目的 研究CD1a和CD83阳性树突状细胞(DC)在慢性阻塞性肺疾病(COPD)小鼠肺组织中的分布及意义。方法 将20只C57BL/6小鼠采用随机数字表法分为空气对照组和烟熏COPD组,各10例。空气对照组暴露于空气中;烟熏COPD组使用香烟烟熏法建立COPD...目的 研究CD1a和CD83阳性树突状细胞(DC)在慢性阻塞性肺疾病(COPD)小鼠肺组织中的分布及意义。方法 将20只C57BL/6小鼠采用随机数字表法分为空气对照组和烟熏COPD组,各10例。空气对照组暴露于空气中;烟熏COPD组使用香烟烟熏法建立COPD小鼠模型,于最后一次烟熏结束24 h内处死小鼠,取右下肺。观察2组小鼠体质量变化、肺组织病理变化,测量平均内衬间隔(MLI),免疫组化法检测肺组织中CD1a^(+)、CD83^(+)DC的分布并计数。结果 建模7、14、21、28 d时烟熏COPD组的小鼠体质量较空气对照组均降低(P<0.05);HE染色示烟熏COPD组小鼠肺组织正常肺泡结构破坏,多个肺泡相互融合形成较大的肺泡腔,肺泡间隔有大量炎性细胞浸润,肺泡壁增厚,COPD造模成功;与空气对照组比较,烟熏COPD组MLI值(μm)增大(28.30±3.47 vs. 50.40±3.60),肺组织中CD1a^(+)DC数量(个/视野)增多(9.58±2.18 vs. 17.08±3.67),而CD83^(+)DC数量(个/视野)减少(19.78±4.95 vs. 8.02±3.30),差异有统计学意义(均P<0.05)。结论 烟熏COPD组小鼠肺组织CD1a^(+)DC增多,CD83^(+)DC减少,香烟烟熏可能导致DC成熟障碍。展开更多
The Eu 3+ doped Na 24 As 2Mo 22 O 83 phosphor was prepared by solid state reaction from Na 3AsO 4·12H 2O?Na 2MoO 4·2H 2O and MoO 3,and characterized by using elemental analysis,infrared spectroscopy and powd...The Eu 3+ doped Na 24 As 2Mo 22 O 83 phosphor was prepared by solid state reaction from Na 3AsO 4·12H 2O?Na 2MoO 4·2H 2O and MoO 3,and characterized by using elemental analysis,infrared spectroscopy and powder X ray diffractometry.According to our measurements with X ray diffraction,this material belongs to orthorhombic system with its lattice contants:a=1.4824nm,b=1.1902nm,c=1.1042nm,that are consistent with space group D 4 2 P2 12 12 1(No.19).The emission and excitation spectra were also measured.The luminescence properties of Eu 3+ doped Na 24 As 2Mo 22 O 83 and energy transfer mechanism were discussed.展开更多
文摘为了研究时效强化对稀土镁合金磨损机理和摩擦变形行为的影响,采用挤压工艺制备GW83(Mg-8Gd-3Y-0.5Zr,质量分数/%)稀土镁合金。利用电子万能试验机测试合金的室温力学性能,利用光学显微镜(optical microscope,OM)、扫描电子显微镜(scanning electron microscope,SEM)、透射电子显微镜(transmission electron microscope,TEM)观察分析合金的组织,利用球-盘式干滑动摩擦磨损试验机测试分析合金的耐磨性能。结果表明:经过T5峰时效处理后,析出了大量透镜状β′相,硬度和抗拉强度分别为124.1HV和420.31 MPa,相比在挤压态(O态)时有明显的增加。在实验载荷范围内,随着载荷的增加,合金的摩擦因数逐渐降低,磨损率逐渐增加。T5处理可显著降低GW83镁合金的磨损体积,提高耐磨性能。耐磨性能的提升与磨损机制及摩擦变形程度的改变有关。在5~10 N时,两种样品的主要磨损机制均为磨粒磨损、氧化磨损与黏着磨损。当载荷增加至20 N,O态样品的主要磨损机制转变为剥层磨损,而T5态样品直至80 N才出现轻微剥层磨损机制。T5处理显著减小了由摩擦引起的表层金属变形程度和变形层厚度,减少了摩擦裂纹的产生。
文摘目的 研究CD1a和CD83阳性树突状细胞(DC)在慢性阻塞性肺疾病(COPD)小鼠肺组织中的分布及意义。方法 将20只C57BL/6小鼠采用随机数字表法分为空气对照组和烟熏COPD组,各10例。空气对照组暴露于空气中;烟熏COPD组使用香烟烟熏法建立COPD小鼠模型,于最后一次烟熏结束24 h内处死小鼠,取右下肺。观察2组小鼠体质量变化、肺组织病理变化,测量平均内衬间隔(MLI),免疫组化法检测肺组织中CD1a^(+)、CD83^(+)DC的分布并计数。结果 建模7、14、21、28 d时烟熏COPD组的小鼠体质量较空气对照组均降低(P<0.05);HE染色示烟熏COPD组小鼠肺组织正常肺泡结构破坏,多个肺泡相互融合形成较大的肺泡腔,肺泡间隔有大量炎性细胞浸润,肺泡壁增厚,COPD造模成功;与空气对照组比较,烟熏COPD组MLI值(μm)增大(28.30±3.47 vs. 50.40±3.60),肺组织中CD1a^(+)DC数量(个/视野)增多(9.58±2.18 vs. 17.08±3.67),而CD83^(+)DC数量(个/视野)减少(19.78±4.95 vs. 8.02±3.30),差异有统计学意义(均P<0.05)。结论 烟熏COPD组小鼠肺组织CD1a^(+)DC增多,CD83^(+)DC减少,香烟烟熏可能导致DC成熟障碍。
文摘The Eu 3+ doped Na 24 As 2Mo 22 O 83 phosphor was prepared by solid state reaction from Na 3AsO 4·12H 2O?Na 2MoO 4·2H 2O and MoO 3,and characterized by using elemental analysis,infrared spectroscopy and powder X ray diffractometry.According to our measurements with X ray diffraction,this material belongs to orthorhombic system with its lattice contants:a=1.4824nm,b=1.1902nm,c=1.1042nm,that are consistent with space group D 4 2 P2 12 12 1(No.19).The emission and excitation spectra were also measured.The luminescence properties of Eu 3+ doped Na 24 As 2Mo 22 O 83 and energy transfer mechanism were discussed.
