Dalecki D, Child S Z, Raeman C H, Penney D P, Mayer R, Cox C, Carstensen E L
Department of Electrical Engineering, University of Rochester, NY 14627, USA.
Ultrasound Med Biol. 1997;23(2):287-97. doi: 10.1016/s0301-5629(96)00212-8.
Hemorrhage to fetal tissues occurred when late-term pregnant mice were exposed to lithotripter fields of relatively low amplitude. These hemorrhages were always observed in tissues near developing bone or cartilaginous structures such as the head, limbs and ribs, while soft tissues distant from bone were relatively free of hemorrhage. Thresholds for hemorrhage in the fetus were determined for exposures of pregnant mice on the 18th day of gestation to 200 pulses from a piezoelectric lithotripter. Animals were exposed to axial peak positive pressures of either 0 (sham), 1, 2, 3, 5 or 10 MPa. Thresholds for hemorrhage to the head, limbs, ribs and lung were all < 1 MPa.
当晚期妊娠小鼠暴露于相对低振幅的碎石场时，胎儿组织会发生出血。这些出血总是在发育中的骨骼或软骨结构（如头部、四肢和肋骨）附近的组织中观察到，而远离骨骼的软组织相对没有出血。通过在妊娠第18天对怀孕小鼠暴露于压电碎石机的200个脉冲来确定胎儿出血的阈值。动物暴露于0（假手术）、1、2、3、5或10兆帕的轴向峰值正压下。头部、四肢、肋骨和肺部出血的阈值均<1兆帕。
