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Migration and population genetics of the grain aphid Macrosiphum miscanti (Takahashi) in relation to the geographic distance and gene flow

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Progress in Natural Science:Materials International 2005年第11期15卷 1000-1004页

作者： GUO Wei, SHEN Zuorui, LI Zhihong and GAO Lingwang (college of agronomy and Biotechnology, china Agricultural University, Beijing 100094, china) college of agronomy and Biotechnology China Agricultural University Beijing 100094 China

The population genetics of the grain aphid Macrosiphum miscanti (Takahashi) is analyzed by microsatellite markers. Samples collected from 15 locations in china have been examined at 5 polymorphic microsatellite loci. Overall, genetic diversity displays a relation between the migration and gene flow in the grain aphid; a free and frequent gene flow is found in the eastern populations, and gene isolation occurs in the two western populations, especially Datong population and Guiyang population. The natural barriers may present an insurmountable obstacle preventing gene flow and aphid migration. However, a spatial genetic differentiation between populations is correlated with their geographical separation, indicating the geographic differentiation may play an important role in shaping the genetic structure of M. miscanti populations. In addition, most populations of grain aphids are out of Hardy-Weinberg equilibrium and there is het-erozygote deficit. Based on F statistics, the average genetic differentiation among different geographical populations is relatively low. It seems that the long distance migration of the grain aphid may enhance gene flow and decrease genetic differentiation among different populations .

关键词： Macrosiphum miscanti microsatellite gene flow migration.

Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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Science china(Technological Sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2 & XU WeiSheng 2 1 college of Hydraulic and Environmental Engineering,china Three Gorges University,Yichang 443002,china 2 college of Hydropower Engineering,Xi’an University of Technology,Xi’an 710048,china college of Hydraulic and Environmental Engineering China Three Gorges University Yichang China college of Hydropower Engineering Xi’an University of Technology Xi’an China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

维普期刊数据库

BAF Complex Is Closely Related to and Interacts with NF1/CTF and RNA Polymerase Ⅱ in Gene Transcriptional Activation

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Acta Biochimica et Biophysica Sinica 2005年第7期37卷 440-446页

作者： Li-Hui ZHAO~(1,2) Xue-Qing BA~1 Xiao-Guang WANG~3 Xiao-Juan ZHU~1 Li WANG~1 Xian-Lu ZENG~1 1 Institute of Genetics and Cytology,Northeast Normal University,Changchun 130024,china 2 college of agronomy,Jilin Agricultural University,Changchun 130118,china 3 Department of Biology,Changchun Normal college,Changchun 130032,china Institute of Genetics and Cytology Northeast Normal UniversityChangchun 130024 China college of agronomy Jilin Agricultural UniversityChangchun 130118 China Department of Biology Changchun Normal CollegeChangchun 130032 China

Brg-or hBrm-associated factor (BAF) complexes,a chromatin-remodeling complex family ofmammalian cells,facilitate transcriptional activity by remodeling nucleosome ***1 is the coresubunit of Brg-associated factor *** the present study,we investigated the spatial relationshipbetween Brg1 and nuclear factor 1 (NF1/CTF) and RNA polymerase Ⅱ (RNAP Ⅱ) upon gene transcriptionalactivation in vivo by employing immuno-gold *** data showed that Brg1 was closely co-localizedwith NF1/CTF and RNAP Ⅱ in HeLa ***,the co-immunoprecipitation assay further revealedthat Brg1 can be isolated together with NF1/CTF and RNAP Ⅱ in the ConA-stimulated,but not the resting,T *** combined results suggested that BAF complexes can interact with NF1/CTF and RNAPⅡ,and this interaction is closely dependent on the activation of gene transcription.

关键词： BAF complex NF1/CTF RNAP Ⅱ gene transcription

Expression of MaMAPK Gene in Seedlings of Malus *** Water Stress

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Acta Biochimica et Biophysica Sinica 2006年第4期38卷 281-286页

作者： Li-Xin PENG~(1,2) Ling-Kun GU~2 Cheng-Chao ZHENG~2 De-Quan LI~2* Huai-Rui SHU~2 1 Department of Horticulture,Tianjin Agricuhural college,Tianjin 300384,china 2 college of Life Science,Shandong Agricultural University,Tai'an 271018,china Department of Horticulture Tianjin Agricultural CollegeTianjin 300384 China college of Life Science Shandong Agricultural UniversityTai'an 271018 China

Seedlings of three species of Malus were used to study the expression of mitogen-activatedprotein kinase (MAPK) in response to water stress:Malus hupehensis,a drought-sensitive species;Malussieversii,a drought-tolerant species;and Malus micromalus,a middle *** showed that MalusMAPK (MaMAPK,GenBank accession ***435805) was expressed in both roots and leaves of seedlingsof the three Malus species treated with 20% polyethylene glycol for different time *** levelspeaked at 1.5 h after treatment with polyethylene glycol,then decreased to their lowest *** kinaseassays indicated that the dynamic changes of MAPK activity were very similar to those of the relativeexpression of MaMAPK ***,the peak of the former occurred slightly behind the *** wasnoticed that,although the kinase activity decreased after the peak,it was still higher than that of the controlduring the whole time *** results suggested that MaMAPK was regulated not only by water stressat the transcription level,but also by phosphorylation and dephosphorylation at the protein *** addition,of these three apple species,the highest MAPK activity and MaMAPK expression level was found in ***,followed by *** and ***,suggesting that MAPK might be correlated withdrought tolerance in these three *** different expression levels might be one of the molecularmechanisms of the different drought tolerances in Malus.

关键词： expression characteristics Malus L. MaMAPK gene water stress

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 college of Life Science,Capital Normal University,Beijing 100037,china 2 college of Applied Sciences and Humanities,Beijing Union University,Beijing 100083,china college of Life Science Capital Normal UniversityBeijing 100037 China college of Applied Sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

Protective Effects of Vitamin E against Oxidative Damage Induced by Aβ(1-40)Cu(Ⅱ)Complexes

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 123-130页

作者： Xueling DAI~1 Yaxuan SUN~2 and Zhaofeng JIANG~2 ~1college of Life Science,Capital Normal University,Bejing 100037,china ~2college of Applied Sciences Humanities of Beijing Union University,Beijing 100083,china college of Life Science Capital Normal UniversityBeijing 100037 China college of Applied Sciences and Humanities of Beijing Union UniversityBeijing 100083 China

β-amyloid peptide （Aβ） is considered to be responsible for the formation of senile plaques,which is the hallmark of Alzheimer's disease （AD）.Oxidative stress,manifested by protein oxidation andlipid peroxidation,among other alterations,is a characteristic of AD brain.A growing body of evidence hasbeen presented in support of Aβ1-40forming an oligomeric complex that binds copper at a CuZn superoxidedismutase-like binding site. Aβ1-40Cu（Ⅱ） complexes generate neurotoxic hydrogen peroxide （H2O2） from O2via Cue+ reduction,though the precise reaction mechanism is *** toxicity of Aβ1-40or the Aβ1-40Cu（Ⅱ）complexes to cultured primary cortical neurons was partially attenuated when （+）-α-tocopherol （vitamin E）as free radical antioxidant was added at a concentration of 100 μ*** data derived from lactate dehydro-genase （LDH） release and the formation of H2O2confirmed the results from the MTT *** findingsindicate that copper binding to Aβ1-40can give rise to greater production of H2O2, which leads to a break-down in the integrity of the plasma membrane and subsequent neuronal *** treated with vitaminE exhibited much slighter damage,suggesting that vitamin E plays a key role in protecting neuronal cellsfrom dysfunction or death.

关键词： Aβ1-40Cu(II)complex vitamin E neuronal oxidative damage H2O2 generation lactate dehydrogenase(LDH)release

Palynological characters of Glycyrrhiza,Glycyrrhizopsis,and Meristotropis(Leguminosae),with special reference to their taxonomic significance

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Journal of Systematics and Evolution 2010年第6期48卷 455-463页

作者： 1,2Lei MENG 2Xiang-Yun ZHU 1(college of Biological Sciences,china Agricultural University,Beijing 100094,china) 2(Institute of Botany,Chinese Academy of Sciences,Beijing 100093,china) (college of Biological Sciences China Agricultural University Beijing 100094 China) (Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

The pollen morphology of 11 species of the genus Glycyrrhiza *** one from each of the genera Glycyrrhizopsis Boiss.& *** Meristotropis Fisch.& *** investigated by scanning electron *** pollen morphology,the main differences between Glycyrrhizopsis and Glycyrrhiza are:Glycyrrhizopsis-pollen grains 36.63 × 40.42 μm in size,oblate spheroidal in shape;and Glycyrrhiza-pollen grains 24.47-33.18 × 23.82-31.83 μm in size,prolate spheroidal in *** and Glycyrrhiza should be recognized as two distinct genera based on palynological and morphological *** and Glycyrrhiza are similar in many important palynological and morphological characters,suggesting that the two should be *** Glycyrrhiza,two types of pollen grains,3-lobed-circular or subtriangular in polar view,are found in different species,in accordance with morphological differences in the two groups,shedding light on the classification and evolution of the genus.

关键词： exine sculpture morphological character pollen morphology taxonomic revision.

Satellite RNA-mediated Reduction of Cucumber Mosaic Virus Genomic RNAs Accumulation in Nicotiana tabacum

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Acta Biochimica et Biophysica Sinica 2007年第3期39卷 217-223页

作者： Qiansheng LIAO~(1,2) Liping ZHU~2 Zhiyou DU~2 Rong ZENG~(2,3) Junli FENG~2 Jishuang CHEN~(1,2*) 1 college of Life Sciences,Zhejiang University,Hangzhon 310029,china 2 Institute of Bioengineering,Zhejiang Sci-Tech University,Hangzhou 310018,china 3 college of Biological Safety Technology Hunan Agricultural University,Changsha 410128,china college of Life Sciences Zhejiang UniversityHangzhou 310029 China Institute of Bioengineering Zhejiang Sci-Tech UniversityHangzhou 310018 China college of Biological Safety Technology Hunan Agricultural UniversityChangsha 410128 China

Satellite RNAs(satRNAs)are molecular parasites that interfere with the pathogenesis of thehelper *** this study,the relative accumulation of cucumber mosaic virus(CMV)-Fny genomicRNAs with or without satRNAs were quantitatively analyzed by real-time *** results showed thatsatRs apparently attenuated the symptoms of CMV-Fny on Nicotiana tabacum by depressing the accumu-lation of CMV-Fny genomic RNAs,tested as open reading *** accumulation of CMV-Fny 1a,2a,2b,3a,and CP genes was much higher than that of CMV-Fny with satRs added(CMV-Fsat),at differentinoculation ***-FnyΔ2b,in which the complete 2b gene and 41 amino acids at the C-terminal of the2a gene were deleted,caused only a slight mosaic effect on *** seedlings,similar to that of CMV-Fsat,but the addition of satRs to CMV-FnyΔ2b showed further decrease in the accumulation of CMV-FnyΔ2b genomic *** results indicated that the attenuation of CMV,by adding satRs or deleting the2b gene,was due to the low accumulation of CMV genomic RNAs,and that satRNA-mediated reduction ofCMV genomic RNAs accumulation in *** was possibly related to the 2b gene.

关键词： cucumber mosaic virus satellite RNA deletion of 2b gene relative accumulation

Phylogeny of Ptychostomum (Bryaceae,Musci) inferred from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) and chloroplast rps4

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Journal of Systematics and Evolution 2009年第4期47卷 311-320页

作者： ~(1,2)Chen-Ying WANG ~1Jian-Cheng ZHAO~* 1(college of Life Science,Hebei Normal University,Shijiazhuang 050016,china) 2(Department of Life Science,Zhengzhou Teachers college,Zhengzhou 450044,china) (college of Life Science Hebei Normal University Shijiazhuang 050016 China) (Department of Life Science Zhengzhou Teachers College Zhengzhou 450044 China)

The phylogeny of Ptychostomum was first undertaken based on analysis of the internal transcribed spacer(ITS)region of the nuclear ribosomal(nr)DNA and by combining data from nrDNA ITS and chloroplast DNA rps4 *** parsimony,maximum likelihood,and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not *** funkii(Schw(a|¨)gr.)*** (≡Bryum funkii Schw(a|¨)gr.)is placed within a clade containing the type species of Bryum,*** Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular *** the basis of phylogenetic evidence,we agree with transferring *** Mü***.(≡***(Brid.)Turton≡Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mü***.,Bryum pallescens *** Schw(a|¨)gr.,and Bryum pallens *** Ptychostomum.

关键词： Bryum molecular phylogeny nuclear ribosomal DNA internal transcribed spacer sequences Ptychostomum rps4 sequences.