Structures and biogenetic analysis of lipofuscin bis-retinoids     

Ya-lin WU  Jie LI  Ke YAO 《Journal of Zhejiang University. Science. B》2013,14(9):763-773

Age-related macular degeneration (AMD) is still an incurable blinding eye disease because of complex pathogenic mechanisms and unusual diseased regions.With the use of chemical biology tools,great progress has been achieved in improving the understanding of AMD pathogenesis.The severity of AMD is,at least in part,linked to the non-degradable lipofuscin bis-retinoids in retinal pigment epithelial (RPE).This material is thought to result from the lifelong accumulation of lysosomal residual bodies containing the end products derived from the daily phagocytosis of rod outer segments by RPE cells.Here,we present previously recognized bis-retinoids with focus on structures and biosynthetic pathways.In addition to a brief discussion on the mutual conversion relationships of bis-retinoids,future perspectives and the medical relevance of such studies on these lipofuscin constituents are also highlighted.  相似文献   

Adsorption of methylene blue onto activated carbon produced from tea (Camellia sinensis L.) seed shells: kinetics, equilibrium, and thermodynamics studies     

Jun-jie Gao  Ye-bo Qin  Tao Zhou  Dong-dong Cao  Ping Xu  Danielle Hochstetter  Yue-fei Wang 《Journal of Zhejiang University. Science. B》2013,14(7):650-658

Tea (Camellia sinensis L.) seed shells, the main byproduct of the manufacture of tea seed oil, were used as precursors for the preparation of tea activated carbon (TAC) in the present study. A high yield (44.1%) of TAC was obtained from tea seed shells via a one-step chemical method using ZnCl₂ as an agent. The Brunauer-Emmett-Teller (BET) surface area and the total pore volumes of the obtained TAC were found to be 1 530.67 mg²/g and 0.782 6 cm³/g, respectively. The equilibrium adsorption results were complied with Langmuir isotherm model and its maximum monolayer adsorption capacity was 324.7 mg/g for methylene blue. Adsorption kinetics studies indicated that the pseudo-second-order model yielded the best fit for the kinetic data. An intraparticle diffusion model suggested that the intraparticle diffusion was not the only rate-controlling step. Thermodynamics studies revealed the spontaneous and exothermic nature of the sorption process. These results indicate that tea seed shells could be utilized as a renewable resource to develop activated carbon which is a potential adsorbent for methylene blue.  相似文献   

Copper trihydroxychlorides as pigments in China     

《文物保护研究》2013,58(2):106-111

  相似文献   

股票投资的又一个技术分析法   总被引：1，自引：0，他引：1  

陈文略  李亚兰 《黄冈师范学院学报》2000,20(6):8-11

当投资者进行股票投资且所选股票为蓝筹股时,给出一个最优选取的数学模型。  相似文献   

荷兰菊色素提取工艺研究     

林敏  吴冬青 《湖州师范学院学报》2003,25(3):59-61

以荷兰菊花为原料，通过单因子及正交试验对荷兰菊花色素的提取工艺作了研究，确定了提取的最佳溶剂及最佳工艺条件。  相似文献   

中国山水画漫议     

郑芳 《周口师范学院学报》2001,18(4):90-91

首先提出了为什么要学习山水画.其次,从各个不同的朝代分析了中国山水画的发展过程.希望在继承传统绘画的同时,要弃其糟粕,取其精华.  相似文献   

Copper(II) hydroxide on artefacts: Corrosion,conservation, colourants     

Britta Schmutzler  Gerhard Eggert  Charlotte F. Kuhn-Wawrzinek 《文物保护研究》2017,62(2):61-67

Copper(II) hydroxide (as the rarely occurring mineral spertiniite) is formed under alkaline, oxidising conditions. It has been observed as a naturally occurring corrosion product of brass in sea water. But most occurrences on copper alloys are due to conservation treatments using basic solutions (sodium hydroxide or ammonia) or to intentional patination. Classical brass centrepieces (c. 1800), ‘cleaned’ with ammonia solution, developed a blue spertiniite patina in gaps, where evaporation was hindered. Additional to the danger of stress corrosion cracking this is another reason now outlawing this treatment. Copper pigment layers will transform to copper hydroxide when exposed to bases. The treatment of basic copper salts with bases has been used intentionally in the production of Bremen blue and similar pigments which can be composed of copper hydroxide as well.  相似文献   

国外花色素苷的研究现状与进展   总被引：7，自引：0，他引：7  

丁锐 《陕西理工学院学报(社会科学版)》2004,22(6):73-78

综述了近年来国外学者及研究人员在植物花色素苷的产生、化学成分、结构特征、合成途径、物化性质、药理作用和工业应用等方面的工作与进展.  相似文献   

蛋白质凝胶电泳及染色方法的几点改进     

陈芳  陈久存 《安康学院学报》2007,19(4):78-80

SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)及染色技术,是常用测定蛋白质亚基分子量的方法之一,具有设备简单、操作方便和分辨率高等优点.但在操作中,尤其样品较多时,此方法仍然有一些不足之处.通过大量实践,做以下改进:建立根据不同相对分子量的蛋白质快速选择凝胶浓度的方法,并确立解决蛋白质凝胶电泳和染色过程中的常见问题及改进策略.  相似文献   

Re-Discovering a Roman Wall Painting at Harvard: New Research on a Fragment from the Villa at Boscotrecase     

Elizabeth M. Molacek  Katherine Eremin  Lucy J. Cooper  Georgina Rayner 《文物保护研究》2020,65(5):296-311

ABSTRACT

This article presents historical and scientific analysis, as well as the conservation treatment of a newly rediscovered Roman wall painting fragment, now in the collection of the Harvard Art Museums. Although the piece has not previously been published, it was among a group of fragments removed from a Roman villa near Boscotrecase in southern Italy, an area that has been key to the study of Roman wall painting and other decoration. Technical imaging confirms the use of painting techniques consistent with other high-quality paintings in the area. Materials analysis revealed a palette consistent with published findings of Roman wall paintings, including abundant use of Egyptian blue and green earth. Of interest was the use of Egyptian blue as an optical brightener in select white passages. Despite the high quality of the painting, no cinnabar was present, and all red passages were achieved using hematite. Multiple different white minerals were identified including calcite, aragonite, and gypsum. The widespread presence of gypsum is unusual and may point to alteration.  相似文献