【判断题】过曲线网格( Through Curve Mesh )命令所选的主截面线串和交叉线串必须相交。
【单选题】科学家 Edward Jenner发明了
【判断题】The pioneer of smallpox vaccine was Edward Jenner.
【多选题】Jenner Edward (1749-1823)发明接种牛痘预防天花的研究,下列说法正确的是:
【单选题】辅食添加及营养指导、成长发育评价工作属于
【单选题】How did Dr. Edward Jenner solve the problem of smallpox?
A.
He kept on focusing on people who had smallpox.
B.
He changed his way of thinking by turning to people without smallpox.
C.
Dairymaids advised that he use cowpox to experiment.
D.
He happened to discover cowpox and he experimented with it on dairymaids.
【单选题】Wann hat Edward Jenner ein Experiment gemacht?
【多选题】Jenner Edward (1749-1823)发明接种牛痘预防天花的研究证明了什么问题?
C.
疫苗的研制只能通过现场试验得到预防疾病的证据