为了更系统地研究分散剂对无氰电沉积Ag/C复合层耐蚀性的影响,在以KI为配位剂的无氰电沉积Ag/C镀液中加入石墨粉和自制含羧基分散剂,在铜片表面电镀Ag/C复合层。利用扫描电镜和能谱仪分析了Ag/C复合镀层的表面形貌及成分;通过抗硫化变...为了更系统地研究分散剂对无氰电沉积Ag/C复合层耐蚀性的影响,在以KI为配位剂的无氰电沉积Ag/C镀液中加入石墨粉和自制含羧基分散剂,在铜片表面电镀Ag/C复合层。利用扫描电镜和能谱仪分析了Ag/C复合镀层的表面形貌及成分;通过抗硫化变色性能试验、Tafel极化曲线等研究了分散剂用量对复合镀层在SO2,H2S气体及Na2S,K2SO4溶液中腐蚀特性的影响。结果表明:分散剂最佳用量为5 m L/L,此时石墨在镀液及镀层中分散效果最好,所得镀层也最均匀、细致;镀液中含分散剂时所得Ag/C复合层在H2S,SO2气氛中及Na2S和K2SO4溶液中的抗硫化变色能力均较强。展开更多
AIM: To determine the role of interferon (IFN) with or without ribavirin in preventing or delaying hepatocellular carcinoma (HCC) development in patients with hepatitis C virus (HCV) related cirrhosis. Data on the pre...AIM: To determine the role of interferon (IFN) with or without ribavirin in preventing or delaying hepatocellular carcinoma (HCC) development in patients with hepatitis C virus (HCV) related cirrhosis. Data on the preventive effect of IFN plus ribavirin treatment are lacking.METHODS: A total of 101 patients (62 males and 39 females, mean age 55.1:1:1.4 years) with histologically proven HCV related liver cirrhosis plus compatible biochemistry and ultrasonography were enrolled in the study. Biochemistry and ultrasonography were performed every 6 too. Ultrasound guided liver biopsy was performed on all detected focal lesions. Follow-up lasted for 5 years. Cellular proliferation, evaluated by measuring Ag-NOR proteins in hepatocytes nuclei, was expressed as AgNOR-Proliferative index (AgNOR-PI) (cut-off = 2.5). Forty-one patients (27 males, 14 females) were only followed up after the end of an yearly treatment with IFN-alpha2b (old treatment control group = OTCG). Sixty naive patients were stratified according to sex and AgNOR-PI and then randomized in two groups: 30 were treated with IFN-alpha2b + ribavirin (treatment group=TG), the remaining were not treated (control group=CG). Nonresponders (NR) or relapsers in the TG received further IFN/ribavirin treatments after a 6 mo of withdrawal. RESULTS: AgNOR-PI was significantly lowered by IFN (P<0.001). HCC incidence was higher in patients with AgNOR-PI>2.5 (26% vs3%, P<0.01). Two NR in the OTCG, none in the TG and 9 patients in the CG developed HCC during follow-up. The Kaplan-Mayer survival curves showed statistically significant differences both between OTCG and CG (P<0.004) and between TG and CG (P<0.003). CONCLUSION: IFN/ribavirin treatment associated with retreatment courses of NR seems to produce the best results in terms of HCC prevention. AgNOR-PI is a useful marker of possible HCC development.展开更多
A rapid and sensitive colorimetric detection of ascorbic acid(AA)through the morphology transformation of silver triangular nanoplates(Ag TNPs)is developed.By virtue of the redox reaction among silver nitrate and A A,...A rapid and sensitive colorimetric detection of ascorbic acid(AA)through the morphology transformation of silver triangular nanoplates(Ag TNPs)is developed.By virtue of the redox reaction among silver nitrate and A A,the newly formed Ag atoms deposited on the surfaces of Ag TNPs.Subsequently,the morphology of Ag TNPs transforms from triangle to circle,resulting in a more than 160 nm blue shift of localized surface plasmon resonance absorption peak.The corresponding color of the solution converting from blue to yellow with the concentration of AA can be observed by naked eyes within 15 min.A linear relationship between the blue shift of absorption peak and the concentration of A A ranging from 0.2 to 6μM is obtained with a limit of detection(LOD)of 100 nM(3σ).Some potential species(e.g.,glucose,urea and various amino acids)coexisting in the system showed little or no interference.The proposed assay is successfully employed to determine the amount of A A in pharmaceutical products with recoveries from 96.9 to 106.5%and offers a sensitive,low-cost,rapid and simple assay of visual analysis of ascorbic acid.展开更多
文摘为了更系统地研究分散剂对无氰电沉积Ag/C复合层耐蚀性的影响,在以KI为配位剂的无氰电沉积Ag/C镀液中加入石墨粉和自制含羧基分散剂,在铜片表面电镀Ag/C复合层。利用扫描电镜和能谱仪分析了Ag/C复合镀层的表面形貌及成分;通过抗硫化变色性能试验、Tafel极化曲线等研究了分散剂用量对复合镀层在SO2,H2S气体及Na2S,K2SO4溶液中腐蚀特性的影响。结果表明:分散剂最佳用量为5 m L/L,此时石墨在镀液及镀层中分散效果最好,所得镀层也最均匀、细致;镀液中含分散剂时所得Ag/C复合层在H2S,SO2气氛中及Na2S和K2SO4溶液中的抗硫化变色能力均较强。
文摘AIM: To determine the role of interferon (IFN) with or without ribavirin in preventing or delaying hepatocellular carcinoma (HCC) development in patients with hepatitis C virus (HCV) related cirrhosis. Data on the preventive effect of IFN plus ribavirin treatment are lacking.METHODS: A total of 101 patients (62 males and 39 females, mean age 55.1:1:1.4 years) with histologically proven HCV related liver cirrhosis plus compatible biochemistry and ultrasonography were enrolled in the study. Biochemistry and ultrasonography were performed every 6 too. Ultrasound guided liver biopsy was performed on all detected focal lesions. Follow-up lasted for 5 years. Cellular proliferation, evaluated by measuring Ag-NOR proteins in hepatocytes nuclei, was expressed as AgNOR-Proliferative index (AgNOR-PI) (cut-off = 2.5). Forty-one patients (27 males, 14 females) were only followed up after the end of an yearly treatment with IFN-alpha2b (old treatment control group = OTCG). Sixty naive patients were stratified according to sex and AgNOR-PI and then randomized in two groups: 30 were treated with IFN-alpha2b + ribavirin (treatment group=TG), the remaining were not treated (control group=CG). Nonresponders (NR) or relapsers in the TG received further IFN/ribavirin treatments after a 6 mo of withdrawal. RESULTS: AgNOR-PI was significantly lowered by IFN (P<0.001). HCC incidence was higher in patients with AgNOR-PI>2.5 (26% vs3%, P<0.01). Two NR in the OTCG, none in the TG and 9 patients in the CG developed HCC during follow-up. The Kaplan-Mayer survival curves showed statistically significant differences both between OTCG and CG (P<0.004) and between TG and CG (P<0.003). CONCLUSION: IFN/ribavirin treatment associated with retreatment courses of NR seems to produce the best results in terms of HCC prevention. AgNOR-PI is a useful marker of possible HCC development.
基金Key Lab of Process Analysis and Control of Sichuan Universities(No.2019003)provided support for this projectsponsored by the Chongqing Talent Program(Leading Talent)
文摘A rapid and sensitive colorimetric detection of ascorbic acid(AA)through the morphology transformation of silver triangular nanoplates(Ag TNPs)is developed.By virtue of the redox reaction among silver nitrate and A A,the newly formed Ag atoms deposited on the surfaces of Ag TNPs.Subsequently,the morphology of Ag TNPs transforms from triangle to circle,resulting in a more than 160 nm blue shift of localized surface plasmon resonance absorption peak.The corresponding color of the solution converting from blue to yellow with the concentration of AA can be observed by naked eyes within 15 min.A linear relationship between the blue shift of absorption peak and the concentration of A A ranging from 0.2 to 6μM is obtained with a limit of detection(LOD)of 100 nM(3σ).Some potential species(e.g.,glucose,urea and various amino acids)coexisting in the system showed little or no interference.The proposed assay is successfully employed to determine the amount of A A in pharmaceutical products with recoveries from 96.9 to 106.5%and offers a sensitive,low-cost,rapid and simple assay of visual analysis of ascorbic acid.
