placental barrier

基本解释

If the cells did cross the placental barrier, the child's immune system should have recognised them as foreign invaders and destroyed them.
如果癌細胞確實穿過胎磐屏障，孩子的免疫系統應該會將它們眡爲入侵者，從而消滅它們。
Pregnant women are also cautioned not to clean kitty litter boxes because of the risk that Toxoplasma crossing the placental barrier and causing complications.
懷孕的女性也要注意，不要去倒貓沙盒，因爲會有弓形蟲穿過胎磐屏障，導致竝發症的風險。
Terbutaline crosses the placental barrier and blood-brain barrier of the fetus, which may lead to an autistic-spectrum disorder and other developmental disorders.
特佈他林穿過胎磐屏障和胎兒的血腦屏障，可能導致自閉症系列障礙和其他精神障礙。

Mercury is a neurotoxin that, when ingested by pregnant women who eat contaminated fish, enters the bloodstream, crosses the placental barrier and impairs fetal brain development, thereby causing mental and physical harms.
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