The genetic diversity and relationships of seven Chinese indigenous pig breeds （Meishan, Erhualian, Hezuo, Bamei, Qingping, Tongcheng, and Huainan） and three exotic pig breeds （Large White, Landrace, and Duroc） we...The genetic diversity and relationships of seven Chinese indigenous pig breeds （Meishan, Erhualian, Hezuo, Bamei, Qingping, Tongcheng, and Huainan） and three exotic pig breeds （Large White, Landrace, and Duroc） were analyzed using the DNA differential display technique by means of eight primer combinations. A total of 123 reproducible bands were used to calculate mean Nei＇s gene diversity, and mean Shannon＇s information index for each pig population. Based on these the Nei＇s standard genetic identity and distance were estimated, which was used to construct a dendrogram tree for the 10 pig breeds. The experimental results obtained and the method used in this study for evaluating the genetic diversity and relationships of pigs were also discussed.展开更多
Mutactimycin,a new anthracycline antibiotic,consists of 5 components: mutac-timycin A,B,C,D and 7-deoxymutactimycinone A. Mutactimycin components differ from each other in suppressing proliferation and inducing differ...Mutactimycin,a new anthracycline antibiotic,consists of 5 components: mutac-timycin A,B,C,D and 7-deoxymutactimycinone A. Mutactimycin components differ from each other in suppressing proliferation and inducing differentiation of human erythroleukemia K-562 cells. Determined by benzidine staining, the percentage of K-562 cells with hemoglobin expression was86% by mutactimycin C. The peak percentage of benzidine positive cells appeared on day 5 or 6.The differentiated cells were partially reversed after drug removal.The induced cells lost the clonogenicity in soft-agar. The kinetics of differentiation induced by mutactimycin C, in comparison with other known anthracycline antibiotics,was similar to that by doxorubicin, epirubicin anddaunorubicin. Mutactimycin C was more active than aclarubicin A. The structure-activity relationship for mutactimycin components suggested that the substituting groups on C_3, C_11, and the saccharide on C_7 might be important for their activities.展开更多
文摘The genetic diversity and relationships of seven Chinese indigenous pig breeds （Meishan, Erhualian, Hezuo, Bamei, Qingping, Tongcheng, and Huainan） and three exotic pig breeds （Large White, Landrace, and Duroc） were analyzed using the DNA differential display technique by means of eight primer combinations. A total of 123 reproducible bands were used to calculate mean Nei＇s gene diversity, and mean Shannon＇s information index for each pig population. Based on these the Nei＇s standard genetic identity and distance were estimated, which was used to construct a dendrogram tree for the 10 pig breeds. The experimental results obtained and the method used in this study for evaluating the genetic diversity and relationships of pigs were also discussed.
文摘Mutactimycin,a new anthracycline antibiotic,consists of 5 components: mutac-timycin A,B,C,D and 7-deoxymutactimycinone A. Mutactimycin components differ from each other in suppressing proliferation and inducing differentiation of human erythroleukemia K-562 cells. Determined by benzidine staining, the percentage of K-562 cells with hemoglobin expression was86% by mutactimycin C. The peak percentage of benzidine positive cells appeared on day 5 or 6.The differentiated cells were partially reversed after drug removal.The induced cells lost the clonogenicity in soft-agar. The kinetics of differentiation induced by mutactimycin C, in comparison with other known anthracycline antibiotics,was similar to that by doxorubicin, epirubicin anddaunorubicin. Mutactimycin C was more active than aclarubicin A. The structure-activity relationship for mutactimycin components suggested that the substituting groups on C_3, C_11, and the saccharide on C_7 might be important for their activities.
