简介:摘要:新兴词组“NP1在逃NP2”,从句法平面看,可以作主语、宾语、定语;从语义平面看,“在逃”义虚化,该词组其具有隐喻特点,色彩义由贬义变为偏向褒义和中性;从语用平面看,符合网络流行语求新立异的特点。
简介:AbstractLong-term and stable preservation of bacteriophages is of crucial importance. Although many efforts have been made in the past decades to explore the influence of external factors on bacteriophage preservation, there is still little understanding, and a systematic description is lacking. In this study, we explored the influence of different factors on the preservation of lytic bacteriophage VP3, one of the typing bacteriophages of Vibrio cholerae O1 biotype El Tor, and attempted to optimize its preservation. We examined external factors, including temperature, solution, and cryoprotectant, in stable cooling/freezing conditions or alternate cooling/freezing and thawing. We found that whether in Luria-Bertani (LB) medium or SM buffer, in terms of 20-week stable cooling or freezing, -20 °C was the most damaging while 4 °C, -80 °C, and -196 °C were protective. Thirteen cycles of alternate cooling/freezing and thawing caused a loss in the survival rates of bacteriophages. The addition of cryoprotectant, glycerol (30%, w/v) or dimethyl sulfoxide (DMSO, 10%, w/v) significantly improved the survival rates of bacteriophages preserved at -20 °C. However, at 4 °C, -80 °C, and -196 °C, the cryoprotectant effect was only slightly positive or even harmful. In summary, for bacteriophage VP3, the best preservation method is to directly preserve the bacteriophage stocks in LB medium at -80 °C or -196 °C instead of storing them in SM buffer or adding cryoprotectant. Our results provided insights into the external influencing factors on bacteriophage VP3 during preservation at low temperature and can be applied to the optimization of bacteriophage preservation in the future.
简介:摘要目的探索依托泊苷(VP-16)对人类免疫缺陷病毒(human immunodeficiency virus-1, HIV-1)潜伏感染的激活作用并研究其潜在的分子机制。方法将HIV-1潜伏感染细胞系J-Lat分为二甲基亚砜(DMSO)处理组、VP-16处理组及伏立诺他(SAHA)处理组,利用流式细胞技术检测细胞绿色荧光蛋白(green fluorescent protein, GFP)阳性比例,评估高浓度VP-16对HIV-1潜伏感染的激活效率;通过流式细胞技术检测VP-16在不同作用浓度及不同作用时间下对HIV-1潜伏感染的激活效果;通过流式细胞技术检测在VP-16作用下J-Lat细胞中CD25、CD69及白介素-6(interleukin-6, IL-6)的表达情况;运用双荧光素酶报告系统检测VP-16对HIV-1长末端重复序列(long terminal repeat, LTR)转录水平的影响;使用蛋白质印迹技术(western blot, WB)检测VP-16作用下蛋白沉默信息调节因子1(silent information regulator 1, SIRT1)及核因子κB(nuclear factor κB, NF-κB)乙酰化p65的表达水平;利用慢病毒介导的靶向SIRT1短发夹RNA(SIRT1 short-hairpin RNA, SIRT1-shRNA)敲低J-Lat细胞的SIRT1表达并检测相应的激活效果。结果流式细胞技术分析结果显示,VP-16能够特异性地激活HIV-1潜伏感染细胞系J-Lat,其激活效果存在浓度依赖和时间依赖;VP-16激活HIV-1潜伏感染的同时会一定程度上调J-Lat细胞的CD25及CD69,但IL-6的表达水平无明显变化;双荧光素酶报告实验提示VP-16通过NF-κB信号通路正向调控HIV-1 LTR的转录水平;WB结果表明VP-16能够抑制SIRT1的蛋白表达并促进NF-κB p65的乙酰化水平;慢病毒SIRT1-shRNA成功敲低J-Lat细胞中SIRT1的mRNA和蛋白表达,能够有效激活HIV-1潜伏感染。结论VP-16通过抑制SIRT1表达从而上调NF-κB p65的乙酰化水平,继而促进HIV-1 LTR的转录并最终激活HIV-1的潜伏感染。
简介:摘要:文明礼仪作为个人道德修养的重要组成部分,在幼儿教育中具有不可忽视的重要地位。3―6岁正是习惯养成的敏感时期,抓住这一关键时期的培养,对幼儿进行文明礼仪教育,使幼儿从小学礼、知礼、懂礼、用礼,将关系到幼儿一生的发展。
简介:摘 要:职业教育法的原则,是职业教育法遵循的基本要求和价值准则。新修订的《职业教育法》对基本原则进行了规定,更适应了中国特色社会主义新时代的要求,将支持经济和产业发展,培养高素质技术技能劳动者,完善现代职业教育体系融会贯通。
简介:【摘要】所谓三“从”四“得”的教学方法,四“得”是课堂教学流程的架构,是贯穿并指导学生整节课学习的导航主线,使之教学环节有条理,学习目的明确到位,而三“从”是四“得”的教学辅助,起到催化的作用,两者相辅相承,不可缺之。在小学信息技术课堂上运用三“从”四“得”的教学方法有效地促进LOGO课堂的教与学,提高了课堂的教学质量。
简介:摘要:目的:根据现状调查的数据分析可知,随机统计盐酸左氧氟沙星注射液39批成品得率数据,平均值仅为93.2%,最高值为96.8%,因此目标设定为将得率由93.2%提升至97.0%。