控释抗菌药物治疗牙周炎的优点（）。
A.用药剂量小
B.局部浓度高
C.维持时间长
D.疗效高
E.以上均是
参考答案：E
仿照例子，将下列句子改成否定句。
Model: I am a teacher. (student) → I'm not a student.
1. I like pork. (cabbages) →
2. They are healthy. (sour) →
3. The book is on the desk. (chair) →
4. Today is Sunday. (Monday) →
5. You are tall. (short) →
属于乳腺癌高危人群的是（）
A.喜吃素食
B.25岁生育并母乳喂养
C.母亲患乳腺癌
D.绝经于48岁
E.月经初潮于15岁
