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31.
BACKGROUND/PURPOSE: The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques. METHODS: Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (Corneometer CM 825 and Tewameter TM 210) were analysed before and after a single and 1- and 2-week period of daily application. RESULTS: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle. CONCLUSION: Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin.  相似文献   
32.
目的 探讨肿瘤微血管密度(MVD)与肝细胞性肝癌临床病理及预后的关系。方法对30例肝细胞性肝癌根治性切除病理组织切片进行苏木精伊红染色.并用CD34单克隆抗体进行免疫组化染色,计数被CD34抗体染色的肿瘤血管内皮细胞数,以测定MVD。对MVD与临床病理因素及术后生存率关系进行分析。结果 单因素分析结果表明.MVD水平与肿瘤大小、TNM分期都是影响肝细胞性肝癌预后的因素;多因素分析结果表明.肝癌大小及肿瘤分期是肝细胞性肝癌独立预后因素。结论 MVD是肝细胞性肝癌一种预后因素。  相似文献   
33.
Background/aim: Mid-infrared spectroscopy is a versatile method for in vivo investigation of skin after topical treatment with skin care products.
Methods: FTIR-spectrometer (Bruker Optics) with a flexible silver halide fibre probe (Infrared Fiber Sensors).
Results: Absorbance spectra from 700 to 3000 cm−1 have been recorded to gain information about proteins (amide-I and amide-II vibrations at 1650 and 1550 cm−1), esters (1740 cm−1), carboxylic acid (1710 cm−1), polyalcohols (1050 cm−1) and hydrocarbons (CH n vibrations at 2800–3000 cm−1).
Conclusions: Using the particular light guide, we were able to measure for the first time the effects of lip care products on lips directly. Furthermore, water binding and glycerol content of the skin could be determined simultaneously, as well as the replenishment of lipids by lipid-enriched bath oil.  相似文献   
34.
35.
CT增强扫描在评价NSCLC血管生成中的临床意义   总被引:3,自引:3,他引:0  
目的 探讨非小细胞肺癌 (NSCLC)血管内皮生长因子 (VEGF)的表达水平与CT增强程度的关系 ,从影像学角度评价肿瘤血管生成在肺癌诊断、治疗及淋巴结转移中的临床价值。方法 对 30例NSCLC病人进行动态螺旋CT扫描 (SCT) ,测量病灶增强幅度 ,并利用免疫组化技术检测VEGF。对病灶增强值、VEGF阳性表达及淋巴结转移情况进行统计学分析。结果  30例肺癌病人CT增强值均数为 (36 .2 8± 6 .41 )HU ,VEGF阳性表达 2 1例 ,阴性表达 9例。VEGF在中晚期的阳性表达高于早期病人 (Ρ<0 .0 5) ,淋巴结转移组高于非淋巴结转移组 (Ρ <0 .0 5) ;癌灶增强值与VEGF阳性表达、肿瘤分期及淋巴结转移亦呈正相关。结论 NSCLC的CT增强程度能够反映肿瘤的血管生成 ,并与淋巴结转移密切相关 ,有助于肺癌的诊断、TNM分期 ,而且可以从肿瘤分子生物学行为方面补充目前肺癌分期方法的不足  相似文献   
36.
Abstract Several lines of evidence implicate protein kinase C (PKC) in the development of basal cell and squamous cell carcinomas, tumors which originate from epidermal keratinocytes. To examine PKC in a model relevant to human skin, we exposed normal human epidermal keratinocytes (NHEK) in serum-free media to a variety of PKC agonists and antagonists. NHEK PKC activity increased up to 10-fold within the 1st hour of exposure to tetradecanoyl phorbol acetate (TPA), and gradually returned to control values within 72 h. TPA-induced PKC activity was enhanced by pretreatment of cultures with protein and RNA synthesis inhibitors. TPA-induced growth arrest and differentiation was antagonized by staurosporine. Down-regulation by bryostatin pretreatment blocked TPA-stimulated differentiation. Our overall conclusion is that activation of PKC in cultured human keratinocytes is required for differentiation. These results are crucial to the analysis of compounds suspected of promoting or inhibiting epidermal tumors.  相似文献   
37.
Little is known about whether patients with photosensitive disorders exhibit a different ultraviolet erythema time course from subjects with a normal response to sunlight. We have described the application of an instrument for ambulatory monitoring of the development of ultraviolet erythema by a reflectance method in a group of patients with chronic actinic dermatitis (CAD) and in a group of normal subjects. Investigations of the time course have been reported previously but the techniques used relied upon manual measurement. Consequently sampling frequencies have been considerably lower than the one-minute sample rate used here. We have not demonstrated any difference in the rate at which erythema develops and peaks between patients with CAD and subjects with a normal response to sunlight.  相似文献   
38.
我科自1981年3月至1991年12月应用吻合器行中、下段直肠癌切除术67例,同期发生吻合口漏10例(149%)。本文分析了吻合口漏发生的因素。病变部位、病灶范围、术中操作技术、术前肠道灌洗以及术后骶前引流是影响吻合口漏的重要因素。本文总结了吻合口漏的治疗方法,提倡保守治疗,或加作暂时性横结肠造口术。  相似文献   
39.
40.
A morphometric study of nucleolar organizer regions (NOR) was performed to analyze their distribution, volume, number and shape in the different strata of human normal oral mucosa epithelium and papilloma and in squamous cell carcinoma employing microphotographs of silver-stained paraffin sections. The different NOR-related parameters evidenced significant differences between normal mucosa, papilloma and squamous cell carcinoma. The functional polarity of normal mucosa epithelium and of papilloma is also evidenced in terms of NOR-related parameters. The discriminative value of certain NOR parameters was demonstrated.  相似文献   
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