We prepare a well-defined C84 monolayer on the surface of Ag （111） and study the geometric structure by scanning tunneling microscopy （STM）. The C84 molecules form a nearly close-packed incommensurate R30° la...We prepare a well-defined C84 monolayer on the surface of Ag （111） and study the geometric structure by scanning tunneling microscopy （STM）. The C84 molecules form a nearly close-packed incommensurate R30° lattice. The lattice is long-distance ordered with numerous local disorders. The monolayer exhibits complex bright/dim contrast; the largest height difference between the molecules can be greater than 0.4 nm. Annealing the monolayer at 380 ℃ can desorb part of the molecules, but more than sixty percent molecules stay on the Ag （111） surface even after the sample has been annealed at 650 ℃. Our analyses reveal that the 7-atom pits form beneath many molecules. Some other molecules sit at the 1-atom pits. Ag adatoms （those removed substrate atoms, accompanying the pit formation） play a very important role in this system. The adatoms can either stabilize or destabilize the monolayer, depending on the distribution manner of the adatoms at the interface. The distribution manner is determined by the co-play of the following factors： the dimension of the interstitial regions of the C84 overlayer, the number of the adatoms, and the long-distance migration of part adatoms.展开更多
目的比较HIV抗体明胶颗粒凝集检测法(Micro Liquid HIV PA,ML-PA)与BED-CEIA法在新近感染HIV患者中的检测结果,为ML-PA法的临床应用提供经验。方法对确认为HIV阳性的300例新报告感染者及132例长期感染样本分别用两种方法进行新近感染检...目的比较HIV抗体明胶颗粒凝集检测法(Micro Liquid HIV PA,ML-PA)与BED-CEIA法在新近感染HIV患者中的检测结果,为ML-PA法的临床应用提供经验。方法对确认为HIV阳性的300例新报告感染者及132例长期感染样本分别用两种方法进行新近感染检测,获得2009-2011年第二季度常规检测新报告感染者及吸毒人群、男男同性恋人群新近感染比例。结果 300例新报告感染者样本中259例样本被两种方法同时判定为HIV长期感染,有4例样本被同时判定为HIV新近感染,两种方法对HIV-1是否为新近感染和长期感染结果判定不同(P=0.012<0.05)且一致性较差(Kappa值=0.127);对132例长期感染的样本检测结果显示,BED-CEIA法中128例判为长期感染,而ML-PA法中131例判定为长期感染。对2009-2011年第二季度常规检测新报告感染者及吸毒人群、男男性行为人群用两种方法进行检测得出结果显示流行趋势相同。结论两种方法检测新近感染结果显示一致性较差,但是可以用两种方法共同分析新近感染比例,ML-PA法可以进行更多、更大范围的应用。展开更多
To investigate the effects of oxidative stress on substantia nigra neuronal degeneration and death in patients with Parkinson＇s disease, we treated neuroblastoma cells （SK-N-SH） and glioma cells with Fenton＇s reag...To investigate the effects of oxidative stress on substantia nigra neuronal degeneration and death in patients with Parkinson＇s disease, we treated neuroblastoma cells （SK-N-SH） and glioma cells with Fenton＇s reagent, iron chelating agent, neuromelanin and dopamine melanin. We investigated the changes in expression of nine oxidative stress-related genes and proteins. The levels of mRNAs for heme-oxygenase-1 and glutathione S-transferase-ml were significantly reduced in SK-N-SH cells exposed to oxidative stress, and increased in glial cells treated with deferoxamine. These results revealed that SK-N-SH neurons react sensitively to oxidative stress, which implies different outcomes between these two types of cells in the substantia nigra. Moreover, the influences of neuromelanin and dopamine melanin on cell function are varied, and dopamine melanin is not a good model for neuromelanin.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11079028 and 11374258)
文摘We prepare a well-defined C84 monolayer on the surface of Ag （111） and study the geometric structure by scanning tunneling microscopy （STM）. The C84 molecules form a nearly close-packed incommensurate R30° lattice. The lattice is long-distance ordered with numerous local disorders. The monolayer exhibits complex bright/dim contrast; the largest height difference between the molecules can be greater than 0.4 nm. Annealing the monolayer at 380 ℃ can desorb part of the molecules, but more than sixty percent molecules stay on the Ag （111） surface even after the sample has been annealed at 650 ℃. Our analyses reveal that the 7-atom pits form beneath many molecules. Some other molecules sit at the 1-atom pits. Ag adatoms （those removed substrate atoms, accompanying the pit formation） play a very important role in this system. The adatoms can either stabilize or destabilize the monolayer, depending on the distribution manner of the adatoms at the interface. The distribution manner is determined by the co-play of the following factors： the dimension of the interstitial regions of the C84 overlayer, the number of the adatoms, and the long-distance migration of part adatoms.
文摘目的比较HIV抗体明胶颗粒凝集检测法(Micro Liquid HIV PA,ML-PA)与BED-CEIA法在新近感染HIV患者中的检测结果,为ML-PA法的临床应用提供经验。方法对确认为HIV阳性的300例新报告感染者及132例长期感染样本分别用两种方法进行新近感染检测,获得2009-2011年第二季度常规检测新报告感染者及吸毒人群、男男同性恋人群新近感染比例。结果 300例新报告感染者样本中259例样本被两种方法同时判定为HIV长期感染,有4例样本被同时判定为HIV新近感染,两种方法对HIV-1是否为新近感染和长期感染结果判定不同(P=0.012<0.05)且一致性较差(Kappa值=0.127);对132例长期感染的样本检测结果显示,BED-CEIA法中128例判为长期感染,而ML-PA法中131例判定为长期感染。对2009-2011年第二季度常规检测新报告感染者及吸毒人群、男男性行为人群用两种方法进行检测得出结果显示流行趋势相同。结论两种方法检测新近感染结果显示一致性较差,但是可以用两种方法共同分析新近感染比例,ML-PA法可以进行更多、更大范围的应用。
基金the National Natural Science Foundation of China, No. 30600201the Tianjin Science and Technology Committee, No. 07JCYBJC09900
文摘To investigate the effects of oxidative stress on substantia nigra neuronal degeneration and death in patients with Parkinson＇s disease, we treated neuroblastoma cells （SK-N-SH） and glioma cells with Fenton＇s reagent, iron chelating agent, neuromelanin and dopamine melanin. We investigated the changes in expression of nine oxidative stress-related genes and proteins. The levels of mRNAs for heme-oxygenase-1 and glutathione S-transferase-ml were significantly reduced in SK-N-SH cells exposed to oxidative stress, and increased in glial cells treated with deferoxamine. These results revealed that SK-N-SH neurons react sensitively to oxidative stress, which implies different outcomes between these two types of cells in the substantia nigra. Moreover, the influences of neuromelanin and dopamine melanin on cell function are varied, and dopamine melanin is not a good model for neuromelanin.
