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排序方式: 共有1685条查询结果,搜索用时 15 毫秒
991.
The aim of this work was to evaluate the performance of the fungus Lentinula edodes UEC 2019 in the treatment of an effluent derived from a wood laminate manufacturing process. The factorial design methodology was employed to verify the influence of the source of nitrogen, co-substratum and treatment time variables on the color and total phenols reduction. Assays were conducted in Erlenmeyer flasks and bench bioreactor and the obtained results showed that the best conditions for the effluent remediation were observed when using the effluent itself as the nitrogen source (1g/L) and glucose (79 g/L) as co-substratum (glucose) during a treatment period of 30 days. It was possible the remove 92% phenol, 97% color and reduce the COD in the bioreactor by 99% while controlling the temperature, pH and feeding. These results demonstrate that the fungus was able to use the effluent components as substrate and that it has potential for use in wood lamination effluent remediation. 相似文献
992.
Bruno Vincenzo Fiod Riccio Ana Beatriz Klosowski Eduardo Prestes Taynara Barbosa de Sousa Laís Caroline de Assunção Morais Bruna Mikulis Lemes Flávio Luís Beltrame Patrícia Mazureki Campos Priscileila Colerato Ferrari 《应用聚合物科学杂志》2021,138(21):50468
Bionanocomposite films based on chitosan and nanocellulose (nanocrystals or nanofibrils) have gained considerable attention for biomedical applications, especially for wound dressings. However, the development of these films as controlled drug release dressings is still under-exploited. Therefore, this work aimed to design chitosan/nanocellulose-based bionanocomposite films, loaded by betamethasone or silver sulfadiazine, as functional dressings. The films were obtained by solvent casting and characterized by physicochemical, mechanical, barrier properties, in vitro drug release, and antimicrobial activity. The nanocellulose type, physical state, and content caused influence on the film's properties providing different physical, barrier, and drug release profiles. They are semi-occlusive and mechanically resistant; the drug release is controlled, and possesses antimicrobial activity. In conclusion, the developed biodegradable bionanocomposite films are promising as active dressings for controlled drug delivery in the wound site and have specific applications according to their features to treat inflamed and purulent wounds, non-infectious dry wounds, and infectious wounds. 相似文献
993.
Numerous studies have demonstrated that alterations in membrane composition or fluidity are often associated with alterations
in the properties of membrane-bound enzymes. In order to obtain membranes of varying fluidity, rats were fed diets that were
either fat-free or supplemented with 15% safflower oil, and two properties associated with aorta and liver microsomal membranes
were selected for study: stearyl CoA desaturase activity, and fluidity as monitored by fatty acid composition and microviscosity
(measured by fluorescence depolarization). If fluidity directly modulates desaturase activity, one would predict that a low
fluidity would stimulate the desaturase activity. Ten times more desaturase activity is present in aorta microsomes from rats
on a fat-free diet than in microsomes from rats on a safflower oil supplemented diet. However, on the fat-free diet, these
aorta microsomes were more fluid than those of rats fed safflower oil supplemented diet. The fluidity of liver microsomal
membranes was not altered in response to diet, despite significant changes in desaturase enzyme content. The contrasting evidence
presented here suggests that no correlation exists between desaturase enzyme activity and membrane fluidity in the two tissues
studies. We have demonstrated that the aorta has appreciable capacity to desaturate stearyl CoA and that dietary manipulation
causes significant changes in aorta membrane fluidity that may be of sufficient magnitude to affect the overall metabolism
of aorta cells. 相似文献
994.
Valrie Briard Nadine Leconte Franoise Michel Marie‐Caroline Michalski 《European Journal of Lipid Science and Technology》2003,105(11):677-682
Native milk fat globules of various mean diameters, ranging from d43 = 1.5 to 7.3 μm, were obtained using microfiltration of raw whole milk acquired in winter and spring. After total lipid extraction, fatty acid composition was characterized by methyl and butyl ester analysis using gas chromatography. The oleic and linoleic acid content of milk obtained in winter increased with fat globule size, whereas myristic and palmitic acid decreased. There was significantly more lauric, myristic and palmitoleic acid, and less stearic acid in small fat globules compared to large fat globules in milk obtained in both winter and spring. The relative content of oleic and linoleic acids were found to depend on fat globule size and season. Results are interpreted on the basis of the relative content of milk fat globule membrane depending on fat globule size, and on consequences of compositional variations on milk fat globule melting behavior. 相似文献
995.
996.
Yue Liu Joseph Hubert Galani Yamdeu Yun Yun Gong Caroline Orfila 《Comprehensive Reviews in Food Science and Food Safety》2020,19(4):1521-1560
Contamination of agricultural and food products by some fungi species that produce mycotoxins can result in unsafe food and feed. Mycotoxins have been demonstrated to have disease‐causing activities, including carcinogenicity, immune toxicity, teratogenicity, neurotoxicity, nephrotoxicity, and hepatotoxicity. Most of mycotoxins are heat stable and cannot be easily destroyed by conventional thermal food processing or domestic cooking methods. Postharvest approaches to prevent growth of mycotoxin‐producing fungi and detoxify mycotoxins from contaminated food are important topics in food safety research. Physical, chemical, and biological methods have been applied to prevent fungal growth or mycotoxin production, or to reduce mycotoxin content in the postharvest period and contribute toward mitigating against the effects of mycotoxins on human health. This literature review aims to evaluate postharvest approaches that have been applied to control both fungi growth and mycotoxin content in food and discuss their potential for upscaling to industrial scale. 相似文献
997.
Prof. Dr. Dirk Tischler Eric Gädke Daniel Eggerichs Dr. Alvaro Gomez Baraibar Dr. Carolin Mügge Dr. Anika Scholtissek Dr. Caroline E. Paul 《Chembiochem : a European journal of chemical biology》2020,21(8):1217-1225
Ene-reductases allow regio- and stereoselective reduction of activated C=C double bonds at the expense of nicotinamide adenine dinucleotide cofactors [NAD(P)H]. Biological NAD(P)H can be replaced by synthetic mimics to facilitate enzyme screening and process optimization. The ene-reductase FOYE-1, originating from an acidophilic iron oxidizer, has been described as a promising candidate and is now being explored for applied biocatalysis. Biological and synthetic nicotinamide cofactors were evaluated to fuel FOYE-1 to produce valuable compounds. A maximum activity of (319.7±3.2) U mg−1 with NADPH or of (206.7±3.4) U mg−1 with 1-benzyl-1,4-dihydronicotinamide (BNAH) for the reduction of N-methylmaleimide was observed at 30 °C. Notably, BNAH was found to be a promising reductant but exhibits poor solubility in water. Different organic solvents were therefore assayed: FOYE-1 showed excellent performance in most systems with up to 20 vol% solvent and at temperatures up to 40 °C. Purification and application strategies were evaluated on a small scale to optimize the process. Finally, a 200 mL biotransformation of 750 mg (R)-carvone afforded 495 mg of (2R,5R)-dihydrocarvone (>95 % ee), demonstrating the simplicity of handling and application of FOYE-1. 相似文献
998.
References: 《哈尔滨工业大学学报(英文版)》2007,14(1):23-25
Recent Cryptosporidium outbreaks have highlighted concerns about filter efficiency and in particular particle breakthrough. It is essential to ascertain the causes of Cryptosporidium sized particle breakthrough for Cryptosporidium cannot be destroyed by conventional chlorine disinfection. This research tried to investigate the influence of temperature, flow rate and chemical dosing on particle breakthrough during filtration. The results showed that higher temperatures and coagulant doses could reduce particle breakthrough. The increase of filtration rate made the residual particle counts become larger. There was an optimal dose in filtration and was well correlated to ξ potential. 相似文献
999.
Caroline Merckx Gwenny Cosemans Jana Zschüntzsch Robrecht Raedt Jens Schmidt Boel De Paepe Jan L. De Bleecker 《International journal of molecular sciences》2022,23(6)
Duchenne muscular dystrophy (DMD) is a genetic disorder characterized by progressive muscle degeneration. Osmotic stress participates to DMD pathology and altered levels of osmolyte pathway members have been reported. The goal of this study was to gain insight in osmoregulatory changes in the mdx mouse model by examining the expression of osmolyte pathway members, including taurine transporter (TauT), sodium myo-inositol co-transporter (SMIT), betaine GABA transporter (BGT), and aldose reductase (AR) in the skeletal muscles and diaphragm of mdx mice aged 4, 8, 12, and 26 weeks. Necrosis was most prominent in 12 week-old mdx mice, whereas the amount of regenerated fibers increased until week 26 in the tibialis anterior. TauT protein levels were downregulated in the tibialis anterior and gastrocnemius of 4 to 12 week-old mdx mice, but not in 26 week-old mice, whereas TauT levels in the diaphragm remained significantly lower in 26 week-old mdx mice. In contrast, SMIT protein levels were significantly higher in the muscles of mdx mice when compared to controls. Our study revealed differential regulation of osmolyte pathway members in mdx muscle, which points to their complex involvement in DMD pathogenesis going beyond general osmotic stress responses. These results highlight the potential of osmolyte pathway members as a research interest and future therapeutic target in dystrophinopathy. 相似文献
1000.
Caroline Chapain 《Urban Research & Practice》2020,13(3):300-329
ABSTRACT Cultural/Creative Quarters/Clusters/Districts’ (CCC) have become very popular local development strategies in the last 30 years as reflected within the Urban Planning, Geography, Economics and Cultural Studies literature. However, this multi-disciplinarity has rendered the CCC academic field of research quite fuzzy as authors offers their own definition or borrow from each other without clear explanations. In order to address this issue, this paper presents a systematic literature review and analyses the ways these concepts have evolved, what have been the themes and dimensions associated with them, how they have been studied and researched, and then suggest a renewed research agenda. 相似文献