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排序方式: 共有9786条查询结果,搜索用时 312 毫秒
1.
Rafael Salomão Mirian A. Kawamura Ana B.V. Emilio José Sakihama Ana M. Segadães 《Ceramics International》2021,47(11):15082-15093
Calcium hexaluminate (CA6) is an intrinsically densification-resistant material, therefore, its porous structures are key materials for applications as high-temperature thermal insulators. This article reports on the combination of calcined alumina and calcium aluminate cement (CAC) in castable aqueous suspensions for the in situ production of porous CA6. The CAC content (10–34 vol%) and the curing conditions ensure structural integrity prior to sintering and maximize the development of hydrated phases. Changes in physical properties, crystalline phases, and microstructure were investigated after isothermal treatments (120–1500 °C), and three sequential porogenic events were observed. The hydration of CAC preserved the water-derived pores (up to 120 °C), and the dehydroxylation of CAC hydrates (250–700 °C) generated inter-particles pores. Moreover, the in situ expansive formation of CA2 and CA6 (900–1500 °C) hindered densification and generated intra-particle pores. Such events differed from those observed with other CaO sources, and resulted in significantly higher pores content and lower thermal conductivity. 相似文献
2.
Victor H. Pino-Ramos Gerardo Cedillo Eduardo López-Barriguete Emilio Bucio 《应用聚合物科学杂志》2019,136(44):48170
Hydrophilic biocompatible surfaces can be obtained by grafting stimuli-sensitive polymers onto commercially available medical devices. Thermo and pH-responsive polymers are two of the most studied materials due to their potential application as drug delivery systems. Poly(N-vinylcaprolactam) has a lower critical solution temperature (LCST) near to physiological temperature. However, when it is grafted with pH-sensitive moieties its LCST it is affected undergoing remarkable displacements. We studied the effect of acrylic acid (AAc), 4-vinylpyridine (4VP), and 1-vinylimidazole (Vim) on the LCST of N-vinylcaprolactam (NVCL) grafted onto silicone rubber (SR), and SR-g-NVCL (32.5 °C). The binary graft copolymers were obtained by ionizing grafting radiation using the simultaneous technique; the samples were characterized by Fourier transform infrared attenuated total reflectance (FTIR-ATR), cross-polarization magic angle spinning nuclear magnetic resonance (CP/MAS 13C-NMR), and thermogravimetrical analysis (TGA). LCST value was dramatically affected by the comonomer content; even it was observed the switching from LCST to upper critical solution temperature (UCST) for (SR-g-NVCL)-g-AAc and (SR-g-NVCL)-g-4VP samples. The observed behavior is rarely reported for binary graft copolymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48170. 相似文献
3.
Italia Falcone Fabiana Conciatori Chiara Bazzichetto Emilio Bria Luisa Carbognin Paola Malaguti Gianluigi Ferretti Francesco Cognetti Michele Milella Ludovica Ciuffreda 《International journal of molecular sciences》2020,21(22)
Breast cancer was one of the first malignancies to benefit from targeted therapy, i.e., treatments directed against specific markers. Inhibitors against HER2 are a significant example and they improved the life expectancy of a large cohort of patients. Research on new biomarkers, therefore, is always current and important. AXL, a member of the TYRO-3, AXL and MER (TAM) subfamily, is, today, considered a predictive and prognostic biomarker in many tumor contexts, primarily breast cancer. Its oncogenic implications make it an ideal target for the development of new pharmacological agents; moreover, its recent role as immune-modulator makes AXL particularly attractive to researchers involved in the study of interactions between cancer and the tumor microenvironment (TME). All these peculiarities characterize AXL as compared to other members of the TAM family. In this review, we will illustrate the biological role played by AXL in breast tumor cells, highlighting its molecular and biological features, its involvement in tumor progression and its implication as a target in ongoing clinical trials. 相似文献
4.
Emilio Pradal-Velázquez Fan Yang Derek C. Sinclair 《Journal of the American Ceramic Society》2020,103(12):6801-6810
The compositional limits of a previously reported (J. Am. Ceram. Soc., 61, 5-8. (1978)) but relatively unstudied sodium-bismuth titanate pyrochlore solid solution are revised and their electrical properties presented. The pyrochlore solid solution we report forms via a different mechanism to that originally reported and occurs in a different location within the Na2O-Bi2O3-TiO2 ternary system. In both cases, relatively large amounts of vacancies are required on the A-sites and on the oxygen sites, similar to that reported for undoped ‘Bi2Ti2O7’ pyrochlore. In contrast to ‘Bi2Ti2O7’, this ternary pyrochlore solid solution can be prepared and ceramics sintered using conventional solid-state methods; however, the processing requires several challenges to be overcome to obtain dense ceramics. This cubic pyrochlore series has low electrical conductivity (and does not exhibit any evidence of oxide-ion conduction) and exhibits relaxor ferroelectric behavior with a broad permittivity maximum of ~100 near room temperature. Variable temperature neutron diffraction data do not provide any conclusive evidence for a phase transition in the pyrochlore solid solution between ~4 and 873 K. 相似文献
5.
Pablo Hernndez‐Alonso Nerea Becerra‐Toms Christopher Papandreou Mnica Bull Marta Guasch‐Ferr Estefanía Toledo Miguel Ruiz‐Canela Clary B. Clish Dolores Corella Courtney Dennis Amy Deik Dong D. Wang Cristina Razquin Jean‐Philippe Drouin‐Chartier Ramon Estruch Emilio Ros Montserrat Fit Fernando Ars Miquel Fiol Lluís Serra‐Majem Liming Liang Miguel A Martínez‐Gonzlez Frank B Hu Jordi Salas‐Salvad 《Molecular nutrition & food research》2020,64(12)
6.
Prof. Dr. Arun K. Ghosh Dr. Margherita Brindisi Dr. Yu-Chen Yen Emma K. Lendy Dr. Satish Kovela Emilio Leal Cárdenas Dr. Bhavanam Sekhara Reddy Dr. Kalapala Venketeswara Rao Deborah Downs Dr. Xiangping Huang Dr. Jordan Tang Prof. Dr. Andrew D. Mesecar 《ChemMedChem》2019,14(5):545-560
Herein we present the design, synthesis, and biological evaluation of potent and highly selective β-secretase 2 (memapsin 1, beta-site amyloid precursor protein cleaving enzyme 2, or BACE 2) inhibitors. BACE2 has been recognized as an exciting new target for type 2 diabetes. The X-ray structure of BACE1 bound to inhibitor 2 a {N3-[(1S,2R)-1-benzyl-2-hydroxy-3-[[(1S,2S)-2-hydroxy-1-(isobutylcarbamoyl)propyl]amino]propyl]-5-[methyl(methylsulfonyl)amino]-N1-[(1R)-1-phenylpropyl]benzene-1,3-dicarboxamide} containing a hydroxyethylamine isostere was determined. Based on this structure, a computational docking study was performed which led to inhibitor 2 a -bound BACE2 models. These were used to optimize the potency and selectivity of inhibitors. A systematic structure–activity relationship study led to the identification of determinants of the inhibitors’ potency and selectivity toward the BACE2 enzyme. Inhibitors 2 d [N3-[(1S,2R)-1-benzyl-2-hydroxy-3-[[(1S,2S)-2-hydroxy-1-(isobutylcarbamoyl)pentyl]amino]propyl]-N1-methyl-N1-[(1R)-1-phenylpropyl]benzene-1,3-dicarboxamide; Ki=0.031 nm , selectivity over BACE1: ≈174 000-fold] and 3 l [N1-((2S,3R)-3-hydroxy-1-phenyl-4-((3-(trifluoromethyl)benzyl)amino)butan-2-yl)-N3,5-dimethyl-N3-((R)-1-phenylethyl)isophthalamide; Ki=1.6 nm , selectivity over BACE1: >500-fold] displayed outstanding potency and selectivity. Inhibitor 3 l is nonpeptide in nature and may pave the way to the development of a new class of potent and selective BACE2 inhibitors with clinical potential. 相似文献
7.
8.
Annamaria Perna Amalia Simonetti Vita Acquaviva Rocco Rossano Giulia Grassi Emilio Gambacorta 《International Journal of Food Science & Technology》2020,55(5):2020-2028
The aim of this study was to estimate the hydrolytic degree and antioxidant activity of purified casein characterised by different haplotypes (αs1-, β- and k-casein) after in vitro digestion with two different enzymatic systems: pepsin from porcine gastric mucosa (EP) and a crude enzymatic extract from the edible mushroom Pleurotus eryngii. The used enzymes showed a different mode of casein catalysis with a consequent production of peptides of different antioxidant activity. The CN haplotype significantly influenced peptides production; in fact, the amino acid substitutions caused by genetic polymorphisms at the αs1-, β- and k-CN loci influenced the sites of enzymatic cleavage and therefore the produced peptides. The above is evidenced by the different antioxidant activity found in the hydrolysates depending on the used enzymatic system, the CN haplotype, and the CN haplotype × enzymatic treatment interaction. The findings of this study are a perspective for the production of specific foods that exert a biological effect in addition to the nutritional one. 相似文献
9.
lvaro Hernez Albert Sanllorente Olga Castaer Miguel . Martínez‐Gonzlez Emilio Ros Xavier Pint Ramn Estruch Jordi Salas‐Salvad Dolores Corella ngel M. Alonso‐Gmez Lluis Serra‐Majem Miquel Fiol Jos Lapetra Enrique Gmez‐Gracia Rafael de la Torre Rosa‐María Lamuela‐Ravents Montserrat Fit 《Molecular nutrition & food research》2019,63(6)
10.
Pablo Hernndez‐Alonso Christopher Papandreou Mnica Bull Miguel Ruiz‐Canela Courtney Dennis Amy Deik Dong D. Wang Marta Guasch‐Ferr Edward Yu Estefanía Toledo Cristina Razquin Dolores Corella Ramon Estruch Emilio Ros Montserrat Fit Fernando Ars Miquel Fiol Lluís Serra‐Majem Liming Liang Clary B. Clish Miguel A Martínez‐Gonzlez Frank B Hu Jordi Salas‐Salvad 《Molecular nutrition & food research》2019,63(17)