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991.
We investigated the presence of a molecular pathway from hepatic 11-βHSD-1 to brain MAO-A in the dynamics of plasma corticosterone involvement in anxiety development. During 14 days following repeated exposure of rats to predator scent stress for 10 days, the following variables were measured: hepatic 11-βHSD-1 and brain MAO-A activities, brain norepinephrine, plasma corticosterone concentrations, and anxiety, as reflected by performance on an elevated plus maze. Anxiety briefly decreased and then increased after stress exposure. This behavioral response correlated inversely with plasma corticosterone and with brain MAO-A activity. A mathematical model described the dynamics of the biochemical variables and predicted the factor(s) responsible for the development and dynamics of anxiety. In the model, hepatic 11-βHSD-1 was considered a key factor in defining the dynamics of plasma corticosterone. In turn, plasma corticosterone and oxidation of brain ketodienes and conjugated trienes determined the dynamics of brain MAO-A activity, and MAO-A activity determined the dynamics of brain norepinephrine. Finally, plasma corticosterone was modeled as the determinant of anxiety. Solution of the model equations demonstrated that plasma corticosterone is mainly determined by the activity of hepatic 11-βHSD-1 and, most importantly, that corticosterone plays a critical role in the dynamics of anxiety following repeated stress.  相似文献   
992.
The ability of TiO2 to generate reactive oxygen species under UV radiation makes it an efficient candidate in antimicrobial studies. In this context, the preparation of TiO2 microparticles coated with Ca- and Cu-based composite layers over which Cu(II), Cu(I), and Cu(0) species were identified is presented here. The obtained materials were characterized by a wide range of analytical methods, such as X-ray diffraction, electron microscopy (TEM, SEM), X-ray photoelectron (XPS), and UV-VIS spectroscopy. The antimicrobial efficiency was evaluated using qualitative and quantitative standard methods and standard clinical microbial strains. A significant aspect of this composite is that the antimicrobial properties were evidenced both in the presence and absence of the light, as result of competition between photo and electrical effects. However, the antibacterial effect was similar in darkness and light for all samples. Because no photocatalytic properties were found in the absence of copper, the results sustain the antibacterial effect of the electric field (generated by the electrostatic potential of the composite layer) both under the dark and in light conditions. In this way, the composite layers supported on the TiO2 microparticles’ surface can offer continuous antibacterial protection and do not require the presence of a permanent light source for activation. However, the antimicrobial effect in the dark is more significant and is considered to be the result of the electric field effect generated on the composite layer.  相似文献   
993.
The synthesis and structural characterization of a series of supramolecular complexes of bicyclic cationic pyridine-fused 1,2,4-selenodiazoles with various anions is reported. The binding of trifluoroacetate, tetrachloroaurate, tetraphenylborate, perrhenate, and pertechnetate anions in the solid state is regarded. All the anions interact with selenodiazolium cations exclusively via a pair of “chelating” Se⋯O and H⋯O non-covalent interactions, which make them an attractive, novel, non-classical supramolecular recognition unit or a synthon. Trifluoroacetate salts were conveniently generated via novel oxidation reaction of 2,2′-dipyridyl diselenide with bis(trifluoroacetoxy)iodo)benzene in the presence of corresponding nitriles. Isolation and structural characterization of transient 2-pyridylselenyl trifluoroacetate was achieved. X-ray analysis has demonstrated that the latter forms dimers in the solid state featuring very short and strong Se⋯O and Se⋯N ChB contacts. 1,2,4-Selenodiazolium trifluoroacetates or halides show good solubility in water. In contrast, (AuCl4), (ReO4), or (TcO4) derivatives immediately precipitate from aqueous solutions. Structural features of these supramolecular complexes in the solid state are discussed. The nature and energies of the non-covalent interactions in novel assembles were studied by the theoretical methods. To the best of our knowledge, this is the first study that regards perrhenate and pertechnetate as acceptors in ChB interactions. The results presented here will be useful for further developments in anion recognition and precipitation involving cationic 1,2,4-selenodiazoles.  相似文献   
994.
Neuroblastoma (NB) is a pediatric cancer with high clinical and molecular heterogeneity, and patients with high-risk tumors have limited treatment options. Receptor tyrosine kinase KIT has been identified as a potential marker of high-risk NB and a promising target for NB treatment. We investigated 19,145 tumor RNA expression and molecular pathway activation profiles for 20 cancer types and detected relatively high levels of KIT expression in NB. Increased KIT expression was associated with activation of cell survival pathways, downregulated apoptosis induction, and cell cycle checkpoint control pathways. KIT knockdown with shRNA encoded by lentiviral vectors in SH-SY5Y cells led to reduced cell proliferation and apoptosis induction up to 50%. Our data suggest that apoptosis induction was caused by mitotic catastrophe, and there was a 2-fold decrease in percentage of G2-M cell cycle phase after KIT knockdown. We found that KIT knockdown in NB cells leads to strong upregulation of other pro-survival growth factor signaling cascades such as EPO, NGF, IL-6, and IGF-1 pathways. NGF, IGF-1 and EPO were able to increase cell proliferation in KIT-depleted cells in an ERK1/2-dependent manner. Overall, we show that KIT is a promising therapeutic target in NB, although such therapy efficiency could be impeded by growth factor signaling activation.  相似文献   
995.
Die Sauerstoffionenleitung in stabilisiertem Zirkondioxyd. CaO-stabilisiertes Zirkondioxyd als Elektrolyt in Sauerstoffkonzentrationsketten. Elektrochemische Bestimmung der Sauerstoffpartialdrücke in H2O-H2-Gasgemischen an der Kette Luft/ZrO2 + CaO/H2O, H2 bei 800 bis 1750 °C und in sauerstoffhaltigen Eisenschmelzen an der Kette H2O, H2/ZrO2 + CaO/[O]Fe bei 1550 bis 1750 °C. Ermittlung der Temperaturabhängigkeit der Freien Enthalpie für die Reaktionen {H2} + 1/2 {O2} = {H2O} und 1/2 {O2} = [O]Fe. Berechnung der Überführungszahlen der Ionen und der kritischen Sauerstoffdrücke der beginnenden Elektronenleitung für den ZrO2-CaO-Elektrolyten.  相似文献   
996.
These minutes are the official record of the actions of the Association taken during the year by both the Board of Directors (the Board) and the Council of Representatives (Council). The roll of representatives was called at each Council meeting, and more than a quorum answered to their names. Reference is made in these minutes to various reports, some of which will be published elsewhere. Copies of these reports were distributed to Council and are on file in the Central Office. As long as the supply lasts, extra copies of many of the reports are available from the Central Office. These minutes are arranged in topical rather than chronological order, and subheadings are used when appropriate. The main topical headings are I. Minutes of Meetings; II. Elections, Awards, Membership, and Human Resources; III. Ethics; IV. Board of Directors; V. Divisions and State, Provincial, and Territorial Psychological Associations; VI. Organization of the APA; VII. Publications and Communications; VIII. Convention Affairs; IX. Educational Affairs; X. Professional Affairs; XI. Scientific Affairs; XII. Public Interest; XIII. Ethnic Minority Affairs; XIV. International Affairs; XV. Central Office; and XVI. Financial Affairs. Changes to the language of the American Psychological Association (APA) Bylaws, Association Rules, or motions of the items are noted as follows throughout these proceedings: Bracketed material is to be deleted; underlined material is to be added. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
These minutes are the official record of the actions of the Association taken during the year by both the Board of Directors (the Board) and the Council of Representatives (Council). The roll of representatives was called at each Council meeting, and more than a quorum answered to their names. Reference is made in these minutes to various reports, some of which will be published elsewhere. Copies of these reports were distributed to Council and are on file in the Central Office. As long as the supply lasts, extra copies of many of the reports are available from the Central Office. These minutes are arranged in topical rather than chronological order, and subheadings are used when appropriate. The main topical headings are I. Minutes of Meetings; II. Elections, Awards, Membership, and Human Resources; III. Ethics; IV. Board of Directors; V. Divisions and State, Provincial, and Territorial Associations; VI. Organization of the APA; VII. Publications and Communications; VIII. Convention Affairs; IX. Educational Affairs; X. Professional Affairs; XI. Scientific Affairs; XII. Public Interest; XIII. Ethnic Minority Affairs; XIV. International Affairs; XV. Central Office; and XVI. Financial Affairs. Changes to the language of the American Psychological Association (APA) Bylaws, Association Rules, or motions of the items are noted as follows throughout these proceedings: Bracketed material is to be deleted; underlined material is to be added. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
998.
Kritische Überprüfung des Anwendungsbereichs von stabilisiertem Zirkonoxid, Mullit und Magnesiumoxid in einer Festelektrolytzelle mit Luft als Sauerstoffvergleichspotential. Nachweis der Sauerstoffdurchlässigkeit fester Elektrolyte und der Ausbildung von Sauerstoffdiffusionsschichten an der Phasengrenze Festelektrolyt/Eisenschmelze. Voraussetzungen für eine korrekturfreie elektrochemische Sauerstoffbestimmung in Eisenschmelzen bei Verwendung von gasförmigen Sauerstoffvergleichspotentialen.  相似文献   
999.
Despite the great potential of octahedral tungsten cluster complexes in fields of biomedical applications such as X-ray computed tomography or angiography, there is only one example of a water-soluble W6Q8-cluster that has been reported in the literature. Herein we present the synthesis and a detailed characterization including X-ray structural analysis, NMR, IR, UV–Vis spectroscopies, HR-MS spectrometry, and the electrochemical behavior of two new cluster complexes of the general formula W6Q8L6 with phosphine ligands containing a hydrophilic carboxylic group, which makes the complexes soluble in an aqueous medium. The hydrolytic stability of the clusters’ aqueous solutions allows us to investigate for the first time the influence of W6-clusters on cell viability. The results obtained clearly demonstrate their very low cytotoxicity, comparable to the least-toxic clusters presented in the literature.  相似文献   
1000.
Semi-global stabilization and output regulation of linear systems subject to state and/or input constraints have been studied in our earlier work by using state feedback. For the same problems, observer based measurement feedback control designs are the topics of this paper. High-gain observers are used in the feedback design in order to obtain accurate estimates of the state so that the constraint violation can be avoided. Due to the peaking phenomenon associated with a high-gain observer, a special saturation protection is built in the control laws to avoid possible constraint violation. The results in this paper show that the semi-global stabilization and semi-global output regulation problems for constrained linear systems are solvable via measurement feedback under solvability conditions similar to those in the state feedback.  相似文献   
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