Tears contain oil, in this YouTube video, the doctor is pointing out the oil glands that are in the eyelid.
眼泪中含有油脂。在这个YouTube视频中,医生所指的部位是眼睑中的油腺。
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In severe cystic acne cases, stronger retinoids actually work at the deeper layers of skin to reduce the size of the oil glands so they produce less sebum.