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视频排行

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首播

重播

  脐带——连接胎儿与母亲的纽带

  脐带是连接胎儿与母亲的纽带,是胎儿生命的桥梁。它一端连接于胎儿脐轮,另一端连接于胎盘。脐带中有两跟脐动脉和一条脐静脉,以及包裹于它们表面的胶冻状组织——华尔通氏胶所组成。

  通过脐带,胎儿从母亲获得氧气以及所需的各种营养物质,排出胎儿体内的废物。正常情况下,脐带的长度约为50厘米,长于70厘米为脐带过长,短于30厘米为脐带过短。

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