Things have changed a lot ____ I wrote to you last time.
A.when
B.since
C.as
D.before
答案:B
烧结空心砖,其特点是:孔洞个数少但洞腔较大,孔洞率在( )以上,孔洞垂直于顶面,平行于大面。
A.20%
B.25%
C.30%
D.35%
骨巨细胞瘤的典型征象是()
A.位于干骺端的膨胀性偏心性囊性骨破坏,内有肥皂泡样骨间隔
B.骨端的囊性破坏区,其透光区模糊,皮质变薄
C.远距骨干骺端的偏心性囊性骨破坏,边缘硬化
D.位于骨骺多发性骨质破坏,内有钙化
E.丝瓜瓤样改变