血管造影的并发症中哪个除外
A．穿刺部位血肿B．假性动脉瘤C．血管内膜剥离D．原发病加重E．血管破裂
参考答案：D
在正位X线片上，椎体的影像学表现不包括（）
A.呈长方形
B.骨皮质密度均匀
C.轮廓光滑
D.中间为骨松质
E.骨小梁呈横行
Every possible means ________ to prevent the air pollution, but the sky is still not clear. [ ]
A. is used
B. are used
C. has been used
D. have been used
