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表代数全体表基元乘积的不可约分解
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作者 梁晓莉 《西南师范大学学报(自然科学版)》 CAS CSCD 1996年第4期314-319,共6页
讨论一般非Abel单表代数(A,B),在什么条件下Irr(Ⅱb)=B成立,得到b∈B定理设(A,B)是一个实的非Abel单表代数,若以下条件之一成立(1)4≤|B|≤6.(2)|B|≥7时存在一对(bi,bj),bo... 讨论一般非Abel单表代数(A,B),在什么条件下Irr(Ⅱb)=B成立,得到b∈B定理设(A,B)是一个实的非Abel单表代数,若以下条件之一成立(1)4≤|B|≤6.(2)|B|≥7时存在一对(bi,bj),bo≠bj,使|Irr(bibj)|≥|B|-2.则Irr(Ⅱb)=B. 展开更多
关键词 表代数 表基 不可约分解 乘积
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心搏——健康的节律——世界卫生组织驻华代表基恩博士在1992年4月7日世界卫生日座谈会上的讲话
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作者 基恩 《中国健康教育》 1992年第5期19-19,共1页
心脏病发作、卒中和心血管病是世界上许多国家人口的主要死因。据估计,每年约有1200万人死于这些疾病。许多死于这些疾病的人,正处于成年早期,这些死亡对于他们社区的经济和社会生产影响很大。真正的悲剧还在于,约有半数的死亡尤其是年... 心脏病发作、卒中和心血管病是世界上许多国家人口的主要死因。据估计,每年约有1200万人死于这些疾病。许多死于这些疾病的人,正处于成年早期,这些死亡对于他们社区的经济和社会生产影响很大。真正的悲剧还在于,约有半数的死亡尤其是年青人的死亡是可以预防的。二、三十年前,心脏病发作和卒中被认为是发达国家的疾病。现在,在许多发展中国家里,尤其是像中国这样的国家里,期望寿命大幅度增加,许多传染病都得到了控制,心脏病发作和卒中明显地成为死亡和伤残主要原因。形成这种状况的原因有两个:一是与传染病有关,包括寄生虫和链球菌。 展开更多
关键词 世界卫生日 心搏 期望寿命 心脏病发作 成年早期 心血管病 表基 人的死亡 改善生活 高盐饮食
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Integrative analysis of bone-formation associated genes and immune cell infiltration in osteoporosis, and the prediction of active ingredients in targeted traditional Chinese medicine
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作者 WANG Kai DONG Ping GUO Hongzhang 《Digital Chinese Medicine》 CAS CSCD 2024年第2期160-170,共11页
Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of ... Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of targeted traditional Chinese medicine(TCM)herbs.Methods The Gene Expression Omnibus(GEO)and GeneCards databases were employed to conduct a comprehensive screening of genes and disease-associated loci pertinent to the pathogenesis of OP.The R package was utilized as the analytical tool for the identification of differentially expressed genes.Least absolute shrinkage and selection operator(LASSO)logis-tic regression analysis and support vector machine-recursive feature elimination(SVM-RFE)algorithm were employed in defining the genetic signature specific to OP.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses for the selected pivotal genes were conducted.The cell-type identification by estimating rela-tive subsets of RNA transcripts(CIBERSORT)algorithm was leveraged to examine the infiltra-tion patterns of immune cells;with Spearman’s rank correlation analysis utilized to assess the relationship between the expression levels of the genes and the presence of immune cells.Coremine Medical Database was used to screen out potential TCM herbs for the treatment of OP.Comparative Toxicogenomics Database(CTD)was employed for forecasting the TCM ac-tive ingredients targeting the key genes.AutoDock Vina 1.2.2 and GROMACS 2020 softwares were employed to conclude analysis results;facilitating the exploration of binding affinity and conformational dynamics between the TCM active ingredients and their biological targets.Results Ten genes were identified by intersecting the results from the GEO and GeneCards databases.Through the application of LASSO regression and SVM-RFE algorithm;four piv-otal genes were selected:coat protein(CP);kallikrein 3(KLK3);polymeraseγ(POLG);and transient receptor potential vanilloid 4(TRPV4).GO and KEGG pathway enrichment analy-ses revealed that these trait genes were predominantly engaged in the regulation of defense response activation;maintenance of cellular metal ion balance;and the production of chemokine ligand 5.These genes were notably associated with signaling pathways such as ferroptosis;porphyrin metabolism;and base excision repair.Immune infiltration analysis showed that key genes were highly correlated with immune cells.Macrophage M0;M1;M2;and resting dendritic cell were significantly different between groups;and there were signifi-cant differences between different groups(P<0.05).The interaction counts of resveratrol;curcumin;and quercetin with KLK3 were 7;3;and 2;respectively.It shows that the interac-tions of resveratrol;curcumin;and quercetin with KLK3 were substantial.Molecular docking and molecular dynamics simulations further confirmed the robust binding affinity of these bioactive compounds to the target genes.Conclusion Pivotal genes including CP;KLK3;POLG;and TRPV4;exhibited commendable significant prognostic value;and played a crucial role in the diagnostic assessment of OP.Resveratrol;curcumin;and quercetin;natural compounds found in TCM;showed promise in their potential to effectively modulate the bone-forming gene KLK3.This study provides a sci-entific basis for the interpretation of the pathogenesis of OP and the development of clinical drugs. 展开更多
关键词 OSTEOPOROSIS Bone formation Differentially expressed genes Biological information Traditional Chinese medicine(TCM) Active ingredients Molecular mechanism
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Tailoring the microenvironment of Ti sites in Ti-containing materials for synergizing with Au sites to boost propylene epoxidation
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作者 Shudong Shi Zhihua Zhang +3 位作者 Yundao Jing Wei Du Xuezhi Duan Xinggui Zhou 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期133-143,共11页
Au sites supported on Ti-containing materials(Au/Ti-containing catalyst)are currently considered as a promising catalyst for the propylene epoxidation owing to the synergistic effect that hydrogen peroxide species for... Au sites supported on Ti-containing materials(Au/Ti-containing catalyst)are currently considered as a promising catalyst for the propylene epoxidation owing to the synergistic effect that hydrogen peroxide species formed on Au sites diffuses to the Ti sites to form the Ti-hydroperoxo intermedi-ates and contributes to the formation of propylene oxide(PO).In principle,thermal treatment will significantly affect the chemical and physical structures of Ti-containing materials.Consequently,the synergy between tailored Ti sites with different surface properties and Au sites is highly expected to enhance the catalytic performance for the reaction.Herein,we systematically studied the intrinsic effects of different microenvironments around Ti sites on the PO adsorption/desorption and conversion,and then effectively improved the catalytic performance by tailoring the number of surface hydroxyl groups.The Ti^(Ⅵ) material with fewer hydroxyls stimulates a remarkable enhancement in PO selectivity and H_(2) efficiency compared to the Ti^(Ⅵ) material that possessed more hydroxyls,offering a 7-fold and 4-fold increase,respectively.As expected,the Ti^(Ⅵ+Ⅳ) and Ti^(Ⅳ) materials also exhibit a similar phenomenon to the Ti^(Ⅵ) materials through the same thermal treatment,which strongly supports that the Ti sites microenvironment is an important factor in suppressing PO con-version and enhancing catalytic performance.These insights could provide guidance for the rational preparation and optimization of Ti-containing materials synergizing with Au catalysts for propylene epoxidation. 展开更多
关键词 Propylene epoxidation MICROENVIRONMENT Ti-containing material Au-Ti synergy Hydroxyl group
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Transcriptome Sequencing for Sugar and Flavonoid Metabolism in Prunus persica‘Jinxiangyu’
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作者 CHEN Wei-feng WANG Chun-fa +2 位作者 HUANG Jia LI Du ZHANG Liang-bo 《Agricultural Science & Technology》 CAS 2024年第2期18-25,共8页
In this study,high performance liquid chromatography(HPLC)and RNA-seq transcriptome sequencing were used to study the changes in soluble sugar components and flavonoids in Prunus persica‘Jinxiangyu’at different deve... In this study,high performance liquid chromatography(HPLC)and RNA-seq transcriptome sequencing were used to study the changes in soluble sugar components and flavonoids in Prunus persica‘Jinxiangyu’at different developmental stages(20–90 d after flowering)and screen the key genes regulating the formation of soluble sugar and flavonoids in the fruits.The results showed that 60–85 d after flowering was the key stage of quality formation of Prunus persica‘Jinxiangyu’,and the content of soluble sugar,soluble solid,fructose,and sucrose in the fruit increased significantly during this period.The sugar content of ripe fruits was mainly fructose and sucrose.The content of kaempferol glycoside was low in the fruit.Quercetin glycoside content was higher in the young fruit stage and decreased with fruit maturity.There were no anthocyanin compounds in the fruit.The expression levels of genes involved in flavonoid metabolism(ANS,DFR,F3H,FLS,4CL1,etc.)were low in the fruit.A total of 181 differentially expressed genes were identified during fruit development to participate in five sugar metabolism pathways,among which the SDH gene had a higher expression level,which continuously rised in the later stage of fruit development.It mainly promoted the accumulation of fructose content in the later stage of fruit development.The expression levels of SPS1,SS,and SS1 genes were continuously up-regulated,which played a key role in sucrose regulation.The higher expression levels of SUS3 and INVA genes in the early stage of fruit development promoted the degradation of sucrose. 展开更多
关键词 Yellow peach Sugar metabolism Flavonoid compounds Differential gene expression
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Mechanism study on the influence of surface properties on the synthesis of dimethyl carbonate from CO_(2)and methanol over ceria catalysts
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作者 Lei Dong Shengjie Zhu +4 位作者 Yangyang Yuan Xiaomin Zhang Xiaowei Zhao Yanping Chen Lei Xu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期138-152,共15页
The direct synthesis of dimethyl carbonate(DMC)from CO_(2)and methanol has attracted much attention as an environmentally benign and alternative route for conventional routes.Herein,a series of cerium oxide catalysts ... The direct synthesis of dimethyl carbonate(DMC)from CO_(2)and methanol has attracted much attention as an environmentally benign and alternative route for conventional routes.Herein,a series of cerium oxide catalysts with various textural features and surface properties were prepared by the one-pot synthesis method for the direct DMC synthesis from CO_(2)and methanol,and the structure-performance relationship was investigated in detail.Characterization results revealed that both of surface acid-base properties and the oxygen vacancies contents decreased with the rising crystallinity at increasingly higher calcination temperature accompanied by an unexpectedly volcano-shaped trend of DMC yield observed on the catalysts.In situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)studies indicated that the adsorption rate of methanol is slower than that of CO_(2)and the methanol activation state largely influences the formation of key intermediate.Although the enhanced surface acidity-basicity and oxygen vacancies brought by low-temperature calcination could facilitate the activation of CO_(2),the presence of excess strongly basic sites on low-crystallinity sample was detrimental to DMC synthesis due to the preferred formation of unreactive mono/polydentate carbonates as well as the further impediment of methanol activation.Moreover,with the use of 2-cyanopyridine as a dehydration reagent,the DMC synthesis was found to be both influenced by the promotion from the rapid in situ removal of water and the inhibition from the competitive adsorption of hydration products on the same active sites. 展开更多
关键词 CeO_(2) Dimethyl carbonate Surface property Methanol activation 2-Cyanopyridine
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关于自正交的整表代数码
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作者 樊恽 刘宏伟 《数学进展》 CSCD 北大核心 2004年第4期467-470,共4页
整表代数是群代数的推广,它的理想是群代数码的推广.本文给出了整表代数的 单边理想是自正交理想的必要充分条件.
关键词 群代数 自正交理想 表基 整表代数码 编码理论
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Isolation and Identification of Submergence-induced Genes in Maize (Zea mays) Seedlings by Suppression Subtractive Hybridization 被引量:12
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作者 高鹏 王国英 +2 位作者 赵虎基 樊立 陶亚忠 《Acta Botanica Sinica》 CSCD 2003年第4期479-483,共5页
To investigate the expression profile of maize genes induced by submergence, a subtracted cDNA library of maize seedling roots was constructed using suppression subtractive hybridization (SSH). The cDNA of maize seedl... To investigate the expression profile of maize genes induced by submergence, a subtracted cDNA library of maize seedling roots was constructed using suppression subtractive hybridization (SSH). The cDNA of maize seedling roots treated with submergence (ST) was used as tester and what from untreated roots (UT) as driver. Products of the secondary PCR from the forward subtraction were cloned into T/A vector and transferred into Escherichia coli strain JM10B by electroporation. Four hundred and eight randomly chosen transformants carrying cDNA fragments were screened with PCR-Select Deferential Screening Kit. One hundred and eighty-four cDNA clones were identified as, submergence specifically induced or highly expressed. After sequencing and removing redundant cDNAs, we got 95 submergence-induced cDNA clones. Of the 95 cDNA clones, 68 contain the regions with 60%-90% identity to their homolog in GenBank, 21 are expected to be novel genes, only 6 correspond to the published maize sequences. 展开更多
关键词 MAIZE expression profile suppression subtractive hybridization (SSH) SUBMERGENCE
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Mechanisms of surface charge development of serpentine mineral 被引量:15
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作者 冯博 卢毅屏 +2 位作者 冯其明 丁鹏 罗娜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1123-1128,共6页
The electrokinetic behavior and surface dissolution of serpentine mineral were studied through Zeta potential measurements, dissolution experiments and X-ray photoelectron spectroscopy. The results show that serpentin... The electrokinetic behavior and surface dissolution of serpentine mineral were studied through Zeta potential measurements, dissolution experiments and X-ray photoelectron spectroscopy. The results show that serpentine has an iso-electric point (IEP) of 11.9, which is higher than that of other phyllosilicate minerals. Dissolution experiments show that the hydroxyl is easy to dissolve with respect to the magnesium cations in the magnesium oxide octahedral sheet. As a result of hydroxyl dissolution, the magnesium ions are left on serpentine surface, which is responsible for serpentine surface charge. The removal of magnesium ions from serpentine surface by acid leaching results in a decrease of serpentine IEP. Therefore, it has been clearly established that the surface charge developed at the serpentine/aqueous electrical interface is a function of the serpentine surface incongruent dissolution. 展开更多
关键词 SERPENTINE magnesium ions HYDROXYL surface charge incongruent dissolution
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Alterations of Root and Fiber in Transgenic Cotton Plants with Chimeric Ph/P-ipt Gene Expression 被引量:16
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作者 于晓红 朱勇清 +4 位作者 陈晓亚 许智宏 周宝良 陈松 沈新莲 《Acta Botanica Sinica》 CSCD 2000年第1期59-63,共5页
The seed_specific phaseolin promoter (Ph/P) was fused to an ipt gene, then was cloned to a plant expression vector containing a gus gene driven by a 35S promoter. Cotton (Gossypium hirsutum L.) plants were tr... The seed_specific phaseolin promoter (Ph/P) was fused to an ipt gene, then was cloned to a plant expression vector containing a gus gene driven by a 35S promoter. Cotton (Gossypium hirsutum L.) plants were transformed through pollen tube pathway methods. After seed germination, histochemical staining of the roots demonstrated that 32 GUS positive plants were obtained and three of which contained the chimeric Ph/P_ ipt transgene as confirmed by PCR analysis. An immunosorbent assay showed that two of the three transgenic cotton lines contained higher levels of zeatin equivalents in seeds than the control. Seedling development of these two transgenic lines differed from the control in a reduction of the shoot growth, showing a stunted phenotype as expected, but a surprisingly developed root system with a 3-4 fold fast_growing lateral roots. In addition, fibers (seed_hairs) of the two transgenic cotton lines were considerably shorter than those of the control. These results indicate that genetic engineering may be used to manipulate the development of cotton plants, particularly cotton fibers. 展开更多
关键词 CYTOKININ transgenic cotton ROOT FIBER
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Transformation of Pea Lectin Gene and Parasponia Haemoglobin Gene into Rice and Their Expressions 被引量:6
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作者 张静娴 王忆平 +4 位作者 沈世华 王逸群 高越峰 单雪琴 荆玉祥 《Acta Botanica Sinica》 CSCD 2001年第3期267-274,共8页
Lectin and leghemoglobin in legumes play the important roles, respectively, in recognition of host plants to their rhizobial bacteria, and lowering the oxygen partial pressure around bacteroids and protecting nitrogen... Lectin and leghemoglobin in legumes play the important roles, respectively, in recognition of host plants to their rhizobial bacteria, and lowering the oxygen partial pressure around bacteroids and protecting nitrogenase from oxygen in symbiotic nitrogen-fixing nodules. In order to extend the host range of the rhizobial bacteria and to make them fix nitrogen in non-legumes, pea lectin gene (pl) and Parasponia hemoglobin gene ( phl,) have been constructed into a plant expression vector (pCBHUL) and the vector pCBHUL was introduced into rice calli from immature young embryos by particle bombardment. After the calli were regenerated into plantlets on the resistant-selecting media containing hygromycin, they were identified by PCR and Southern blot hybridization. It was indicated that the pi and phb genes were integrated into nucleic genome of the transformed rice plants. GUS activity and the product of the pi gene were determined by GUS staining, Western blot and in situ hybridization at translational level. Eighteen out of 40 plants resistant to hygromycin were positively identified by PCR analysis with the rate of 45%. The pi gene was expressed in 3 out of 18 plants with 17% and 7.5% in 40 plants. The results may provide a clue for exploring whether Rhizobium leguminosarum by. viceae could extend its host range and make the transgenic rice plants have the possibility of being symbiotic, or associative to nitrogen fixation. 展开更多
关键词 Parasponia hemoglobin gene pea lectin gene particle bombardment transformation gene expression transgenic rice
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Cloning and Differential Expression of a 1-Aminocyclopropane-1-Carboxylate Synthase cDNA from Peach 被引量:2
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作者 金勇丰 朱立成 +1 位作者 张耀洲 张上隆 《Acta Botanica Sinica》 CSCD 2002年第10期1182-1187,共6页
The ACC synthase is the key enzyme in ethylene biosynthesis and fruit ripening. To study the mechanism of ACC synthase in peach Prunus persica (L.) Batsch) fruit ripening, we cloned a full_length cDNA of ACC synthase ... The ACC synthase is the key enzyme in ethylene biosynthesis and fruit ripening. To study the mechanism of ACC synthase in peach Prunus persica (L.) Batsch) fruit ripening, we cloned a full_length cDNA of ACC synthase pacs from peach using 5′/3′ RACE PCR. The nucleic acid sequence of pacs was 1 848 bp, containing 177 bp of 5′untranslated sequence, 1 449 bp of an open reading frame, and 219 bp of 3′untranslated sequence (excluding the stop codon TAA). The pacs open reading frame encoded a 483_amino acid polypeptide with a predicted size of 54 kD and a calculated PI of 6.43. The deduced protein from ACC synthase cDNA pacs had 65%, 70%, 75%, and 90% homology with the other deduced proteins from tomato (S19677), plum (AB031026), papaya (U68216) and apple (AB034993), which contained the active site of ACC synthase SLSKDMGFPGFR conserved among these plant ACC synthases. RNA_based PCR amplification combined with hybridization analysis with pacs and another ACC synthase cDNApacs12 (AF467782) cloned by us before as probes, indicated that expression patterns of both clones were very similar. mRNAs of both clones expressed in the alabastrum and petal, and were induced after ethylene treatment. Wounding and IAA treatments could induce ACC synthase expression of both clones in the leaves. However, the wounding treatment of leaves has induced more abundant pacs ACC synthase expression than that ofpacs12. Pacs mRNA expressed in both green mature and ripening fruit, whilepacs12mRNA was little or undetectable in green mature fruit, but apparent in ripening fruit. Both clone mRNAs accumulated more in leaves (following wounding and IAA treatments) and flowers than in fruits. 展开更多
关键词 Prunus persica ACC synthase CLONING differential expression
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Molecular Cloning, Escherichia coli Expression and Genomic Organization of Squalene Synthase Gene from Artemisia annua 被引量:5
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作者 刘彦 叶和春 +1 位作者 王红 李国凤 《Acta Botanica Sinica》 CSCD 2003年第5期608-613,共6页
A 1 539 by squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerise chain reaction (RT-PCR). The amino acid sequence of AaSQS is 70%, 77%, 44% and 3... A 1 539 by squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerise chain reaction (RT-PCR). The amino acid sequence of AaSQS is 70%, 77%, 44% and 39%a identical to that of squalene synthases from Arabidopsis thaliana, tobacco, human and yeast, respectively. The AaSQS genomic DNA has a complex organization containing 14 exons and 13 introns. Full-length or C-terminal truncated cDNA was subcloned into prokaryotic expression vector pET30a and the constructed plasmid was introduced to Escherichia coli strain BL21 (DE3) for induced overexpression. No squalene synthase protein with expected molecular mass was observed in E. cola containing the putative full-length squalene synthase cDNA, however, overexpression in E. coli was achieved by truncating 30 amino acids of hydrophobic region at the carboxy terminus. 展开更多
关键词 Artemisia annua squalene synthase Escherachia coli overexpression genomic organization CLONING
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The Relationship of Methyl Jasmonate Enhanced Powdery Mildew Resistance in Wheat and the Expressions of 9 Disease Resistance Related Genes 被引量:18
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作者 牛吉山 刘靖 +3 位作者 马文斌 李巧云 王正阳 贺德先 《Agricultural Science & Technology》 CAS 2011年第4期504-508,共5页
[Objective] This study was carried out to determine the induction effect of jasmonic acid(JA)on powdery mildew resistance in wheat,the activation effect on the expressions of plant disease resistance related genes,a... [Objective] This study was carried out to determine the induction effect of jasmonic acid(JA)on powdery mildew resistance in wheat,the activation effect on the expressions of plant disease resistance related genes,and to investigate the relationship between the induced resistance and the gene expression patterns.[Method] Three powdery mildew susceptible cultivars of "Chinese Spring","Pumai 9" and "Zhoumai 18" typically representing different phenotypes in the field were employed.The powdery mildew was assessed by detached leaf assay,and real time quantitative RT-PCR was used to determine the expression patterns of 9 disease resistance related genes of PR1(PR1.1),PR2(β,1-3 glucanase),PR3(chitinase),PR4(wheatwin1),PR5(thaumatin-like protein),PR9(TaPERO,peroxidase),PR10,TaGLP2a(germin-like)and Ta-JA2(jasmonate-induced protein)in leaf of the three cultivars.[Result] MeJA application enhanced the powdery mildew resistances of "Chinese Spring","Pumai 9" and "Zhoumai 18".The induced powdery mildew resistance could be detected from 12 h to 96 h after MeJA treatment,and the peak value was at 24 h.Though there were differences between the three cultivars,MeJA significantly effect on the expressions of the 8 disease resistance related genes except TaGLP2a,and the peak values were at 12 h,24 h or 48 h after treatments.The strongest activation of MeJA was on PR9 and PR1 that their expressions could reach more than 100 times of the untreated samples.MeJA strongly activated PR2、PR4、PR5、PR3、PR10 and Ta-JA2,their expression could reach 10 to 70 times,and there was almost no activation effect on TaGLP2a.The induced powdery mildew resistance positively correlated with the induced expressions of the 8 disease related genes.[Conclusion] The induced powdery mildew resistance positively correlated with the induced expressions of the disease related genes.Jasmonate signalling plays a role in defence against Blumeria graminis f.sp.tritici.and future manipulation of this pathway may improve powdery mildew resistance in wheat. 展开更多
关键词 WHEAT Powdery mildew Jasmonic acid(JA) Resistance Gene Expression
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Thermodynamics and kinetics of adsorption for heavy metal ions from aqueous solutions onto surface amino-bacterial cellulose 被引量:8
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作者 鲁敏 张月明 +2 位作者 关晓辉 徐小慧 高婷婷 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1912-1917,共6页
Amino-bacterial cellulose(amino-BC) was prepared by chemical modification of bacterial cellulose(BC).The adsorption characteristics and mechanism of amino-BC were studied.The results show that adsorption data can ... Amino-bacterial cellulose(amino-BC) was prepared by chemical modification of bacterial cellulose(BC).The adsorption characteristics and mechanism of amino-BC were studied.The results show that adsorption data can be fitted well by Langmuir equation and the pseudo-second order kinetics,indicating that the adsorption of amino-BC would obey monolayer molecule adsorption and the main action was chemisorption.Meanwhile,the adsorption process was studied by the Elovich equation and the intra-particle diffusion model,indicating that the absorption characteristics of metal ions on amino-BC is controlled by both film diffusion and particle diffusion.The increase of reaction temperature will accelerate the adsorbing rate because of endothermic reaction. 展开更多
关键词 surface amination bacterial cellulose adsorption thermodynamics adsorption kinetics
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Selection of Reference Genes in Transcription Analysis of Gene Expression of the Mandarin Fish, Siniperca chuasti 被引量:17
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作者 周瑞雪 蒙涛 +6 位作者 孟海波 陈敦学 宾石玉 成嘉 符贵红 褚武英 张建社 《Zoological Research》 CAS CSCD 北大核心 2010年第2期141-146,共6页
At present, transcription analysis of gene expression commonly uses housekeeping genes as control for normalization. In this study, the expression levels of three housekeeping genes including GAPDH, β-actin, and 18S ... At present, transcription analysis of gene expression commonly uses housekeeping genes as control for normalization. In this study, the expression levels of three housekeeping genes including GAPDH, β-actin, and 18S rRNA in six tissues and five developmental stages of the Mandarin fish Siniperca chuatsi were assayed with quantitative real-time PCR (qPCR). Differences in expression levels were analyzed using geNorm program. The results demonstrate that β-actin is the most stable gene at developmental stages and GAPDH is the most stable in different tissues. While 18S rRNA expression during development is differentially regulated, which indicates it is suitable as an internal control for gene expression normalization at the developmental level. Overall, the data suggest that the two most stable housekeeping genes are enough to accurately calibrate gene expression in S. chuatsi. The significance of this study provided convincing references and methodology for housekeeping gene selection and normalization in gene expression analysis with regular PCR or qPCR. 展开更多
关键词 Reference genes geNorm program Gene expression Real-time PCR
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Molecular Characterization of Cotton 14-3-3L Gene Preferentially Expressed During Fiber Elongation 被引量:3
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作者 石海燕 王秀兰 +4 位作者 李登弟 汤文开 汪虹 许文亮 李学宝 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第2期151-159,共9页
The 14-3-3 protein, highly conserved in all eukaryotic cells, is an important regulatory protein. It plays an important role in the growth, amplification, apoptosis, signal transduction, and other crucial life activit... The 14-3-3 protein, highly conserved in all eukaryotic cells, is an important regulatory protein. It plays an important role in the growth, amplification, apoptosis, signal transduction, and other crucial life activities of cells. A eDNA encoding a putative 14-3-3 protein was isolated from cotton fiber eDNA library. The eDNA, designated as Gh14-3-3L (Gossypium hirsutum 14-3-3-like), is 1,029 bp in length (including a 762 bp long open reading frame and 5'-/3'-untranslated regions) and deduced a protein with 253 amino acids. The GhI4-3-3L shares higher homology with the known plant 14-3-3 proteins, and possesses the basic structure of 14-3-3 proteins: one dimeric domain, one phosphoralated-serine rich motif, four CC domains, and one EF Hand motif. Northern blotting analysis showed that Gh14-3-3L was predominantly expressed during early fiber development, and reached to the peak of expression in 10 days post anthers (DPA) fiber cells, suggesting that the gene may be involved in regulating fiber elongation. The gene is also expressed at higher level in both ovule and petal, but displays lower or undeteetable level of activity in other tissues of cotton. 展开更多
关键词 COTTON 14-3-3 protein gene expression
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Cloning and Expression Pattern Analysis of Nitrogen- Starvation-induced Genes in Rice 被引量:3
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作者 陈青爽 易可可 +4 位作者 黄帼 王小兵 刘非燕 吴运荣 吴平 《Acta Botanica Sinica》 CSCD 2003年第8期974-980,共7页
To understand the regulation system of nitrogen X-starvation in higher plants, a cDNA library from N-starved rice (Oryza sativa L.) seedlings was constructed using rapid subtraction hybridization (RaSH) procedure. Thr... To understand the regulation system of nitrogen X-starvation in higher plants, a cDNA library from N-starved rice (Oryza sativa L.) seedlings was constructed using rapid subtraction hybridization (RaSH) procedure. Through reverse Northern analysis and Northern blotting, 18 unique known genes and two unique unknown genes were identified, which were up-regulated by N-starvation in rice. The known genes are involved in several metabolisms including carbon metabolism, secondary metabolite synthesis, ubiquitylation and protein degradation, phytohormone metabolism, signal transduction, growth regulator and transcription factors. Different induced expression patterns based on spatial and temporal express ions were found for these genes. The results indicate the cross-talks between N-starvation response and various metabolisms in plants. 展开更多
关键词 Oryza sativa RASH expression pattern nitrogen-starvation
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Transcriptional Regulation of 10 Mitochondrial Genes in Different Tissues of NCa CMS System in Brassica napus L. and Their Relationship with Sterility 被引量:3
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作者 危文亮 王汉中 刘贵华 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期72-80,共9页
Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revea... Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revealed that 9 out of the 10 mitochondrial genes, except for atp6, showed no difference in different tissues of the corresponding materials of NCα CMS system and that they might be constitutively expressed genes. Eight genes, such as orf139, orf222, atpl, cox1, cox2, cob, rm5S, and rm26S, showed no difference among the three tissues of all the materials detected. So the expression of these eight genes was not regulated by nuclear genes and was not tissue-specific. The transcripts of atp9 were identical among different tissues, but diverse among different materials, indicating that transcription of atp9 was neither controlled by nuclear gene nor tissue-specific. Gene atp6 displayed similar transcripts with the same size among different tissues of all the materials but differed in abundance among tissues of corresponding materials and its expression might be tissue-specific under regulation of nuclear gene. Moreover, three transcripts of orf222 were detected in the floral buds of NCa cms and fertile F1, but no transcript was detected in floral buds of the maintainer line.The transcription of orf139 was similar to that of orf222 but only two transcripts of 0.8 kb and 0.6 kb were produced. The atp9 probe detected a single transcript of 0.6 kb in NCa cms and in maintainer line and an additional transcript of 1.2 kb in fertile F1. The relationship of expression of orf222, orf139, and atp9 with NCa sterility was discussed. 展开更多
关键词 Brassica napus L. cytoplasmic male sterility (CMS) mitochondrial gene expression restorer gene transcriptional regulation
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Cloning and Analysis of CFL—A LFY_like Gene from Cucumber 被引量:9
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作者 刘复权 朱广廉 +2 位作者 罗达 吴相钰 许智宏 《Acta Botanica Sinica》 CSCD 1999年第8期813-819,共7页
LFY and LFY _like genes have been shown to control the initiation of floral meristems in higher plants. The homologous cDNA of LFY, CFL, were cloned from cucumber ( Cucumis sativus L.). Southern blot anal... LFY and LFY _like genes have been shown to control the initiation of floral meristems in higher plants. The homologous cDNA of LFY, CFL, were cloned from cucumber ( Cucumis sativus L.). Southern blot analysis showed it was a single copy gene in the cucumber genome. Northern blot analysis showed that it expressed in the floral buds and young leaves. The possible role of CFL in the floral and vegetative development of cucumber plant was discussed. 展开更多
关键词 LFY like genes Expression Cucumis sativus
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