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141.
PCR和生物素探针对HFRSV的检测和分型的探讨   总被引:2,自引:0,他引:2  
分析比较肾综合征出血热病毒(HFRSV)76/118株和R_(22)株的核苷酸序列,根据引物设计原则及检测分型的目的,设计并合成了3对引物。1对引物取于两毒株间的高同源区段,作为共同引物和外引物;另两对引物取于两毒株间的低同源区段,分别作为野鼠型引物、家鼠型引物和内引物。建立了DNA聚合酶链反应(PCR)和NestPCR方法,并用NcstPCR合成了两种型特异的生物素探针。PCR检测76/118、A_9、陈、R_2、R_225个毒株,用外引物时均扩增出1条约300bp的条带;用内引物的野鼠型引物时,除R_(22)株之外,其余4株均扩增出1条约70bp的条带。斑点杂交试验证实了PCR检测分型的准确性。NestPCR和生物素探针斑点杂交试验可以测出1-10bg的目的cDNA。  相似文献   
142.
本文论述了植物雄性不育的类型、原因、诱导和应用,总结了国内外在这方面的研究成果。重点对植物雄性不育的类型给以分析,从而丰富了遗传多样性的内容,展示了雄性不育理论和应用研究的光明前景。  相似文献   
143.
记述采自内蒙古自治区大青山地区的狼蛛科Lycosidae豹蛛属Pardosa一新种:大青山豹蛛Pardosa daqing shanica sp.nov.  相似文献   
144.
低盐浓度(0.2%NaCl)对红萍生长有促进作用,处理组形态比对照厚而大朵,根系较长,且健壮,含水量与对照相似,但高浓度使萍体含水量明显减少。萍体NaCl积累量随着培养液中盐浓度的增加而增加。生产指标测定表明,在低盐浓度下生长的红萍,叶绿素含量、固氮酶活性和全氮含量明显增加,可溶性糖含量则最低。低盐浓度促进红萍生长的原因可以归结为光合作用和固氮能力提高的结果。  相似文献   
145.
川西峨眉晚白垩世夹关期河流沉积中的痕迹化石群落*   总被引:9,自引:1,他引:8  
胡斌  吴贤涛 《古生物学报》1993,32(4):478-489
晚白垩世夹关组中的痕迹化石群落至少由12个痕迹属17个痕迹种组成,其中包括5个新痕迹种,即Cystichrtium cuwatitivum,Steinichnus laryus,Paradidymaulichnus emeiertsis,Monmorphichnus lineates和Rusophycus univalvis.这一化石群落主要是无脊椎动物的进食迹、觅食迹、爬迹、停息迹和居住迹,其中多数呈下浮痕和全浮痕保存,并形成于经常干旱的河流环境(大多出现在泛滥平原沉积中).该群落可识别出两个痕迹化石组合,即1) Scoyenia-Steinichnus-Rusophycus组合,它主要产自泛滥平原和漫滩环境;2)Skolithos-Arenicolites组合,它代表一种水道砂坝或曲流砂坝环境.  相似文献   
146.
Rotifers were cultured with five different organic and inorganic fertilizers in nursery ponds. Of the fertilizers used, mustard oil cake gave significantly (p < 0.01) higher production of rotifers than that of mohua oil cake followed by cow-dung, wheat bran, mixture of NPK and control. The higher production of rotifers was directly related with the higher doses of fertilizers. Among the rotifer species identified, the abundance of Brachionus caudatus and B. forficula were significantly (p < 0.01) higher than others. Available N, available P, exchangeable K and exchangeable Ca and exchangeable Mg were generally higher in ponds where organic fertilizers were used. Proximate composition of rotifers varied depending on the kinds of fertilizers. The multiple correlations of physico-chemical properties were highly significant (p < 0.01) with the growth and production of B. caudatus (R = 0.995), B. forficula (R = 0.932), Trichocerca capucina (R = 0.917), B. patulus (R = 0.901) and B. angularis (R = 0.892) and simply significant (p < 0.05) in the case of Keratella tropica (R = 0.880), Hexarthra intermadia (R = 0.875), B. calyciflorus (R = 0.864) and Filinia spp. (R = 0.856) contributing 91.20%, 86.86%, 84.09%, 81.18%, 79.57%, 77.44%, 76.56%, 74.65% and 73.27% of total effect of water properties on the growth of these species, respectively. The residual effect of nine different physico-chemical properties of water on the production of rotifers was 78.92% which indicates that these properties of water had only 21.08% influence on the production of rotifers.  相似文献   
147.
Dynamic Global Vegetation Models (DGVMs) provide a state-of-the-art process-based approach to study the complex interplay between vegetation and its physical environment. For example, they help to predict how terrestrial plants interact with climate, soils, disturbance and competition for resources. We argue that there is untapped potential for the use of DGVMs in ecological and ecophysiological research. One fundamental barrier to realize this potential is that many researchers with relevant expertize (ecology, plant physiology, soil science, etc.) lack access to the technical resources or awareness of the research potential of DGVMs. Here we present the Land Sites Platform (LSP): new software that facilitates single-site simulations with the Functionally Assembled Terrestrial Ecosystem Simulator, an advanced DGVM coupled with the Community Land Model. The LSP includes a Graphical User Interface and an Application Programming Interface, which improve the user experience and lower the technical thresholds for installing these model architectures and setting up model experiments. The software is distributed via version-controlled containers; researchers and students can run simulations directly on their personal computers or servers, with relatively low hardware requirements, and on different operating systems. Version 1.0 of the LSP supports site-level simulations. We provide input data for 20 established geo-ecological observation sites in Norway and workflows to add generic sites from public global datasets. The LSP makes standard model experiments with default data easily achievable (e.g., for educational or introductory purposes) while retaining flexibility for more advanced scientific uses. We further provide tools to visualize the model input and output, including simple examples to relate predictions to local observations. The LSP improves access to land surface and DGVM modelling as a building block of community cyberinfrastructure that may inspire new avenues for mechanistic ecosystem research across disciplines.  相似文献   
148.
用DNA聚合酶链反应检测单纯疱疹病毒特异性核酸,调查100名孕产妇生殖器官脂HSV感染和羊水受HSV污染的情况,结果表明:受感染的母体通过病毒护散途径及通过产道途径,污染羊水的机率分别为11.1%和54.5%;原发性HSV、继发性HSV垂直污染羊水机率分别为66.7%和29.4%;不同妊娠期和生育胎次对污染率无显著性影响。  相似文献   
149.
菊花离体快速繁殖的研究   总被引:1,自引:0,他引:1  
唐巍 《生物技术》1993,3(2):18-21
用MS基本培养基附加植物生长调节剂,进行了菊花离体快速繁殖试验。以幼叶为外植体在附加不同生长素的培寿基上诱导愈伤组织后进行分化培养。结果表明,2.OppmNAA上的愈伤组织诱导率最高,0.5ppmBA上的不定芽分化率最高。用不同浓度NAA与BA的组合进行分化试验,其方差分析结果说明0.1ppmNAA+0.5ppmBA是分化培养的最佳激素组合。无根苗在MS无激素培寿基上诱导生根,28天后移栽成活率达到85%。  相似文献   
150.

Background and aims

Although Helicobacter pylori is recognized as an extracellular infection bacterium, it can lead to an increase in the number of CD8+ T cells after infection. At present, the characteristics of H. pylori antigen-specific CD8+ T cells and the epitope response have not been elucidated. This study was focused on putative protective antigen UreB to detect specific CD8+ T-cell responses in vitro and screen for predominant response epitopes.

Methods

The PBMCs collected from H. pylori-infected individuals were stimulated by UreB peptide pools in vitro to identify the immunodominant CD8+ T-cell epitopes. Furthermore, their HLA restriction characteristics were detected accordingly by NGS. Finally, the relationship between immunodominant responses and appearance of gastric symptoms after H. pylori infection was conducted.

Results

UreB-specific CD8+ T-cell responses were detected in H. pylori-infected individuals. Three of UreB dominant epitopes (A-2 (UreB443–451: GVKPNMIIK), B-4 (UreB420–428: SEYVGSVEV), and C-1 (UreB5–13: SRKEYVSMY)) were firstly identified and mainly presented by HLA-A*1101, HLA-B*4001 and HLA-C*0702 alleles, respectively. C-1 responses were mostly occurred in H. pylori-infected subjects without gastric symptoms and may alleviate the degree of gastric inflammation.

Conclusions

The UreB dominant epitope-specific CD8+ T-cell response was closely related to the gastric symptoms after H. pylori infection, and the C-1 (UreB5-13) dominant peptides may be protective epitopes.  相似文献   
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