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排序方式: 共有690条查询结果,搜索用时 31 毫秒
31.
Jacek Kiezun Janusz Godlewski Bartlomiej E. Krazinski Zygmunt Kozielec Zbigniew Kmiec 《International journal of molecular sciences》2022,23(7)
Colorectal cancer (CRC) is the second most common cause of cancer in women and the third in men. The postoperative pathomorphological evaluation of patients with CRC is extremely important for future therapeutic decisions. Although our previous studies demonstrated high galanin (GAL) presence within tumor tissue and an elevated concentration of GAL in the serum of CRC patients, to date, there is a lack of data regarding GAL receptor (GalR) protein expression in CRC cells. Therefore, the aim of this study was to evaluate the presence of all three types of GalRs (GalR1, GalR2 and GalR3) within epithelial cells of the human colon and CRC tissue with the use of the immunohistochemical method and to correlate the results with the clinical-pathological data. We found stronger immunoreactivity of GalR1 and GalR3 in CRC cells compared to epithelial cells of the unchanged mucosa of the large intestine. No differences in the GalR2 protein immunoreactivity between the studied tissues were noted. We also found that the increased immunoexpression of the GalR3 in CRC tissue correlated with the better prognosis and longer survival (p < 0.0079) of CRC patients (n = 55). The obtained results suggest that GalR3 may play the role of a prognostic factor for CRC patients. Based on data from the TCGA-COAD project deposited in the GDC Data Portal, we also found that GalR mRNA in cancer samples and the adjacent normal tissue did not correlate with immunoexpression of the GalR proteins in CRC cells and epithelial cells of the unchanged mucosa. 相似文献
32.
Zbigniew Pietrasik Jagvinder S. Dhanda Phyllis J. Shand Ronald B. Pegg 《Journal of food science》2006,71(2):S110-S118
The combined effects of injection, packaging (modified atmosphere packaging [MAP] with 70% O2/ 30% CO2 and vacuum packaging [VP]), storage temperature (‐1 °C and +4 °C), and storage time on the color, microbial and oxidative stability of beef and bison longissimus lumborum (LL) steaks were investigated. Beef LL steaks in MAP retained their bright red color longer than bison steaks. Bison steaks developed higher 2‐Thiobarbituric acid reactive substances (TBARS) during storage, and this might have influenced the resulting rapid loss of redness from the bloomed meat. Storage at ‐1 °C in MAP provided greater color stability and a longer storage life for both meat species studied. Injection of salt/phosphate had a beneficial effect on the color stability of steaks during retail display; however, this positive effect was more pronounced for bison steaks compared with those of beef. Steaks stored overnight under MAP before retail display maintained the highest a* values for up to 5 d compared with those stored under vacuum. MAP‐OV steaks generally maintained the highest OMB content for up to 5 d during retail display compared with those stored under vacuum. Nevertheless, OMB levels were significantly (P < 0.05) lower in bison steaks compared with those of beef irrespective of packaging treatments. Injected steaks and those stored at ‐1 °C had significantly (P < 0.05) higher OMB levels compared with non‐injected counterparts and those stored at +4 °C, respectively. MAP is an excellent option for short‐term storage due to its positive effects on meat color, but for longer storage, VP may be necessary. Storing meat under vacuum and then placing it under MAP just before retail display might be another option to increase shelf life. 相似文献
33.
可信计算的产业趋势和研究 总被引:2,自引:0,他引:2
可信计算实验研究已经进行了30多年,特别是在航空、航天、金融、证券、交通等安全关键领域取得了令人瞩目的成就.为了从数量和质量两方面综述可信计算的发展和进一步推动可信计算的研究,文中分析了可信计算的产业趋势,包括:(1)差错源的变化;(2)复杂性的迅速增加;(3)计算设备总量的增加.针对每一种趋势,指出了那些可以应用于终端产品或实验性产品以及生产这些产品过程的研究技术.文中的研究给出一个框架,既能反映可信计算过去的研究情况,也指明了今后的研究需求. 相似文献
34.
Karolina Ossowska Agata Motyka-Pomagruk Natalia Kaczyska Agnieszka Kowalczyk Wojciech Sledz Ewa Lojkowska Zbigniew Kaczyski 《International journal of molecular sciences》2022,23(4)
Pectobacterium parmentieri is a pectinolytic plant pathogenic bacterium causing high economic losses of cultivated plants. The highly devastating potential of this phytopathogen results from the efficient production of plant cell wall-degrading enzymes, i.e., pectinases, cellulases and proteases, in addition to the impact of accessory virulence factors such as motility, siderophores, biofilm and lipopolysaccharide (LPS). LPS belongs to pathogen-associated molecular patterns (PAMPs) and plays an important role in plant colonization and interaction with the defense systems of the host. Therefore, we decided to investigate the heterogeneity of O-polysaccharides (OPS) of LPS of different strains of P. parmentieri, in search of an association between the selected genomic and phenotypic features of the strains that share an identical structure of the OPS molecule. In the current study, OPS were isolated from the LPS of two P. parmentieri strains obtained either in Finland in the 1980s (SCC3193) or in Poland in 2013 (IFB5432). The purified polysaccharides were analyzed by utilizing 1D and 2D NMR spectroscopy (1H, DQF-COSY, TOCSY, ROESY, HSQC, HSQC-TOCSY and HMBC) in addition to chemical methods. Sugar and methylation analyses of native polysaccharides, absolute configuration assignment of constituent monosaccharides and NMR spectroscopy data revealed that these two P. parmentieri strains isolated in different countries possess the same structure of OPS with a very rare residue of 5,7-diamino-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic acid (pseudaminic acid) substituted in the position C-8: →3)-β-d-Galf-(1→3)-α-d-Galp-(1→8)-β-Pse4Ac5Ac7Ac-(2→6)-α-d-Glcp-(1→6)-β-d-Glcp-(1→. The previous study indicated that three other P. parmentieri strains, namely IFB5427, IFB5408 and IFB5443, exhibit a different OPS molecule than SCC3193 and IFB5432. The conducted biodiversity-oriented assays revealed that the P. parmentieri IFB5427 and IFB5408 strains possessing the same OPS structure yielded the highest genome-wide similarity, according to average nucleotide identity analyses, in addition to the greatest ability to macerate chicory tissue among the studied P. parmentieri strains. The current research demonstrated a novel OPS structure, characteristic of at least two P. parmentieri strains (SCC3193 and IFB5432), and discussed the observed heterogenicity in the OPS of P. parmentieri in a broad genomic and phenotype-related context. 相似文献
35.
Dagmara Wojcik-Grzybek Magdalena Hubalewska-Mazgaj Marcin Surmiak Zbigniew Sliwowski Anna Dobrut Agata Mlodzinska Adrianna Wojcik Slawomir Kwiecien Marcin Magierowski Agnieszka Mazur-Bialy Jan Bilski Tomasz Brzozowski 《International journal of molecular sciences》2022,23(6)
Inflammatory bowel diseases (IBD) are commonly considered as Crohn’s disease and ulcerative colitis, but the possibility that the alterations in gut microbiota and oxidative stress may affect the course of experimental colitis in obese physically exercising mice treated with the intestinal alkaline phosphatase (IAP) has been little elucidated. Mice fed a high-fat-diet (HFD) or normal diet (ND) for 14 weeks were randomly assigned to exercise on spinning wheels (SW) for 7 weeks and treated with IAP followed by intrarectal administration of TNBS. The disease activity index (DAI), grip muscle strength test, oxidative stress biomarkers (MDA, SOD, GSH), DNA damage (8-OHdG), the plasma levels of cytokines IL-2, IL-6, IL-10, IL-12p70, IL-17a, TNF-α, MCP-1 and leptin were assessed, and the stool composition of the intestinal microbiota was determined by next generation sequencing (NGS). The TNBS-induced colitis was worsened in obese sedentary mice as manifested by severe colonic damage, an increase in DAI, oxidative stress biomarkers, DNA damage and decreased muscle strength. The longer running distance and weight loss was observed in mice given IAP or subjected to IAP + SW compared to sedentary ones. Less heterogeneous microbial composition was noticed in sedentary obese colitis mice and this effect disappeared in IAP + SW mice. Absence of Alistipes, lower proportion of Turicibacter, Proteobacteria and Faecalibacterium, an increase in Firmicutes and Clostridium, a decrease in oxidative stress biomarkers, 8-OHdG content and proinflammatory cytokines were observed in IAP + SW mice. IAP supplementation in combination with moderate physical activity attenuates the severity of murine colitis complicated by obesity through a mechanism involving the downregulation of the intestinal cytokine/chemokine network and oxidative stress, the modulation of the gut microbiota and an improvement of muscle strength. 相似文献
36.
Kasper T. Møller Mathias Jørgensen Jacob G. Andreasen Jørgen Skibsted Zbigniew Łodziana Yaroslav Filinchuk Torben R. Jensen 《International Journal of Hydrogen Energy》2018,43(1):311-321
A new potassium tetraamidoboranealuminate, K[Al(NH2BH3)4], has been synthesized by a mechanochemical reaction between KAlH4 and NH3BH3. The compound, K[Al(NH2BH3)4], crystallizes in a triclinic unit cell with space group symmetry P?1. The crystal structure consists of [K(NH2BH3)6]5? octahedra which facilitate the bridging between K+ in 1D chains, while also bridging K+ to Al3+ to connect the 1D chains in a 3D network. Thermal analysis reveals that K[Al(NH2BH3)4] decomposes in two exothermic steps at T ~ 94 and 138 °C and releases primarily hydrogen. The total gas release amounts to ~6.0 wt% H2. The decomposition products are investigated ex situ by powder X-ray diffraction, infrared spectroscopy, and 11B and 27Al NMR and identified as KBH4 and amorphous phases, possibly BN3, N2BH, and/or NBH2 whereas aluminum is found in four-, five-, and six-fold coordination. Unfortunately, the decomposed sample shows no hydrogen absorption at T = 260 °C and p(H2) = 110 bar. 相似文献
37.
Rafal M. Molak Krystian Paradowski Tomasz Brynk Lukasz Ciupinski Zbigniew Pakiela Krzysztof J. Kurzydlowski 《International Journal of Pressure Vessels and Piping》2009,86(1):43-47
The aim of this study was to measure the mechanical properties of weld material taken from a single weld bead laid down on a 316L steel plate. Due to the low available volume of weld material, microsamples with a total length of 5.5 mm were used. The Digital Image Correlation method (DIC), which enables measurement of mechanical properties of very small samples, was employed for the strain measurements in a uniaxial tensile test. Samples were cut out from three different zones of the specimen: plate, weld, and the heat affected zone. The material from heat affected zone showed the highest value of the Ultimate Tensile Strength (UTS) (580 ± 7 MPa) and yield strength (339 ± 6 MPa). Plate material had lower UTS (559 ± 5 MPa) and yield strength (304 ± 7 MPa). The lowest values of UTS (526 ± 6 MPa) and yield strength (291 ± 8 MPa) have been revealed for the weld. The values obtained for UTS, yield strength and elongation to failure for the plate material were compared with data obtained using standard test specimens. No significant differences between results obtained for the microsamples and standard samples have been found. 相似文献
38.
Zbigniew Hnatejko 《中国稀土学报(英文版)》2012,(6):552-558
New solid complexes of europium,uranyl and zinc ions with N-oxides of 4-chloro-2,6-dimethylpyridine,quinoline and 4-meth-oxyquinaldinic acid in presence different anions were obtained and characterized by elemental and TG analyses,IR and luminescence spectra. The compounds are crystalline,hydrated or anhydrous salts with colours typical of metal ions.Thermal studies showed that in hydrated salts lattice or coordination water molecules are present.A role of different anions in the formation of various types of the complexes is presented. 相似文献
39.
This article presents a method of filtering thermal images by means of approximation using cubic B-spline patch surfaces. Approximation uses chord length parameterization with non-uniform distribution of knots, depending on the change rate of pixel values in rows and columns of the image. Advantages of approximation with such parameterization are compared with popular uniform parameterization. Presented method is very versatile and can be used for example in 3D surface topography of objects tested with stereoscopic microscopes, in resolution change of arbitrary images or modeling processes depending on two parameters. Filtering results are presented using plugin for the Soft4Image program, which was designed to unify different digital signal processing algorithms. 相似文献
40.
Sometime Query Answering Systems (QAS) for a Distributed Autonomous Information System (DAIS) may fail by returning the empty set of objects as an answer for a query q. Systems in DAIS can be incomplete, have hierarchical attributes, and the semantics of attributes and their values may differ between sites.
Also, if there are no objects in S matching q, the query may fail when submitted to S. Alternatively, QAS for S may try to relax the query q as it was proposed in T. Gaasterland (IEEE Expert, 12(5), 1997, 48–59), P. Godfrey (International Journal of Cooperative Information Systems, 6(2), 1997, 95–149) and W. Chu et al. (Journal of Intelligent Information Systems, 6(2/3), 1996, 223–259). It means that q can be replaced by a new more general query. Clearly, the goal is to find possibly the smallest generalization of q which will not fail in S. Smaller generalizations guarantee higher confidence in objects returned by QAS. Such QAS is called cooperative (only one site is involved). Queries may also fail in S when some of the attributes listed in q are outside the domain of S. To resolve this type of queries, assuming that S is a part of DAIS, we may extract definitions of such attributes from information systems residing at some of the remote sites for S and next use them to approximate q in S. In order to do that successfully, we assume that all involved systems have to agree on the ontology of some of their common
attributes Z.W. Raś and A. Dardzińska (Information Systems International Journal, 29(1), 2004, 47–58; Proceedings of FQAS 2004 Conference, LNCS/LNAI No. 3055, 2004, pp. 125–136); Z.W. Raś and S. Joshi, Fundamenta Informaticae Journal, 30(3/4), 1997, 313–324. QAS based on the above strategy is called collaborative (minimum two sites are involved). Similarly, a query may fail in S when the granularity of an attribute used in q is finer than the granularity of the same attribute in S. This paper shows how to use collaboration and cooperation approach to solve failing queries in DAIS assuming that attributes are hierarchical. Some aspects of a collaboration strategy dealing with failing query problem for
non-hierarchical attributes have been presented in Z.W. Raś and A. Dardzińska (Information Systems International Journal, 29(1), 2004, 47–58; Proceedings of FQAS 2004 Conference, LNCS/LNAI No. 3055, 2004, pp. 125–136). 相似文献