I Factors affecting percutaneous absorption 1. Drug concentration is an important factor (药物浓度是一个重要因素。) 2. The larger the area of application, the more drug is absorbed. (当药物应用面积增大,经皮吸收的药物量 增加。)I. Factors affecting percutaneous absorption 1. Drug concentration is an important factor. （药物浓度是一个重要因素。） 2. The larger the area of application, the more drug is absorbed. （当药物应用面积增大，经皮吸收的药物量 增加。）