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11.
The characteristics of the particulate mouse centromere enriched fraction from isolated nuclei obtained in our laboratory were investigated by indirect immunofiuorescence, test of the activity of microtubule organizing center(MTOC), SDS-PAGE, and fluorescence in situ hybridization. Most of the particles of the fraction are complexes of DNA and kinetochore proteins and show MTOC activity. The DNA isolated from the fraction can hybridize with DNA in the regions of the primary constrictions of all chromosomes of ascites cells. The kinetochore proteins isolated from the fraction are mainly those with molecular weight of 55 KD and 59 KD. Results suggested that the fraction obtained is a centromere enriched nuclear fraction as indicated in our previous report.  相似文献   
12.
寡核苷酸探针(CAC)5/(GTG) 5指纹的非放射性标记和检测   总被引:1,自引:0,他引:1  
在DNA指纹分析中,通常采用的是同位素32P标记DNA分子探针,可检测到微微克(pg)靶序列。但32P半衰期很短(仅有14天),使用和运输均不方便,32P还放出硬射线,对实验者身体造成损害,需要一定的防护措施,并且容易污染环境。因此,科学家们研制出了...  相似文献   
13.
Seeding cells and scaffolds play pivotal roles in bone tissue engineering and regenerative medicine.Wharton’s jelly-derived mesenchymal stem cells(WJCs)from human umbilical cord represent attractive and promising seeding cells in tissue regeneration and engineering for treatment applications.This study was carried out to explore the biocompatibility of scaffolds to seeding cells in vitro.Rod-like nano-hydroxyapatite(RN-HA)and flake-like micro-hydroxyapatite(FM-HA)coatings were prepared on Mg-Zn-Ca alloy substrates using micro-arc oxidation and electrochemical deposition.WJCs were utilized to investigate the cellular biocompatibility of Mg-Zn-Ca alloys after different surface modifications by observing the cell adhesion,morphology,proliferation,and osteoblastic differentiation.The in vitro results indicated that the RN-HA coating group was more suitable for cell proliferation and cell osteoblastic differentiation than the FM-HA group,demonstrating better biocompatibility.Our results suggested that the RN-HA coating on Mg-Zn-Ca alloy substrates might be of great potential in bone tissue engineering.  相似文献   
14.
Phylogenetic methods have been widely used to detect the evolution of influenza viruses.However,previous phylogenetic studies of influenza viruses do not make full use of the genetic information at the protein level and therefore cannot distinguish the subtle differences among viral genes.Proteotyping is a new approach to study influenza virus evolution.It aimed at mining the potential genetic information of the viral gene at the protein level by visualizing unique amino acid signatures(proteotypes).Neuraminidase gene fragments of some H5N1 avian influenza viruses were used as an example to illustrate how the proteotyping method worked.Bayesian analysis confirmed that the NA gene tree was mainly divided into three lineages.The NA proteotype analysis further suggested there might be multiple proteotypes within these three lineages and even within single genotypes.At the same time,some proteotypes might even involve more than one genotype.In particular,it also discovered some amino acids of viruses of some genotypes might co-reassort.All these results proved this approach could provide additional information in contrast to results from standard phylogenetic tree analysis.  相似文献   
15.
The proteins encoded by the Herpesviridae β-gene play a critical role in the replication stage of the virus.In this paper,phylogenetic analyses provided evidence that some β-gene products,such as UL2 and UL23 from HSV1,have their homologous genes in its family,and also exist in prokaryotic organisms,indicating that these viruses appear to have been assembled over evolutionary time by numerous independent events of horizontal gene transfer.  相似文献   
16.
Effects of doubled CO2 and O3 concentration on Soybean were studied in open-top chambers (OTC). Under doubled CO2 concentration, grain yield and biomass increased, the SOD activity, vitamin C (Vc) and carotenoid (Car) content also increased; Superoxide (O2-) generating rate decreased, relative conductivity and malondialdehyde (MDA) content significantly declined. But under doubled O3 concentration, the SOD activity, Vc and Car contents declined, resulting in imbalance of activated-oxygen production, enhanced O2- generating rate and accelerated process of lipid peroxidation and increase in MDA content and ion leakage of leaves. The final result was decreased grain yield and plant biomass. Interactive effects of doubled CO2 and O3 concentrations on soybean were mostly counteractive. However, the beneficial effects of concentration-doubled CO2 are more than compensate the negative effects imposed by doubled O3, and the latter in its turn partly counteracted the positive effects of the former.  相似文献   
17.
The extra small virus (XSV) is a satellite virus associated with Macrobrachium rosenbergii nodavirus (MrNV) and its genome consists of two overlapping ORFs, CP17 and CP16. Here we demonstrate that CP16 is expressed from the second AUG of the CP17 gene and is not a proteinase cleavage result of CP17. We further expressed CP17 and several truncated CP17s (in which the N-or C-terminus or both was deleted), respectively, in Escherichia coli. Except for the recombinant plasmid CP17^AC10, all recombinant plasmids expressed soluble protein which assembled into virus-like particles (VLPs), suggesting that the C-terminus is important for VLP formation.  相似文献   
18.
2006年4~7月和2007年4~8月,在贵州贵定县境内采用定点观察法对领雀嘴鹎的繁殖行为进行了初步观察.结果 表明,领雀嘴鹎主要栖息于林缘次生林、河岸及斜坡灌丛林.繁殖期为4~8月,巢的结构为3层,营巢期6~8 d,窝卵数2~4枚,孵化期10~12 d,雏鸟留巢13 d.并测量了雏鸟的嘴蜂、跗跖、第5初级飞羽、尾长等的生长数据.  相似文献   
19.
Thecoatcolorisanimportantcharacteristicofapigbreed,andcanbeclassifiedintomanytypes.Thecolorvariationsareeitherduetothedistributionofmelanocytesintheskinortotheabilityofmelano-cytestoproducemelaningranules.Thesynthesisofmelaninoriginatedfromtheformationofneuralcrest-derivedcells,whichhavetwomigrationroutes[1,2].Themelanocytesaretheramificationswhiletheneuralcrest-derivedcellsmigrateviadorsalroute[3].Andtheyprovidethefactoryformelaninsynthesis.Al-thoughtherearemanykindsofpigmentsinvertebralanim…  相似文献   
20.
本文采用EBV(Epstein?Barr Virus)上清液转化B淋巴细胞,并加入环胞霉素A(Cyclosporine A)抑制T淋巴细胞,成功地对中国东北地区鄂温克族、鄂伦春族及达斡尔族的部分个体建立了永生细胞系,其中鄂温克族49株,鄂伦春族40株,达斡尔族51株,总计140株。永久保存我国特有民族的基因组,为分析其遗传学差异奠定了基础。 Abstract:The immortal lymphoblastoid cell lines were established by EBV transformation of B cells and addition of cyclosporin A to inhabit the activity of T cells.In the present study ,140 immortal cell lines of the Ewenki,the Oroqen and the Daur ethnic groups in the Northeast China were established .This is an important part of the research of human genome diversity for the exploration of the origin and progression of different ethnic groups ,and also provide enough research materials for further studies.  相似文献   
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