我国先秦时期形成了较为系统的农业减灾救荒思想，它包含灾前预防思想、农业减灾思想和灾后救荒思想三大部分。
It includes three important aspects, the idea of agricultural disasters prevention, the idea of agricultural disasters reduction and the idea of famine relief.
这一策略被称为“暴露前预防”(PrEP)，是建立在这样的概念基础上：在接触病毒之后立即阻断HIV的自我复制可以预防感染。
This strategy, known as pre-exposure prophylaxis, or PrEP, is based on the concept that blocking HIV's replication immediately after exposure to the virus may prevent infection.
妊娠脊柱前凸也是同样可以预防不良体态。
Hyperlordosis of pregnancy is the same preventable bad posture.
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