神经酰胺 NS × 防晒

口服类胡萝卜素增加皮肤类胡萝卜素和自由基清除活性，但ceramide NS仅作为皮肤脂质中显著增加的一项，并非直接测试ceramide NS的防晒功效，且防晒效果归因于类胡萝卜素而非ceramide NS。

Oral carotenoids increase skin carotenoids and radical scavenging activity, but ceramide NS is only one of the significantly increased skin lipids, not directly testing the sun protection efficacy of ceramide NS, and the sun protection effect is attributed to carotenoids rather than ceramide NS.

糖原促进角质形成细胞中ceramide NS的产生，但未测试防晒功效。

Glycogen promotes ceramide NS production in keratinocytes, but does not test sun protection efficacy.

模拟显示类胡萝卜素影响含ceramide NS的脂质双层结构，但未直接测试ceramide NS的防晒功效。

Simulation shows carotenoids affect the structure of lipid bilayers containing ceramide NS, but does not directly test the sun protection efficacy of ceramide NS.

仅涉及ceramide NS的微生物合成，未涉及防晒功效。

Only involves microbial synthesis of ceramide NS, not related to sun protection efficacy.

模拟显示ceramide NS膜的水渗透性高于ceramide NP，表明ceramide NS不利于屏障功能，与防晒（屏障功能）相悖。

Simulation shows water permeability of ceramide NS membrane is higher than ceramide NP, indicating ceramide NS is detrimental to barrier function, contrary to sun protection (barrier function).