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排序方式: 共有1172条查询结果,搜索用时 15 毫秒
41.
Edelio Taboada Patricio Fisher Rory Jara Elisa Zúñiga Manuel Gidekel Juan Carlos Cabrera Eduardo Pereira Ana Gutiérrez-Moraga Reynaldo Villalonga Gustavo Cabrera 《Food chemistry》2010
Cell walls polysaccharides from murta fruit (Ugni molinae Turcz), an endemic Chilean species with relevant food uses, were fractionated by water, ammonium oxalate, hot diluted HCl and cold diluted NaOH extractions. The polysaccharide fractions were analysed for monosaccharide composition and physicochemical properties. Pectic substances were found in all extracts, but mainly in the oxalate and acid soluble fractions, in which they appear as homogalacturonan polymers. Murta pectin was further extracted by hot diluted acid treatment using industrial conditions, yielding 30% by weight of dry fruit. The polymer showed similar composition and physicochemical properties to those of commercial citrus pectin, presenting a galacturonic acid content of 70.9% (w/w), a molecular weight of 597 kDa, and a methoxylation degree of 57%. The FT-IR spectrum of murta pectin suggests the presence of ferulic acid residues on its structure and the NMR analysis confirmed the structure of this polysaccharide. It is concluded that murta fruit can be considered as a valuable source of high quality pectin. 相似文献
42.
Anna Michelotti Marco de Scordilli Elisa Bertoli Elisa De Carlo Alessandro Del Conte Alessandra Bearz 《International journal of molecular sciences》2022,23(12)
Standard treatment for advanced non-small cell lung cancer (NSCLC) historically consisted of systemic cytotoxic chemotherapy until the early 2000s, when precision medicine led to a revolutionary change in the therapeutic scenario. The identification of oncogenic driver mutations in EGFR, ALK and ROS1 rearrangements identified a subset of patients who largely benefit from targeted agents. However, since the proportion of patients with druggable alterations represents a minority, the discovery of new potential driver mutations is still an urgent clinical need. We provide a comprehensive review of the emerging molecular targets in NSCLC and their applications in the advanced setting. 相似文献
43.
Elisa Di Fabio Antonia Iazzetti Alessio Incocciati Valentina Caseli Giancarlo Fabrizi Alberto Boffi Alessandra Bonamore Alberto Macone 《International journal of molecular sciences》2022,23(12)
Amine oxidases are enzymes belonging to the class of oxidoreductases that are widespread, from bacteria to humans. The amine oxidase from Lathyrus cicera has recently appeared in the landscape of biocatalysis, showing good potential in the green synthesis of aldehydes. This enzyme catalyzes the oxidative deamination of a wide range of primary amines into the corresponding aldehydes but its use as a biocatalyst is challenging due to the possible inactivation that might occur at high product concentrations. Here, we show that the enzyme’s performance can be greatly improved by immobilization on solid supports. The best results are achieved using amino-functionalized magnetic microparticles: the immobilized enzyme retains its activity, greatly improves its thermostability (4 h at 75 °C), and can be recycled up to 8 times with a set of aromatic ethylamines. After the last reaction cycle, the overall conversion is about 90% for all tested substrates, with an aldehyde production ranging between 100 and 270 mg depending on the substrate used. As a proof concept, one of the aldehydes thus produced was successfully used for the biomimetic synthesis of a non-natural benzylisoquinoline alkaloid. 相似文献
44.
Eva Giralt-Steinhauer Joan Jimnez-Balado Isabel Fernndez-Prez Lucía Rey lvarez Ana Rodríguez-Campello ngel Ois Elisa Cuadrado-Godia Jordi Jimnez-Conde Jaume Roquer 《International journal of molecular sciences》2022,23(12)
Intracerebral hemorrhage (ICH) is a complex and heterogeneous disease, and there is no effective treatment. Spontaneous ICH represents the final manifestation of different types of cerebral small vessel disease, usually categorized as: lobar (mostly related to cerebral amyloid angiopathy) and nonlobar (hypertension-related vasculopathy) ICH. Accurate phenotyping aims to reflect these biological differences in the underlying mechanisms and has been demonstrated to be crucial to the success of genetic studies in this field. This review summarizes how current knowledge on genetics and epigenetics of this devastating stroke subtype are contributing to improve the understanding of ICH pathophysiology and their potential role in developing therapeutic strategies. 相似文献
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Julio C. Albornoz David A. Landínez Téllez Jairo Roa-Rojas Julian A. Munévar Elisa Baggio-Saitovich 《Journal of Superconductivity and Novel Magnetism》2013,26(6):2313-2317
In this work, we report synthesis and characterization of the new La2SrCo2FeO9 triple perovskite material. The samples were produced by the solid-state reaction method. The analyses of the XRD patterns were made by Rietveld refinement through the GSAS code. The results reveal that the material crystallizes in an orthorhombic complex perovskite, space group Immm (#71) with lattice parameters a=5.4314(3) ?, b=5.4583(3) ? and c=7.7018(2) ?. SEM micrographs evidence a strongly diffused granular morphology with mean grain size of 2 μm and the EDX spectra show that the chemical composition of samples are in good agreement with the nominal values of the stoichiometric formula. 57Fe Mössbauer spectroscopy recorded at 300 K reveals two sites in concordance with the X-ray diffraction measurements, and its valence state is +3, as determined from the isomer shift found. At 4.2 K magnetic ordering with canting of the Fe moments is found. Measurements of the magnetization as a function of temperature permitted us to determine the ferromagnetic characteristic of material with an effective magnetic moment of 9.7μ B. 相似文献
48.
Finite element procedures for the analysis of composite structures under compressive loads (buckling and post-buckling) generally
are not deployed in books because they are still considered object of research whereas they are deemed as assessed by researchers
that focus their papers on restricted audience topics. Therefore, regarding these procedures, a gap exists in literature between
what researchers consider as well established and what has been already published. The aim of this paper is to contribute
to close this gap by providing an insight in linear and non-linear buckling analyses and in their use with composite structures.
Both modelling and analysis considerations are presented and discussed, focusing on what can be considered as best practice
when dealing with this kind of problems. Applications (to a stiffened panel and to a wing box) are provided for demonstrating
the effectiveness of the procedures presented. 相似文献
49.
Francieli Tiecher Denise Carpena Coitinho Dal Molin Márcia Elisa Boscato Gomes Nicole Pagan Hasparyk Paulo José Meleragno Monteiro 《Cement and Concrete Composites》2012,34(10):1130-1140
Mesostasis material present in the interstices of volcanic rocks is the main cause of the alkali-aggregate reaction (AAR) in concretes made with these rock aggregates. Mesostasis often is referred to as volcanic glass, because it has amorphous features when analyzed by optical microscopy. However, this study demonstrates that mesostasis in the interstitials of volcanic rocks most often consists of micro to cryptocrystalline mineral phases of quartz, feldspars, and clays. Mesostasis has been identified as having different characteristics, and, thus, this new characterization calls for a re-evaluation of their influence on the reactivity of the volcanic rocks. The main purpose of this study is to correlate the characteristics of mesostasis with the AAR in mortar bars containing basalts and rhyolites. 相似文献
50.
Vildes M. Scussel Daniel Manfio Geovana D. Savi Elisa H.S. Moecke 《Journal of food science》2014,79(7):H1443-H1453
In this article, tissue layers and cells characteristics of the Brazil nut (Bertholletia excelsa H.B.K.) shell (tegument), brown skin (testae), and edible part (cotyledons) were identified by stereoscopy (SM) and scanning electron microscopies (SEM). (a) The shell (a lignin rich, protective wall) varies in thickness throughout the nut structure and comprises different tissue types (total 3)/texture (hard/mid‐hard/soft), layers (2 to 5), colors (light to dark brown and white to cream), cell shape (amorphous/flattened on both surfaces; polygonal and cylindrical with thick, porous primary and secondary wall in cross‐section), and vascular distribution (helically and polyedrical thickened vessels at soft tissue and locule/channel structures). These variations are observed either in the shell faces, face corners, nut tips, or locule in testae. (b) The brown skin (shell nut part linked to both the shell and edible part) is made of flattened irregular‐shaped parenchymal cells distributed in several layers with more flexible fibrous, thinner wall tissue than shell. It has both rough and smooth shiny texture on the upper and lower surfaces, respectively. However, the nut (c) edible part, that is the nut storage tissue, shows several different tissue/cell layers starting from epidermis (double/triple cells sequence of round and palisade shapes) layer–the endosperm tissue. The parenchymal tissues show cells of irregular shape with small and larger sizes distributed in regular and randomly layers, respectively, separated by a short meristem tissue layer. The cortex cells increase in size as they approach the cotyledons junction. The Brazil nut part's tissue layers and cells were identified by the SM and SEM microscopy methods applied, which provides knowledge for further understanding of nut alterations that may occur either in the forest or during the factory processing. 相似文献