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排序方式: 共有1310条查询结果,搜索用时 140 毫秒
991.
The prevalence of liver cancer is constantly rising, with increasing incidence and mortality in Europe and the USA in recent decades. Among the different subtypes of liver cancers, hepatocellular carcinoma (HCC) is the most commonly diagnosed liver cancer. Besides advances in diagnosis and promising results of pre-clinical studies, HCC remains a highly lethal disease. In many cases, HCC is an effect of chronic liver inflammation, which leads to the formation of a complex tumor microenvironment (TME) composed of immune and stromal cells. The TME of HCC patients is a challenge for therapies, as it is involved in metastasis and the development of resistance. However, given that the TME is an intricate system of immune and stromal cells interacting with cancer cells, new immune-based therapies are being developed to target the TME of HCC. Therefore, understanding the complexity of the TME in HCC will provide new possibilities to design novel and more effective immunotherapeutics and combinatorial therapies to overcome resistance to treatment. In this review, we describe the role of inflammation during the development and progression of HCC by focusing on TME. We also describe the most recent therapeutic advances for HCC and possible combinatorial treatment options.  相似文献   
992.
During soya seeds germination in FeSO4 solutions their phytoferritin content is multiplied. Prepared soybean sprouts have been proposed as a safe and easily available source of iron supplementation. The preparation was compared with FeSO4 and ferritin isolates, using rats with induced iron deficiency anaemia. After the end of the 2-week supplementation experiment, it was observed that no statistically significant differences in haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin, and mean corpuscular haemoglobin concentration existed between those animals supplemented with sprouts enriched in ferritin, ferritin isolate and FeSO4 and healthy animals forming the control group. Moreover, the examined preparation had a beneficial influence on the recreation of ferritin reserves in both the liver and the blood serum, and also did not induce negative alterations in general growth parameters of animals. Use of an easily obtainable ferritin iron source may be a profitable alternative in supplementation due to its wide availability and food preservative properties.  相似文献   
993.
The stationary lumped-cell model was developed and used to simulate the thermal characteristics of domestic biomass boiler with helically coiled tube heat excha...  相似文献   
994.
995.
The high stability and conductivity of 3,4-disubstituted polythiophenes such as poly(3,4-ethylenedioxythiophene) (PEDOT) make them attractive candidates for commercial applications. However, next-generation nanoelectronic devices require novel macromolecular strategies for the precise synthesis of advanced polymer structures as well as their arrangement. In this report, we present a synthetic route to make ladder-like polymer brushes with poly(3,4-propylenedioxythiophene) (PProDOT)-conjugated chains. The brushes were prepared via a self-templating surface-initiated technique (ST-SIP) that combines the surface-initiated atom transfer radical polymerization (SI-ATRP) of bifunctional ProDOT-based monomers and subsequent oxidative polymerization of the pendant ProDOT groups in the parent brushes. The brushes prepared in this way were characterized by grazing-angle FTIR, XPS spectroscopy, and AFM. Steady-state and time-resolved photoluminescence measurements were used to extract the information about the structure and effective conjugation length of PProDOT-based chains. Stability tests performed in ambient conditions and under exposure to standardized solar light revealed the remarkable stability of the obtained materials.  相似文献   
996.
The nickel alloys of the Inconel type (containing above 15wt% of chromium), used in many industrial applications including the manufacture of aircraft, chemistry, power generation, and material processing, have advantageous mechanical properties, high plasticity and good corrosion resistance, but their frictional wear resistance is poor. This drawback can be obviated by subjecting the alloys to various surface treatments.The paper describes the structure and properties of nitrided layers produced on the Inconel 625 nickel alloy (20wt%Cr, 10wt%Mo, 5wt%Fe, 1wt%Co, balance-Ni). It has been found that the diffusion-type chromium nitride layer produced on the alloy surface improves the hardness, frictional wear resistance, fatigue strength and corrosion resistance of the alloy. It was demonstrated that the nitriding process can be successfully used for prolonging the service life of the fiberizing disc intended for the fabrication of what is known as glass wool.  相似文献   
997.
Most glycosyltransferases show remarkable gross and fine substrate specificity, which is reflected in the old one enzyme-one linkage paradigm. While human Gb3/CD77 synthase is a glycosyltransferase that synthesizes the Galα1→4Gal moiety mainly on glycosphingolipids, its pigeon homolog prefers glycoproteins as acceptors. In this study, we characterized two Gb3/CD77 synthase paralogs found in pigeons (Columba livia). We evaluated their specificities in transfected human teratocarcinoma 2102Ep cells by flow cytofluorometry, Western blotting, high-performance thin-layer chromatography, mass spectrometry and metabolic labelling with 14C-galactose. We found that the previously described pigeon Gb3/CD77 synthase (called P) can use predominately glycoproteins as acceptors, while its paralog (called M), which we serendipitously discovered while conducting this study, efficiently synthesizes Galα1→4Gal caps on both glycoproteins and glycosphingolipids. These two paralogs may underlie the difference in expression profiles of Galα1→4Gal-terminated glycoconjugates between neoavians and mammals.  相似文献   
998.
In this study, the authors present a model of the inelastic impact of bodies that takes place during handling of unit loads (cubiform parcels). A modified non‐linear Kelvin model is proposed, in which the relationships between object strains and elastic and damping forces of the impact are represented by power functions. The results of analytical investigations on the proposed model were confirmed by experiments consisting in tests of free fall of the load on rigid ground and on elastic beam. The developed model allows the assessment of the influence of mechanical properties of loads and conveyor‐line deflection mechanisms as well as impact velocity, on the dynamic forces exerted on the manipulated objects during the impact. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
999.
MSQL: A Query Language for Database Mining   总被引:9,自引:1,他引:8  
The tremendous number of rules generated in the mining process makes it necessary for any good data mining system to provide for powerful query primitives to post-process the generated rulebase, as well as for performing selective, query based generation. In this paper, we present the design and compilation of MSQL, the rule query language developed as part of the Discovery Board system.  相似文献   
1000.
In this contribution, the effect of hydrogenation conditions atmosphere (temperature and time) on physicochemical properties and photocatalytic efficiency of graphitic carbon nitride (g-C3N4, gCN) was studied in great details. The changes in the morphology, chemical structure, optical and electrochemical properties were carefully investigated. Interestingly, the as-modified samples exhibited boosted photocatalytic degradation of Rhodamine B (RhB) with the assistance of visible light irradiation. Among modified gCN, the sample annealed at 500 °C for 4 h (500-4) in H2 atmosphere exhibited the highest photocatalytic activity—1.76 times higher compared to pristine gCN. Additionally, this sample presented high stability and durability after four cycles. It was noticed that treating gCN with hydrogen at elevated temperatures caused the creation of nitrogen vacancies on gCN surfaces acting as highly active sites enhancing the specific surface area and improving the mobility of photogenerated charge carriers leading to accelerating the photocatalytic activity. Therefore, it is believed that detailed optimization of thermal treatment in a hydrogen atmosphere is a facile approach to boost the photoactivity of gCN.  相似文献   
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