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931.
932.
Greasy hair is a common problem in Europe. The first step in developing anti-grease hair products must be to establish a sensitive protocol for measuring any changes in perceived hair greasiness.
Sensitive clinical trials and in vivo evaluation methods of determining hair greasiness have been developed that show significant differences in the perceived hair greasiness following the use of different shampoos.
Products tested in two clinical trials for efficacy as anti-grease shampoos were an anti-grease shampoo containing 2% 3,4-thiolanediol as the active ingredient, and a baby shampoo based on mild surfactants. The same placebo shampoo based on ether sulphates used in typical European shampoo formulations was used in both tests. A shampoo containing 2% zinc pyrithione was included in the trials as a control, since there were indications that this would increase the amount of hair greasiness.
Neither of the test products were shown to be effective anti-grease shampoos. The shampoo containing 2% zinc pyrithione was shown to produce significantly more greasiness than both the placebo and the test shampoos.
Since significant differences could be shown between the different shampoos, the protocol and in vivo evaluation techniques used in these clinical trials are considered to be validated.
Méthodes in vivo d'évaluation du graissage des cheveux  相似文献   
933.
描述了超声波的生物物理特性——机械按摩作用、温热作用和理化作用。在此基础上,讨论了超声美容的作用机理。文中还对超声美容机的结构和主要电路进行了分析。  相似文献   
934.
Fine details on the surface of human hair   总被引:1,自引:0,他引:1  
Some previously unreported fine variations in the form of normal hairs are described as they are observed in the scanning electron microscope (SEM). They all arise in the course of surface frictional wear and the chipping away of the hair surface scale edges and include remanent surface impressions of cuticle scale edges, 'false' scale edges, granular surface remnants and highly irregular (chevron) scale patterns. Mechanisms are proposed for the way in which each of these different fine features arise.
The paper also contains deliberations on the conditions for operating the SEM consistent with obtaining the best information about the architecture of hair surfaces. The correctness of viewing orientation of scanning electron micrographs is also emphasized to avoid misinterpretation of features on the hair surface.  相似文献   
935.
There are basically four problems to solve in order to produce realistic animated synthetic actors with hair: hair modeling and creation, hair motion, collision detection and hair rendering. This paper describes a complete methodology to solve these basic four problems. We present how hair styles may be designed with our Hair Styler module. Then we survey the animation model and emphasize a method of collision processing. Finally, we explain how hair may be rendered using an extension of a standard ray-tracing program. We also show applications of our synthetic actors with various hair styles and different styles of mustaches and beards.  相似文献   
936.
The percutaneous permeation of two oxidative hair dyes was measured by means of pig skin in a flow-through diffusion cell system entirely constructed from Teflon. Pig skin membranes were prepared by reducing full thickness skin with a dermatome to a more in vivo -like barrier layer and their integrity was checked by measuring the steady-state permeation of tritiated water. Initially, the inter- and intraindividual variability of percutaneous permeation was determined with an aqueous solution of 1-(2'-hydroxyethyl)-amino-3,4-methylenedioxybenzene-hydrochloride, an oxidative hair dye component. In the same way the proper flow rate of elution fluid through the receptor cell was found to be most favourable at 10 ml h-1, the thickness of permeation membranes was fixed at 1 mm, and it was shown that storage of the skin at −20°C for up to 35 days did not change the permeability. The percutaneous permeation of the same hair dye component and of 4-amino-2-hydroxymethylphenol-hydrochloride was determined after application to pig skin membranes under practical conditions of hair dyeing. The in vitro skin permeation was in the same order of magnitude as results from comparable in vivo skin absorption studies in rats.
Perméation percutanée in vitro de colorants d'oxydation pour cheveux  相似文献   
937.
938.
Role of proteins in cosmetics   总被引:1,自引:0,他引:1  
The review critically evaluates the safety and effectiveness of proteins or peptides in cosmetic formulations designed for skin and hair care. Special attention is paid to soluble collagen and the use of this fibrillar protein in combination with detergents.
The authors indicate various misconceptions on the mechanism of the effect of collagen and possible risks if the formulations containing collagen are not used on intact skin. Besides the moisturizing effect of collagen on the stratum corneum, the formation of a protective layer on the surface of the skin or hair, and the formation of complexes with detergents and the mechanisms of the effectiveness of this protein are considered.
Le role des proteines dans les cosmetiques  相似文献   
939.
杭州高校女大学生形体现状及可塑性研究   总被引:2,自引:0,他引:2  
本研究通过对杭州高校女大学生形体现状的调查,结果表明杭州高校女大学生形体发展趋势为“瘦”形体,并且还存在各种身体形态发展不平衡现象,体质指数(BMI)值在1822kg/m2的人数有81.25%,但总体水平低于全国同龄人平均水平。根据女大学生的形体现状,女性青春发育后期的生理特点,提出可塑性建议,防止女大学生形体向不健康方向发展,促使女大学生形成健康科学的形体审美观。  相似文献   
940.
Summary: A novel human hair protein hybrid fiber was developed by combining (i) the high‐efficiency extraction technique for preparing human hair proteins and (ii) the watery hybridization spinning method using gellan and chitosan. The resulting human hair protein‐gellan‐chitosan hybrid fibers are conveniently produced by simply mixing the 7–35 wt.‐% human hair protein‐1.0 wt.‐% gellan aqueous solution and the 1.0 wt.‐% chitosan‐0.15 M acetic acid solution at 50 °C, followed by pulling out to spin the human hair protein‐gellan‐chitosan ternary complex thus formed at the aqueous solution interface. By use of this simple procedure and ambient spinning condition, the human hair proteins were successfully incorporated into the fiber matrix of gellan‐chitosan, without any denaturation and degradation. The hybrid fiber can also be recognized as a new type of the regenerated human hair keratin fiber, because of its high purity and content of human hair keratin types I and II. Mechanical strength of the human hair protein‐gellan‐chitosan fiber varies from 108 to 153 MPa, depending on the contents of the human hair proteins. SEM observation revealed that the incorporated human hair proteins were found as the particles (1–10 μm) on the fiber surface. The type I and II keratins in the fiber matrices were rapidly biodegraded by chymotrypsin within 30 min, and the digested fragments slowly released from the fiber matrices. Thus, the human hair hybrid fiber is a very promising material to have a broad spectrum of applications as the engineering fibers, particularly for the medical uses, because the human hair proteins are easily available, biocompatible, and bioresorbable materials.

Gellan‐chitosan hybrid fiber (a), human hair protein‐gellan‐chitosan hybrid fiber (b).  相似文献   

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