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71.
Laura Yl‐Outinen Venla Harju Tiina Joki Janne T. Koivisto Jennika Karvinen Minna Kellomki Susanna Narkilahti 《Macromolecular bioscience》2019,19(7)
There is a clear need for novel in vitro models, especially for neuronal applications. Development of in vitro models is a multiparameter task consisting of cell‐, biomaterial‐, and environment‐related parameters. Here, three different human origin neuronal cell sources are studied and cultured in various hydrogel 3D scaffolds. For the efficient evaluation of complex results, an indexing method for data is developed and used in principal component analysis (PCA). It is found that no single hydrogel is superior to other hydrogels, and collagen I (Col1) and hyaluronan–poly(vinyl alcohol) (HA1‐PVA) gels are combined into an interpenetrating network (IPN) hydrogel. The IPN gel combines cell supportiveness of the collagen gel and stability of the HA1‐PVA gel. Moreover, cell adhesion is studied in particular and it is found that adhesion of neurons differs from that observed for fibroblasts. In conclusion, the HA1‐PVA‐col1 hydrogel is a suitable scaffold for neuronal cells and supports adhesion formation in 3D. 相似文献
72.
Simultaneous determination of antiviral drugs in chicken tissues by ultra high performance liquid chromatography with tandem mass spectrometry 下载免费PDF全文
ZhengCai Liu Fang Yang Minna Yao YongHui Lin ZhiJiao Su 《Journal of separation science》2015,38(10):1784-1793
An ultra high performance liquid chromatography with tandem mass spectrometry method was established for the rapid and simultaneous analysis of seven antiviral drugs, amantadine, rimantadine, memantine, moroxydine, imiquimod, oseltamivir, and acyclovir, in chicken liver, muscle, and egg. Homogenized samples were extracted with trichloroacetic acid and acetonitrile solutions and then purified by cation‐exchange solid‐phase extraction. The target drugs were analyzed by liquid chromatography with a UPLC BEH Amide column (2.1 mm × 100 mm, 1.7 μm) coupled with a tandem mass spectrometer operating in the positive multiple‐reaction mode. A perfectly linear relationship was obtained within the concentration ranges of 0.5–20 μg/L for acyclovir and 0.1–10 μg/L for the other six antiviral drugs. The average recoveries of the seven antiviral drugs using four addition levels in chicken liver, muscle, and eggs were 82.67–90.10, 82.30–92.27, and 81.98–93.77%, respectively, and the acceptable coefficients of variation were 5.18–9.88, 4.84–11.2, and 42.8–9.95%, respectively. The detection limits and detection capabilities of the analysis method for the seven antiviral drugs were in the ranges of 0.04–0.64 and 0.11–0.78 μg/kg, respectively. Additionally, an inter‐laboratory study among five laboratories further validated the method. 相似文献
73.
Phenolic prepreg waste as functional filler with antioxidant effect in polypropylene and polyamide-6
Milled phenol-formaldehyde glass-fibre scrap (prepreg) was mixed with polypropylene (PP) and polyamide-6 (PA6). The oxidation induction time (OIT) of PP/prepreg composite measured by both chemiluminescence (CL) and Differential Scanning Calorimetry (DSC) was significantly longer than the oxidation induction time of unstabilised base PP. In addition, mechanical testing showed that the prepreg filler stabilised both PP and PA6 towards oxidation during long-term accelerated ageing. Headspace-gas chromatography/mass spectrometry (HS-GC/MS) showed that PP/prepreg composites emit somewhat larger amounts of volatile compounds compared to the reference PP/glass fibre composites, while the amount of volatile components emitted from PA6/prepreg composites was similar to the reference PA6/glass fibre composites. The new prepreg composites could have potential in thermally demanding applications especially if a secondary phosphite stabiliser is added to further increase the oxidative stability through synergy effects. 相似文献
74.
714名0~6岁儿童头发中6种微量元素含量及水平分析 总被引:1,自引:0,他引:1
报道了南山区714名0~6岁儿童头发中锌、铜、铁、钙、镁和锰的含量,发锌79.88×10-6、发铜9.64×10-6、发铁31.36×10-6、发钙560.54×10-6、发镁为66.12×10-6、发锰为2.24×10-6,并对分析数据进行了医学统计分析,结果表明各年龄组间、性别间无显著性差异。 相似文献
75.
在文[1]和[2]中,各自得到了如下结果:一个循环布尔矩阵A是本原的当且仅当gcd(i2-i1,…,i1-i1,n)=1,其中A=Pi1十Pi2十…+Pi1,0≤i1<i2<…<i1≤n-1,P是对应于n阶循环置换(123…n)的置换矩阵.在本文中,先把此结果推广到群矩阵(一种循环矩阵的推广).其次,讨论群布尔矩阵的周期.给出了计算周期的算法,最后,探讨循环布尔矩阵A的使Am p=Am的最小正整数m. 相似文献
76.
Claudia Dell’Era Juha-Pekka PokkiPetri Uusi-Kyyny Minna PakkanenVille Alopaeus 《Fluid Phase Equilibria》2010
Isothermal vapour–liquid equilibrium was measured for the systems of diethyl sulphide + 1-butene, +cis-2-butene, and +2-methylpropene at 312.6 K, diethyl sulphide + n-butane was measured at 317.6 K, diethyl sulphide + trans-2-butene at 317.5 K, and diethyl sulphide + 2-methylpropane at 308.0 K. The pressure–temperature–total composition data were converted into pressure–temperature–liquid–vapour composition data using the method of Barker. Error estimates are provided for each variable. The isothermal parameters for the Wilson, NRTL and UNIQUAC activity coefficient models were regressed. The measurements were compared with the predictions by COSMO segment activity coefficient (COSMO-SAC) and UNIFAC. 相似文献
77.
78.
Several new symmetrical aromatic hydrocarbon bridged bipyridine ligands and their binuclear Ru (II) complexes have been designed, synthesized and characterized on the basis of 1H NMR, MS and HRMS. Their absorption and emission properties, electrochemical behaviors and electrochemical luminescence were investigated. All ruthenium complexes show characteristic MLCT absorption and similar redox potential. Among the three complexes reported, 4c has the best electrochemical luminescence property. 相似文献
79.
Sirkku E. Jäntti Minna Hartonen Mika Hilvo Heli Nygren Tuulia Hyötyläinen Raimo A. Ketola Risto Kostiainen 《Analytica chimica acta》2013
An ultra performance liquid chromatography–electrospray ionization-tandem mass spectrometry (UPLC–MS/MS) method was developed for the analysis of steroids and their glucuronides in urine samples. The method provides high sensitivity and fast analysis, as both steroids and their glucuronides can be analyzed directly without hydrolysis or complex sample preparation. The method was applied in profiling of targeted and nontargeted steroids and steroid glucuronides during pregnancy. The concentrations of 11 of 27 targeted steroids and steroid glucuronides and the concentrations of 25 nontargeted steroid glucuronides increased about 10–400 fold during the pregnancy. The concentrations of most of these 36 compounds began to increase in the first days of the pregnancy, increased gradually during the pregnancy, achieved a maximum in late pregnancy, and decreased sharply after delivery. Exceptionally, the concentrations of allopregnanolone and 17-hydroxypregnenolone started to increase later than those of the other steroids. Moreover, the concentrations of E2 glucuronides began to decrease one week before the delivery, in contrast to most of the steroids and steroid glucuronides, whose concentrations dropped sharply during the delivery. Concentrations of 34 compounds decreased noticeably when the subject was on sick leave owing a series of painful contractions. The results suggest that steroids and especially steroid glucuronides may provide a valuable diagnostic tool to follow the course of pregnancy. 相似文献
80.