Two muscles, the infraspinatus and teres minor, connect the shoulder blade to the upper arm bone and roll the arms outward.

冈下肌和小圆肌这两块肌肉，将肩胛骨和上臂连接起来，使手臂外旋。

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Primate arms have one long bone, the humerus, in the upper arm above the elbow, and two thinner bones, the radius and ulna, in the forearm.

灵长类的上臂有一根长骨（肱骨），前臂有两根细骨（尺骨和桡骨）。

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Brachium: the part of the upper arm or forelimb extending from the shoulder to the elbow.

肱，上臂：从肩至肘之间的上臂部分或前肢。

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When implanted in the upper arm, it releases the drug over a period of three months to a year.

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The rotator cuff, a group of tendons and muscles connecting the upper arm to the shoulder blade, is also important to paddling.

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These shots, which are still used today, are much safer and more effective than the old-fashioned rabies shots, and are delivered into the upper arm or thigh.

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