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排序方式: 共有3741条查询结果,搜索用时 15 毫秒
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Dr. Elena Marchesi Dr. Nicola Chinaglia Dr. Massimo L. Capobianco Dr. Paolo Marchetti Tzu-En Huang Hao-Cheng Weng Dr. Jih-Hwa Guh Dr. Lih-Ching Hsu Dr. Daniela Perrone Dr. Maria Luisa Navacchia 《ChemMedChem》2019,14(7):779-787
A series of hybrid compounds based on natural products—bile acids and dihydroartemisinin—were prepared by different synthetic methodologies and investigated for their in vitro biological activity against HL-60 leukemia and HepG2 hepatocellular carcinoma cell lines. Most of these hybrids presented significantly improved antiproliferative activities with respect to dihydroartemisinin and the parent bile acid. The two most potent hybrids of the series exhibited a 10.5- and 15.4-fold increase in cytotoxic activity respect to dihydroartemisinin alone in HL-60 and HepG2 cells, respectively. Strong evidence that an ursodeoxycholic acid hybrid induced apoptosis was obtained by flow cytometric analysis and western blot analysis. 相似文献
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Pasquale Stano Tereza Pereira de Souza Paolo Carrara Emiliano Altamura Erica D’Aguanno Margherita Caputo 《先进材料力学与结构力学》2015,22(9):748-759
Here we report some recent biophysical issues on the preparation of solute-filled lipid vesicles and their relevance to the construction of “synthetic cells.” First, we introduce the “semi-synthetic minimal cells” as the liposome-based cell-like systems, which contain a minimal number of biomolecules required to display simple and complex biological functions. Next, we focus on recent aspects related to the construction of synthetic cells. Emphasis is given to the interplay between the methods of synthetic cell preparation and the physics of solute encapsulation. We briefly introduce the notion of structural and compositional “diversity” in synthetic cell populations. 相似文献
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Cecilia P. Chung Joseph F. Solus Annette Oeser Chun Li Paolo Raggi Jeffrey R. Smith C. Michael Stein 《International journal of molecular sciences》2015,16(2):3885-3894
Objective: Patients with rheumatoid arthritis (RA) have accelerated atherosclerosis, but there is limited information about the genetic contribution to atherosclerosis in this population. Therefore, we examined the association between selected genetic polymorphisms and coronary atherosclerosis in patients with RA. Methods: Genotypes for single-nucleotide polymorphisms (SNPs) in 152 candidate genes linked with autoimmune or cardiovascular risk were measured in 140 patients with RA. The association between the presence of coronary artery calcium (CAC) and SNP allele frequency was assessed by logistic regression with adjustment for age, sex, and race. To adjust for multiple comparisons, a false discovery rate (FDR) threshold was set at 20%. Results: Patients with RA were 54 ± 11 years old and predominantly Caucasian (89%) and female (69%). CAC was present in 70 patients (50%). A variant in rs2073618 that encodes an Asn3Lys missense substitution in the osteoprotegerin gene (OPG, TNFRSF11B) was significantly associated with the presence of CAC (OR = 4.09, p < 0.00026) and withstands FDR correction. Conclusion: Our results suggest that a polymorphism of the TNFRSF11B gene, which encodes osteoprotegerin, is associated with the presence of coronary atherosclerosis in patients with RA. Replication of this finding in independent validation cohorts will be of interest. 相似文献
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Paolo Giudici Iman Abu Hashish 《Quality and Reliability Engineering International》2020,36(6):2057-2065
The objective of this work is to understand the dynamics of cryptocurrency prices. Specifically, how prices switch between different regimes, going from “bull” to “stable” and “bear” times. For this purpose, we propose a hidden Markov model that aims at explaining the evolution of Bitcoin prices through different, unobserved states. The implementation of the proposed model includes a likelihood ratio test that allows to compare models with different states and with different covariance structures. Our empirical findings show that the time movements of Bitcoin prices across different exchange markets are well-described by the proposed model. In particular, a parsimonious model with a diagonal covariance matrix leads to better predictions, compared with a model with a full covariance matrix. 相似文献
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Raffaele Romano Alessandra Aiello Fabiana Pizzolongo Andrea Rispoli Lucia De Luca Paolo Masi 《International Journal of Food Science & Technology》2020,55(10):3334-3342
Tomato waste is characterised by high amounts of bioactive compounds, such as carotenoids, polyphenols and essential fatty acids. In this work, oleoresins were produced from tomato waste (skins + seeds) and skins using carbon dioxide under liquid and supercritical conditions. The use of ethanol as a co-solvent was also evaluated. Compositions of the oleoresins were analysed and compared to oleoresin obtained by means of an organic solvent, which was used as the control. Oleoresin extraction from the waste by liquid and supercritical CO2 provided the highest yields (12.5%–12.9%). The extracts obtained from the skins with supercritical CO2 without ethanol had the highest content of α- and γ-tocopherols (80 and 575 mg/100 g oleoresin, respectively), while lycopene and β-carotene were found at 205 and 75 mg/100 g oleoresin, respectively. The highest quantity of polyphenols (9305 mg GAE/100 g oleoresin) was found in the oleoresin extracted from skin by supercritical CO2 with ethanol. All oleoresins were characterised by a high antioxidant activity, which improved with the synergy of carotenoids, tocopherols and polyphenols. 相似文献
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Raffaella Colombo Adele Papetti 《International Journal of Food Science & Technology》2019,54(4):943-951
Avocado industry produces enormous by-products and represents an important source of raw material in food and non-food applications. This review aims to focus the attention on the valorisation of avocado wastes recycling to produce different materials with important industrial and environmental impacts. In fact, peels and seeds can be reused in food and cosmetic fields due to the presence of bioactive ingredients such as polyphenols; thanks to their antioxidant and antinflammatory activities. In addition, both peels and seeds can be reused in the production of carbonaceous materials with important consequences for environmental pollution in the removal of contaminants from water. Interesting applications of avocado wastes in photocatalysis and biofuel production are also discussed. All the utilisations attest the great potential of recycling avocado by-products, a little known resource. 相似文献