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排序方式: 共有851条查询结果,搜索用时 15 毫秒
91.
Maria Vliora Eleni Nintou Eleni Karligiotou Leonidas G. Ioannou Elisabetta Grillo Stefania Mitola Andreas D. Flouris 《International journal of molecular sciences》2022,23(17)
Cancer is a set of diseases characterized by several hallmark properties, such as increased angiogenesis, proliferation, invasion, and metastasis. The increased angiogenic activity constantly supplies the tumors with nutrients and a plethora of cytokines to ensure cell survival. Along these cytokines is a newly discovered protein, called irisin, which is released into the circulation after physical exercise. Irisin is the product of fibronectin type III domain-containing protein 5 (FNDC5) proteolytic cleavage. Recently it has been the topic of investigation in several types of cancer. In this study, we conducted a systematic review and meta-analysis to investigate its implication in different types of cancer. Our results suggest that irisin expression is decreased in cancer patients, thus it can be used as a valid biomarker for the diagnosis of several types of cancer. In addition, our results indicate that irisin may have an important role in tumor progression and metastasis since it is involved in multiple signaling pathways that promote cell proliferation and migration. 相似文献
92.
Maria Antonietta Grignano Stefania Bruno Simona Viglio Maria Antonietta Avanzini Marta Tapparo Marina Ramus Stefania Croce Chiara Valsecchi Eleonora Francesca Pattonieri Gabriele Ceccarelli Federica Manzoni Annalia Asti Carmelo Libetta Vincenzo Sepe Paolo Iadarola Marilena Gregorini Teresa Rampino 《International journal of molecular sciences》2022,23(18)
We propose a new organ-conditioning strategy based on mesenchymal stromal cell (MSCs)/extracellular vesicle (EVs) delivery during hypothermic perfusion. MSCs/EVs marker CD73 is present on renal proximal tubular cells, and it protects against renal ischemia-reperfusion injury by converting adenosine monophosphate into adenosine (ADO). In this study, after checking if CD73-silenced EVs (EVsi) would impact in vitro tubular-cell proliferation, we perfused kidneys of a rat model of donation after circulatory death, with Belzer solution (BS) alone, BS supplemented with MSCs, EVs, or EVsi. The ADO and ATP levels were measured in the effluents and tissues. Global renal ischemic damage score (GRS), and tubular cell proliferation index (IPT) were evaluated in the tissue. EVsi did not induce cell proliferation in vitro. Ex vivo kidneys perfused with BS or BS + EVsi showed the worst GRS and higher effluent ADO levels than the MSC- and EV-perfused kidneys. In the EV-perfused kidneys, the tissue and effluent ATP levels and IPT were the highest, but not if CD73 was silenced. Tissue ATP content was positively correlated with tissue ADO content and negatively correlated with effluent ADO level in all groups. In conclusion, kidney conditioning with EVs protects against ischemic damage by activating the CD73/ADO system. 相似文献
93.
94.
John Domingue Liliana Cabral Stefania Galizia Vlad Tanasescu Alessio Gugliotta Barry Norton Carlos Pedrinaci 《Journal of Web Semantics》2008,6(2):109-132
A factor limiting the take up of Web services is that all tasks associated with the creation of an application, for example, finding, composing, and resolving mismatches between Web services have to be carried out by a software developer. Semantic Web services is a combination of semantic Web and Web service technologies that promise to alleviate these problems. In this paper we describe IRS-III, a framework for creating and executing semantic Web services, which takes a semantic broker-based approach to mediating between service requesters and service providers. We describe the overall approach and the components of IRS-III from an ontological and architectural viewpoint. We then illustrate our approach through an application in the eGovernment domain. 相似文献
95.
A new short-path distillation system applied to the reduction of cholesterol in butter and lard 总被引:5,自引:0,他引:5
Armando Lanzani Paolo Bondioli Carlo Mariani Liliana Folegatti Stefania Venturini Enzo Fedeli Pierre Barreteau 《Journal of the American Oil Chemists' Society》1994,71(6):609-614
A molecular distillation plant, built particularly to increase the separation efficiency and to obtain safer working conditions,
was tested to remove cholesterol from anhydrous butter and lard. A preliminary experiment was carried out with butter to evaluate
the fractionation obtained at temperatures between 190 and 250°C and residual pressures between 10−3 and 10−4 torr. A second experiment was carried out at 185°C and at the maximum operational vacuum, evaluating the fractionation achieved
within a time scale between 30 and 180 min. Cholesterol was almost completely removed during the second hour with minimal
loss of low-molecular weight triglycerides. An experiment was carried out with lard at 250°C and maximum achievable operational
vacuum (10−4 Torr), lasting approximately 6 h, and cholesterol was removed almost completely during the second hour without significant
modifications in the triglyceride composition. This situation remained constant throughout the duration of the test. 相似文献
96.
Static analysis of a Bickford beam by means of the DQEM 总被引:4,自引:0,他引:4
Claudio Franciosi Stefania Tomasiello 《International Journal of Mechanical Sciences》2007,49(1):122-128
In this paper the recently proposed differential quadrature element method is employed in order to solve the equilibrium equations of a higher-order beam. A simple five-node element is introduced, in which the vertical displacement is approximated by a sixth-order polynomial, whereas the rotation is consistently approximated by a fourth-order polynomial, and the resulting weighting coefficient matrix is given. Moreover, a general procedure is outlined, for an N-node element, in which vertical displacements and rotations are given by polynomials of order N+1 and N-1, respectively. Numerical examples are aimed both at checking the convergence of the results for increasing values of the nodes, and at comparing the used cubic beam theory with the simpler, linear, Timoshenko theory. 相似文献
97.
Maurizio Penco Luciana Sartore Fabio Bignotti Stefania Della Sciucca Vittorio Ferrari Paolo Crescini Salvatore D'Antone 《应用聚合物科学杂志》2004,91(3):1816-1821
The aim of this work was the development of materials to be used in the field of gas sensing for the detection of organic vapors. Conductive sensors were prepared with carbon black filled blends of poly(vinyl chloride) and diol‐terminated poly(?‐caprolactone), an oligomeric plasticizer. For comparison, blends with di(2‐ethylhexyl)phthalate, a traditional low‐molecular‐weight plasticizer, were also prepared. All sensors were tested upon exposure to different organic vapors. In general, the plasticizer content affected the response rates of the sensors, and a linear variation of the relative resistance with the analyte concentration was observed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1816–1821, 2004 相似文献
98.
Alessandra Cirillo Stefania Del Gaudio Giovanni Di Bernardo Umberto Galderisi Antonino Cascino Marilena Cipollaro 《European Food Research and Technology》2009,228(6):875-881
Random amplified polymorphic DNA (RAPD) is an efficient tool to detect DNA polymorphisms and to distinguish different clones
and cultivars. We have applied the RAPD technique to distinguish, starting from a single rice seed, among some Italian rice
cultivars from market and from National Institute for research on food and nutrition, Italy. We also estimated the genomic
similarity among the rice cultivars object of this study taking advantage of the amplification patterns. Despite the low genomic
variability among Italian rice cultivars, RAPD technique allowed us to distinguish among them. This indicates that RAPD can
be used routinely to verify the identity of Italian rice cultivars in order to prevent fraudulent commercial activity. 相似文献
99.
Concetta Boniglia Brunella CarratùRaffaella Gargiulo Stefania GiammarioliMaurizio Mosca Elisabetta Sanzini 《Food chemistry》2009
The isoflavone content of 14 soy-based dietary supplements intended to help alleviate perimenopausal and menopausal symptoms on sale in Italy were analysed using HPLC with UV detection. The aim was to quantify soy isoflavones after hydrolysis as aglycones, which are the bioactive part of isoflavone molecules. In the examined products, the amounts of isoflavones were frequently expressed ambiguously, and none of the products stated whether the isoflavone content of the product was expressed as aglycones or as conjugates. Each product revealed a different aglycone concentration profile. These supplements have different “fingerprints”, probably due to different sources of raw materials and to methods used in processing and preparation of extracts. In more than half the supplements tested, the actual values contained were below those stated and below those expected to help alleviate perimenopausal and menopausal symptoms. 相似文献
100.
Cavazzini A Dondi F Marmai S Minghini E Massi A Villani C Rompietti R Gasparrini F 《Analytical chemistry》2005,77(10):3113-3122
The chromatographic behavior of a series of racemic benzodiazepines was evaluated under linear and nonlinear conditions on a new hybrid polymeric (DACH-ACR) chiral stationary phase (CSP). Differently substituted benzodiazepines were employed as probes to make hypotheses concerning possible molecular interaction mechanisms originating between target compounds and active sites on the CSP. Hydrogen bonds were found to be pivotal for chromatographic retention and chiral selectivity. The competitive effect from a mobile-phase (MP) modifier able to interact with the CSP through H-bonds was investigated. The performance of the polymeric DACH-ACR CSP for preparative purposes was also evaluated. The competitive adsorption isotherms of two benzodiazepines, lorazepam and temazepam, were measured at different MP compositions through the so-called inverse method. The adsorption data were fitted with a competitive bi-Langmuir adsorption isotherm. Enantiomeric separations under nonlinear conditions were modeled by using the equilibrium dispersive (ED) model of chromatography. Theoretical overloaded band profiles (obtained by solving the system of partial differential equations described by the ED model) matched, in a significantly accurate way, the profiles experimentally measured. 相似文献