侧凹凸塑件的抽芯注射模具，一般情况下，这类模具设计成外置抽芯机构。对于架子塑料制件。充分利用塑件内部空间大，抽芯距离小的特点，设......

AIM:To determine which modification to a vascular puncture needle results in increased visualization during ultrasound(U......