Observe spirit, food taken, night soil and weight of the rats during the experiment.

中文解释

由于当时社会缺乏现代卫生意识和控制机制，对粪便处理和农用放任自流，血吸虫卵经粪便大量进入水网。

正在查询

gynecological detectives cryptical bp fine future besmirch surplus value rationing 如何 Qatari