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1.
The effect of UVB irradiation on the phycobilisomes (PBSs) of Synechococcus sp. PCC 7942 cells was studied. The sucrose density-gradient-isolated PBSs from in vivo UVB-treated (280–320 nm) cells showed a strong decrease in β-phycocyanin (βPC) and -phycocyanin (PC) polypeptides. In addition to a decrease in the linker polypeptides LCM 75 (linker connecting the core to the thylakoid membranes), LR 33 (linker in the rod structure), LRC 31.5 (linker connecting the rod to the core) and LRC 29. In vitro UVB treatment of gradient-isolated intact PBSs for 1 h had no effect on any of the constituent polypeptides, and only after 2 h was a degradation of LCM 75 and LR 33 and a decrease in βPC evident. Further investigation of phycobiliproteins (4 h of UVB irradiation) using polyclonal antibody directed against purified whole PBSs revealed that, in vivo, there was a gradual decline in the levels of LCM 75, LR 33, LRC 31.5, LRC 29, βPC and PC.  相似文献   
2.
Titanium dioxide is a sunscreen pigment with photocatalytic activity. We studied the behavior of different TiO2 specimens used in cosmetic products on the UVB-induced peroxidation of linoleic acid as model substrate and of porcine skin, at different pH values. Lipoperoxidation of linoleic acid occurred to a lower extent with the coated compared to the uncoated TiO2, and it decreased at pH 7.0 compared to 4.0. The addition of organic additives such as propylene glycol and ethanol induced a significant reduction of the lipoperoxidation activity, particularly with the most reactive TiO2 specimens. Similar results were obtained with the porcine skin.  相似文献   
3.
Since ancient times, various herbs have been used in Asia, including Korea, China, and Japan, for wound healing and antiaging of the skin. In this study, we manufactured and chemically analyzed a novel distillate obtained from a fermented mixture of nine anti-inflammatory herbs (Angelica gigas, Lonicera japonica, Dictamnus dasycarpus Turcz., D. opposita Thunb., Ulmus davidiana var. japonica, Hordeum vulgare var. hexastichon Aschers., Xanthium strumarium L., Cnidium officinale, and Houttuynia cordata Thunb.). The fermentation of natural plants possesses beneficial effects in living systems. These activities are attributed to the chemical conversion of the parent plants to functional constituents which show more potent biological activities. In our current study, the distillate has been manufactured after fermenting the nine oriental medical plants with Lactobacillus fermentum, followed by distilling. We analyzed the chemical ingredients involved in the distillate and evaluated the effects of topical application of the distillate on ultraviolet B (UVB)-induced skin damage in Institute of Cancer Research (ICR) mice. Topical application of the distillate significantly ameliorated the macroscopic and microscopic morphology of the dorsal skin against photodamage induced by UVB radiation. Additionally, our current results showed that topical application of the distillate alleviated collagen disruption and reduced levels of proinflammatory cytokines (tumor necrosis factor alpha and interleukin 1 β expressions) in the dorsal skin against UVB radiation. Taken together, our current findings suggest that the distillate has a potential to be used as a material to develop a photoprotective adjuvant.  相似文献   
4.
The extract from Entada phaseoloides was employed as active ingredients of natural origin into cosmetic products, while the components analysis was barely reported. Using LC-DAD-MS/qTOF analysis, eleven compounds (1–11) were proposed or identified from acetone extract of E. phaseoloides leaves (AE). Among them, six phenolic compounds, protocatechuic acid (2), 4-hydroxybenzoic acid (3), luteolin-7-O-β-d-glucoside (5), cirsimaritin (6), dihydrokaempferol (9), and apigenin (10), were isolated by various chromatographic techniques. Protocatechuic acid (2), epicatechin (4), and kaempferol (11) at a concentration 100 μM increased the HaCaT cells viability of the UVB-irradiated cell without any cytotoxicity effect and reduced the expression of COX-2 and iNOS inflammation gene. Moreover, compounds 2 and 4 could have potent effects on cell migration during wound closure. These results suggest that compounds 2, 4, and 11 from AE have anti-photoaging properties and could be employed in pharmaceutical and cosmeceutical products.  相似文献   
5.
Human skin is the largest organ and the most external interface between the environment and the body. Vast communities of viruses, bacteria, archaea, fungi, and mites, collectively named the skin microbiome (SM), cover the skin surface and connected structures. Skin-resident microorganisms contribute to the establishment of cutaneous homeostasis and can modulate host inflammatory responses. Imbalances in the SM structure and function (dysbiosis) are associated with several skin conditions. Therefore, novel target for the skincare field could be represented by strategies, which restore or preserve the SM natural/individual balance. Several of the beneficial effects exerted by the SM are aroused by the microbial metabolite butyrate. Since butyrate exerts a pivotal role in preserving skin health, it could be used as a postbiotic strategy for preventing or treating skin diseases. Herein, we describe and share perspectives of the potential clinical applications of therapeutic strategies using the postbiotic butyrate against human skin diseases.  相似文献   
6.
An automated spectroradiometer for monitoring levels and doses of biologically active UV radiation has been developed. An original design of a double grating zero-dispersion monochromator is proposed. The main characteristics of the design have been tested and it has been shown that as to its parameters the spectroradiometer complies with the recommendations of the World Meteorological Organization for network meters of natural UV radiation. The results of monitoring the spectral distribution and daily doses of the solar UV radiation at the Minsk Ozone Station are presented, and the estimated values of their seasonal variations have been determined.__________Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 2, pp. 264–270, March–April, 2005.  相似文献   
7.
对角质形成细胞HaCaT分别进行中波紫外线(UVB)照射、2,4-二硝基苯磺酸(DNBS)刺激及UVB+DNBS(UD)共同刺激, 利用二维荧光差异胶内凝胶电泳(2D DIGE)、DeCyder定量分析软件和HPLC-nESI-MS/MS分析技术, 对HaCaT细胞产生的差异表达蛋白进行了鉴定. 有65个蛋白质点发生了明显表达差异(P<0.05), 与UVB或DNBS单独处理细胞相比, 有41个蛋白点表现为UVB和DNBS的正协同效应, 13个蛋白点表现为负协同效应, 5个蛋白点与UVB单独处理相近, 6个蛋白点与DNBS单独处理相近. HPLC-nESI-MS/MS从65个差异表达蛋白质点中共鉴定出60种单一(Unique)蛋白. 采用生物信息学方法对这些鉴定蛋白所涉及的分子功能、参与的生物学过程及信号通路进行了系统分析. 实验得到了与紫外辐射和化学诱导损伤的直接相关蛋白, 有助于研究不同环境条件下皮肤癌的形成及皮肤疾病的有效防护与治疗.  相似文献   
8.
联用胶内差异双向电泳(2D-DIGE)和高效液相色谱-电喷雾串联质谱(HPLC-nESI MS/MS)鉴定人角质形成细胞HaCaT应答中波紫外线(UVB)损伤的差异表达蛋白,筛选UVB影响皮肤细胞正常生理功能潜在的靶标蛋白.结果表明:UVB辐射明显影响HaCaT细胞的蛋白质表达谱,DeCyder软件在每块DIGE凝胶上...  相似文献   
9.
研究了中国亚热带地区常见的三种常绿阔叶树种在不同强度的UVB(L-UVB,CK和UVB)作用下,其叶片的叶绿素相对含量及可见光部分的光谱反射率的变化特征。实验结果显示:不同受试树种对UVB敏感不同,叶绿素含量因树种不同变化很大,同一树种在叶绿素含量上过滤UVB处理显著高于加强UVB处理;在可见光部分的光谱反射率,加强UVB的处理则普遍高于L-UVB的处理;树种间对不同胁迫程度的适应存在差异。在不同强度UVB作用后,各树种叶片在可见光部分的光谱反射率的差异主要集中在绿光及红光。本文的研究结果表明亚热带常绿阔叶树种对UVB具有较强的敏感性,不同树种对UVB处理的反应不同。  相似文献   
10.
Characterization of snake skin by thermoanalytical techniques   总被引:1,自引:0,他引:1  
Snake skin is a viable and readily available material as a model for human skin. Pharmaceutical applications use shed snake skin to study the effects of sunscreens on exposure to UV radiation (e.g. benzophenone on Boa integument). In order to understand the effects of radiation or drug transport through this model skin, one must determine its basic physical properties. This preliminary study evaluated two types of snake skin, namely Cuban Boa a 'dark' skin (Epicrates angulifer) and Green tree python a 'light' skin (Morelia viridis). Previous studies by other investigators have used pig, rabbit and snake skin as a human skin substitute. The structure of both snake skins was comparable based on IR spectroscopy and were functionally amino acids and moisture. Photomicrography by light and scanning electron microscopy revealed strong anatomic similarities. Morphologically there were two structures visible, namely a cellular and hinge-fibrous area. The thermal techniques indicated a phase transition at 35-75°C, which is associated with lipid melting. There was an 8 and 12% mass loss for the light skin and dark skin, respectively, which is interpreted, in part, as moisture loss at <100°C. The physical and analytical properties establish a base line that will be used in the future to differentiate various sunscreen types, such as benzophenone and octyl salicylate. Study was also done to determine the effect of an application of a commercially available sunscreen using SEM.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
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