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Skin ageing is accompanied by wrinkle formation. In particular, periorbital wrinkle formation is a relatively early sign of skin ageing. We evaluated the effects of a preparation containing asiaticoside on the periorbital wrinkles of a group of volunteers. The effectiveness of the active compound, asiaticoside, in a base-cream preparation for the treatment of temporal periorbital wrinkles was tested on 27 female volunteers as follows: the women applied the cream twice a day to the region of interest for 12 weeks. Same women also applied a vehicle control cream to the periorbital skin around the other eye. Negative replicas were taken of the periorbital skin before treatment and 4, 8, and 12 weeks after application of the cream. The results were evaluated by semi-automated morphometry of the plastic replicas. After 12 weeks of treatment, there was a significant improvement of the periorbital wrinkles in majority of the volunteers who tested the cream. Of the 27 women examined with periocular wrinkles, 65% showed an improvement at the end of the treatment. In three cases, the improvement was 100% (disappearance of the crow's feet), 75% +/- 1.97 and 79% +/- 2.82. On six eyes, there was no significant change after the treatment. With 12 weeks of treatment with the asiaticoside-containing cream, most of the periorbital wrinkles were attenuated to some degree, and some women experienced a significant improvement of the periorbital wrinkles on one of their eyes.  相似文献   

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Ethnic and genetic differences modify skin structure and function. Skin photoageing is becoming one of the most studied cosmetological topics. However, there are relatively few data available to evaluate the effect of ethnic skin origin on the degree of photoageing, particularly among people inhabiting sunny and hot climate as in South Asia. Two hundred and forty participants, enrolled in the study conducted in Pokhara valley, Nepal, were classified into four different age categories viz. below 30, 30-50, 50-60 and above 60 years. Participants answered the questioner regarding their age, gender, ethnic origin, occupation, skin characteristics, lifestyle factors, type of cosmetic and skin care products used, drug treatment and personal skin condition evaluation. Skin hyperpigmentation and the degree of wrinkling, the two most important parameters related to photoageing, were particularly evaluated in two ethnic groups, namely Aryan-origin and Mongolian-origin participants. The study showed that Aryan-origin ethnic skin was more wrinkled and darker than that of Mongolian. Male skin was found to be darker than the female skin, which might be the result of the use of sun-protective cosmetic products among women. Smoking was found to increase the degree of wrinkling; however, no differences related to ethnic origin in relation to smoking were observed. This study indicates the need to further evaluate the differences in skin response to daily exposure to strong sun among various ethnic-origin inhabitants.  相似文献   

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为改善鱼鳞明胶膜的性能,测定添加明胶质量的0%、25%、50%、75%、100%桔子精油的可食膜的厚度、机械性能、水溶性、水蒸汽透过率、色泽、透明度和透光率、热性能、红外光谱和抑菌活性。结果表明:随着精油浓度的增加,鱼鳞明胶膜的厚度、断裂伸长率增加,拉伸强度、透光率、水溶性降低,水蒸汽透过率呈现先增加后降低的趋势;差示扫描量热法(DSC)和傅里叶变换红外光谱(FTIR)分析结果表明,鱼鳞明胶分子与桔子精油的部分成分发生相互作用,在一定程度上改善了明胶膜的热稳定性;桔子精油的添加还赋予了鱼鳞明胶膜抑菌作用。综合评价得出75%质量浓度的桔子精油添加量对鱼鳞明胶膜各项性能优化效果最好,本实验结果可为生产高性能的鱼鳞明胶膜提供理论基础。  相似文献   

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采用EGCG单体对斑点叉尾鮰鱼皮胶原薄片进行改性。从斑点叉尾鮰鱼皮中提取了胶原之后,利用EGCG分别对胶原薄片和胶原溶液进行了交联。然后利用DSC、FITR、X-RAY和SEM分析了胶原薄片改性前后的性质变化,并与戊二醛改性的胶原薄片进行了对比。结果表明,胶原薄片先成型再利于EGCG改性,EGCG浓度为0.075%时,使胶原薄片的玻璃态转化温度从194℃提高到207℃,并将胶原晶面间距离从12.6373nm减小到11.9422nm,大幅度拉近了肽链之间的距离,使肽链间连接更紧密。对比未改性胶原薄片,EGCG改性样品截面紧密多空。本研究表明,EGCG可以用于胶原改性。本研究为活性天然产物用于胶原改性提供了有用信息。   相似文献   

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The face is composed of complicated anatomical components, presenting unique portions, such as the eyes, nose and mouth in a relatively narrow area. Moreover, the facial skin is densely populated by the pilosebaceous units and sweat glands, and its stratum corneum (SC) is much thinner than that of the trunk and limbs, although it is always exposed to the environment. Among various portions of the facial skin, some are more easily irritated than others by environmental stimuli, or are more often affected by certain dermatoses. However, the functional aspects of the different portions of the facial skin have not been studied in detail under a strictly controlled environment in sufficiently large numbers of subjects covering different age groups. Thus, we conducted studies in winter with various biophysical techniques, such as transepidermal water loss (TEWL), as a parameter for SC barrier function, high-frequency conductance as that for skin surface hydration state, skin surface lipids, pH, blood flow and skin surface temperature on the forehead, mid-portion of the cheek (cheek in short), nasal tip (nose in short), nasolabial fold and chin of 20 healthy Japanese females aged 22-37 years (average 25 years) in a climate chamber adjusted to 21 degrees C and 50% relative humidity. Thereafter, we studied the influence of ageing on these biophysical parameters by collecting data of TEWL, high-frequency conductance and size of superficial corneocytes on the cheek, nasolabial fold and chin of 303 healthy Japanese female volunteers of different ages. The obtained results showed that the barrier function of the SC was best on the cheek, presenting the lowest TEWL, which was significantly higher on the nasolabial fold and chin than on the cheek. TEWL showed a decrease with age. In contrast, skin hydration state was higher on the nose, but it tended to be lower on the nasolabial fold, showing a mild age-related increase. The corneocytes on the nasolabial fold and chin were smaller than those on the cheek. They revealed a clear increase in size with age. Skin surface lipids were richest on the nose, whereas the superficial pH on the nose was the lowest among the regions tested. The skin temperature was lowest on the cheek than on other areas of the face; although, together with the nose, its blood flow was higher than that of the others. These data indicate great regional differences observable in SC functions on the face. In general, the SC barrier function increases with age, probably because of a decreased epidermal turnover rate as recognized by the increase in corneocyte size. Among the various sites, the skin of the nasolabial fold and chin, whose SC consisted of the smallest corneocytes, showed poorest SC properties in barrier function, suggesting the presence of mild invisible inflammation. It is understandable that this area easily develops not only the complaint of sensitive skin to cosmetics but also dermatitis because of various external agents.  相似文献   

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近年来,鱼皮胶原蛋白及其活性肽的研究越来越多。不同提取法得到的胶原蛋白的功能性质具有较大差异,而胶原蛋白的功能性质与其结构紧密相关。本文比较了几种主要的胶原蛋白提取方法,探讨了胶原蛋白结构的研究进展,较详细的阐述了鱼皮胶原蛋白、胶原活性肽的应用及其研究前景。   相似文献   

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赫哲族鱼皮服饰是我国少数民族服饰中最为典型的民族服饰之一,它是赫哲人在历史与与自然长期的互动中,形成独特的民族产物。本文通过总结赫哲族鱼皮服饰的保护现状,以赫哲族独特的生活方式、民族信仰以及特定的地域文化入手,结合鱼皮服饰的材料、色彩、纹样等元素,探索出赫哲族传统服饰与现代服饰的融合创新之路,并对赫哲族鱼皮元素如何在当今服饰中应用提出自己的见解,将赫哲民族文化传承与保护推进到新的高度。  相似文献   

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The rheological and functional properties of gelatin from the skin of bigeye snapper (Priacanthus hamrur) fish were assessed. The protein content of dried gelatin was 94.6% and moisture content was 4.2%. The amino acid profile of gelatin revealed high proportion of glycine and imino acids. The bloom strength of solidified gelatin was 108 g. The average molecular weight of fish skin gelatin was 282 kDa as determined by gel filtration technique. The emulsion capacity (EC) of gelatin at a concentration of 0.05% (w/v) was 1.91 ml oil/mg protein and with increase in concentration, the EC values decreased. The gelling and melting temperatures of gelatin were 10 and 16.8 °C, respectively as obtained by small deformation measurements. The flow behavior of gelatin solution as a function of concentration and temperature revealed non-Newtonian behavior with pseudoplastic phenomenon. The Casson and Herschel–Bulkley models were suitable to study the flow behavior. The yield stress was maximum at 10 °C with the concentration of 30 mg/ml. Thermal gelation behavior of threadfin bream (Nemipterus japonicus) mince in presence of different concentration of gelatin was assessed. Gelatin at a concentration of 0.5% yielded higher storage modulus (G′) value than control. Frequency sweep of heat set gel with gelatin revealed strong network formation.  相似文献   

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刘洋  夏俪宁  贾慧  李琦  潘锦锋 《食品科学》2018,39(7):236-242
明胶提取温度和甘油质量浓度是影响明胶膜性质的基本因素。本研究以马哈鱼(Oncorhynchus keta) 鱼皮为原料,采用不同温度(40、50、60、70、80、90 ℃)提取明胶,考察不同甘油质量浓度(1.1、1.2、 1.5 g/100 mL)下明胶膜的厚度、机械性能、光学性质、微观结构和红外特性。研究发现,40、50、60 ℃明胶 膜的厚度高于70、80、90 ℃明胶膜的厚度(P<0.05)。50、60 ℃膜的拉伸强度(tensile strength,TS)高于 70、80、90 ℃膜的(P<0.05);添加1.5 g/100 mL甘油,膜的断裂伸长率随提取温度升高而上升(P<0.05); 50、70、80 ℃膜的TS随甘油质量浓度升高而下降(P<0.05)。色差分析表明,膜的a*值随提取温度升高而上升 (P<0.05)。水蒸气透过率随提取温度和甘油质量浓度的升高而升高(P<0.05)。明胶膜于200、280 nm波长处 的透光率为0.00%,350~800 nm范围内的透光率为46.53%~74.57%,60 ℃膜的透光率低于40、50 ℃膜的透光率 (P<0.05)。衰减全反射傅里叶变换红外光谱分析表明膜的图谱呈现典型酰胺A、B、Ⅰ、Ⅱ、Ⅲ带,酰胺A带随 提取温度的升高向低波数移动,且振幅随甘油质量浓度升高而增加。扫描电子显微镜结果显示,膜的截面和表面未 呈现明显断裂或空隙。以上结果表明,温度对马哈鱼鱼皮明胶膜的机械性能、透水性、颜色、透光率影响显著,甘 油质量浓度仅对前二者影响显著,可通过优化提取温度与甘油质量浓度改善马哈鱼鱼皮明胶膜性质。  相似文献   

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Fish gelatins extracted from shark ( Isurus oxyrinchus ) cartilage were dried by three different methods: freeze drying, hot-air drying and spray drying; and their functional properties were investigated. Freeze-dried gelatin was found to have the strongest gel strength, while gelatins made at high temperatures formed weaker gels. The 135-kPa gel strength of freeze-dried gelatin was relatively high. While foam formation ability of the freeze-dried gelatin was the highest, its foam stability was the lowest. In addition, spray-dried gelatin had the best emulsion capacities. Dynamic viscoelastic properties of shark cartilage gelatins prepared by these drying methods were closely correlated with their gel strength. Elasticity modulus ( G '; Pa) and loss modulus ( G "; Pa) of the freeze-dried gelatin had higher values than those prepared by hot-air drying and spray drying; viscoelastic properties of the freeze-dried gelatin were maintained longer than those of other drying methods.  相似文献   

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腌制是鱼类保藏的主要加工手段之一,相比冻藏对设备的要求更低,且能产生独特的腌腊风味,市场前景广阔.腌制过程中,鱼类在微生物、内源酶及盐的作用下,其风味及理化性质会产生较大变化,阐明这种变化规律可以为调控及提高产品品质、指导企业生产、规范市场经营提供理论基础.为此,该文介绍了鱼体挥发性及非挥发性风味化合物,以及部分理化指...  相似文献   

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The objective of this study was to evaluate the effects of microwave processing technology (MPT, 240–800 W, 1 and 4 min) on the functional and structural properties of fish gelatin (FG). It showed that MPT could increase gel strength and texture properties of FG, especially for 240 W. MPT greatly increased emulsifying activity index (EAI) of FG, but decreased its emulsion stability index (ESI). Rheology results showed that MPT increased viscosity of FG, but decreased gelation times. Intrinsic fluorescence and Fourier transform infrared (FTIR) spectroscopy results indicated that MPT could unfold gelatin, contributing to the formation of H-bonds. Scanning electron microscopy (SEM) analysis revealed that low power and short time of MPT-treated gelatin gels had much more dense and less voids. This work provided guidance for the applications of MPT to improve the functional properties of FG, and the results show that MPT-treated FG can replace mammalian gelatin and meet the religious requirement.  相似文献   

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The aquaculture industry has undergone a rapid and continuous growth during the last decade due to increased demands in seafood consumption and reduced pelagic fish production. The aquaculture sector can provide products with a consistent flow and quality standards to cover the market's needs. The modified atmosphere packaging (MAP) technique has evolved over the last two decades and many reports indicate its beneficial effect on many quality parameters during fish and shellfish preservation. The use of MAP can clearly offer an advantage to the safer distribution of quality aquacultured fishery products. This article summarizes most of the experimental data of packaging techniques applied (MAP, VP, various pretreatments and packaging materials) on aquacultured fish and fish products to provide a clear view of the potential for a future commercial use.  相似文献   

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以冰冻鱼皮为原料,制备鱼胶原蛋白粉,其主要工艺包括切碎、去除非胶原蛋白、提取、均质、浓缩、酶解、干燥等过程,并进行了人体试食的安全性与功能性研究。选取30~50岁女性自愿受试者,分为对照组与实验组,对照组50人,受试组51人。实验采用双盲法,受试组与对照组均按3g/d服用鱼胶原蛋白粉或者安慰剂,连续40d,进行了一般性安全性与皮肤水分调节的功能性观察。结果发现,试食组和对照组组间对照、试食组食用前后自身对照皮肤水分有显著差异(p<0.05),具有显著的改善皮肤水分作用。体重、血压、心率、尿常规、大便常规、血常规及生化指标未见明显异常变化,未观察到明显过敏及其它不良反应,说明服用鱼胶原蛋白粉是安全有效的。  相似文献   

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A microwave fat: water content meter designed for use on pelagic fish has been found to exhibit seasonal changes in calibration. This has been examined in detail for sprats ( Sprattus sprattus ) and herring ( Clupea harengus ) and is ascribed in part to the seasonal changes in these species of the protein content, which influences the rotational mobility of water in the tissue. Various solutions to the problems are proposed.  相似文献   

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With the advancement of skin research, today's consumer has increased access to technological information about ageing skin and hair care products. As a result, there is a rapidly increasing demand for proof of efficacy of these products. Recognizing these demands has led to the development and validation of many clinical methods to measure and quantify ageing skin and the effects of anti-ageing treatments. Many of the current testing methods used to research and evaluate anti-ageing product claim to employ sophisticated instruments alongside more traditional clinical methods. Intelligent use of combined clinical methods has enabled the development of technologically advanced consumer products providing enhanced efficacy and performance. Of non-invasive methods for the assessment and quantification of ageing skin, there is a plethora of tools available to the clinical researcher as defined by key clinically observed ageing parameters: skin roughness and surface texture; fine lines and wrinkles; skin pigmentation; skin colour; firmness and elasticity; hair loss; and proliferative lesions. Furthermore, many clinical procedures for the evaluation of ageing skin treatments are combined with invasive procedures, which enable added-value to claims (such as identification and alteration of biochemical markers), particularly in those cases where perception of product effect needs additional support. As discussed herein, clinical methods used in the assessment of skin ageing are many and require a disciplined approach to their use in such investigations.  相似文献   

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