鼓膜来源于何组织()A．外胚层——上皮层 B．中胚层——纤维层 C．内胚层——粘膜层

It was reported in the newspaper that one of our students got the first place in the last Provincial Chemistry

Olympic Contest _____ in June. [ ]

A. having been held

B. to be held

C. being held

D. held

天车经常超载起吊和不合理使用，会使主梁材质疲劳，降低材料屈服点，使其抵抗变形的能力降低，从而使天车主梁产生下挠。

脊柱骨折最严重的并发症()

A．脂肪栓塞

B．骨筋膜室综合征征

C．压疮

D．脊髓损伤

E．周围神经损伤

下列何项是诊断肾病综合征的必须条件

A．尿蛋白＞3.g/d

B．尿沉渣红细胞计数＞3个，高倍视野

C．高血压

D．水肿

E．血脂升高