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81.
X-ray imaging functionalization of biodegradable polyesters is a great demand and challenge in biomedical applications.In this work,a strategy of in-chain functionalization through the combination of ring opening copolymerization and oxime "Click" postfunctionalization was developed towards X-ray opaque polylactide copolymers.A functionalized cyclic carbonate was first synthesized and used as comonomer of polylactide copolymers,which were subjected to postfunctionalization of oxime "Click" reaction towards iodinated polylactide copolymers.The chemical structure and physical properties of the target products were traced and confirmed.In vitro cytotoxicity evaluation with 3T3-Swiss albino by Alamar blue demonstrated a low cytotoxicity.The X-ray radiopacity was analyzed by Micro-CT and quantified by Hounsfield Units value,which could be tailorable by the feedstock.It is a promising X-ray visible implantable biomaterial in biomedical applications. 相似文献
82.
Tomas Do Roman Guran Rea Jarosova Petra Ondrackova Zbysek Sladek Martin Faldyna Vojtech Adam Ondrej Zitka 《Molecules (Basel, Switzerland)》2020,25(23)
Respiratory infections are a real threat for humans, and therefore the pig model is of interest for studies. As one of a case for studies, Actinobacillus pleuropneumoniae (APP) caused infections and still worries many pig breeders around the world. To better understand the influence of pathogenic effect of APP on a respiratory system—lungs and tracheobronchial lymph nodes (TBLN), we aimed to employ matrix-assisted laser desorption/ionization time-of-flight mass spectrometry imaging (MALDI-TOF MSI). In this study, six pigs were intranasally infected by APP and two were used as non-infected control, and 48 cryosections have been obtained. MALDI-TOF MSI and immunohistochemistry (IHC) were used to study spatial distribution of infectious markers, especially interleukins, in cryosections of porcine tissues of lungs (necrotic area, marginal zone) and tracheobronchial lymph nodes (TBLN) from pigs infected by APP. CD163, interleukin 1β (IL-1β) and a protegrin-4 precursor were successfully detected based on their tryptic fragments. CD163 and IL-1β were confirmed also by IHC. The protegrin-4 precursor was identified by MALDI-TOF/TOF directly on the tissue cryosections. CD163, IL-1β and protegrin-4 precursor were all significantly (p < 0.001) more expressed in necrotic areas of lungs infected by APP than in marginal zone, TBLN and in control lungs. 相似文献
83.
铁在自然界中含量丰富,化学性质活泼,能够形成多种应用广泛的物质及材料,富有发展潜力。简述了铁元素的发现与性质,并重点介绍了铁的功能与应用。其中铁的应用主要围绕铁及其化合物在医学治疗、能源材料和环境保护领域所发挥的重要作用进行了阐述。 相似文献
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ABSTRACTWe study the structural, energetic and electronic properties of the structured water chain clusters within the density functional theory. We refer the structured water chains to those water clusters that have specific geometric patterns stretched along one direction. External electric field required to keep the structures open chain, thereby preventing them to form closed structures, is applied along the length of the chain. The structures are essentially periodic with basic repeating unit consisting of the corner- or edge-sharing 4-, 5- or 6-membered ring water clusters. Our calculations underscore the possible existence of such structured water clusters in the electrostatic environments, which we simulate in its simplicity employing a dipolar, uniform and static electric field. Analysis reveals that the 5-membered ring water chain clusters, i.e. the pentamer chain clusters have the lowest average dipole moment per water molecule while the threshold field, that marks the onset of the field-induced closure of the HOMO (highest occupied molecular orbital)-LUMO (lowest unoccupied molecular orbital) energy gap, is highest, followed by that for the tetramer and hexamer chains. The results suggest that the pentamer chains are the most stable clusters over a wide range of electric fields. 相似文献
87.
ABSTRACTThis study computes the potential energy curves of the X1Σ+, A1Π, B1Δ, C1Σ+, and D1Π states of AlO+ cation and the transition dipole moments between them. The orders of the rotationless radiative lifetimes are 10–100?μs for the A1Π state, 1–1000?ms for the B1Δ state, 10?ns for the first well and 100?ns for the second well of the C1Σ+ state, and 1?μs for the D1Π state. Emissions of the B1Δ–A1Π and D1Π–C1Σ+ systems are so weak that they are hardly measured via spectroscopy, the emissions of the C1Σ+–X1Σ+, C1Σ+–A1Π, and D1Π–X1Σ+ systems are so strong that they can be detected readily, and emissions of the A1Π–X1Σ+ and D1Π–A1Π systems can be observed through spectroscopy only by a significant effort. There is a strong great similarity between spontaneous emissions of the A1Π–X1Σ+ system of the AlO+ cation and the A2Π–X2Σ+ system of the AlO radical. The emissions of the A2Π–X2Σ+ system of the AlO radical have been measured in outer space Therefore, it is highly possible that the emissions of the A1Π–X1Σ+ system of the AlO+ cation can be detected in the astrophysical media. 相似文献
88.
Florio M. Ciaglia Fabio Di Cosmo Alberto Ibort Giuseppe Marmo 《Entropy (Basel, Switzerland)》2020,22(11)
The evolution of states of the composition of classical and quantum systems in the groupoid formalism for physical theories introduced recently is discussed. It is shown that the notion of a classical system, in the sense of Birkhoff and von Neumann, is equivalent, in the case of systems with a countable number of outputs, to a totally disconnected groupoid with Abelian von Neumann algebra. The impossibility of evolving a separable state of a composite system made up of a classical and a quantum one into an entangled state by means of a unitary evolution is proven in accordance with Raggio’s theorem, which is extended to include a new family of separable states corresponding to the composition of a system with a totally disconnected space of outcomes and a quantum one. 相似文献
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