爬行类的鳞片和鱼类的鳞片都是由皮肤的真皮层演化而来。()
参考答案:错
解析:将整句改为“爬行类的磷片由表皮层衍化而来,而鱼类的磷片由真皮层衍化而来。”
No other countries could _____, nor could slaves _____ women. [ ]
A. join; or
B. join in; or
C. join; and
D. join in; and
男,28岁。右膝内侧逐渐隆起伴隐痛半年。X片示:右胫骨干骺端有一破坏区,边缘呈膨胀性改变,中央有肥皂泡样阴影。诊断首先考虑()
A.软骨骨瘤
B.骨巨细胞瘤
C.骨肉瘤
D.骨转移性癌
E.骨囊肿