joining method, we obtained three large shrimp groups:Farfantepenaeus, Litopenaeus and Fenneropenaeus group. The results also indicated that there were a closer genetic relationships between F. aztecus and F. paulensis, L. schmitti and L. setiferus, F. indicus and F. merguiensis, and the genus Farfantepenaeus was closer to Litopenaeus. 展开更多
关键词 Fenneropenaeus chinensis cytochrome oxidase subunit 1(COI) DNA sequence PENAEIDAE phylogeny
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基于双重正则矩阵分解的缺失数据恢复 被引量:3
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作者 刘歌 芮国胜 田文飚 《系统工程与电子技术》 EI CSCD 北大核心 2021年第5期1191-1197,共7页
针对多源时间序列缺失数据恢复问题,提出一种基于双重正则矩阵分解的恢复方法。该方法在多源时间序列矩阵分解的基础上,利用时间序列的平滑性构建时间序列隐含因子的二阶差分正则项,同时引入反映数据内部结构的图拉普拉斯正则项对传感... 针对多源时间序列缺失数据恢复问题,提出一种基于双重正则矩阵分解的恢复方法。该方法在多源时间序列矩阵分解的基础上,利用时间序列的平滑性构建时间序列隐含因子的二阶差分正则项,同时引入反映数据内部结构的图拉普拉斯正则项对传感器隐含因子进行约束,并在图拉普拉斯矩阵获取过程中设计了一种联合数据本身的相似度和数据变化趋势相似度的双重皮尔逊相似策略,构造数据内部的最相似图。最后,将双正则项统一于矩阵分解的框架中,利用梯度下降法实现目标函数的优化,数据实验中分别采用合成数据和真实数据验证了算法的有效性。 展开更多
关键词 时间序列 数据缺失 矩阵分解 图拉普拉斯正则化
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Molecular Characterization of Viral G Gene in Emerging and Re-emerging Areas of Rabies in China, 2007 to 2011 被引量:20
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作者 Shu-LinLang Xiao—YanTao +5 位作者 Zhen-YangGuo QingTang HaoLi Cui.PingYin YingLi Guo—DongLiang 《Virologica Sinica》 SCIE CAS CSCD 2012年第3期194-203,共10页
In recent years (2007 to 2011), although the overall number of rabies cases in China has decreased, there is evidence of emerging or re-emerging cases in regions without previous rabies cases or with low incidence of ... In recent years (2007 to 2011), although the overall number of rabies cases in China has decreased, there is evidence of emerging or re-emerging cases in regions without previous rabies cases or with low incidence of rabies. To investigate the origin and the factors affecting the spread of rabies in China, specimens were collected from 2007 to 2011 from provinces with emerging and re-emerging cases and tested for the presence of the rabies virus. Positive specimens were combined with sequences from GenBank to perform comparisons of homology and functional sites, and to carry out phylogenetic analyses. Out of these regions, five provinces had 9 positive specimens from canine and cattle, and 34 canine or human specimens were obtained from previously high-incidence provinces. Complete sequences of G gene were obtained for these samples. Homology of the sequences of these 43 specimens was 87%-100% at the nucleotide level and 93.7% -100% at the amino acid level. These G gene sequences were combined with reference sequence from GenBank and used to construct a phylogenetic tree. The results showed that 43 specimens were all assigned to China clade I and clade II, with all specimens from emerging and re-emerging areas placed within clade I. Specimens isolated from Shanxi and Inner Mongolia in 2011 were distinct from previously-isolated local strains and had closer homology to strains from Hebei, Beijing and Tianjin whereas new isolates from Shanghai were tightly clustered with strains isolated in the 1990s. Finally, Shaanxi isolates were clustered with strains from adjacent Sichuan. Our results suggest that the rabies cases in emerging and re-emerging areas in China in the last 5 years are a consequence of the epidemic spreading from of neighboring provinces and regions experiencing a serious epidemic of rabies. 展开更多
关键词 Rabies virus G gene Genetic variation Molecular characteristics
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Viral Metagenomics Analysis of Planktonic Viruses in East Lake,Wuhan,China 被引量:8
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作者 Xingyi Ge Yongquan Wu +5 位作者 Meiniang Wang Jun Wang Lijun Wu Xinglou Yang Yuji Zhang Zhengli Shi 《Virologica Sinica》 SCIE CAS CSCD 2013年第5期280-290,共11页
East Lake(Lake Donghu),located in Wuhan,China,is a typical city freshwater lake that has been experiencing eutrophic conditions and algal blooming during recent years.Marine and fresh water are considered to contain a... East Lake(Lake Donghu),located in Wuhan,China,is a typical city freshwater lake that has been experiencing eutrophic conditions and algal blooming during recent years.Marine and fresh water are considered to contain a large number of viruses.However,little is known about their genetic diversity because of the limited techniques for culturing viruses.In this study,we conducted a viral metagenomic analysis using a high-throughput sequencing technique with samples collected from East Lake in Spring,Summer,Autumn,and Winter.The libraries from four samples each generated 234,669,71,837,12,820,and 34,236 contigs(>90 bp each),respectively.The genetic structure of the viral community revealed a high genetic diversity covering 23 viral families,with the majority of contigs homologous to DNA viruses,including members of Myoviridae,Podoviridae,Siphoviridae,Phycodnaviridae,and Microviridae,which infect bacteria or algae,and members of Circoviridae,which infect invertebrates and vertebrates.The highest viral genetic diversity occurred in samples collected in August,then December and June,and the least diversity in March.Most contigs have low-sequence identities with known viruses.PCR detection targeting the conserved sequences of genes(g20,psbA,psbD,and DNApol)of cyanophages further confirmed that there are novel cyanophages in the East Lake.Our viral metagenomic data provide the first preliminary understanding of the virome in one freshwater lake in China and would be helpful for novel virus discovery and the control of algal blooming in the future. 展开更多
关键词 Viral metagenomics East Lake Solexa high-throughput sequencing High-throughput sequencing (HTS) CYANOPHAGE
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Identification of a novel C-type lectin from the shrimp Litopenaeus vannamei and its role in defense against pathogens infection 被引量:1
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作者 罗展 张继泉 +3 位作者 李富花 张晓军 柳承璋 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期942-951,共10页
Acting as one of the pattern recognition receptors (PRRs), C-type lectin is believed to mediate pathogen recognition and plays an important role in the clearance of pathogens as part of the innate immune system. In ... Acting as one of the pattern recognition receptors (PRRs), C-type lectin is believed to mediate pathogen recognition and plays an important role in the clearance of pathogens as part of the innate immune system. In this work, a novel C-type lectin gene (named LvLecl) was cloned from the shrimp Litopenaeus vannamei, The ORF of LvLecl is 510 bp, encoding 169 amino acids. The deduced amino acid sequence contains a putative signal peptide of 19 amino acids at the N-terminal and a carbohydrate recognition domain (CRD) at the C-terminal. LvLecl was mainly expressed in the hepatopancreas. Real-time PCR analysis indicated that the level of LvLecl transcripts significantly changed in the hepatopancreas after the shrimp were artificially challenged with LPS, Micrococcus lysodeikticus and white spot syndrome virus (WSSV). RNAi-based silencing of LvLecl resulted in increases in mortality when the shrimp were challenged with WSSV, and the median lethal time was reduced compared with controls. Although there was no characteristic "EPN" (Glu-Pro-Ser) or "QPD" (Gin-Pro-Asp) motif, the recombinant LvLecl, expressed in Escherichia coli BL21 (DE3), could also agglutinate M. lysodeikticus and Vibrio anguillarum. The agglutinating activities were calcium-dependent and could be inhibited by D-mannose, D-glucose, D-galactose and N-Acetyl-D-mannose. These results suggest that LvLecl might be involved in the immune response against WSSV and bacterial infections and contribute to non-self recognition as a pattern recognition receptor in the innate immune system of the shrimp L. vannamei. 展开更多
关键词 Litopenaeus vannamei innate immune pattern recognition receptor C-type lectin RNAinterference (RNAi) recombinant expression
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Potential implications of Helicobacter pylori-related neutrophil-activating protein 被引量:5
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作者 Jannis Kountouras Christos Zavos +7 位作者 Georgia Deretzi Emmanuel Gavalas Dimitrios Chatzopoulos Panagiotis Katsinelos Elena Tsiaousi Stergios Gagalis Stergios A Polyzos Ioannis Venizelos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第5期489-490,共2页
Helicobacter pylori (H. pylori) virulence factors pro- mote the release of various chemoattractants/inflam- matory mediators, including mainly the neutrophil- attractant chemokine interleukin-8 and neutrophil- activ... Helicobacter pylori (H. pylori) virulence factors pro- mote the release of various chemoattractants/inflam- matory mediators, including mainly the neutrophil- attractant chemokine interleukin-8 and neutrophil- activating protein (NAP), involved in H. pylor/-induced gastric pathologies. Co-administration of Chios mastic gum (CMG), which inhibits H. pylor/NAP, with an H. pylori eradication regimen might add clinical benefits against H. pylori-related gastric pathologies, but pos- sibly not CMG as main therapy. Although H. pylori NAP and other H. pylori-related cytotoxins [i.e., vaculating cytotoxin (VacA)] appear to play a major role in gener- ating and maintaining the H. pylori-associated gastric inflammatory response and H. pylor/NAP is a promising vaccine candidate against H. pylori infection (H. pylori-1), concerns regarding its potential drawbacks, particularly neurogenic ones, due to possible cross- mimicry, should be considered. Possible cross-mimicry between H. p, vlor/ NAP and/or bacterial aquaporin (AQP) and neural tissues may be associated with the anti-AQP-4 antibody-related neural damage in multiple sclerosis (MS)/neuromyelitis optica patients. Moreover, the sequence homology found between H. pylori VacA and human Na+/K+-ATPase A subunit suggests that antibodies to VacA involve ion channels in abaxonal Schwann cell plasmalemma resulting in demyelination in some patients. A series of factors have been im- plicated in inducing blood-brain barrier (BBB) disrup- tion, including inflammatory mediators (e.g., cytokines and chemokines induced by H. pylor/-I) and oxidative stress. BBB disruption permits access of AQP4-specific antibodies and T lymphocytes to the central nervous system, thereby playing a major role in multiple sclero- sis pathogenesis. Relative studies show a strong asso- ciation between H. pylori-I and MS. H. pylor/-I induces humoral and cellular immune responses that, owing to the sharing of homologous epitopes (molecular mim- icry), cross-react with components of nerves, thereby contributing and perpetuating neural tissue damage. Finally, H. pylori NAP also plays a possible pathoge- netic role in both gastric and colon oncogenesis. 展开更多
关键词 Helicobacter pylor/ Neutrophil-activatingprotein Chios mastic gum Cross-mimicry Multiplesclerosis DEMYELINATION Gastric carcinogenesis
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A de novo originated gene depresses budding yeast mating pathway and is repressed by the protein encoded by its antisense strand 被引量:7
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作者 Dan Li Yang Dong +3 位作者 Yu Jiang Huifeng Jiang Jing Cai Wen Wang 《Cell Research》 SCIE CAS CSCD 2010年第4期408-420,共13页
Recent transcription profiling studies have revealed an unexpectedly large proportion of antisense transcripts in eukaryotic genomes. These antisense genes seem to regulate gene expression by interacting with sense ge... Recent transcription profiling studies have revealed an unexpectedly large proportion of antisense transcripts in eukaryotic genomes. These antisense genes seem to regulate gene expression by interacting with sense genes. Previ- ous studies have focused on the non-coding antisense genes, but the possible regulatory role of the antisense protein is poorly understood. In this study, we found that a protein encoded by the antisense gene ADF1 acts as a transcription suppressor, regulating the expression of sense gene MDF1 in Saccharomyces cerevisiae. Based on the evolutionary, ge- netic, cytological and biochemical evidence, we show that the protein-coding sense gene MDF1 most likely originated de novo from a previously non-coding sequence and can significantly suppress the mating efficiency of baker's yeast in rich medium by binding MATa2 and thus promote vegetative growth. These results shed new light on several im- portant issues, including a new sense-antisense interaction mechanism, the de novo origination of a functional gene, and the regulation of yeast mating pathway. 展开更多
关键词 de novo sense-antisense interaction mating pathway Saccharomyces cerevisiae
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Characterization of the Xenopus homolog of animmediate early gene associated with cell activation: sequence analysis and regulation of its expression by thyroid hormone during amphibian metamorphosis
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作者 VIVIACTLIANG TIFFANYSEDGWICK 《Cell Research》 SCIE CAS CSCD 1997年第2期179-193,共15页
The complex transformation of a tadpole to a frogduring amphibian development is under the control of thyroid hormone (T3). T3 is known to regulate gene transcription through its nuclear receptors. We have previouslyi... The complex transformation of a tadpole to a frogduring amphibian development is under the control of thyroid hormone (T3). T3 is known to regulate gene transcription through its nuclear receptors. We have previouslyisolated many genes which are up-regulated by T3 in theintestine of Xenopus laevis tadpoles. We have now cloneda full- length cDNA for one such gene (IU12). Sequenceanalysis shows that the IU12 cDNA encodes a plasmamembrane protein with 12 transmembrane domains andhomologous to a mammalian gene associated with cell activation and organ development. Similarly, we have foundthat IU12 is activated during intestinal remodeling whenboth cell death and proliferation take place. Furthermore,IU12 is an early T3-response gene and its expression in theintestine during T3-induced metamorphosis mimics thatduring normal development. These results argue for a roleof IU12 in the signal transduction pathways leading to intestinal metamorphosis. 展开更多
关键词 Thyroid hormone Xenopus laevis cell proliferation ORGANOGENESIS transcription factor
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