text_1: 我们 按照 筛选 时 的 一线 治疗 结局 和 肿瘤 BRCA 状态 分层 , 利用 区组 设计 集中 进行 了 随机化 ( 见 补充 附录 ) .
  
text_2: randomization was performed centrally with the use of a block design with stratification according to the outcome of first @-@ line treatment at screening and tumor BRCA status ( see the Supplementary Appendix ) .
  