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991.
The present study reports on the in vivo application of (Bio)silver nanocomposite formulations (LBPC-AgNCs) on wound healing. Additionally, the present study emphasizes the limited uptake of silver by liver and blood tissues as well as the high viability of PBMCs following external LBPC-AgNCs treatment. The wound closure was monitored via stereoscopic microscope, a localization case study in liver and blood tissue was carried out by (Inductively Coupled Plasma–Mass Spectrometers (ICP/MS), and peripheral blood mononuclear cells (PMBC) viability was determined via flow cytometry technique. The silver formulation was applied externally on the site of the wound infection for a period of ten days. At the beginning of the experiment, a moderate decrease in body weight and atypical behavior was observed. However, during the last period of the experiment, no abnormal mouse behaviors were noticed. The wound-healing process took place in a gradual manner, presenting the regeneration effect at around 30% from the fourth day. From the seventh day, the wounds treated with the silver formulation showed 80% of the wound healing potential. The viability of PBMCs was found to be 97%, whereas the concentrations of silver in the liver and blood samples were determined to be 0.022 µg/g and 9.3 µg/g, respectively. Furthermore, the present report becomes a pilot study in transferring from in vitro to in vivo scale (e.g., medical field application) once LBPC-AgNCs have demonstrated a unique wound healing potential as well as a non-toxic effect on the liver and blood.  相似文献   
992.
The JAK/STAT signal pathway is a system of intracellular proteins used by many cytokines and growth factors to express genes responsible for the process of cell activation, proliferation and differentiation. There has been numerous inflammatory and autoimmune diseases identified where the JAK/STAT signaling is disrupted; however, there are only a few papers concerning autoimmune bullous diseases published. The aim of this study was to evaluate the expression of proteins: JAK3, STAT2, STAT4 and STAT6 in epithelium lesions in patients with pemphigus vulgaris (PV), bullous pemphigoid (BP), oral lichen planus (LP) and chronic ulcerative stomatitis (CUS), as well as in the control group. Immunohistochemistry and immunoblotting were used to evaluate expression of selected proteins. We found significantly higher expression of selected JAK/STAT proteins in oral mucosa lesions in study groups in comparison to the control group, which indicates participation of JAK/STAT pathway in pathogenesis of these diseases. In BP and PV there were no increased STAT2 expression, whereas in CUS and LP no increased STAT4 expression occurred. The differences in expression of JAK/STAT proteins in selected disorders have been observed. These results create new potential therapeutic targets for the treatment.  相似文献   
993.
The aim of this study was to investigate the potential neurotoxic effect of the new anti-seizure medication candidate—5-(3-chlorophenyl)-4-hexyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (TP-315), after chronic administration to mice. TP-315 was administered to mice intraperitoneally for 14 days. At 24 h post the last injection, animals were decapitated, their brains were acquired, flash-frozen in liquid nitrogen and cut into 10 µm slices. The FT-IR chemical imaging technique was used for the investigation of the potential neurotoxic effect in the cerebral cortex and hippocampus. The effect on the lipidomic and proteomic profile and on oxidative stress was investigated. The results showed no statistically significant changes in the above-mentioned parameters. TP-315 seems to pose no neurotoxic effect on the mouse brain after chronic use, therefore, its use should be safe.  相似文献   
994.
We report a new structure of {[Co(bpy)2(ox)][{Cu2(bpy)2(ox)}Fe(ox)3]}n·8.5nH2O NCU-1 presenting a rare ladder topology among oxalate-based coordination polymers with anionic chains composed of alternately arranged [Cu2(bpy)2(ox)]2+ and [Fe(ox)3]3− moieties. Along the a axis, they are separated by Co(III) units to give porous material with voids of 963.7 Å3 (16.9% of cell volume). The stability of this structure is assured by a network of stacking interactions and charge-assisted C-H…O hydrogen bonds formed between adjacent chains, adjacent cobalt(III) units, and alternately arranged cobalt(III) and chain motifs. The soaking experiment with acetonitrile and bromobenzene showed that water molecules (8.5 water molecules dispersed over 15 positions) are bonded tightly, despite partial occupancy. Water adsorption experiments are described by a D’arcy and Watt model being the sum of Langmuir and Dubinin–Serpinski isotherms. The amount of primary adsorption sites calculated from this model is equal 8.2 mol H2O/mol, being very close to the value obtained from the XRD experiments and indicates that water was adsorbed mainly on the primary sites. The antiferromagnetic properties could be only approximately described with the simple CuII-ox-CuII dimer using H = −J·S1·S2, thus, considering non-trivial topology of the whole Cu-Fe chain, we developed our own general approach, based on the semiclassical model (SC) and molecular field (MF) model, to describe precisely the magnetic superexchange interactions in NCU-1. We established that Cu(II)-Cu(II) coupling dominates over multiple Cu(II)-Fe(III) interactions, with JCuCu = −275(29) and JCuFe = −3.8(1.6) cm−1 and discussed the obtained values against the literature data.  相似文献   
995.
A generalized model of the dynamics (GMD) of DC‐DC power electronic converters (PECs) is discussed in this paper. It is a geometrical piecewise‐affine continuous‐time model. The general idea of the GMD is to determine the local dynamic behavior of trajectories on the faces of the PEC commutation structure, which is a geometrical model of its commutation. This allows us to establish the direction of PEC dynamics on these faces. It can be either ‘entering’ into specific regions in state space or ‘exiting’ from them. Therefore, the local PEC dynamics can be treated as logical (two‐state). In practice, the GMD can be used for the analysis of PEC practical stability, which is a completely different concept from the concept of PEC stability in the classical Lyapunov sense. An outline of the design‐oriented approach to PEC practical stability analysis, which is based on the GMD, has also been presented. As illustrative examples, the GMD of a boost converter under peak current‐mode control and its application are presented. These examples show that the Lyapunov stability of a given PEC does not imply its practical stability, and that the results of PEC Lyapunov stability analysis and practical stability analysis are complementary to each other. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
996.
Against a background of hydrodynamic conditions connected with abandoning of significant number of mines and vast water reservoirs forming within them, basic methods of the assessment of strength of safety pillars used in coal mines in the USCB are presented. In the light of geomechanical research and conditions in mines in the USCB, the paper indicates a possibility of verification of safety pillar dimensions. On the example of one of mines in the USCB conditions for safety pillars stability in complicated mining conditions are assessed. The author also proposes a methodology of attempt and safety zones indication for existing safety pillars which would simultaneously be safety zones for designed exploitation.  相似文献   
997.
The global changes in energy policy, including the increasing contribution of renewable sources of energy to the total output of produced energy and various attempts to introduce advanced energy technologies, and the increasingly efficient use of the energy that had already been emitted are sufficient reasons to discuss Poland's energy policy. The present work features an analysis of the current state of Poland's energy economy and the economic factors that affect the power industry. The tenets of Poland's current energy policy are also presented in the context of hydrogen energy. The possibilities and limitations concerning the transition to hydrogen power in Poland are discussed taking into account a number of aspects, some of which include the degree of development of the electric power infrastructure, the current and future demand for electric energy with regard to the current geopolitical and economic situation of Poland, and Poland's membership in the European Union.  相似文献   
998.
A theoretical analysis and experimental investigation of the phenomenon of impingement of a circular liquid aerosol jet on a plate have been carried out. In the case considered, the spreading of liquid on a plate is caused by inertia and air drag force; for supercritical film flow in some conditions, a hydraulic jump is formed. The circular hydraulic jump exhibits behavior quite different than commonly observed in planar jumps. A new theoretical model of the phenomena of hydraulic jump has been formulated. The experiments exhibit that the liquid layer formed by an aerosol experiences a hydraulic jump at a location more downstream than the film created by a single-phase liquid jet. Theoretical results were compared with our experimental data, and the results seem to be satisfied.  相似文献   
999.
This study presents the results of investigations concerning variations in traits that effect structure of biomass yield in eight selected clones of common osier (Salix viminalis L.) from the willow collection at the University of Warmia and Mazury in Olsztyn. Additionally, analysis of clone/genotype interactions with years was performed for these traits. The study was conducted on two clones from the oldest Polish forms of common osier, namely, Paskówka and Gigantea. Three newer collected Polish common osier clones, and three clones from Swedish cultivars of common osier, were also used in this study. Early development stages of willow plants were investigated in field experiments. The study began with the planting of the willows and ended with harvesting after the third year of growth. The experiment was performed in the random block design in three replications. Analysis of variance on the tested clones of common osier with terms of their yield structure traits was performed on plant height, tillering, shoot diameter and yield. The analysis showed that a significant variation between clones begins in the second year of growth. Moreover, a significant genotype and environment interaction was found for all the willow clones, in terms of yield, which is expressed by the weight of one plant. However, this interaction for other traits was significant only in relation to certain clones. In the third year of cultivation old Polish willow clones in comparison with the Swedish and new Polish clones have higher plant weight (yield), tillering and shoot diameter.  相似文献   
1000.
We discovered adrenomedullin (AM) from human pheochromocytoma tissue by monitoring the elevating activity of intracellular cyclic AMP (cAMP) in rat platelets in 1993. Since the discovery of AM, it has attracted intense interest from cardiovascular researchers because AM elicits multiple biological activities, including a potent and powerful hypotensive activity caused by dilatation of resistance vessels. AM is biosynthesized and secreted from tissues, including cardiovascular organs. In addition to AM, "proadrenomedullin N-terminal 20 peptide (PAMP)," another biologically active peptide, was found to be processed from the AM precursor. Plasma AM levels are increased in various cardiovascular and renal diseases. AM, therefore, seems to function as a novel system that controls circulation and body fluid, and may be involved in pathophysiological changes in cardiovascular diseases. Therefore, in this review we will focus on the structure of AM and its gene, distribution, receptor, and the physiological and pathological roles of AM in cardiovascular disease.  相似文献   
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