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- Abnormalities of the heart's natural pacemaker or of the nerves that conduct its impulses cause arrhythmias. 心脏自然节律点或是引导其脉动的神经的异常会造成心律不整。
- An artificial pacemaker works by restoring the function of a faulty sinoatrial node, the heart's natural pacemaker. 人工心率调整器的作用是使紊乱的心脏天然心率调整器窦房结恢复正常功能。
- The signals that make the heart's muscle fibres contract come from the sinoatrial node, which is the natural pacemaker of the heart. 驱使心脏肌肉纤维收缩的信号来自于窦房结，它是心脏天然的起搏器。
- Electrical signals from a natural pacemaker cause the heart muscle to contract. Valves in the heart keep Blood flowing in one direction. Their snapping shut after each contraction causes the sounds heard as the heartbeat. 从自然心律调节器产生的电子信号导致心脏肌肉收缩。心脏里的瓣膜使血液往同一方向流动,每次收缩后,它们的闭合产生了听起来像是心跳的声音。
- The Branched fibres of cardiac muscle give it a netlike structure; contraction originates in the heart's muscle tissue itself with a signal from the natural pacemaker; vagus and sympathetic nerves control heart rate. 心肌树枝状的纤维就像网状结构;收缩是源自于心脏肌肉组织本身,由天然的节律点产生讯号;迷走神经与交感神经控制心脏的跳动速率。
- It is natural for a cat to catch mice. 猫捉老鼠是本能。
- It's natural to slack2 off towards the end of a hard day's work. 一天紧张工作快结束的时候有些放松是自然的。
- Many natural materials are becoming scarce. 许多天然原料越来越少。
- Our motherland flows with natural resources. 我们祖国蕴藏着丰富的天然资源。
- Events took their natural course. 事态依自然进程发展。
- She has a natural wave in her hair. 她的头发自然卷曲。
- Magnetism is a natural phenomenon. 磁力是一种自然现象。
- It is difficult to be natural when one is tense. 人在紧张的时候很难泰然自若。
- The egoism of an artist sometimes seem natural. 艺术家的自负有时看起来是自然的。
- They used only natural pigments to dye the wool. 他们只用天然颜料染毛织品。
- Children are natural exhibitionists. 儿童天生喜欢自我表现。
- Everything we used was made from natural materials. 我们所用的一切都是由天然材料做成的。
- It's quite natural that you should succeed. 你的成功是很自然的事情。
- He's a natural for the role of Lear. 他是李尔王这一角色的理想人选。
- Most first-class footballers are natural athletes. 多数一流的足球运动员都是天生的健将。
