Wohlrab W
Dermatologica. 1977;155(2):97-107.
Long-term application up to 8 weeks of a 10% urea solution provokes an epidermal thinning expressed in a decreased number of DNA-synthetizing cells. This epidermal reaction cannot be established after topical use of HTH emulsion. Even by daily application during 8 weeks no change was seen. The absence of epidermal thinning after HTH exposure can be explained as an additive effect of urea and the other constituents of the HTH emulsion. This opinion is supported by the results after application of urea together with Tween 60 in that the acanthogenic effect of Tween 60 is decreased by addition of urea. On the other side, the therapeutic efficiency of 10% 5-fluorouracil solution can be increased remarkably by preliminary treatment with HTH emulsion. These findings could reach importance in the topical therapy with regard to the possibility to improve the effectiveness of any drug by addition of, or preliminary treatment with, urea.
长期应用10%尿素溶液达8周会引发表皮变薄，表现为DNA合成细胞数量减少。局部使用HTH乳液后不会出现这种表皮反应。即使连续8周每日使用，也未见变化。HTH暴露后未出现表皮变薄可解释为尿素与HTH乳液其他成分的相加作用。尿素与吐温60一起应用后的结果支持了这一观点，即添加尿素会降低吐温60的促棘层肥厚作用。另一方面，10%氟尿嘧啶溶液的治疗效果可通过HTH乳液预处理显著提高。这些发现对于局部治疗可能具有重要意义，因为通过添加尿素或用尿素进行预处理有可能提高任何药物的疗效。
