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81.
Regulation of hepatitis B virus replication by the phosphatidylinositol 3-kinase-akt signal transduction pathway 总被引:3,自引:1,他引:3 下载免费PDF全文
Guo H Zhou T Jiang D Cuconati A Xiao GH Block TM Guo JT 《Journal of virology》2007,81(18):10072-10080
82.
An Appropriate Cutoff Value for Determining the Colonization of Helicobacter pylori by the Pyrosequencing Method: Comparison with Conventional Methods 下载免费PDF全文
83.
Se Ryun Kwon Yue Jai Kang Dong Jin Lee Eun Hye Lee Yoon Kwon Nam Sung Koo Kim Ki Hong Kim 《Molecular biotechnology》2009,42(2):154-159
Vibrio anguillarum ghosts (VAG) were generated, for the first time, using a conjugation vector containing a ghost bacteria inducing cassette,
pRK-λPR-cI-Elysis, in which the expression of PhiX174 lysis gene E was controlled by the P
R
/cI regulatory system of lambda phage. By scanning electron microscopy, holes ranging 80–200 nm in diameter were observed in
the VAG. To avoid the presence of bacterial genomic DNA and an antibiotic resistance gene in the final VAG product, we constructed
a new dual vector, pRK-λPR-cI-E-SNA, containing the E-mediated lysis cassette and the staphylococcal nuclease A (SNA)-mediated DNA degradation cassette, and generated safety-enhanced VAG for use as a fish vaccine. 相似文献
84.
85.
Mingjun Liao Feihai Yu Minghua Song Shumin Zhang Jinzheng Zhang Ming Dong 《Acta Oecologica》2003,24(5-6):231-239
Clonal fragments of the stoloniferous herb Glechoma longituba were subjected to a complementary patchiness of light and soil nutrients including two spatially homogeneous treatments (SR–SR and IP–IP) and two spatially heterogeneous treatments (IP–SR and SR–IP). SR and IP indicate patches (shaded, rich) with low light intensity (shaded, S), high nutrient availability (rich, R) and patches (illuminated, poor) with high light intensity (illuminated, I) and low nutrient availability (poor, P), respectively. Plasticity of the species in root–shoot ratio, fitness-related traits (biomass, number of ramets and dry weight per ramet) and clonal morphological traits (length and specific length of stolon internodes, area and specific area of laminae, length and specific length of petioles) were experimentally examined. The aim is to understand adaptation of G. longituba to the environment with reciprocal patches of light and soil nutrients by plasticities both in root–shoot ratio and in (clonal) morphology. Our experiment revealed performance of the clonal fragments growing from patches with high light intensity and low soil nutrient availability into the adjacent opposite patches was increased in terms of the fitness-related characters. R/S ratio and clonal morphology were plastic. Meanwhile, the capture of light resource from the light-rich patches was enhanced while the capture of soil nutrients from either the nutrient-rich or the nutrient-poor patches was not. Analysis of cost and benefit disclosed positive effects of clonal integration on biomass production of ramets in the patches with low light intensity and high soil nutrient availability. These results suggest an existence of reciprocal translocation of assimilates and nutrients between the interconnected ramets. The reinforced performance of the clonal fragments seems to be related with specialization of clonal morphology in the species. 相似文献
86.
目的:了解不同试剂在应用实时荧光定量聚合酶链反应(FQ-PCR)以及巢式PCR方法在检测低拷贝数的HBV DNA量的差异与灵敏度.方法:用上海复星医学科技发展有限公司(A方法)检测出了68例HBV DNA结果为5.1× 101-1.0× 103拷贝数/毫升的低拷贝数标本.然后,三家不同公司的试剂(方法B、方法C、方法D)对这些样本进行复核.另外,巢式聚合酶链反应PCR法检测此68例标本.随访巢式PCR结果为阳性的10例低拷贝数HBV DNA的病人.结果:用四种方法(A、B、C、D)检测的68个样本的HBV DNA拷贝数结果如下:无拷贝(0,9,12,4);101-102 (21,17,18,22);102-103(47,36,28,35),大于103(0,6,10,7).同时,用巢式聚合酶链反应检测此68例标本,有55例检测为阳性,有13为阴性结果.巢式PCR结果为阳性的10例低拷贝数HBV DNA含量的病人,随访发现此10病人有8例均在1~3月后出现HBV DNA的反跳,并伴肝功能的不正常,其HBV DNA的含量均在104拷贝数/毫升以上.结论:目前所用的实时荧光定量聚合酶链反应(FQ-PCR)的方法和试剂对低拷贝数HBV DNA存在不稳定性和不确定性.巢式PCR法对低拷贝数HBV DNA的检测灵敏度要远高于实时荧光定量PCR法.该研究提示测对抗病毒治疗过程中患者进行低拷贝数HBV DNA的检将提供有效的药物评价和预后信息. 相似文献
87.
目的探讨早孕猕猴给予大剂量RU486 3天后海马糖皮质激素受体(GR)的表达变化.方法 15只早孕猕猴随机分为空白对照组、赋形剂组和RU486组.空白对照组不予任何处理,赋形剂组和RU486组分别鼻饲赋形剂和RU486 3天.应用单克隆抗体链菌素亲生物蛋白过氧化酶(SP)免疫组织化学方法观察海马GR的表达情况,并用电子计算机图象分析技术进行处理.结果 RU486组猕猴妊娠终止,该组的海马GR表达显著下降,与对照组的差异有显著性.空白对照组和赋形剂组猕猴妊娠没有终止,其海马GR表达无差异.结论 RU486可使早孕猕猴海马的GR表达下降,推测这可能是该药终止妊娠的中枢作用机理之一. 相似文献
88.
To characterize protein phosphorylation in developing seed, a large-scale, mass spectrometry-based phosphoproteomic study was performed on whole seeds at five sequential stages of development in soybean (Glycine max), rapeseed (Brassica napus), and Arabidopsis (Arabidopsis thaliana). Phosphopeptides were enriched from 0.5 mg of total peptides using a combined strategy of immobilized metal affinity and metal oxide affinity chromatography. Enriched phosphopeptides were analyzed by Orbitrap tandem mass spectrometry and mass spectra mined against cognate genome or cDNA databases in both forward and randomized orientations, the latter to calculate false discovery rate. We identified a total of 2,001 phosphopeptides containing 1,026 unambiguous phosphorylation sites from 956 proteins, with an average false discovery rate of 0.78% for the entire study. The entire data set was uploaded into the Plant Protein Phosphorylation Database (www.p3db.org), including all meta-data and annotated spectra. The Plant Protein Phosphorylation Database is a portal for all plant phosphorylation data and allows for homology-based querying of experimentally determined phosphosites. Comparisons with other large-scale phosphoproteomic studies determined that 652 of the phosphoproteins are novel to this study. The unique proteins fall into several Gene Ontology categories, some of which are overrepresented in our study as well as other large-scale phosphoproteomic studies, including metabolic process and RNA binding; other categories are only overrepresented in our study, like embryonic development. This investigation shows the importance of analyzing multiple plants and plant organs to comprehensively map the complete plant phosphoproteome. 相似文献
89.
Artesunate exerts an anti‐immunosuppressive effect on cervical cancer by inhibiting PGE2 production and Foxp3 expression 下载免费PDF全文
90.