第7题: [单项选择]下列选项中,提示骨肿瘤为恶性的X线表现是 A. 界限清楚 B. 三角形骨膜反应 C. 病灶周围硬化反应骨 D. 骨皮质膨胀变薄 参考答案:B 答案解析:良性骨肿瘤具有界限清楚,密度均匀的特点。肿瘤多为外生性生长,速度缓慢,可以有皮质膨胀变薄,形成膨胀性骨病损。病灶周围可有硬化反应骨,骨质破坏呈单房性或多房性,内有点状、环状、片状骨化影,通常无骨膜反应
第28题: [单项选择]For decades, milk was considered a luxury drink because common people ______. A. did not like drinking milk B. were not used to drinking milk C. could find no way to get milk D. could not afford drinking milk 参考答案:D