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排序方式: 共有515条查询结果,搜索用时 15 毫秒
411.
Angela Polito Lorenzo Barnaba Donatella Ciarapica Elena Azzini 《International journal of molecular sciences》2022,23(10)
Osteosarcopenia (OS) is defined by the concurrent presence of osteopenia/osteoporosis and sarcopenia. The pathogenesis and etiology of OS involve genetic, biochemical, mechanical, and lifestyle factors. Moreover, an inadequate nutritional status, such as low intake of protein, vitamin D, and calcium, and a reduction in physical activity are key risk factors for OS. This review aims to increase knowledge about diagnosis, incidence, etiology, and treatment of OS through clinical studies that treat OS as a single disease. Clinical studies show the relationship between OS and the risk of frailty, falls, and fractures and some association with Non-communicable diseases (NCDs) pathologies such as diabetes, obesity, and cardiovascular disease. In some cases, the importance of deepening the related mechanisms is emphasized. Physical exercise with adequate nutrition and nutritional supplementations such as proteins, Vitamin D, or calcium, represent a significant strategy for breaking OS. In addition, pharmacological interventions may confer benefits on muscle and bone health. Both non-pharmacological and pharmacological interventions require additional randomized controlled trials (RCT) in humans to deepen the synergistic effect of exercise, nutritional interventions, and drug compounds in osteosarcopenia. 相似文献
412.
A fully integrated 40-Gb/s clock and data recovery IC with 1:4DEMUX in SiGe technology 总被引:1,自引:0,他引:1
Reinhold M. Dorschky C. Rose E. Pullela R. Mayer P. Kunz F. Baeyens Y. Link T. Mattia J.-P. 《Solid-State Circuits, IEEE Journal of》2001,36(12):1937-1945
In this paper, a fully integrated 40-Gb/s clock and data recovery (CDR) IC with additional 1:4 demultiplexer (DEMUX) functionality is presented. The IC is implemented in a state-of-the-art production SiGe process. Its phase-locked-loop-based architecture with bang-bang-type phase detector (PD) provides maximum robustness. To the authors' best knowledge, it is the first 40-Gb/s CDR IC fabricated in a SiGe heterojunction bipolar technology (HBT). The measurement results demonstrate an input sensitivity of 42-mV single-ended data input swing at a bit-error rate (BER) of 10-10. As demonstrated in optical transmission experiments with the IC embedded in a 40-Gb/s link, the CDR/DEMUX shows complete functionality as a single-chip-receiver IC. A BER of 10-10 requires an optical signal-to-noise ratio of 23.3 dB 相似文献
413.
Alfonso Ranalli Agostino Tombesi Maria Luisa Ferrante Gabriella De Mattia 《Journal of the science of food and agriculture》1998,77(3):359-367
During the ripening cycle of Frantoio and Leccino olive varieties, the respiration rate of drupes was measured, giving the respiratory curve of fruits. This curve, for both varieties, dropped to a minimum point towards the end of November (a few days earlier for the Leccino variety) followed by a rise up to a maximum. This phase of the ripening process of olives corresponds to the climacteric crisis of the fruits. In this period the oil extracted from drupes gave the best analytical characteristics and was rich in tocopherols, phenols and aromatic volatile substances, components closely related to the shelf-life and the organoleptic quality of the product. The climacteric phase of drupes therefore corresponds to the optimal ripening stage of fruits and the harvesting of olives should be carried out during this period, in order to obtain oils of elevated quality. The respiration rate of drupes is therefore proposed as a new ripening index for drupes. © 1998 SCI. 相似文献
414.
Anna Jaromin Beata Gryzo Marek Jamrozik Silvia Parapini Nicoletta Basilico Marek Cega Donatella Taramelli Agnieszka Zagrska 《International journal of molecular sciences》2021,22(24)
Malaria is still one of the most dangerous infectious diseases and the emergence of drug resistant parasites only worsens the situation. A series of new tetrahydro-β-carbolines were designed, synthesized by the Pictet–Spengler reaction, and characterized. Further, the compounds were screened for their in vitro antiplasmodial activity against chloroquine-sensitive (D10) and chloroquine-resistant (W2) strains of Plasmodium falciparum. Moreover, molecular modeling studies were performed to assess the potential action of the designed molecules and toxicity assays were conducted on the human microvascular endothelial (HMEC-1) cell line and human red blood cells. Our studies identified N-(3,3-dimethylbutyl)-1-octyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b] indole-3-carboxamide (7) (a mixture of diastereomers) as the most promising compound endowed with the highest antiplasmodial activity, highest selectivity, and lack of cytotoxicity. In silico simulations carried out for (1S,3R)-7 provided useful insights into its possible interactions with enzymes essential for parasite metabolism. Further studies are underway to develop the optimal nanosized lipid-based delivery system for this compound and to determine its precise mechanism of action. 相似文献
415.
Luciana Galetto Dimitrios E. Miliordos Mattia Pegoraro Dario Sacco Flavio Veratti Cristina Marzachì Domenico Bosco 《International journal of molecular sciences》2016,17(9)
Flavescence dorée (FD) is a threat for wine production in the vineyard landscape of Piemonte, Langhe-Roero and Monferrato, Italy. Spread of the disease is dependent on complex interactions between insect, plant and phytoplasma. In the Piemonte region, wine production is based on local cultivars. The role of six local grapevine varieties as a source of inoculum for the vector Scaphoideus titanus was investigated. FD phytoplasma (FDP) load was compared among red and white varieties with different susceptibility to FD. Laboratory-reared healthy S. titanus nymphs were caged for acquisition on infected plants to measure phytoplasma acquisition efficiency following feeding on different cultivars. FDP load for Arneis was significantly lower than for other varieties. Acquisition efficiency depended on grapevine variety and on FDP load in the source plants, and there was a positive interaction for acquisition between variety and phytoplasma load. S. titanus acquired FDP with high efficiency from the most susceptible varieties, suggesting that disease diffusion correlates more with vector acquisition efficiency than with FDP load in source grapevines. In conclusion, although acquisition efficiency depends on grapevine variety and on FDP load in the plant, even varieties supporting low FDP multiplication can be highly susceptible and good sources for vector infection, while poorly susceptible varieties may host high phytoplasma loads. 相似文献
416.
Elio Ziparo Simonetta Petrungaro Elettra Sara Marini Donatella Starace Silvia Conti Antonio Facchiano Antonio Filippini Claudia Giampietri 《International journal of molecular sciences》2013,14(6):12090-12106
The role of autophagy is known to be highly complex and context-dependent, leading to both cancer suppression and progression in several tumors including melanoma, breast and prostate cancer. In the present review, recent advances in an understanding of the involvement of autophagy in prostate cancer treatment are described. The regulatory effects of androgens on prostate cancer cell autophagy are particularly discussed in order to highlight the effects of autophagy modulation during androgen deprivation. A critical evaluation of the studies examined in the present review suggests the attractive possibility of autophagy inhibition combined with hormonal therapy as a promising approach for prostate cancer treatment. 相似文献
417.
Maria Giovanna Scioli Alessandra Bielli Pietro Gentile Donatella Mazzaglia Valerio Cervelli Augusto Orlandi 《International journal of molecular sciences》2014,15(4):6517-6526
There is considerable attention regarding the role of receptor signaling and downstream-regulated mediators in the homeostasis of adipocytes, but less information is available concerning adipose-derived stem cell (ASC) biology. Recent studies revealed that the pathways regulating ASC differentiation involve the activity of receptor tyrosine kinases (RTKs), including fibroblast growth factor, vascular endothelial growth factor, ErbB receptors and the downstream-regulated serine/threonine protein kinase B (Akt) and phosphatase and tensin homolog (PTEN) activity. RTKs are cell surface receptors that represent key regulators of cellular homeostasis but also play a critical role in the progression of cancer. Many of the metabolic effects and other consequences of activated RTKs are mediated by the modulation of Akt and extracellular signal-regulated protein kinases 1 (Erk-1) signaling. Akt activity sustains survival and the adipogenic differentiation of ASCs, whereas Erk-1 appears downregulated. The inhibition of FGFR-1, EGFR and ErbB2 reduced proliferation, but only FGFR-1 inihibition reduced Akt activity and adipogenesis. Adipogenesis and neovascularization are also chronologically and spatially coupled processes and RTK activation and downstream targets are also involved in ASC-mediated angiogenesis. The potentiality of ASCs and the possibility to modulate specific molecular pathways underlying ASC biological processes and, in particular, those shared with cancer cells, offer new exciting strategies in the field of regenerative medicine. 相似文献
418.
Francesca D'Acunzo Donatella Capitani Giancarlo Masci Cristina Cherubini Ornella Ursini 《Polymer》2013
The search for innovative and well-defined organic–inorganic hybrid materials demands that the interplay between polymerization reactions, chemical reactivity, and physical adsorption be fully understood. We examine the case study of the thermal polymerization of styrene in the presence of silica, and the effect of pre-irradiation of silica with γ-rays. The effect of adsorption of styrene-derived radical species on the silica support and polymerization conditions on free and grafted (unextractable) polystyrenes and on polymerization mechanism is discussed on the basis of previous literature findings and new data. Evidence is provided of silica derivatization with various species besides polystyrene (13C CPMAS NMR), including products from a β-scission of the adsorbed radical intermediates ensuing oxygen donation from the silica network. The polymerization mechanism can be cationic as well as radical, depending on reaction conditions, and the cationic route prevails in the grafting of polystyrene from silica, resulting in a bimodal molecular weight distribution. 相似文献
419.
Gabriele Carullo Umile Gianfranco Spizzirri Monica Montopoli Veronica Cocetta Biagio Armentano Mattia Tinazzi Fabio Sciubba Gianluca Giorgi Maria Enrica Di Cocco Torsten Bohn Francesca Aiello Donatella Restuccia 《International Journal of Food Science & Technology》2022,57(7):4086-4095
An innovative functional food with symbiotic and functional potential was produced by combining probiotic milk kefir, and white grape-seed pomace obtained by UAE (ultrasound-assisted extraction) rich in catechin and glycosylated flavonoids. The milk kefir was fortified by adding, after 24 h of fermentation, a polymer of inulin grafted with seed extract. The inulin/grape extract-enriched polymer showed a higher antioxidant profile (P < 0.05). Simulated in vitro digestion demonstrated that 50 g of the kefir product would result in the delivery of antioxidants equivalent to 300 mg of ascorbic acid. The integrity of the intestinal barrier functions was not compromised by kefir treatments (at 10 μg mL-1). 相似文献
420.
Andrea Zambotti Mattia Biesuz Renzo Campostrini Sara Maria Carturan Giorgio Speranza Riccardo Ceccato Francesco Parrino Gian Domenico Sorarù 《Ceramics International》2021,47(6):8035-8043
Ceramic aerogels possess intriguing thermophysical properties which make them excellent candidates for high temperature thermal insulators. However, their properties can degrade at high temperature because of crystallization phenomena or because of densification (causing a sensible reduction of their specific surface area and porosity).The polymer derived ceramic (PDC) route is a relatively new way of developing ceramic aerogels. Several aspects influence the properties of the final product when dealing with preceramic polymers, among them their chemical composition and molecular architecture.In this work, we investigated the possibility of producing aerogels belonging to the SiCN system from polysilazanes mixtures, namely perhydropolysilazane (PHPS) and a methyl/vinyl-containing polysilazane, namely Durazane 1800®, thus changing the C/Si ratio of the amorphous pyrolyzed products. It is shown that the chemical composition of the ceramic aerogel affects the main properties of the porous materials, such as thermal stability and specific surface area (SSA). Results show that the presence of carbon in the aerogels inhibits crystallization of Si3N4 up to 1600 °C in N2 and allows to maintain a SSA of ~90 m2/g up to this temperature. 相似文献