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81.
Wojciech Jó?wicki Anna A. Bro?yna Jerzy Siekiera Andrzej T. Slominski 《International journal of molecular sciences》2015,16(2):3783-3803
RCAS1 is a protein that participates in regulation of the tumor microenvironment and its immune responses, all in order to evade the immune system. The aim of this study was to analyze RCAS1 expression in urothelial bladder cancer cells (and in fibroblasts and macrophages of the tumor stroma) and its relationship with the histological pattern of malignancy. Eighty-three postcystectomy patients were enrolled. We analyzed the histological maturity (grade), progress (pT stage), tissue invasion type (TIT), nonclassic differentiation number (NDN), and the ability to metastasize (pN). The expression of RCAS1 protein was analyzed by immunohistochemistry. Indicators of histological malignancy were observed solely in association with the RCAS1 expression in cells in the border parts (BPs) of the tumor. Histological malignancy of the tumor, indicated by the pT and pN, and metastasis-free survival time, correlated significantly with RCAS1 expression in tumor neoplastic cells, whereas malignancy determined by grade, TIT, and NDN correlated with RCAS1 expression in fibroblasts and macrophages in the tumor microenvironment. These findings suggest that the increased RCAS1 expression depends on its cellular source and that RCAS1 expression itself is a component of various signaling pathways. The immune escape occurs within the tumor BPs, where the increase in the RCAS1 expression occurs within tumor cells and stromal cells in its microenvironment. We conclude that the histological pattern of tumor malignancy, indicated by grade, TIT, NDN, pT, and pN is a morphological indicator of immune escape. 相似文献
82.
Nafion‐115/aromatic poly(etherimide) with isopropylidene groups/imidazole membranes for polymer fuel cells 下载免费PDF全文
Agnieszka Iwan Marek Malinowski Andrzej Sikora Igor Tazbir Grzegorz Pasciak Eugenia Grabiec 《应用聚合物科学杂志》2015,132(34)
Proton exchange membrane fuel cells (PEMFCs) with Pt/C gas diffusion electrodes and graphite single‐serpentine monopolar plates were constructed based on an aromatic poly(etherimide) with isopropylidene groups (PI)/imidazole (Im) and a popular Nafion‐115 matrix. The electrochemical properties of PEMFCs were tested at 25 and 60°C. The maximum power density of 171 mW/cm2 and the maximum current density of 484 mA/cm2 were detected for Nafion‐115/PI membrane. For both constructed PEMFCs the efficiency at 0.6 V was found about 41%. Immersion of Nafion‐115 in PI or PI/Im increased the thermal stability and mechanical properties of membranes. Thermal, mechanical properties and morphology of membranes were characterized by TGA, and AFM techniques including force spectroscopy. Interactions between the components in composite membranes were established by FT‐IR. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42436. 相似文献
83.
84.
Maria Leżańska Andrzej Olejniczak Jerzy P. Łukaszewicz 《Journal of Porous Materials》2018,25(6):1633-1648
Nitrogen-containing mesoporous carbons with the use of colloidal silica spheres of (14 nm) and chitosan as a carbon precursor were obtained. A removal of such small template particles from carbonized silica–chitosan composite is difficult and HF with a minimum concentration of 15 wt% should be used. By varying the silica-to-chitosan ratio, the porous characteristic of products is controlled. The modification by ZnCl2 with a molar Zn-to-C (in chitosan mass) ratio of ‘6’ results in the development of microporosity; however it is accompanied by a significant reduction of mesopore volume (Vmes). The addition of ZnCl2 in a ratio of ‘5.25’ and pH adjustment to 5.8 increase the volumes of micropores, small mesopores, BET surface area to 1975 m2/g, and preserve Vmes of 4.15 cm3/g. The novelty of the presented strategy is the creation of microporosity in the hard-templated materials by incorporating ZnCl2 into the mixture of Ludox HS-40 template and chitosan precursor, as well as the investigation on how the pH of synthesis influences the final porosity. The pH of a silica–chitosan–zinc solution, equal to 3.9, provides some coordination of Zn2+ by –OH and –NH2 groups, whereas pH adjustment to 5.8 results in the precipitation of a new template—Zn(OH)2. 相似文献
85.
Dominik Mierzwa Justyna Szadzińska Andrzej Pawłowski Reihaneh Pashminehazar Abdolreza Kharaghani 《Drying Technology》2019,37(8):988-1001
This study was conducted to investigate the drying characteristics and quality of raspberries dried in non-stationary conditions. Seven drying programs were carried out, including convective (CV) drying as a reference. The non-stationary-hybrid programs were based on continuous CV drying with intermittent microwave and ultrasound assistance. The Midilli–Kucuk model was used successfully to describe the drying kinetics of raspberry fruits. The comparison between moisture ratio, drying rate, diffusion coefficient, energy consumption, and quality analysis, showed that non-stationary-hybrid drying improves process kinetics and results in less color change, higher anthocyanin retention, and better texture profile analysis characteristics with optimal energy usage than other methods. In addition, the physical and microstructural changes occurred during different drying processes were discussed. 相似文献
86.
87.
Mieczyslaw Korzynski Andrzej Pacana 《Journal of Materials Processing Technology》2010,210(9):1217-1223
The article presents the results of examining the centreless roller burnishing technology worked out by the authors. The structure and the construction details of a prototype device for the centreless burnishing of shafts were presented. The experiments were carried on using 41Cr4 steel workpieces. The effects of the workpiece hardness, the surface roughness before burnishing, the deformation multiplicity and the tool interference on the roughness and the geometric structure after burnishing were investigated. The significant influence of the above parameters was confirmed and described as a mathematical power model. It also showed a beneficial effect of centreless burnishing parameters on roughness and geometric structure of the surface. 相似文献
88.
Sodium, potassium and ammonium cis- and trans-(2-n-alkyl-1,3-dioxan-5-yl) sulfates 6–8 (alkyl: n-C9H19, 6a–8a, and n-C11H23, 6b–8b) were synthesized in a reaction of aliphatic aldehydes 1a,b with glycerol 2 followed by separation in high yields of individual geometric isomers of cis-and trans-2-n-alkyl-5-hydroxy-1,3-dioxanes, cis-3a,b and trans-3a,b, followed by sulfation with sulfur trioxide-pyridine complex, and finally neutralization with NaOH, KOH, and NH4OH, respectively. Physical data of the compounds and some surface properties of 2-n-nonyl derivatives, such as critical micelle concentration (CMC), effectiveness of aqueous surface tension reduction (ΠCMC), surface excess concentration ΓCMC, and the surface area demand per molecule (ACMC), were determined. It was shown that the surface activity of these compounds is influenced both by their geometric structure
and by the monovalent counter-ion. 相似文献
89.
Joanna Koralewska Krzysztof Piotrowski Boguslawa Wierzbowska Andrzej Matynia 《中国化学工程学报》2009,17(2):330-339
A laboratory-scale reaction-crystallization process of struvite synthesis from diluted water solution of Mg2+, and ions was studied. The research covered the tests of two original constructions of continuous jet-pump Draft Tube Magma (DTM)-type crystallizers with internal circulation of suspension (upward/downward). Interactions between constructional, hydrodynamic and kinetic factors were established and discussed. Nucleation and linear growth rates of struvite crystals were calculated on the basis of population density distribution. Kinetic model of idealized Mixed Suspension Mixed Product Removal (MSMPR) crystallizer considering the size-dependent growth mechanism was applied (Rojkowski hyperbolic equation). For comparison purposes the kinetic data corre-sponded to a simpler, continuous draft tube-type crystallizer equipped with propeller agitator were analyzed. It was concluded that crystal product of larger size was withdrawn from the jet-pump DTM crystallizer of the descending flow of suspension in a mixing chamber. 相似文献
90.
Bogusława Wierzbowska Krzysztof Piotrowski Joanna Koralewska Nina Hutnik Andrzej Matynia 《Korean Journal of Chemical Engineering》2009,26(1):175-181
The experimental data concerning kinetics of a continuous mass crystallization in L-sorbose - water system are presented and
discussed. Influences of L-sorbose concentration in a feeding solution and mean residence time of suspension in a working
volume of laboratory DT MSMPR crystallizer on the resulting crystal size distributions, thus on the nucleation and growth
kinetics, were determined. The kinetic parameter values were evaluated on the basis of size-independent growth (SIG) kinetic
model (McCabe’s ΔL law). It was observed that within the investigated range of crystallizer productivity (220–2,200 kg of
L-sorbose crystals m−3 h−1), a crystal product of mean size Lm from 0.22 to 0.28 mm and CV from 68.8 to 44.0% was withdrawn. The values of linear growth rate show increasing trend (from
6.6·10−8 to 7.6·10−8 m s−1) with the productivity enlargement (assuming constant residence time τ=900 s). Occurrence of secondary nucleation phenomena
within the circulated suspension, resulting from the crystals attrition and breakage was observed. The parameter values in
a design equation, matching linear growth rate and suspension density with nucleation rate were determined. 相似文献