Tagami H, Kanamaru Y, Inoue K, Suehisa S, Inoue F, Iwatsuki K, Yoshikuni K, Yamada M
J Invest Dermatol. 1982 May;78(5):425-8. doi: 10.1111/1523-1747.ep12507756.
Based on the evidence from our previous studies that we can evaluate the hydration state of the skin surface quickly and quantitatively in terms of conductance to the high frequency electric current of 3.5 MHz, we have established a simple in vivo function test that furnishes information on the hygroscopic property and water-holding capacity of the stratum corneum in a few minutes. The test procedure consists of electromeasurements before and after application of a droplet of water on the skin for 10 seconds to obtain data on the hygroscopic property of the skin surface and later serial measurements at an interval of 30 seconds for 2 min to evaluate the water-holding capacity. Under usual ambient conditions normal skin surface showed a high rise in conductance just after application of water, which was followed by a rapid fall-off within 30 seconds, thereafter by gradual return to the prehydration levels by 2 min. By this method we have demonstrated that (i) the superficial horny layer of normal skin is much less hygroscopic and less capable of holding water than the corresponding deeper portions and that (ii) scaly skin shows functional defects in both hygroscopicity and water-holding capacity, between which the former normalizes much faster than the latter.
基于我们之前研究的证据，即我们可以根据对3.5MHz高频电流的传导率快速定量地评估皮肤表面的水合状态，我们建立了一种简单的体内功能测试，该测试能在几分钟内提供有关角质层吸湿特性和持水能力的信息。测试过程包括在皮肤上滴一滴水10秒前后进行电测量，以获取皮肤表面吸湿特性的数据，随后每隔30秒进行连续测量，持续2分钟，以评估持水能力。在通常的环境条件下，正常皮肤表面在滴水后电导率会迅速升高，随后在30秒内迅速下降，此后在2分钟内逐渐恢复到水化前的水平。通过这种方法我们证明了：（i）正常皮肤的浅表角质层比相应的深层角质层吸湿能力和持水能力都要弱得多；（ii）鳞状皮肤在吸湿能力和持水能力方面都存在功能缺陷，其中前者比后者恢复正常的速度要快得多。
