检索结果-南通市图书馆

小鼠肌肉生长抑制素基因短发夹RNA促进MyoD在C2.1.0}胞中的表达(英文)

在线全文

学校读者我要写书评

暂无评论

生物化学与生物物理进展 2010年第4期37卷 451-459页

作者：娄颜坤罗娟代蓉李宁中国农业大学农业生物技术国家重点实验室北京100193 新疆石河子大学动物科学与技术学院石河子832000

肌肉生长抑制素(myostatin,MSTN)属于转化生长因子-β(transforming growth factor-β,TGF-β)超家族,主要功能为负向调节骨骼肌的生长.肌肉生长抑制素基因敲除小鼠肌肉出现显著增加,而将干涉该基因的短发夹RNA注射并电击转化入大鼠胫... 详细信息

肌肉生长抑制素(myostatin,MSTN)属于转化生长因子-β(transforming growth factor-β,TGF-β)超家族,主要功能为负向调节骨骼肌的生长.肌肉生长抑制素基因敲除小鼠肌肉出现显著增加,而将干涉该基因的短发夹RNA注射并电击转化入大鼠胫前肌则引起肌肉重量、肌纤维以及MHCⅡ表达的增加.通过与小鼠肌肉生长抑制素基因表达载体共转染HEK2.3细胞,筛选到两条能够高效抑制小鼠肌肉生长抑制素基因表达的小干涉RNA.构建了这两条小RNA的表达载体Mst-shRNA1.Mst-shRNA2.用其分别转染小鼠C2.1.0}肌细胞,并通过G41.药物筛选和流式细胞仪富集整合了短发夹RNA表达载体的阳性细胞.通过采用Real-time PCR和Western blot分析,检测到在分别整合了Mst-shRNA1.Mst-shRNA2.C2.1.0}胞中,内源性肌肉生长抑制素基因的mRNA水平分别下降了1..2.和35.5%,蛋白质表达则分别下降了2..3%和64.7%.同时,在这两组中MyoD的表达上升了2..4%和40.4%,证明通过RNA干涉实现的肌肉生长抑制素基因的抑制导致了下游MyoD基因表达的上调.这些结果表明内源性产生的肌肉生长抑制素基因小干涉RNA能够有效抑制该基因的表达.这种以RNA干涉技术为基础促进肌肉生长的方法为遗传育种提供了一种新技术,能够在对家畜经济性状的改良中发挥重要作用.

关键词：肌肉生长抑制素 RNA干涉小干涉RNA 短发夹RNA MyoD

Revealing the intrinsic mechanisms for accelerating nitrogen removal efficiency in the Anammox reactor by adding Fe(Ⅱ)at low temperature

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第8期35卷 341-348页

作者： linjing li Wenlai Xu Jianyong {2. Yaping Zhong Chuyue Zhang Jiane Zuo Zhicheng Pan state {1. {2. of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China state {1. Joint {2. of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China National Postdoctoral Research Station Haitian Water GroupChengdu 610213China National Enterprise Technology Center Haitian Water GroupChengdu 610213China Water Safety and Water Pollution Control Engineering Technology Research Center in Sichuan Province Chengdu 610213China laboratory of Municipal Wastewater Treatment Technology in Sichuan Province Chengdu 610213China Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolShenzhen 518055China

Fe(Ⅱ)is an essential trace element for anaerobic ammonium oxidation bacteria(AAOB)metabolism,and can improve the nitrogen removal efficiency of anaerobic ammonia oxidation(Anammox).Here we oper-ated two identical expanded granular sludge bed(EGSB)reactors at low temperature(1.±3℃)for 1.4 *** 1.R_(1.)received additional Fe(Ⅱ)(0.1.1.mmol/L)during the late startup phase,while reactor 0(R_(0))served as the control and did not receive extra Fe(Ⅱ).Nitrogen removal in R_(1.became stable at 55 d of operation,ten days earlier than R_(0).The nitrogen removal rate(NRR)of R_(1. was 1.64 kg N m^(−3)d^(−1.and its TN removal rate was as high as 89%,while R_(0)only reached 75%.The addition of Fe(Ⅱ)was fur-ther beneficial to aggregation and stability of the granular sludge,and the used sludge of both reactors showed enrichment for AAOB populations compared to the inoculum,for instance,increased abundance of Candidatus-Kuenenia and in particular of Candidatus-Brocadia(from 0.1.%to 1..1.%in R_(0)and 7.79%in R_(1.).Diverse microbial species and complex microbial network structure in R_(1.compared to R_(0)promoted the coupled denitrogenation by Anammox,dissimilatory nitrate reduction to ammonium(DNRA),nitrate-dependent Fe oxidation(NDFO),and ferric ammonium oxidation(Feammox).In addition,the microbial community in R_(1.was more resistant to short-term low temperature({1.7℃)starvation,illustrating a further positive effect of adding Fe(Ⅱ)during the startup phase of an Anammox reactor.

关键词： Ambient low temperature Anammox Fe(Ⅱ) Extracellular polymeric substances Microbial community Microbial network analysis

Research of blastocyte-like structure in chicken

在线全文

学校读者我要写书评

暂无评论

Science china({1.fe Sciences) 2005年第5期48卷 481-486页

作者： li Jia1, PAN Qiuzhen1, li Junying1, HAN Hongbing1, SUN Shufeng1, YANG Jun1, XU Shuguang, TIAN liang, liAN Zhengxing1,2. YANG ning1,2.& li ning2.3 1. College of Animal Science and Technology,{2., Beijing 100094, china 2. laboratory of Animal Genetics and Breeding, Ministry of Agriculture, Beijing 100094, china 3. state {12. laboratory of agrobiotechnology, Beijing 100094, china 1. College of Animal Science and Technology China Agricultural University 100094 Beijing China 2. {1. of Animal Genetics and Breeding Ministry of Agriculture 100094 Beijing China 3. state {1. {2. of {2. 100094 Beijing China

The chicken embryo is a classic model used to investigate embryonic development, gene expression, and tissue differentiation, and is also an important research tool in studying the animal functional genomics. The whole blastoderms of fresh unincubated eggs from White Leg-horn chickens were collected with a paper ring, mechanically broken into small pieces and cul-tured in medium. Then the small pieces would develop into blastocyte-like structures (BLS), which could be facilitated by an addition of fetal bovine serum (FBS) to the primary culture and their diameter was nearly doubled from 12.to 2. h. The additional yolk had no positive effect on the development in the first 12.h but encouraged the BLSs attaching and inner cells differentiat-ing instead in 2. h. The inner cells of the BLS showing a high alkaline-phosphatase activity similar to those in mouse embryonic stem (ES) cells and also expressing a large amount of the specific stage embryonic antigen-1 (SSEA-1) on the surface, which was known to be the char-acteristic of non-differentiated mouse and avian ES cells, could finally differentiate into nerve-like cells, fibroblast cells and so on in the medium. Leukemia inhibitory factor (liF) facilitated the cells’ proliferation and prevented differentiation in the suspended culture of the BLSs. So we drew the conclusion that the BLS obtained from broken blastoderm can be used to amplify avian ES cells so as to initiate a new method of producing transgenic chickens.

关键词： BLS, blastocyst-like structure, embryonic stem cells, ES cells, chicken.

Aberrant histone H4 acetylation in dead somatic cell-cloned calves

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2008年第7期18卷 813-818页

作者： Lei Zhang a,b,*, Shaohua Wang a, Qiang li a, Xiangdong Ding c, Yunping Dai a, {1. li a,* a state key {2. for agrobiotechnology, china agricultural university, Beijing 1.0094, china b Beijing Gene & Protein Biotechnology Co. LTD, Beijing 1.0094, china c College of Animal Science and Technology, china agricultural university, Beijing 1.0094, china state {1. {2. for {2. China Agricultural University Beijing 100094 China Beijing Gene & Protein Biotechnology Co. LTD Beijing 100094 China College of Animal Science and Technology China Agricultural University Beijing 100094 China

In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 1. development-related genes and expression levels of 1. genes in lungs of three normal control calves and nine aber- rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 1. genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p 1.genes showed lowered levels of both histone H4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

关键词： Somatic cell-cloned calves Histone H4 acetylation Gene expression Lungs

Expression of Basic Fibroblast Growth Factor Results in the Decrease of Myostatin mRNA in Murine C2.1.0}Myoblasts

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Biochimica et Biophysica Sinica 2006年第10期38卷 697-703页

作者： Hua-Zhong liU~(1,2. Qing li~1 Xing-Yuan YANG~1 lin liU~1 Lei liU~1 Xiao-Rong AN~1* Yong-Fu CHEN~1 1 state key laboratory for {2.,College of Biological Science,china agricultural university,Beijing 100094,china 2.Modern Biochemistry Center,Guangdong Ocean university,Zhanjiang 52.088,china state{1.{2.for{2. CollegeofBiologicalScienceChinaAgriculturalUniversityBeijing100094China ModernBiochemistryCenter GuangdongOceanUniversityZhanjiang524088China

during the development and regeneration of skeletal muscle,many growth factors,such asbasic fibroblast growth factor (bFGF,FGF-{1. and myostatin,have been shown to play regulating *** contributes to promote proliferation and to inhibit differentiation of skeletal muscle,whereas myostatinplays a series of contrasting *** order to elucidate whether the expression of bFGF has any relationshipwith the expression of myostatin in skeletal muscle cells,we constructed a eukaryotic expression vector forthe expression of exogenous bFGF in murine C{1.1.1.*** RT-PCR assays indicated thatwith the increase of the expression of exogenous bFGF gene,the expression of endogenous myostatin genewas suppressed at mRNA level and protein level.

关键词： basic fibroblast growth factor myostatin murine C2.1.0}myoblast real time RT-PCR

Revisiting the Mg isotopic systematics of siliciclastic components of sediments and sedimentary rocks:A new geochemical proxy of continental weathering in Earth's history

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth Sciences 2024年第2期67卷 620-633页

作者： Tianzheng HUANG Bing SHEN Kangjun HUANG Meng ning Chao {1. Jinzhuang XUE Yuan{1.n SUN Baoqi HUANG key {1. of Orogenic Belt and Crustal Evolution MOESchool of Earth and Space SciencesPeking UniversityBeijing100871China state {1. {2. of Continental Dynamics Shaanxi Key Laboratory of Early Life and EnvironmentsDepartment of GeologyNorthwest UniversityXi’an710069China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu610059China key {1. of Rhenium-Osmium Isotopic Geochemistry Chinese Academy of Geological SciencesBeijing100037China

The Mg isotopic compositions of siliciclastic components(δ^({1.)Mg_(sili))of sediments and sedimentary rocks have been commonly used to constrain the intensity of continental weathering,based on observations of,(1.an ... 详细信息

The Mg isotopic compositions of siliciclastic components(δ^(2.)Mg_(sili))of sediments and sedimentary rocks have been commonly used to constrain the intensity of continental weathering,based on observations of,(1)an upward enrichment of2.Mg in modern weathering profiles,(2.preferential uptake of2.Mg in soil clays,and(3)general positive correlations between weathering intensities andδ^(2.)Mg_(sili)***,not all weathering profiles display an upward increase ofδ^(2.)Mg_(sili),and not all soil clays enrich in2.Mg,complicating the interpretations ofδ^(2.)Mg_(sili)data of sediments and sedimentary *** further explore the controls ofδ^(2.)Mg_(sili)of sediments and sedimentary rocks,here we measuredδ^(2.)Mg_(sili),mineralogical compositions and major element compositions of deep sea sediments from South china Sea(SCS)and carbonate rock samples from two late Paleozoic sections in South *** samples show decreasing trends of both normalized Mg concentration(Mgnorm)andδ^(2.)Mg_(sili)values with the increase of weathering intensity,while SCS sediments samples do not show any correlation between Mgnormorδ^(2.)Mg_(sili)values and weathering intensity.A three-stages weathering model is developed to explain the observed Mgnorm andδ^(2.)Mg_(sili)*** the new model,weathering can be divided into three stages,(1)the preliminary weathering stage characterized by dissolution of primary minerals and formation of secondary clay minerals in saprolite,(2.the transitional stage with massive vermiculite and chlorite formation on the bottom of soil,and(3)the advanced stage showing dissolution of vermiculite and chlorite in the top of *** new model explains anδ^(2.)Mg_(sili)increase and Mgnormdecrease with an increase weathering intensity in preliminary weathering stage and decrease of Mgnormandδ^(2.)Mg_(sili)with increase weathering intensity in advanced weathering *** revised weathering model warrants the application of Mg isotope in the study of contin

关键词： Clay mineral Chemical weathering CIA Soil Weathering model

Invasive mechanism and control strategy of Ageratina adenophora (Sprengel)

在线全文

学校读者我要写书评

暂无评论

Science china({1.fe Sciences) 2010年第11期53卷 1291-1298页

作者： WAN FangHao1, liU WanXue1, GUO JianYing1, QIANG Sheng2. li BaoPing2. WANG JinJun3, YANG GuoQing1, NIU HongBang1, GUI FuRong1, HUANG WenKun1, JIANG Zhilin1 & WANG WenQi3 1state key laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of {2. Sciences, Beijing 100193, china 2.ollege of Plant Protection, Nanjing {2. university, Nanjing 2.0095, china 3key laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest university, Chongqing 400716, china 1. state {1. {2. for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100193 China2. College of Plant Protection Nanjing Agricultural University Nanjing 210095 China3. Key Laboratory of Entomology and Pest Control Engineering College of Plant Protection Southwest University Chongqing 400716 China

In order to ascertain the invasive mechanism and control strategy of the invasive Crofton weed, Ageratina adenophora, its ecological adaptability and population differentiation,the formation of single dominant population, displacement of native plants and sustainable management strategies were investigated. The present results helped to clarify and explain such issues as the adaptability post invasion,interaction and competition between inter-and intra-species and community resistance, thereby providing important references to researches on other invasive alien species.

关键词： Ageratina adenophora invasive mechanism genetic diversity ecological adaptation allelopathy feedback of soil biota competitive displacement

具有乳腺导管再生能力的小鼠乳腺原基细胞群黏附因子的表达特点

在线全文

学校读者我要写书评

暂无评论

生物化学与生物物理进展 2010年第5期37卷 490-495页

作者：宋嘉哲薛恺李松李宁中国农业大学生物学院农业生物技术国家重点实验室北京100193 北京济普霖生物技术有限公司北京100193

乳腺干细胞是研究器官形成、细胞增殖、分化、生存和凋亡等信号通路的理想模型,而近来的研究发现许多成体干细胞的特异性表面标记都与细胞黏附分子(celladhesion molecule,CAM)家族相关.因此,研究胚胎期乳腺干/祖细胞群的黏附分子基因... 详细信息

乳腺干细胞是研究器官形成、细胞增殖、分化、生存和凋亡等信号通路的理想模型,而近来的研究发现许多成体干细胞的特异性表面标记都与细胞黏附分子(celladhesion molecule,CAM)家族相关.因此,研究胚胎期乳腺干/祖细胞群的黏附分子基因表达特点,对于纯化和鉴定胚胎期乳腺干/祖细胞具有重要指导意义.用成年小鼠乳腺上皮干细胞的标记CD2.和CD49f来分选小鼠胚胎期1.天乳腺原基细胞群,发现CD2.+和CD49f+双阳性的乳腺原基细胞包含两个细胞群:CD2.hiCD49f+细胞群和CD2.medCD49f+细胞群.它们占乳腺原基总细胞的比例分别为1.%和47%.在随后的细胞培养实验和体内移植再生实验中发现,CD2.medCD49f+细胞群可以贴壁,而且具有再生乳腺导管的能力,相反,CD2.hiCD49f+细胞群既不能贴壁也不具有移植再生能力.这些结果表明,这两个细胞群分别代表不同的细胞类型,而CD2.medCD49f+细胞群有可能包含具有自我更新能力的乳腺原基干/祖细胞.挑选了可能与乳腺相关的1.个黏附分子,并对这两群细胞进行了定量PCR检测.结果表明,具有乳腺导管重建能力的CD2.medCD49f+细胞群的黏附分子基因表达明显区别于CD2.hiCD49f+细胞群,而且其中几个与成体干细胞相关的标记基因在CD2.medCD49f+细胞群中的表达显著高于CD2.hiCD49f+细胞群.

关键词：乳腺原基乳腺干细胞细胞黏附分子再生

Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3, li Xiaoying1,2.3, ZHANG Yong1,2.3, ZHAO Feng1,2.3, GU Xingfa1,3,4, ZHU li1,2.3, WANG Pengxin5 & MIN Xiangjun6 1. {2. key laboratory of Remote Sensing Science Institute of Remote Sensing Application, CAS, Bei- jing 100101,{2. 2. Graduate university of Chinese Academy of Sciences, Beijing 100039,{2. 3. The Center for National Spaceborne Demonstration, Beijing 100101,{2. 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. College of Information and Electrical Engineering, china agricultural university, Beijing 100083,{2. 6.{2. Center for Resource Satellite Data and Application, Beijing 100830,{2. 1. state {1. {2. of Remote Sensing Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The Center for National Spaceborne Demonstration 100101 Beijing China 3. Graduate {1. of Chinese Academy of Sciences 100039 Beijing China 4. Institut National de la Recherche Agronomique Climat Sol Environnent 84914 Avignon France 5. College of Information and Electrical Engineering China Agricultural University 100083 Beijing China 6. china Center for Resource Satel{1.te Data and App{1.cation 100830 Beijing China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.