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AIM: To study the effect of fibroblast growth factor receptor 1 (FGFR1) expression knock-down on the viability, apoptosis, invasion and migration of infantile hemangioma endothelial cells (HemECs). METHODS: FGFR1 was down-regulated by FGFR1 small interfering RNA (si-FGFR1) transfection. The viability of the cells was measured by CCK-8 assay. The apoptotic rate was analyzed by flow cytometry and the invasion and migration abilities were determined by Transwell assay. The protein levels of phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), and phosphorylated AKT (p-AKT) were examined by Western blot. RESULTS: Transfection of si-FGFR1 into HemECs had significant effects on inhibiting cell viability (P<0.05), promoting apoptosis (P<0.05), and decreasing cell invasion and migration abilities (P<0.05). The results of Western blot showed that knockdown of FGFR1 gene expression in the cells reduced the protein levels of PI3K and p-AKT (P<0.05), and had no significant effect on AKT protein level. CONCLUSION: Knock-down of FGFR1 expression changes the biological characteristics of endothelial cells in infantile hemangiomas by regulating PI3K/AKT signaling pathway. 相似文献
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Samples from combinations of different alcoholic extraction process parameters of rice bran oil, solvents (ethanol or isopropanol) and temperatures (60 or 80 °C) were evaluated and compared with samples from industrial processing regarding the physicochemical, structural and functional characteristics of the defatted meal since these properties are directly associated with the quality of the products. The results obtained for solids from alcoholic extraction did not differ significantly from those obtained from industrial processing using hexane. Although the use of alcohols and high temperatures led to reductions in the nitrogen solubility (21% to 13.5–16.7%), emulsifying activity (31% to 14–25%) and thermal stability, possibly as a function of protein structural modifications due to denaturation, stable foams were produced (26–50%), and adequate values for the water and oil absorption capacities were determined (4 and 3 g/g sample), allowing the application of this material in baking and meat products. 相似文献
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针对LNG泄漏在地面上潜在危险的分析,需要对其在地面上扩散和蒸发速率的变化进行准确预测。基于液体扩散的动力学模型和热传递模型,采用微分方法建立了LNG在连续性泄漏情况下液池漫延半径、蒸发速率随时间变化的预测模型,克服了现有预测模型单纯依赖一维傅里叶导热方程的局限性。根据所建立的预测模型,LNG液池蒸发速率先随时间线性增加到最大值,随后随时间的延长而降低,即与时间的平方根成反比。以5m^3圆柱形LNG储罐为例,计算得到LNG泄漏的速率为19.92kg/s,泄漏完全所需时间为69S,液池半径达到最大的时间为33S,液池半径最大值为7m,0~33S时间内LNG蒸发速率先线性达到最大值19.92kg/s,34-69s时间内液池蒸发速率与时间平方根成反比,液池厚度由2.3mm逐渐增加到6mm。 相似文献
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The bio-control potential of arbuscular mycorrhizal fungus Glomus mosseae against two pathogenic microorganisms aster yellows (AY) phytoplasma and Spiroplasma citri has been examined in Madagascar periwinkle (Catharanthus roseus). G. mosseae had a positive influence on healthy C. roseus plants and S. citri infection. It provided bioprotection against S. citri pathogen and induced significant degree of resistance to spiroplasma infection. Besides, symptom expression significantly reduced and shoot height, leaves number, root fresh and dry weight increased in spiroplasma-infected plants treated with mycorrhiza fungus. Although, G. mosseae had no positive effect on phytoplasma disease. The root architectures were affected by the phytoplasma pathogen, and the root surface area dramatically decreased in G. mosseae treated AY-infected periwinkles compared with the control. Nitrogen and Phosphorus concentrations notably increased in spiroplasma + G. mosseae compared with control plants. Potassium concentration did not differ significantly in all mycorrhizal treated and untreated infected plants except in G. mosseae treated healthy plants. The spore density and root colonization rate did not vary in both pathogen treatments G. mosseae + spiroplasma and G. mosseae + phytoplasma. To our knowledge, this is the first report showing the bioprotective effect of G. mosseae on S. citri. The possible mechanisms involved in complex interaction between plants, cell wall-less bacteria and arbuscular mycorrhizal fungi (AMF) are discussed and the underlying mechanisms for the functioning of AMF are hypothesized. 相似文献
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4种不同性诱剂对玉米草地贪夜蛾诱集作用 总被引:4,自引:0,他引:4
为准确掌握草地贪夜蛾成虫发生动态,筛选对当地种群专一性强、灵敏度高的性诱剂,对深圳百乐宝生物农业科技有限公司(BLB)、宁波纽康生物技术有限公司(NK)、江苏宁录科技股份有限公司(NL)、南京新安中绿生物科技有限公司(XAZL)4个厂家生产的草地贪夜蛾性诱剂在江苏盐城市大丰区进行田间诱捕效果试验,探讨草地贪夜蛾性诱剂的使用技术。结果表明:4种不同性诱剂诱芯对草地贪夜蛾的诱集效果存在明显差异。BLB诱芯和NL诱芯可以有效监测草地贪夜蛾成虫田间发生动态,羽化高峰期明显,且峰值日期一致,NK诱芯诱集的成虫虫峰不明显,XAZL诱芯零星诱到成虫,无明显成虫高峰;BLB诱芯监测期内日均诱蛾量、最高单次诱蛾量、总诱蛾量均显著高于其他3种诱芯,其总诱蛾量达136.75头,分别是NL诱芯、NK诱芯、XAZL诱芯的1.47倍、4.76倍、10.52倍;通过对BLB诱芯进行持续30 d和持续60 d的诱捕对比试验,发现BLB诱芯1~30 d内诱捕性能稳定,诱蛾量大,31~60 d内日均诱蛾量、最高单次诱蛾量、总诱蛾量均有所下降且达显著水平,尤其是50 d后诱捕量下降明显。结果表明:BLB诱芯的诱蛾量大,能够明显反映出草地贪夜蛾的羽化高峰期,符合测报要求,更适合本地区草地贪夜蛾的监测,使用该诱芯时建议30 d更换1次。 相似文献
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利用膜进样质谱仪测定水稻土几种厌氧氮转化速率 总被引:3,自引:1,他引:2
为了在同一体系下区分和测定水稻土反硝化、厌氧氨氧化(Anammox)和硝酸根异化还原成铵(DNRA)过程发生速率和相互关系,并获取近似原位情况下的净脱氮速率,本研究通过将~(15)NH_4~+化学氧化法测定DNRA速率和添加尿素模拟原位土柱测定净脱氮速率与膜进样质谱法(MIMS)进行联用,完善了一套基于膜进样质谱法(MIMS)的稻田硝态氮转化测定方法体系,利用该方法测定了5种典型的水稻土[辽宁营口(YK)、江苏宜兴(YX)、浙江金华(JH)、广西桂林(GL)和四川广安(GA)]的反硝化、Anammox、DNRA和净脱氮4种氮转化速率。结果显示:基于MIMS的方法体系可实现对水稻土中反硝化、Anammox、DNRA和净脱氮速率的测定,5种水稻土反硝化、Anammox、DNRA和净脱氮速率范围分别为(358.63±25.37)~(479.96±22.12)、(-14.81±0.22)~(5.29±1.22)、(25.76±12.71)~(109.87±3.88)g N·hm~(-2)·h~(-1)和(33.33±11.16)~(72.74±14.18)g N·hm~(-2)·h~(-1),相关结果与其他方法研究结果具有可比性。相关性分析显示:水稻土NO_3~-、可溶性有机碳(DOC)和土壤Fe~(2+)含量是反硝化过程的主要限制因素;NO_3~-是Anammox的关键限制因素;而土壤DOC和Fe~(2+)含量是DNRA过程的主要限制因素。基于MIMS的方法体系可以在短时间内(1周)测定水稻土四种厌氧氮转化速率,且所需样品量低、精确度高,在稻田或湿地土壤厌氧氮转化过程研究中有很好的应用前景。 相似文献
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热误差是影响机床加工精度的主要因素之一。主轴的热变形是机床总的热变形的重要组成部分。因此本文在分析数控铣齿机主轴热源的基础上,计算发热量,确定边界条件,并利用有限元软件abaqus建立主轴系统的温度场模型并进行了数字模拟仿真,为主轴系统的进一步热变形控制提供了基础。 相似文献
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