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capillary; capillary vessel
指先の毛細血管を観察する。
Observe the capillaries at the fingertips.
赤みは毛細血管の拡張が原因です。
The redness is caused by the dilation of capillaries.
血液は毛細血管を通り全身へ運ばれる。
Blood is carried throughout the body via capillaries.