密度制约因素
参考答案:当某一因素以百分比表示的不利效应(如死亡率)随种群密度的增大而增大或减小时,这种因素就是密度制约因素,如生物种间的捕食、寄生、食物、竞争等。
A hospitalized client craves a drink while withdrawing from alcohol. Which of the following measures is the best way to help the client resist the urge to drink
A. A routine search of visitors.B. A locked-door policy.C. One-to-one supervision by the staff.D. Support from other alcoholic clients.
有关布比卡因的心脏毒性反应,以下叙述哪项正确()。
A.血管内误入逾量的布比卡因对心律失常有一定治疗作用
B.妊娠妇女对布比卡因的心脏毒性不敏感
C.布比卡因引起的心血管意外,复苏困难
D.可以用利多卡因纠正布比卡因引起的室性心律失常
E.酸中毒和缺氧降低布比卡因的心脏毒性