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排序方式: 共有133条查询结果,搜索用时 31 毫秒
61.
Lalas S Gortzi O Athanasiadis V Tsaknis J Chinou I 《Molecules (Basel, Switzerland)》2012,17(3):2330-2334
The antimicrobial activity of the oil extracted with n-hexane from the seeds of Moringa peregrina was tested against Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Candida albicans, C. tropicalis and C. glabrata. The oil proved effective against all of the tested microorganisms. Standard antibiotics (netilmycin, 5-flucytocine, intraconazole and 7-amino-4-methylcoumarin-3-acetic acid) were used for comparison. The resistance to oxidation of the extracted seed oil was also determined. 相似文献
62.
Nicos Maglaveras Ioanna Chouvarda Vassilis G Koutkias George Gogou Irini Lekka Dimitrios Goulis Avram Avramidis Charalambos Karvounis George Louridas E Andrew Balas 《IEEE transactions on information technology in biomedicine》2005,9(3):353-362
In the context of the Citizen Health System (CHS) project, a modular Medical Contact Center (MCC) was developed, which can be used in the monitoring, treatment, and management of chronically ill patients at home, such as diabetic or congestive heart failure patients. The virtue of the CHS contact center is that, using any type of communication and telematics technology, it is able to provide timely and preventive prompting to the patients, thus, achieving better disease management. In this paper, we present the structure of the CHS system, describing the modules that enable its flexible and extensible architecture. It is shown, through specific examples, how quality of healthcare delivery can be increased by using such a system. 相似文献
63.
Ioanna T. Nakou Dr. Matthew Jenner Dr. Yousef Dashti Dr. Isolda Romero-Canelón Dr. Joleen Masschelein Prof. Eshwar Mahenthiralingam Prof. Gregory L. Challis 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(51):23345-23353
A gene cluster encoding a cryptic trans-acyl transferase polyketide synthase (PKS) was identified in the genomes of Burkholderia gladioli BCC0238 and BCC1622, both isolated from the lungs of cystic fibrosis patients. Bioinfomatics analyses indicated the PKS assembles a novel member of the glutarimide class of antibiotics, hitherto only isolated from Streptomyces species. Screening of a range of growth parameters led to the identification of gladiostatin, the metabolic product of the PKS. NMR spectroscopic analysis revealed that gladiostatin, which has promising activity against several human cancer cell lines and inhibits tumor cell migration, contains an unusual 2-acyl-4-hydroxy-3-methylbutenolide in addition to the glutarimide pharmacophore. An AfsA-like domain at the C-terminus of the PKS was shown to catalyze condensation of 3-ketothioesters with dihydroxyacetone phosphate, thus indicating it plays a key role in polyketide chain release and butenolide formation. 相似文献
64.
Afroditi Papasavva Antonio Shegani Christos Kiritsis Ioanna Roupa Myrto Ischyropoulou Konstantina Makrypidi Irineos Pilatis George Loudos Maria Pelecanou Minas Papadopoulos Ioannis Pirmettis 《Molecules (Basel, Switzerland)》2021,26(16)
Sentinel lymph node detection (SLND) is rapidly entering common practice in the management of patients with tumors. The introduction of mannose molecules to 99mTc-labeled dextrans, so far, showed that the sentinel node could trap these agents due to their recognition by the mannose receptors of lymph node macrophages. The current study aimed to synthesize, characterize, and biologically evaluate a series of mannosylated dextran derivatives labeled with 99mTc for potential use in SLND. The compounds were designed to have a dextran with a molecular weight of 10–500 kDa as a backbone, S-derivatized cysteines, efficient SNO chelators, and mannose moieties for binding to mannose receptors. They were successfully synthesized, thoroughly characterized using NMR techniques, and labeled with the fac-[99mTc(CO)3]+ synthon. Labeling with high yields and radiochemical purities was achieved with all derivatives. In vivo biodistribution and imaging studies demonstrated high uptake in the first lymph node and low uptakes in the following node and confirmed the ability to visualize the SLN. Among the compounds studied, 99mTc-D75CM demonstrated the most attractive biological features, and in combination with the high radiochemical yield and stability of the compound, its further evaluation as a new radiopharmaceutical for sentinel lymph node detection was justified. 相似文献
65.
Konstantia Graikou Nektarios Aligiannis Ioanna Chinou Alexios‐Landros Skaltsounis Franois Tillequin Marc Litaudon 《Helvetica chimica acta》2005,88(10):2654-2660
Three new clerodane‐type terpenoids, furocrotinsulolide A ( 1 ), furocrotinsulolide B ( 2 ), and crotinsulactone ( 3 ), as well as a new phenolic disaccharide ( 4 ) have been isolated from the aerial parts of Croton insularis, together with eight known compounds. Their structures were established by in‐depth 1D‐ and 2D‐NMR spectroscopy, mass spectroscopy, and quantum‐mechanical calculations. 相似文献
66.
Elizabeth Yohannes Ioanna Salvarina 《Isotopes in environmental and health studies》2013,49(4):325-326
Abstract Biodegradation of polychlorinated biphenyls (PCBs) in soil is considered to be very complex due to various physico-chemical factors involved. Isotope labelling technique is the best to trace fate of the xenobiotic in the environment. In this work, the uniformly 14C-labelled PCB congener 11 (3,3′-chlorobiphenyl) was chosen as a low chlorinated coplanar biphenyl which was assumed to be readily degraded by microorganisms. Pleurotus ostreatus and two Pseudomonas species, representing white rot fungi and soil bacteria were used separately or in a consortium. The amount of liberated 14CO2 and radio-HPLC, HPLC, GC-MS, and radio-TLC analyses of extracts at the end of a two-month experiment showed that the mineralization of PCB 11 was < 0.4%, volatilization < 3.1%, and 30% of radioactivity was irreversibly bound to the soil matrix. The respective contents of all intermediate metabolites were 4.7 to 10.5 and 2.5 to 2.7% where Pseudomonas alcaligenes alone or in combination with P. putida was applied. 3-Chlorobenzoic acid was the major biodegradation product. 相似文献
67.
68.
Ioannou Katerina Hadjiyiannis Pantelis Liatsou Ioanna Pashalidis Ioannis 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(2):425-432
The removal of U(VI) by biochar fibers from aqueous solutions has been investigated prior and after MnO2 surface-deposition. The removal efficiency has been studied as a function of pH, U(VI) concentration, ionic strength, temperature and contact time. The fibers morphology and surface complexes were analyzed by SEM–EDX and FTIR, respectively. Evaluation of the experimental data indicates that the composite presents extraordinary adsorption capacity (qmax = 3.8 mmol g−1, 904 mg g−1), which is attributed to the formation of inner-sphere surface complexes, and that the adsorption reaction is a relatively fast, endothermic and entropy-driven process.
相似文献69.
Stephan Wagner Hendrik Auerbach Claudia E. Tait Ioanna Martinaiou Shyam C. N. Kumar Christian Kübel Ilya Sergeev Hans‐Christian Wille Jan Behrends Juliusz A. Wolny Volker Schünemann Ulrike I. Kramm 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(31):10596-10602
Fe–N–C catalysts are very promising materials for fuel cells and metal–air batteries. This work gives fundamental insights into the structural composition of an Fe–N–C catalyst and highlights the importance of an in‐depth characterization. By nuclear‐ and electron‐resonance techniques, we are able to show that even after mild pyrolysis and acid leaching, the catalyst contains considerable fractions of α‐iron and, surprisingly, iron oxide. Our work makes it questionable to what extent FeN4 sites can be present in Fe–N–C catalysts prepared by pyrolysis at 900 °C and above. The simulation of the iron partial density of phonon states enables the identification of three FeN4 species in our catalyst, one of them comprising a sixfold coordination with end‐on bonded oxygen as one of the axial ligands. 相似文献
70.
Metric Entropy of Convex Hulls in Banach Spaces 总被引:4,自引:0,他引:4
The paper presents diverse methods for estimating the coveringnumber of a precompact subset of a Banach space when the entropyof the set of its extremal points is already known. In the caseof a Hilbert space, the Gelfand diameters of the subset arealso estimated. 相似文献