目的在临床随访研究中,基于时间尺度指标的限制平均生存时间(restricted mean survival time,RMST)越来越受到关注,然而目前基于RMST的统计推断主要用于两组比较,缺少进行两组以上比较的方法。方法本文提出RMST多组间的假设检验法,包括...目的在临床随访研究中,基于时间尺度指标的限制平均生存时间(restricted mean survival time,RMST)越来越受到关注,然而目前基于RMST的统计推断主要用于两组比较,缺少进行两组以上比较的方法。方法本文提出RMST多组间的假设检验法,包括经典法(naive)、对数转换法(log)、双对数转换法(cloglog)三种检验法,并通过Monte Carlo模拟评价其Ⅰ类错误和检验效能,最后进行实例分析。结果综合Monte Carlo模拟的Ⅰ类错误及检验效能结果,显示所提出的RMST检验可以处理多组比较的问题,特别是cloglog转换法最为稳健。结论针对生存数据的多组比较问题,若考虑从时间尺度指标分析,推荐使用cloglog转换法的RMST多组检验。展开更多
[Objectives]This study was conducted to investigate the effects of different nutrient solutions on the parasitism of Cuscuta grandis to Mikania micrantha.[Methods]The growth-promoting effect of C.reflexa parasitizing ...[Objectives]This study was conducted to investigate the effects of different nutrient solutions on the parasitism of Cuscuta grandis to Mikania micrantha.[Methods]The growth-promoting effect of C.reflexa parasitizing M.micrantha was studied through the use of different concentrations of plant growth regulators(naphthalene acetic acid,gibberellic acid)and compounds containing trace elements(manganese sulfate,copper sulfate,zinc nitrate,boric acid).[Results]Mixing naphthalene acetic acid with a concentration of 0.01 ml/L and gibberellic acid with a concentration of 1 mg/L at a ratio of 1∶3 and then adding an equal volume of compounds containing trace elements including manganese sulfate with a concentration of 0.1 mg/L,copper sulfate with a concentration of 0.1 mg/L,zinc nitrate with a concentration of 0.1 mg/L and boric acid with a concentration of 2 mg/L,the average stem length of the breeding group increased significantly,about 2.47 cm,showing a significant difference from the CK.The survival rate of the experimental group using the plant growth regulators and the trace elements was 66.67%,and the survival rate of the control group was 56.67%.[Conclusions]This study can fill the gap in the study of seed morphology of C.reflexa,and is also of great significance for the identification and quarantine of C.reflexa.展开更多
基金Supported by Yunnan Forestry Technological College Fund[(KY(YB)201925)]Special Fund for Scientific Research in Forestry Public Welfare Industry(201204518)。
文摘[Objectives]This study was conducted to investigate the effects of different nutrient solutions on the parasitism of Cuscuta grandis to Mikania micrantha.[Methods]The growth-promoting effect of C.reflexa parasitizing M.micrantha was studied through the use of different concentrations of plant growth regulators(naphthalene acetic acid,gibberellic acid)and compounds containing trace elements(manganese sulfate,copper sulfate,zinc nitrate,boric acid).[Results]Mixing naphthalene acetic acid with a concentration of 0.01 ml/L and gibberellic acid with a concentration of 1 mg/L at a ratio of 1∶3 and then adding an equal volume of compounds containing trace elements including manganese sulfate with a concentration of 0.1 mg/L,copper sulfate with a concentration of 0.1 mg/L,zinc nitrate with a concentration of 0.1 mg/L and boric acid with a concentration of 2 mg/L,the average stem length of the breeding group increased significantly,about 2.47 cm,showing a significant difference from the CK.The survival rate of the experimental group using the plant growth regulators and the trace elements was 66.67%,and the survival rate of the control group was 56.67%.[Conclusions]This study can fill the gap in the study of seed morphology of C.reflexa,and is also of great significance for the identification and quarantine of C.reflexa.