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Grzegorz Mikusiński Malgorzata Blicharska Hans Antonson Marianne Henningsson Görgen Göransson Per Angelstam 《Landscape Research》2013,38(3):384-393
Implementation of the European Landscape Convention requires new tools that link ecological, social and cultural dimensions in practical planning. Here, we propose connectivity as a conceptual tool to include different dimensions into landscape and spatial planning. We present a short review of the connectivity concept in relation to ecological, social and cultural dimensions and illustrate it by examples from a real landscape planning case. 相似文献
94.
Traumatic Acid Reduces Oxidative Stress and Enhances Collagen Biosynthesis in Cultured Human Skin Fibroblasts 下载免费PDF全文
Traumatic acid (TA) is a plant hormone (cytokinin) that in terms of chemical structure belongs to the group of fatty acids derivatives. It was isolated from Phaseolus vulgaris. TA activity and its influence on human cells and organism has not previously been the subject of research. The aim of this study was to examine the effects of TA on collagen content and basic oxidative stress parameters, such as antioxidative enzyme activity, reduced glutathione, thiol group content, and lipid peroxidation in physiological conditions. The results show a stimulatory effect of TA on tested parameters. TA caused a decrease in membrane phospholipid peroxidation and exhibited protective properties against ROS production. It also increases protein and collagen biosynthesis and its secretion into the culture medium. The present findings reveal that TA exhibits multiple and complex activity in fibroblast cells in vitro. TA, with its activity similar to unsaturated fatty acids, shows antioxidant and stimulatory effects on collagen biosynthesis. It is a potentially powerful agent with applications in the treatment of many skin diseases connected with oxidative stress and collagen biosynthesis disorders. 相似文献
95.
Acrylic bone cements modified with poly(ethylene glycol)‐based biocompatible phase‐change materials 下载免费PDF全文
The high polymerization temperature of acrylic bone cements used in hip replacement implantation may cause thermal necrosis of surrounding tissues. In order to reduce the polymerization temperature, acrylic bone cement has been modified with a biocompatible polymeric phase‐change material (PCM) based on poly(ethylene glycol) (PEG) of different molecular weights and stabilized with potato starch. Structural and morphological studies were performed, and the thermal and mechanical properties were investigated. The incorporation of PEG‐based PCM led to a decrease in the polymerization temperature of bone cement from 70 °C for unmodified cement to 58 °C for modified cement. Modified cement materials were stable in incubation tests, although acoustic analysis data revealed a decrease in propagation speed after incubation, which indicates formation of material defects (pores, cracks, voids, etc.) due to water activity. However, in the regeneration process, these defects can be filled by freshly grown bone tissue leading to better incorporation of bone cement replacements into tissue. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43898. 相似文献
96.
Physicochemical quality and oxidative stability of linseed (Linum usitatissimum) and camelina (Camelina sativa) cold‐pressed oils from retail outlets 下载免费PDF全文
97.
Jadwiga Bucheska 《应用聚合物科学杂志》1996,60(4):519-529
Nuclear magnetic resonance spectroscopy was used to investigate the position of active centers in polyamide fibers subjected to graft copolymerization with poly(acrylic acid), poly(itaconic acid), and poly(2-vinylpyridine) initiated by thermal oxidation in air. As a result, structural changes in polyamide fibers brought about by oxidation and subsequent grafting of the above mentioned polymers were observed. It was estimated that the generation of active centers that initiate the copolymerization take place at the nitrogen atoms of the amide groups in the polyamide chain. This was confirmed by the broadening of the absorption band for the methylone group adjacent to the nitrogen as well as by the absence of a new absorption band for the methine groups, assuming that the generation of active centers and grafting would take place at the carbon atom of the methylene group in position α to the amide group. © 1996 John Wiley & Sons, Inc. 相似文献
98.
I. A. Gritskova N. I. Prokopov V. R. Cherkasov A. A. Ishkov I. Grzywa-Niksiska E. J. Grzywa 《应用聚合物科学杂志》1996,61(9):1465-1471
New methods of preparing polymer suspensions of narrow particle size distribution with amino and carboxylic groups on the particle surface have been suggested. The effects of various factors on the diameter and size distribution of polymer particles, their stability, and concentration of functional groups on the particle surface were investigated. The application of such polymer suspensions for immunochemical studies was shown. © 1996 John Wiley & Sons, Inc. 相似文献
99.
Edyta Wgowska Maria Koziokiewicz Daria Kamiska Bartomiej Grobelski Dariusz Paweczak Marek Koodziejczyk Stanisaw Bielecki Edyta Gendaszewska-Darmach 《International journal of molecular sciences》2022,23(1)
Chronic wound healing is currently a severe problem due to its incidence and associated complications. Intensive research is underway on substances that retain their biological activity in the wound microenvironment and stimulate the formation of new blood vessels critical for tissue regeneration. This group includes synthetic compounds with proangiogenic activity. Previously, we identified phosphorothioate analogs of nucleoside 5′-O-monophosphates as multifunctional ligands of P2Y6 and P2Y14 receptors. The effects of a series of unmodified and phosphorothioate nucleotide analogs on the secretion of VEGF from keratinocytes and fibroblasts, as well as their influence on the viability and proliferation of keratinocytes, fibroblasts, and endothelial cells were analyzed. In addition, the expression profiles of genes encoding nucleotide receptors in tested cell models were also investigated. In this study, we defined thymidine 5′-O-monophosphorothioate (TMPS) as a positive regulator of angiogenesis. Preliminary analyses confirmed the proangiogenic potency of TMPS in vivo. 相似文献