There were no reported cases after that, and so by the late '70s, the world was certified sort of free of smallpox worldwide.
在那之后就再也没有过报告,到七十年代晚些时候,已经确认世界各国都摆脱了天花
耶鲁公开课 - 生物医学工程探索课程节选
应用推荐
模块上移
模块下移
不移动