In the 1970s,activities for immunity from diseases were carried out during winters and springs,and in 1978 work on planned immunity for children was started on a nationwide scale.

 
  • 七十年代每年利用冬春季节开展免疫活动,并于1978年开始在全国范围内普及儿童计划免疫工作。
今日热词
目录 附录 查词历史