何为高压氧与高压氧疗法。
参考答案：
机体处于高气压环境中所呼吸的与环境压相等的纯氧或高浓度氧，称为高压氧。利用吸入高压氧治疗疾病的方法称为高压氧疗法。
—How about going shopping this weekend , Peter?
—Sorry. I prefer _ rather than _ . [ ]
A. to stay at home ; go out
B. to go out; stay at home
C. staying at home; go out
D. going out; stay at home
罹患率为
A．观察期内新旧病例数/同期暴露人口数×100%
B．观察期内新病例数/同期暴露人口数×100%
C．观察期内新旧病例数/同期平均人口数×100%
D．观察期内病例数/同期平均人口数×100%
E．一年内的新病例数/同年暴露人口数×100%
