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61.
Agata Tarkowska Wanda Furmaga-Jaboska Jacek Bogucki Janusz Kocki Ryszard Pluta 《International journal of molecular sciences》2021,22(10)
Perinatal asphyxia is mainly a brain disease leading to the development of neurodegeneration, in which a number of peripheral lesions have been identified; however, little is known about the expression of key genes involved in amyloid production by peripheral cells, such as lymphocytes, during the development of hypoxic-ischemic encephalopathy. We analyzed the gene expression of the amyloid protein precursor, β-secretase, presenilin 1 and 2 and hypoxia-inducible factor 1-α by RT-PCR in the lymphocytes of post-asphyxia and control neonates. In all examined periods after asphyxia, decreased expression of the genes of the amyloid protein precursor, β-secretase and hypoxia-inducible factor 1-α was noted in lymphocytes. Conversely, expression of presenilin 1 and 2 genes decreased on days 1–7 and 8–14 but increased after survival for more than 15 days. We believe that the expression of presenilin genes in lymphocytes could be a potential biomarker to determine the severity of the post-asphyxia neurodegeneration or to identify the underlying factors for brain neurodegeneration and get information about the time they occurred. This appears to be the first worldwide data on the role of the presenilin 1 and 2 genes associated with Alzheimer’s disease in the dysregulation of neonatal lymphocytes after perinatal asphyxia. 相似文献
62.
The mechanism of synergistic extraction of gold in HCl media was researched with tri-n-octyl amine(TOA) and tri-n-octyl phospine
oxide(TOPO). It was determined that the composition of synergistic extract is (TOAHTOPO) AuCl4; the constant of synergistic extracting equilibrium is 109.20; and the synergistic reaction is exothermic with − 17.187 kJ/K· mol of ΔH
298. The extraction mechanism was also studied by the IR-spectra and UV-spectra. It is found that the extraction mechanism belongs
to ion-association type.
Synopsis of the first author Yang Tianzu, professor, born in April 1958, majoring in the metallurgy of precious metals and coordination chemistry in hydrometallurgy. 相似文献
63.
Zdzislaw Paryzek Monika Piasecka Roman Joachimiak Emilia Luks Wanda Radecka-Paryzek 《中国稀土学报(英文版)》2010
New steroid dimer, ethylene bridged bis-carbamate (3) was synthesized from cholic acid in few steps. Complexes of 3 with lanthanum(III) and calcium(II) nitrates were prepared in reaction of 3 and appropriate metal salts. They were characterized by spectral data (Infrared (IR), ultraviolet-visible (UV/Vis), nuclear magnetic resonance (NMR) spectroscopy and fast-atom bombardment (FAB), electrospray (ESI) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS)) and elemental analysis. The similarity in complexing behavior of steroidal dimer toward calcium and lanthanum ions was observed. 相似文献
64.
The self-assembled formation of a one-dimensional lanthanum salicylaldimine coordination polymer was proved by the X-ray diffraction analysis of new lanthanum(III) nitrate complex containing N,N'-bis(salicylidene)-1,5-pentanediamine ligand (H2L). It was obtained in situ in a one-step, metal-templated condensation of salicylaldehyde with 1,5-pentanediamine (cadaverine, biogenic polyamine) and characterized by microanalysis and spectroscopic (IR, ESI-MS, UV-Vis, and 1H NMR) data. The [La(NO3)3(μ-H2L)2]∞ complex displayed 10-coordinate distorted bicapped dodecahedron geometry with unusual coordination pattern of undeprotonated salicylaldimines which acted as μ-bridging ditopic ligands using exclusively the oxygens as donor atoms with the nitrogen atoms not being involved in the coordination environment. 相似文献
65.
在湿度恒定、温度变化的强制干燥条件下,为了探讨在重涂间隔时间内温度对水分挥发速度和挥发量的影响,本研究以枫木薄木贴面家具板件为基材,以单组分水性封闭底漆为涂料,在相对湿度恒定为50%、温度为15~35℃范围内强制干燥涂层,研究涂层的水分挥发规律。结果表明:随时间的推移,同一温度条件下,水性封闭底漆的水分挥发率不断增加,水分挥发速度逐渐降低;不同温度条件下,水分挥发率和挥发速度差异不明显;相同的时间段内,在15~25℃温度范围内水分挥发率的差异程度要小于25~35℃的干燥条件;随着时间的推移,水分挥发速度的差距越来越不明显。 相似文献
66.
Piotr P. Lewicki Dorota Witrowa‐Rajchert Wanda Pomaranska‐Lazuka Dorota Nowak 《International Journal of Food Properties》2013,16(3):275-290
Abstract The effect of pretreatment preceding convective drying and the mode of drying on reconstitution properties of dried onion was investigated. Soaking in water, dipping in starch solution and osmotic dewatering were used as pre‐drying treatments. Convective drying at 60, 70, and 80°C, infrared drying and convective drying assisted with microwaves were applied to remove water from raw onion. Rehydration was done in water at room temperature and in boiling water. In general amount of absorbed water and increase in mass during rehydration, both were higher for pretreated material than those observed with dried raw onion. The mode of drying seemed to affect the course of rehydration of dried onion, and to improve its reconstitution properties. However, this was observed at room temperature rehydration only. Pre‐drying treatment followed by convection drying affected much stronger reconstitution properties of dried onion than the mode of drying. 相似文献
67.
A sonochemical technique is used for in situ coating of iron oxide (Fe3O4) nanoparticles on outer surface of MWCNTs. These Fe3O4/MWCNTs were characterized using a high‐resolution transmission electron microscope (HRTEM), X‐ray diffraction, and thermogravimetric analysis. The as‐prepared Fe3O4/MWCNTs composite nanoparticles were further used as reinforcing fillers in epoxy‐based resin (Epon‐828). The nanocomposites of epoxy were prepared by infusion of (0.5 and 1.0 wt %) pristine MWCNTs and Fe3O4/MWCNTs composite nanoparticles. For comparison purposes, the neat epoxy resin was also prepared in the same procedure as the nanocomposites, only without nanoparticles. The thermal, mechanical, and morphological tests were carried out for neat and nanocomposites. The compression test results show that the highest improvements in compressive modulus (38%) and strength (8%) were observed for 0.5 wt % loading of Fe3O4/MWCNTs. HRTEM results show the uniform dispersion of Fe3O4/MWCNTs nanoparticles in epoxy when compared with the dispersion of MWCNTs. These Fe3O4/MWCNTs nanoparticles‐infused epoxy nanocomposite shows an increase in glass transition (Tg) temperature. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
68.
Melt blending of aliphatic polyamides (PA6, PA66, PA12) with epoxidized and nonepoxidized elastomers (SBS, BS, PB) was investigated. IR and rheological studies have shown that epoxidized elastomers can simultaneously react both with polyamides and within their own phases during melt blending. Relative intensity of both processes is the main factor, which determines structure and properties of blends. SEM observations indicated that use of epoxidized elastomers improves blend homogeneity and decreases mean size of dispersed elastomer phase in comparison with nonepoxidized elastomers. Mechanical properties of epoxidized elastomers based blends are generally better with respect to similar blends with nonepoxidized elastomers. They depend on blend composition and type of polyamide and elastomer. Elastomer addition decreases tensile strength of all systems but in some cases, a considerable rise of impact strength was measured. Epoxidized SBS block copolymer was found to be the most effective modifier, especially with respect to PA6 and PA12. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
69.
Comments on S. Scarr's (see record 1997-38813-002) review of child day care. The authors note that the article raises issues of whether high-quality child care is associated with child outcomes and whether a decision needs to be made between high-quality and affordable child care. The authors argue that Scarr fails to put issues of affordability & quality in a comprehensive framework. They discuss the importance of quality child care, the cost of quality child care, and the complexity of issues in quality child care. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Wanda M. Aylward 《Electrochimica acta》2007,52(21):6275-6281
Composite films of polypyrrole with a sulphonated organically modified silica (ormosil) have been prepared on electrodes by the electrochemical oxidation of pyrrole in a liquid sol-gel electrolyte. The ormosil is incorporated into the polypyrrole matrix as an immobile polymeric counterion in addition to mobile Cl− counterions from the sol-gel electrolyte. Ion transport in the composites was investigated by impedance spectroscopy and electron microprobe analysis. The presence of both mobile and immobile counterions allows potential control of the mode of ion transport, with anion transport dominating at high potentials and cation transport dominating at low potentials. As the polymer is un-doped (reduced), its ionic conductivity first decreases as mobile anions are expelled, and then increases as cations and excess electrolyte are incorporated. 相似文献