The old man ____ for three years. [ ]
A. has died
B. has been died
C. has been dead
答案:C
吸收铁的主要部位为()。
A.胃和结肠
B.胃和十二指肠
C.十二指肠和空肠上段黏膜
D.十二指肠和空肠
E.结肠和小肠
有出血倾向的患者行活髓牙牙髓治疗时常采用的局麻方法是
A.冷冻麻醉B.表面麻醉C.骨膜上浸润麻醉D.牙周膜注射浸润麻醉E.阻滞麻醉