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排序方式: 共有700条查询结果,搜索用时 218 毫秒
81.
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Huifang Chen Yannan Song Yafang Peng Meifeng Wang Wubliker Dessie Gregory J. Duns Lijian Xu Xiaofang Luo Zuodong Qin 《Macromolecular bioscience》2023,23(4):2200514
Bacterial infections of the wound surface can be painful for patients, and traditional dressings do not effectively address this problem. In this study, an antimicrobial wound dressing is prepared using a novel antimicrobial peptide, HX-12C. This hydrogel system is based on the natural biomaterials sodium alginate and gelatin, utilizing calcium carbonate as a source of Ca2+, and ionic cross-linking is facilitated by lowering the solution pH. The resulting sodium alginate/gelatin HX-12C-loaded hydrogel (CaAGEAM) has good mechanical and adhesion properties, biocompatibility and in vitro degradability. Its extraordinary antibacterial efficacy (>98%) is verified by an antibacterial experiment. More importantly, in vivo experiments further demonstrate its healing-promotion effect, with a 95% wound healing rate by day 9. Tissue staining demonstrates that the hydrogel containing antimicrobial peptides is effective in suppressing inflammation. The dressing promotes wound healing by stimulating the deposition of skin appendages and collagen. The results of this study suggest that composite hydrogels containing antimicrobial peptides are a promising new type of dressing to promote the healing of infected wounds. 相似文献
83.
Variable-weight optical orthogonal codes(OOCs) were introduced by G. C. YANG for multimedia optical CDMA systems with multiple quality of service(Qo S) requirements. In this paper, some infinite classes of optimal cyclic packing are presented. Optimal(24u, {3, 4}, 1,{2/3, 1/3})-OOCs for any positive integer u > 1 are established. 相似文献
84.
Inside Back Cover: Molecular Imaging of Growth,Metabolism, and Antibiotic Inhibition in Bacterial Colonies by Laser Ablation Electrospray Ionization Mass Spectrometry (Angew. Chem. Int. Ed. 48/2016)
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Dr. Hang Li Pranav Balan Prof. Akos Vertes 《Angewandte Chemie (International ed. in English)》2016,55(48):15181-15181
85.
Ferrous Iron Binding Key to Mms6 Magnetite Biomineralisation: A Mechanistic Study to Understand Magnetite Formation Using pH Titration and NMR Spectroscopy
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Dr. Andrea E. Rawlings Dr. Jonathan P. Bramble Andrea M. Hounslow Prof. Michael P. Williamson Dr. Amy E. Monnington Dr. David J. Cooke Dr. Sarah S. Staniland 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(23):7885-7894
Formation of magnetite nanocrystals by magnetotactic bacteria is controlled by specific proteins which regulate the particles’ nucleation and growth. One such protein is Mms6. This small, amphiphilic protein can self‐assemble and bind ferric ions to aid in magnetite formation. To understand the role of Mms6 during in vitro iron oxide precipitation we have performed in situ pH titrations. We find Mms6 has little effect during ferric salt precipitation, but exerts greatest influence during the incorporation of ferrous ions and conversion of this salt to mixed‐valence iron minerals, suggesting Mms6 has a hitherto unrecorded ferrous iron interacting property which promotes the formation of magnetite in ferrous‐rich solutions. We show ferrous binding to the DEEVE motif within the C‐terminal region of Mms6 by NMR spectroscopy, and model these binding events using molecular simulations. We conclude that Mms6 functions as a magnetite nucleating protein under conditions where ferrous ions predominate. 相似文献
86.
为了从微观水平研究细菌生物吸附及转化铅机理,利用原位微区同步辐射X射线荧光(μ-SRXRF)及X射线吸收近边结构谱( XANES)研究云南兰坪铅锌矿区农田土壤样品中筛选的铅耐受性细菌吸附铅的分布特征及铅形态转化规律。土壤中具有铅耐受性的菌株主要为Arthrobacter sp.属(节杆菌属),采用μ-SRXRF对其吸附铅的含量进行快速简单直接分析,部分细菌吸附铅的含量高达5925μg/g,富集系数达14.8。XANES结果表明,细菌吸附 Pb 后存在形态为 PbS、(C17 H35 COO)2Pb 和 Pb5(PO4)3Cl 分别占58.0%,22.2%和19.8%,与培养基本身以有机态为主的Pb形态有明显差异,表明培养基中铅被细菌吸附后有向硫化物转化的趋势,这为研究重金属生物有效性的影响因素提供了实验参考。 相似文献
87.
Corrigendum: Muropeptides in Pseudomonas aeruginosa and their Role as Elicitors of β‐Lactam‐Antibiotic Resistance
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88.
Pakorn Wattana-Amorn Waranya Charoenwongsa Christopher Williams Matthew P. Crump 《Natural product research》2016,30(17):1980-1983
Two bioactive cyclic dipeptides, cyclo(L-Pro-L-Tyr) and cyclo(D-Pro-L-Tyr), were isolated from the culture broth of Streptomyces sp. strain 22-4 and tested against three economically important plant pathogens, Xanthomonas axonopodis pv. citri, Ralstonia solanacearum and Clavibacter michiganensis. Both cyclic dipeptides were active against X. axonopodis pv. citri and R. Solanacearum with MIC of 31.25 μg/mL. No activity could be observed against C. michiganensis. 相似文献
89.
90.