一、急性毒性体重18～22g雄、雌小白鼠,腹腔给药观察3日内死亡数,以机率单位比例法求得LD50为92.92克生药/公斤。二、祛痰实验体重27～30g 雌、雄小白鼠,以气管内酚红排出量为指标。以野氏法测得桦树皮的(1/5)LD50剂量,测得祛痰结果为400%。注:给药组与对照组相比,以对照组酚红浓度为100%计算,给药组酚红浓度的百 First, acute toxicity weight 18 ~ 22g male and female mice, intraperitoneal administration to observe the number of deaths within 3 days, the odds ratio method to obtain the LD50 was 92.92 grams crude drug / kg. Second, the experimental weight of 27 ~ 30g female and male mice, the amount of phenol red discharge in the trachea as indicators. The (1/5) LD50 dose of birch bark was measured by the wild-type method, and the result of deuterium measurement was 400%. Note: Compared with the control group, the dose of phenol red in the control group is calculated as 100% of the phenol red concentration in the control group.