The actue toxic effect of heavy metal Cu ~ ( 2 + ) to Stentor Polymorphrus ( Ciliophora, Heterotrichida ) was studied. 研究了重金属铜对异毛目纤毛虫多态喇叭虫 ( Stentor polymorphrus ) 的急性毒性影响.
After the 1960 s, China began to inoculate BCG, pertussis, diphtheria, tetanus, measles and poliomyelitis vaccines.六十年代后, 中国开始在大、中城市接种卡介苗 、 百日咳 、 白喉 、 破伤风 、 麻疹、脊髓灰质炎的疫苗的工作.The prompt administration of diphtheria antitoxi...
The Sahara Desert is arid.撒哈拉沙漠非常干燥.A petroglyph emerges from the Sahara Desert.这是撒哈拉大沙漠里的一块岩石画。The Sahara Desert is a natural barrier between North and Central Africa.撒哈拉沙漠是北非与中非之间的天然屏障....