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排序方式: 共有1479条查询结果,搜索用时 15 毫秒
71.
Maurizio Servili Maura Baldioli Roberto Selvaggini Enrico Miniati Alceo Macchioni Gianfrancesco Montedoro 《Journal of the American Oil Chemists' Society》1999,76(7):873-882
Phenolic compounds are the most important antioxidants of virgin olive oil. This paper reports on the application of solid
phase extraction (SPE) in the separation of phenolic compounds from olive fruit, olive oil, and by-products of the mechanical
extraction of the oil and the complete spectroscopic characterization by nuclear magnetic resonance of demethyloleuropein
and verbascoside extracted from olive fruit. SPE led to a higher recovery of phenolic compounds from olives than did liquid/liquid
extraction. SPE also was used to separate phenolic compounds from pomaces and vegetation waters. Phenylacid and phenyl-alcohol
concentrations in extracts obtained from SPE and liquid/liquid extraction were not significantly different (P<0.05). The recovery of the dialdehydic form of elenolic acid linked to 3,4-(dihydroxyphenyl)ethanol and an isomer of oleuropein
aglycon, however, was low. 相似文献
72.
The effectiveness of electrospinning as a simple approach to disperse POSS into a polymer matrix at a nm‐level has been assessed. Electrospun and cast films were prepared by dissolving CA and epoxycyclohexylisobutyl POSS in the solvent mixture acetone/DMAc. The membranes were characterized by SEM, TEM and WAXD. Whereas films produced by casting showed µm‐sized POSS crystals, thus suggesting a small affinity between the polymer matrix and the POSS molecules, those prepared by electrospinning were characterized by a nanometric POSS distribution. This is explained by considering the peculiar solvent evaporation mechanism, occurring during the electrospinning process, which allows to produce nanofibers characterized by a silsesquioxane dispersion similar to that present in solution.
73.
Enrico Lertora Carla Gambaro Chiara Mandolfino Matteo Pedemonte 《Welding International》2013,27(2):117-123
Current market demands drive companies to innovate their production techniques to improve products and simultaneously hold down costs. In the search for solutions aimed at an optimization of production processes, semi-finished products in aluminium alloys very definitely play a significant role. Moreover, the assembly of extruded parts with laminates may result in considerable difficulties, especially in relation to distortions or generated residual stress and process productivity. A solution to these issues may be found in the application of friction stir welding (FSW), characterized by low thermal input and high productivity. The asymmetry of the FSW process determines a different thermal input to the edges of the pieces to be joined. This aspect can be exploited when it is necessary to join pieces characterized by a very different thermal lag, as occurs in the case of joining extruded products and sheeting. This study aims to identify optimal FW parameters, placing particular attention on heat transferred to materials so as to provide an adequate thermal input that will allow for compensation of the different thermal capacity of the pieces in question. 相似文献
74.
Enrico Maccallini Theodoros Tsoufis Salvatore La Rosa Gennaro Chiarello Vincenzo Formoso Raffaele G. Agostino 《Carbon》2010,48(12):3434-3445
Fe-Co bimetallic catalysts supported on MgO were studied for the catalytic chemical vapor deposition growth of carbon nanotubes (CNTs). Different wt.% metal loadings were investigated at various deposition temperatures and times. Characterization of the products involved thermal analysis (DTA-TGA), X-ray diffraction, spectroscopy (Raman, UPS, EELS and STS) and microscopy (SEM, TEM and STM) techniques. It was found that the metal content is critical, not only to the yield and the structural quality of the synthesized carbon nanotubes, but it can be also used to tune the desired type of synthesized nanotubes. Lower (2 wt.%) loadings of Fe-Co catalysts favor the formation of single- and/or double-wall CNTs for deposition time and temperature 30 min and 800 °C, respectively. Thermal analysis and Raman measurements showed that these thin CNTs were synthesized at high amounts (CNT-per-catalyst wt.% of more than 100%), exhibiting high graphitization degree with only traces of by-products (mainly amorphous carbon) among them. Microscopy results revealed the formation of CNTs bundles, consisting of individual nanotubes with less than 2 nm outer diameter, while additional energy loss measurements pointed out that the deposited CNTs are mainly single wall. Higher (10 wt.%) Fe-Co loadings resulted to the formation of multi-wall CNTs. 相似文献
75.
In this paper, the exergetic analysis of a seawater membrane-based desalination plant has been carried out. The desalination plant has been described in detail, then the exergy of the various saline water streams has been determined and a comprehensive analysis towards the exergy distribution of the major process components has been conducted. The examination of the exergy losses throughout the plant revealed that exergy destruction was mainly due to pressure drops in the membrane modules, valves and brine lines. Moreover, 12.9% of the exergy input to the system was supplied by the heater. Therefore, the most reasonable way to reduce power input to the plant, thus improving its performance and cost, has been shown (i) to be replacing the valves on the reverse osmosis brine stream by an energy recovery system, and (ii) to have thermal energy available in the plant. With the identified technical changes, energy consumption decreased from 18.3 to 2.05 kWh/m3, resulting in an annual saving of 0.17$/m3. 相似文献
76.
Anna Galotta Enrico Giust Mauro Bortolotti Gian D. Sorarù Vincenzo M. Sglavo Mattia Biesuz 《Journal of the American Ceramic Society》2021,104(9):4329-4340
Diatomite, a natural silicate-based sedimentary rock, was densified by cold sintering at room temperature and 150°C under various pressures (100, 200, and 300 MPa) and using different NaOH water solutions (0–3 M). The relative density of cold sintered diatomite can be as high as 90%, a condition that can be achieved by conventional firing only at 1200–1300°C. The cold sintered materials maintain the same mineralogical composition of the starting powder (quartz, glass, and illite) and are constituted by well-deformed and flattened grains oriented orthogonally to the applied pressure. Conversely, an evident phase evolution takes place upon conventional firing with the formation of cristobalite and mullite. The bending strength of cold sintered artifacts can exceed 40 MPa and increases to ≈80 MPa after post-annealing at 800°C, such mechanical strength is much larger than that of conventionally pressed samples sintered at 800°C, which is only ≈1 MPa. 相似文献
77.
Thijs W. de Vos Dian Winkelhorst Hans J. Baelde Kyra L. Dijkstra Rianne D. M. van Bergen Lotte E. van der Meeren Peter G. J. Nikkels Leendert Porcelijn C. Ellen van der Schoot Gestur Vidarsson Michael Eikmans Rick Kapur Carin van der Keur Leendert A. Trouw Dick Oepkes Enrico Lopriore Marie-Louise P. van der Hoorn Manon Bos Masja de Haas 《International journal of molecular sciences》2021,22(13)
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a disease that causes thrombocytopenia and a risk of bleeding in the (unborn) child that result from maternal alloantibodies directed against fetal, paternally inherited, human platelet antigens (HPA). It is hypothesized that these alloantibodies can also bind to the placenta, causing placental damage. This study aims to explore signs of antibody-mediated placental damage in FNAIT. We performed a retrospective study that included pregnant women, their newborns, and placentas. It comprised 23 FNAIT cases, of which nine were newly diagnosed (14 samples) and 14 were antenatally treated with intravenous immune globulins (IVIg) (21 samples), and 20 controls, of which 10 had anti-HLA-class I antibodies. Clinical information was collected from medical records. Placental samples were stained for complement activation markers (C1q, C4d, SC5b-9, and mannose-binding lectin) using immunohistochemistry. Histopathology was examined according to the Amsterdam criteria. A higher degree of C4d deposition was present in the newly diagnosed FNAIT cases (10/14 samples), as compared to the IVIg-treated FNAIT cases (2/21 samples, p = 0.002) and anti-HLA-negative controls (3/20 samples, p = 0.006). A histopathological examination showed delayed maturation in four (44%) placentas in the newly diagnosed FNAIT cases, five (36%) in the IVIg-treated FNAIT cases, and one in the controls (NS). C4d deposition at the syncytiotrophoblast was present in combination with low-grade villitis of unknown etiology in three newly diagnosed FNAIT cases that were born SGA. We conclude that a higher degree of classical pathway-induced complement activation is present in placentas from pregnancies with untreated FNAIT. This may affect placental function and fetal growth. 相似文献
78.
Chiara Guglielmi Rosa Scarpitta Gaetana Gambino Eleonora Conti Francesca Bell Mariella Tancredi Tiziana Cervelli Elisabetta Falaschi Cinzia Cosini Paolo Aretini Caterina Congregati Marco Marino Margherita Patruno Brunella Pilato Francesca Spina Luisa Balestrino Elena Tenedini Ileana Carnevali Laura Cortesi Enrico Tagliafico Maria Grazia Tibiletti Stefania Tommasi Matteo Ghilli Caterina Vivanet Alvaro Galli Maria Adelaide Caligo 《International journal of molecular sciences》2021,22(14)
With the progress of sequencing technologies, an ever-increasing number of variants of unknown functional and clinical significance (VUS) have been identified in both coding and non-coding regions of the main Breast Cancer (BC) predisposition genes. The aim of this study is to identify a mutational profile of coding and intron-exon junction regions of 12 moderate penetrance genes (ATM, BRIP1, CDH1, CHEK2, NBN, PALB2, PTEN, RAD50, RAD51C, RAD51D, STK11, TP53) in a cohort of 450 Italian patients with Hereditary Breast/Ovarian Cancer Syndrome, wild type for germline mutation in BRCA1/2 genes. The analysis was extended to 5′UTR and 3′UTR of all the genes listed above and to the BRCA1 and BRCA2 known regulatory regions in a subset of 120 patients. The screening was performed through NGS target resequencing on the Illumina platform MiSeq. 8.7% of the patients analyzed is carriers of class 5/4 coding variants in the ATM (3.6%), BRIP1 (1.6%), CHEK2 (1.8%), PALB2 (0.7%), RAD51C (0.4%), RAD51D (0.4%), and TP53 (0.2%) genes, while variants of uncertain pathological significance (VUSs)/class 3 were identified in 9.1% of the samples. In intron-exon junctions and in regulatory regions, variants were detected respectively in 5.1% and in 32.5% of the cases analyzed. The average age of disease onset of 44.4 in non-coding variant carriers is absolutely similar to the average age of disease onset in coding variant carriers for each proband’s group with the same cancer type. Furthermore, there is not a statistically significant difference in the proportion of cases with a tumor onset under age of 40 between the two groups, but the presence of multiple non-coding variants in the same patient may affect the aggressiveness of the tumor and it is worth underlining that 25% of patients with an aggressive tumor are carriers of a PTEN 3′UTR-variant. This data provides initial information on how important it might be to extend mutational screening to the regulatory regions in clinical practice. 相似文献
79.
Enrico Capuzzi Alice Caldiroli Martina Capellazzi Ilaria Tagliabue Matteo Marcatili Fabrizia Colmegna Massimo Clerici Massimiliano Buoli Antonios Dakanalis 《International journal of molecular sciences》2021,22(17)
Esketamine (ESK) has been approved as a rapid-acting intranasal treatment for treatment-resistant depression (TRD). Although existing studies have investigated the efficacy of ESK in the 4-week induction phase, our knowledge about long-term ESK efficacy remains poor. The aim of this systematic review was to summarize the available data on long-term ESK efficacy for TRD. A systematic search was performed including articles in English, up to 31 March 2021. The search found 7 relevant studies, involving 1024 adult TRD patients. Continuing treatment with ESK after the 4-week induction phase may be associated with stable efficacy in relapse prevention among TRD patients. Conversely, the long-term antidepressant effectiveness upon discontinuation of ESK might be limited, although data from three studies had a moderate to high risk of bias. Overall, the results on the effectiveness of this compound in the long term are mixed. According to our findings, ESK treatment should be continued following the induction phase to reach a stable efficacy in relapse prevention, while the long-term antidepressant and anti-suicidal effects of ESK after discontinuation are inconsistent. Currently, the level of proof of ESK efficacy in long-term TRD treatment remains low and more RCTs with larger sample sizes and active comparators are needed. 相似文献
80.
Fabio Forghieri Giovanni Riva Ivana Lagreca Patrizia Barozzi Francesca Bettelli Ambra Paolini Vincenzo Nasillo Beatrice Lusenti Valeria Pioli Davide Giusti Andrea Gilioli Corrado Colasante Laura Galassi Hillary Catellani Francesca Donatelli Annalisa Talami Rossana Maffei Silvia Martinelli Leonardo Potenza Roberto Marasca Enrico Tagliafico Rossella Manfredini Tommaso Trenti Patrizia Comoli Mario Luppi 《International journal of molecular sciences》2021,22(17)
The C-terminal aminoacidic sequence from NPM1-mutated protein, absent in normal human tissues, may serve as a leukemia-specific antigen and can be considered an ideal target for NPM1-mutated acute myeloid leukemia (AML) immunotherapy. Different in silico instruments and in vitro/ex vivo immunological platforms have identified the most immunogenic epitopes from NPM1-mutated protein. Spontaneous development of endogenous NPM1-mutated-specific cytotoxic T cells has been observed in patients, potentially contributing to remission maintenance and prolonged survival. Genetically engineered T cells, namely CAR-T or TCR-transduced T cells, directed against NPM1-mutated peptides bound to HLA could prospectively represent a promising therapeutic approach. Although either adoptive or vaccine-based immunotherapies are unlikely to be highly effective in patients with full-blown leukemia, these strategies, potentially in combination with immune-checkpoint inhibitors, could be promising in maintaining remission or preemptively eradicating persistent measurable residual disease, mainly in patients ineligible for allogeneic hematopoietic stem cell transplant (HSCT). Alternatively, neoantigen-specific donor lymphocyte infusion derived from healthy donors and targeting NPM1-mutated protein to selectively elicit graft-versus-leukemia effect may represent an attractive option in subjects experiencing post-HSCT relapse. Future studies are warranted to further investigate dynamics of NPM1-mutated-specific immunity and explore whether novel individualized immunotherapies may have potential clinical utility in NPM1-mutated AML patients. 相似文献