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31.
Liliana Mititelu-Tartau Maria Bogdan Daniela Angelica Pricop Beatrice Rozalina Buca Ana-Maria Pauna Lorena Anda Dijmarescu Ana-Maria Pelin Liliana Lacramioara Pavel Gratiela Eliza Popa 《Molecules (Basel, Switzerland)》2021,26(13)
This paper is focused on the in vivo release and biocompatibility evaluation in rats of some novel systems entrapping zinc chloride in lipid vesicles. The particles were prepared by zinc chloride immobilization inside lipid vesicles made using phosphatidylcholine, stabilized with 0.5% chitosan solution, and dialyzed for 10 h to achieve a neutral pH. The submicrometric systems were physico-chemically characterized. White Wistar rats, assigned into four groups of six animals each, were treated orally with a single dose, as follows: Group I (control): deionized water 0.3 mL/100 g body weight; Group II (Zn): 2 mg/kg body weight (kbw) zinc chloride; Group III (LV-Zn): 2 mg/kbw zinc chloride in vesicles; Group IV (LVC-Zn): 2 mg/kbw zinc chloride in vesicles stabilized with chitosan. Haematological, biochemical, and immune parameters were assessed after 24 h and 7 days, and then liver fragments were collected for histopathological examination. The use of zinc submicrometric particles—especially those stabilized with chitosan—showed a delayed zinc release in rats. No substantial changes to blood parameters, plasma biochemical tests, serum complement activity, or peripheral neutrophils phagocytic capacity were noted; moreover, the tested substances did not induce liver architectural disturbances. The obtained systems provided a delayed release of zinc, and showed good biocompatibility in rats. 相似文献
32.
33.
We show that ghosts in gauge theories can be interpreted as Maurer-Cartan forms in the infinite dimensional group ? of gauge transformations. We examine the cohomology of the Lie algebra of ? and identify the coboundary operator with the BRS operator. We describe the anomalous terms encountered in the renormalization of gauge theories (triangle anomalies) as elements of these cohomology groups. 相似文献
34.
We discuss the structure of a particle system obtained in “aesthetic” field theory and study the evolution of this system in time. We find the particle system to have more structure than particles found by other authors investigating particlelike behavior in nonlinear field theories. Our particle system has a maximum center in proximity to a minimum center. Thus, we can interpret our system as being constructed of two bodies. We find that the maximum center and the minimum center move in straight lines, to computer accuracy. Thus, we have not found any nontrivial force laws. This suggests that the situation with respect to basic principles be kept fluid. So far as we know, we are the first investigators to study the trajectories of a two-body system which arises as a consequence of nonlinear field equations. 相似文献
35.
Astrid Zürn Beatrice Rabolt Manfred Gräfe Helmut Müller 《Fresenius' Journal of Analytical Chemistry》1994,349(8-9):666-669
A photolithographically fabricated membrane for enzyme immobilisation based on an Ion Sensitive Field Effect Transistor (ISFET) is described. The preparation of an Enzyme-FET (ENFET) containing urease was successful. The ENFET has been used for the determination of urea and pesticides; this depends on the chosen enzyme level in the membrane and can be employed in a flow-injection system. The urea sensitive sensor (high enzyme load) has a wide linear range (1–500 mmol/l) a fast response (t95=20 s) and a lifetime greater than 30 days. The application of this sensor to the determination of urea in the waste water from a fertilizer plant and in blood serum is discussed. The second sensor (low enzyme level) was able to detect pesticides in water based on the inhibition of urease. The detection limit was found to be 0.1 µg/l for Carbofuran (10 minutes incubation time, without preconcentration). 相似文献
36.
Costa D. P. T. S. Beatrice L. C. S. Guerra L. S. C. Ribeiro M. A. Zanin F. A. A. Queiroga A. S. Limeira Júnior F. A. Gerbi M. E. M. M. 《Laser Physics》2010,20(4):876-880
Laser Physics - The aim of the present study was to compare marginal infiltration in Class V cavities prepared on extracted human premolars with either high-speed rotation or a Er:YAG laser. Class... 相似文献
37.
Zanchet A Bussery-Honvault B Honvault P 《The journal of physical chemistry. A》2006,110(43):12017-12025
The C((3)P) + OH(X (2)Pi) --> CO(X (1)Sigma(g)(+)) + H((2)S) reaction has been investigated by ab initio electronic structure calculations of the X(2)A' state based on the multireference (MR) internally contracted single and double configuration interaction (SDCI) method plus Davidson correction (+Q) using Dunning aug-cc-pVQZ basis sets. In particular, the multireference space is taken to be a complete active space (CAS). Improvement over previously proposed potential energy surfaces for HCO/COH is obtained in the sense that present surface describes also the potential part where the CO interatomic distance is large. A large number of geometries (around 2000) have been calculated and analytically fitted using the reproducing kernel Hilbert space (RKHS) method of Ho and Rabitz both for the two-body and three-body terms following the many-body decomposition of the total electronic energies. Results show that the global reaction is highly exothermic ( approximately 6.4 eV) and barrierless (relative to the reactant channel), while five potential barriers are located on this surface. The three minima and five saddle points observed are characterized and found to be in good agreement with previous work. The three minima correspond to the formation of HCO and COH complexes and to the CO + H products, with the COH complex being a metastable minimum relative to the product channel. The five saddle points correspond to potential barriers for both the dissociation/formation of HCO and COH into/from CO + H, to barriers for the isomerization of HCO into COH and to barriers for the inversion of HCO and COH through their respective linear configuration. 相似文献
38.
The automorphic G-chromatic index of a graph Γ is the minimum integer m for which Γ has a proper edge-coloring with m colors which is preserved by the full automorphism group G of Γ. We determine the automorphic G-chromatic index of each member of four infinite classes of snarks: type I Blanu?a snarks, type II Blanu?a snarks, Flower snarks and Goldberg snarks. 相似文献
39.
An existence result of multiple solutions for a fourth-order Sturm-Liouville boundary value problem with variable parameters is established. As a consequence, three solutions for a boundary value problem with a fourth-order equation in a complete form are obtained. Our approach is based on variational methods. 相似文献
40.
The search for analytic solutions in open string fields theory à la Witten often meets with singular expressions, which need an adequate mathematical formalism to be interpreted. In this paper we discuss this problem and propose a way to resolve the related ambiguities. Our claim is that a correct interpretation requires a formalism similar to distribution theory in functional analysis. To this end we concretely construct a locally convex space of test string states together with the dual space of functionals. We show that the above suspicious expressions can be identified with well defined elements of the dual. 相似文献