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排序方式: 共有403条查询结果,搜索用时 15 毫秒
81.
Anna Sykua Adriana Nowak Eugenio Garribba Aliaksandr Dzeikala Magdalena Rowiska-yrek Justyna Czerwiska Waldemar Maniukiewicz Elbieta odyga-Chruciska 《International journal of molecular sciences》2023,24(1)
The three Schiff base ligands, derivatives of hesperetin, HHSB (N-[2,3-dihydro-5,7-dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chromen-4-ylidene]isonicotinohydrazide), HIN (N-[2,3-dihydro-5,7-dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chromen-4-ylidene]benzhydrazide) and HTSC (N-[2,3-dihydro-5,7-dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chromen-4-ylidene]thiosemicarbazide) and their copper complexes, CuHHSB, CuHIN, and CuHTSC were designed, synthesized and analyzed in terms of their spectral characterization and the genotoxic activity. Their structures were established using several methods: elemental analysis, FT-IR, UV-Vis, EPR, and ESI-MS. Spectral data showed that in the acetate complexes the tested Schiff bases act as neutral tridentate ligand coordinating to the copper ion through two oxygen (or oxygen and sulphur) donor atoms and a nitrogen donor atom. EPR measurements indicate that in solution the complexes keep their structures with the ligands remaining bound to copper(II) in a tridentate fashion with (O–, N, Oket) or (O–, N, S) donor set. The genotoxic activity of the compounds was tested against model tumour (HeLa and Caco-2) and normal (LLC-PK1) cell lines. In HeLa cells the genotoxicity for all tested compounds was noticed, for HHSB and CuHHSB was the highest, for HTSC and CuHTSC–the lowest. Generally, Cu complexes displayed lower genotoxicity to HeLa cells than ligands. In the case of Caco-2 cell line HHSB and HTSC induced the strongest breaks to DNA. On the other side, CuHHSB and CuHTSC induced the highest DNA damage against LLC-PK1. 相似文献
82.
Tomasz Urbanowicz Anna Olasiska-Winiewska Marcin Gadki Micha Michalak Mateusz Sochacki Anita Weclewska Dominika Zalas Waldemar Bobkowski Marek Jemielity 《International journal of molecular sciences》2022,23(20)
Neutrophils play a significant role in immune and inflammatory reactions. The preoperative inflammatory activation may have a detrimental effect on postoperative outcomes. The aim of the study was to investigate the relation between preoperative hematological indices on postoperative complications’ risk in pediatric cardiac congenital surgery. The retrospective single center analysis included 93 pediatric patients (48 (65%) males and 45 (35%) females), mean age of 7 (3–30) months referred for cardiac surgery in cardiopulmonary bypass due to functional single ventricle disease (26 procedures), shunts lesions (40 procedures) and cyanotic disease (27 procedures). Among simple hematological indices, the receiver-operating-characteristic curve showed that a neutrophil count below 2.59 K/uL was found as an optimal cut-off point for predicting postoperative atrioventricular block following pediatric cardiac surgery (AUC = 0.845, p < 0.0001) yielding a sensitivity of 100% and a specificity of 65.62%. Preoperative values of neutrophil count below 2.59 K/uL in whole blood analysis can be regarded as a predictive factor (AUC = 0.845, p < 0.0001) for postoperative atrioventricular block in pediatric cardiac surgery. 相似文献
83.
Alfons Schloemer Waldemar Godbersen und Max Ohm 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1940,79(4):337-344
Zusammenfassung Bericht über die gemeinsame Kontrolle des Groß-Berliner Buttermarktes durch die Kontrollorgane der amtlichen Lebensmittelkontrolle, den Gewerbe-Außendienst der Polizei und die Preußische Landesanstalt zusammen mit den Buttersachverständigen der Hauptvereinigung der deutschen Milch- und Fettwirtschaft, sowie des Milch- und Fettwirtschaftsverbandes Kurmark im Jahre 1939; ambulante Kontrolle, Methodik der polizeilichen Probenahme, Begleitbogen, Prüfung der Butterproben bezüglich Kennzeichnung, Form, Gewicht, Perforierung, Wassergehalt, Verfälschung mit fremden Fetten sowie Sinnenprüfung; Beurteilung der Proben auf Grund der verschiedenen, hier angeführten Gesetze, Verordnungen und Anordnungen. 相似文献
84.
Kornelia Wiśniewska Waldemar Pichór Ewelina Kłosek-Wawrzyn 《International Journal of Applied Ceramic Technology》2021,18(3):1063-1073
Sintered ceramics, represented by ceramic tiles or clinker bricks, are widely used in the building materials industry due to their technological properties and visual qualities. The topic of color changing of ceramic materials from cream-firing clays with the use of mineral additives has not been addressed to date. The aim of the paper was to investigate the effect of granulation of dolomite additives to ceramic masses based on cream-firing Borkowice clay on the color and properties of fired ceramic materials. The paper proposes that grain size of mineral additive affects the color of sintered ceramics. In order to confirm this hypothesis, a number of experiments were performed, consisting of determination of the color and technological properties of ceramic materials. The conducted tests showed that the color and technological properties of sintered ceramics are influenced by the grain size of the additives used. 相似文献
85.
The ideal plug flow reactor is a common model with narrow residence time distribution in reaction engineering. This contribution explains a design strategy of a coiled flow inverter (CFI) with narrow residence time and flexible adjustable process conditions. The design space diagram illustrates the design limits of inner diameter and coil diameter on the base of dimensionless numbers. Standard coil tube diameters allow for rational design of a limited number of devices. The reactor performance diagram enables the facile scale‐up and adaption of new process conditions with the CFI with economic boundary conditions. 相似文献
86.
87.
The main objective of this study was to identify critical factors that measure management efforts with regard to quality, safety, and ergonomics issues for their simultaneous improvement. Eleven identified management activity areas have been synthesized from the literature as the most important areas that meet all stakeholders' needs. Factors were then developed to measure the efficiency of these activities through a questionnaire. The overall response rate of the survey questionnaire was 47%. The reliability coefficients ranging from 0.73 to 0.85 indicated that some scales or management activity areas are more reliable in measuring potential for improvements in terms of quality, ergonomics, safety, and efficiency. The proposed instrument for quantifying management efforts with respect to simultaneous improvements in the areas of quality, ergonomics, and safety was found to be valid and reliable. © 2005 Wiley Periodicals, Inc. Hum Factors Man 15: 213–232, 2005. 相似文献
88.
Hydrolysis of Phosphatidylcholine-Isoprostanes (PtdCho-IP) by Peripheral Human Group IIA,V and X Secretory Phospholipases A<Subscript>2</Subscript> (sPLA<Subscript>2</Subscript>)
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Biologically active F- and E/D-type-prostane ring isomers (F2-IP and E2/D2-IP, respectively) are produced in situ by non-enzymatic peroxidation of arachidonic acid esterified to GroPCho (PtdCho-IP) and are universally distributed in tissue lipoproteins and cell membranes. Previous work has shown that platelet-activating factor acetylhydrolases (PAF-AH) are the main endogenous PLA2 involved in degradation of PtdCho-IP. The present study shows that the PtdCho-IP are also subject to hydrolysis by group IIA, V and X secretory PLA2, which also have a wide peripheral tissue distribution. For this demonstration, we compared the LC/MS profiles of PtdCho-IP of auto-oxidized plasma lipoproteins after incubation for 1–4 h (37 °C) in the absence or presence of recombinant human sPLA2 (1–2.5 µg/ml). In the absence of exogenously added sPLA2 the total PtdCho-IP level after 4 h incubation reached 15.9, 21.6 and 8.7 nmol/mg protein of LDL, HDL and HDL3, respectively. In the presence of group V or group X sPLA2 (2.5 µg/ml), the PtdCho-IP was completely hydrolyzed in 1 h, while in the presence of group IIA sPLA2 (2.5 µg/ml) the hydrolysis was less than 25% in 4 h, although it was complete after 8–24 h incubation. This report provides the first demonstration that PtdCho-IP are readily hydrolyzed by group IIA, V and X sPLA2. A co-location of sPLA2 and the substrates in various tissues has been recorded. Thus, the initiation of interaction and production of isoprostanes in situ are highly probable. 相似文献
89.
Proper conditioning of an oil sand/water slurry is essential for the efficient extraction of bitumen. The conditioning process depends on such variables as ore grade, temperature, mixing intensity, mixing time, and water composition. A technique has been developed in which a microscope and video cameras are used to observe a slurry stirred in a glass cell to evaluate, on a comparative basis, the effect of conditioning parameters on bitumen recovery. Several ores and their blends were studied and found to exhibit large differences in their conditioning behaviour. The method offers the capability of diagnosing ore processability problems and optimizing slurry conditioning. 相似文献
90.
Zirconia polycrystals stabilised with 7 mol.% CaO containing 10 vol.% WC particles (Ca-PSZ/WC) were obtained by using zirconia nanopowder and WC micropowder. Cold isostatically pressed samples were pressureless sintered in argon at 1350–1950 °C. The influence of the sintering temperature and the incorporation of WC particles on the phase composition and mechanical properties of the composites were studied. Decomposition of WC due to the reaction with the zirconia matrix was found. W2C and metallic tungsten were detected as decomposition products when heat treated below 1750 °C. At higher temperatures, ZrC is formed. The mechanism of WC decomposition was discussed. The zirconia polycrystals modified with in situ formed W and W2C inclusions showed a bending strength of 417 ± 67 MPa, a fracture toughness of 5.2 ± 0.3 MPa m0.5 and a hardness of 14.6 ± 0.3 GPa. 相似文献