Unit head circumference maximum and mean blood flow velocities per minute of fetal middle cerebral artery were changed little during the normal second trimester.
每分钟单位头围大脑中动脉的最大速度及平均速度在中孕期间变化小。
3
The surface area of aggregate perunit volume of mortar does have influence on the mean value of the nearest surface spacing, but the ratio between them is not constant.