They have successfully inoculated mice against flu using scores of tiny needles that might be referred to as “hyperdermic”, because they do not fully penetrate the skin.

他们成功地用大量的小针头为老鼠做抗流感的预防注射——可以认为是“皮内注射”，因为他们没有完全穿透皮肤。

youdao

The variation from pink to brown not only helps to prevent sunburn but also allows appropriate amounts of sunlight to penetrate the skin to create the vitamin D3 from its inactive precursors.

从粉色到棕色的变化不仅帮助防止了晒伤，而且还让合适数量的阳光穿透皮肤从而把未激活的前体变成维生素d3。

youdao

Thousands of microscopic holes in the mesh fabric allow 80 per cent of sunlight to penetrate through to the skin.

泳衣的网状布料上有数千个微孔，可以使80%的阳光穿透泳衣直射皮肤。

youdao

It is unclear whether the antioxidants in grapeseed oil penetrate the skin sufficiently to benefit the skin, dermatologists say.

WSJ: An Oil's Promises, From Cooking to Cosmetics

The recording electrodes can be carried by a skull cap, and nothing has to penetrate the skin.

ECONOMIST: Bionics (I)

And so -- but apparently the ones that are being tested right now by all the big laboratories, they only can be used for skin cancer or places where the light can penetrate fairly close to the surface.

WHITEHOUSE: Backyard Discussion on Women and the Economy