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排序方式: 共有940条查询结果,搜索用时 31 毫秒
921.
Emilio Senesi Roberto Lo Scalzo Caterina Prinzivalli Armando Testoni 《Journal of the science of food and agriculture》2002,82(6):655-662
The quality parameter of muskmelon (Cucumis melo L var reticulatus Naud) is often identified with the sugar content, particularly sucrose. However, high soluble solids concentration at harvest does not always correspond with high overall fruit quality and should be used in conjunction with the evaluation of aroma. In order to find quality indices, correlations were checked between aroma compounds detected on the melon pulp by headspace gas chromatography and sensory evaluation. Eight cultivars of muskmelon were analysed for their aroma content and other quality parameters. Aroma compounds were mainly esters, while (Z)‐6‐nonenal and (E)‐6‐nonenol, characteristic of melon, were not detected with the technique used. The data were subjected to statistical analyses in order to find significant correlations. High values of correlation were not found between chromatographic and sensory data, but a high correlation was found between total aromas and ethyl esters, both data of analytical source. This fact means that ethyl esters could be very important compounds for melon flavour and could be considered as markers of a good‐quality aroma. © 2002 Society of Chemical Industry 相似文献
922.
Margaret Ottaviano Emilio Francesco Giunta Pasquale Rescigno Ricardo Pereira Mestre Laura Marandino Marianna Tortora Vittorio Riccio Sara Parola Milena Casula Panagiotis Paliogiannis Antonio Cossu Ursula Maria Vogl Davide Bosso Mario Rosanova Brunello Mazzola Bruno Daniele Giuseppe Palmieri Giovannella Palmieri 《International journal of molecular sciences》2021,22(13)
The cure rate of germ cell tumours (GCTs) has significantly increased from the late 1970s since the introduction of cisplatin-based therapy, which to date remains the milestone for GCTs treatment. The exquisite cisplatin sensitivity has been mainly explained by the over-expression in GCTs of wild-type TP53 protein and the lack of TP53 somatic mutations; however, several other mechanisms seem to be involved, many of which remain still elusive. The findings about the role of TP53 in platinum-sensitivity and resistance, as well as the reported evidence of second cancers (SCs) in GCT patients treated only with surgery, suggesting a spectrum of cancer predisposing syndromes, highlight the need for a deepened understanding of the role of TP53 in GCTs. In the following report we explore the complex role of TP53 in GCTs cisplatin-sensitivity and resistance mechanisms, passing through several recent genomic studies, as well as its role in GCT patients with SCs, going through our experience of Center of reference for both GCTs and cancer predisposing syndromes. 相似文献
923.
Francisco Corbera Rafael Asenjo Emilio Zapata 《International journal of parallel programming》2002,30(1):37-63
Automatic parallelization of codes with complex data structures is becoming very important. These complex, and often recursive, data structures are widely used in scientific computing. Shape analysis is one of the key steps in the automatic parallelization of such codes. In this paper we extend the Static Shape Graph (SSG) method to enable the successful and accurate detection of complex doubly-linked structures. We have also included an interprocedural analysis in our framework. These techniques have been implemented in a compiler, which has been validated for several C codes. In particular, we present the results the compiler achieves for the C sparse LU factorization algorithm and for a recursive code generating a tree data structure. The output SSG perfectly describes the complex data structure used in these codes. 相似文献
924.
925.
Rubn Lpez-Corts Laura Muinelo-Romay Almudena Fernndez-Briera Emilio Gil-Martín 《International journal of molecular sciences》2022,23(15)
The present study explored the impact of inhibiting α(1,6)fucosylation (core fucosylation) on the functional phenotype of a cellular model of colorectal cancer (CRC) malignization formed by the syngeneic SW480 and SW620 CRC lines. Expression of the FUT8 gene encoding α(1,6)fucosyltransferase was inhibited in tumor line SW480 by a combination of shRNA-based antisense knockdown and Lens culinaris agglutinin (LCA) selection. LCA-resistant clones were subsequently assayed in vitro for proliferation, migration, and adhesion. The α(1,6)FT-inhibited SW480 cells showed enhanced proliferation in adherent conditions, unlike their α(1,6)FT-depleted SW620 counterparts, which displayed reduced proliferation. Under non-adherent conditions, α(1,6)FT-inhibited SW480 cells also showed greater growth capacity than their respective non-targeted control (NTC) cells. However, cell migration decreased in SW480 after FUT8 knockdown, while adhesion to EA.hy926 cells was significantly enhanced. The reported results indicate that the FUT8 knockdown strategy with subsequent selection for LCA-resistant clones was effective in greatly reducing α(1,6)FT expression in SW480 and SW620 CRC lines. In addition, α(1,6)FT impairment affected the proliferation, migration, and adhesion of α(1,6)FT-deficient clones SW480 and SW620 in a tumor stage-dependent manner, suggesting that core fucosylation has a dynamic role in the evolution of CRC. 相似文献
926.
Ekta Manocha Alessandra Consonni Fulvio Baggi Emilio Ciusani Valentina Cocce Francesca Paino Carlo Tremolada Arnaldo Caruso Giulio Alessandri 《International journal of molecular sciences》2022,23(10)
Pericytes (PCs) are mesenchymal stromal cells (MSCs) that function as support cells and play a role in tissue regeneration and, in particular, vascular homeostasis. PCs promote endothelial cells (ECs) survival which is critical for vessel stabilization, maturation, and remodeling. In this study, PCs were isolated from human micro-fragmented adipose tissue (MFAT) obtained from fat lipoaspirate and were characterized as NG2+/PDGFRβ+/CD105+ cells. Here, we tested the fat-derived PCs for the dispensability of the CD146 marker with the aim of better understanding the role of these PC subpopulations on angiogenesis. Cells from both CD146-positive (CD146+) and negative (CD146−) populations were observed to interact with human umbilical vein ECs (HUVECs). In addition, fat-derived PCs were able to induce angiogenesis of ECs in spheroids assay; and conditioned medium (CM) from both PCs and fat tissue itself led to the proliferation of ECs, thereby marking their role in angiogenesis stimulation. However, we found that CD146+ cells were more responsive to PDGF-BB-stimulated migration, adhesion, and angiogenic interaction with ECs, possibly owing to their higher expression of NCAM/CD56 than the corresponding CD146− subpopulation. We conclude that in fat tissue, CD146-expressing cells may represent a more mature pericyte subpopulation that may have higher efficacy in controlling and stimulating vascular regeneration and stabilization than their CD146-negative counterpart. 相似文献
927.
Estimating biomass carbon stocks for a Mediterranean forest in central Spain using LiDAR height and intensity data 总被引:7,自引:0,他引:7
Biomass fractions (total aboveground, branches and foliage) were estimated from a small footprint discrete-return LiDAR system in an unmanaged Mediterranean forest in central Spain. Several biomass estimation models based on LiDAR height, intensity or height combined with intensity data were explored. Raw intensity data were normalized to a standard range in order to remove the range dependence of the intensity signal. In general terms, intensity-based models provided more accurate predictions of the biomass fractions. Height models selected were mainly based on a percentile of the height distribution. Intensity models selected included variables that consider the percentage of the intensity accumulated at different height percentiles, which implicitly take into account the height distribution. The general models derived considering all species together were based on height combined with intensity data. These models yielded R2 values greater than 0.58 for the different biomass fractions considered and RMSE values of 28.89, 18.28 and 1.51 Mg ha−1 for aboveground, branch and foliage biomass, respectively. Results greatly improved for species-specific models using the main species present in each plot, with R2 values greater than 0.85, 0.70 and 0.90 for black pine, Spanish juniper and Holm oak, respectively, and with lower RMSE for the biomass fractions. Reductions in LiDAR point density had only a small effect on the results obtained, except for those models based on a variation of the Canopy Reflection Sum, which was weighted by the mean point density. Based on the species-specific equations derived, Holm oak dominated plots showed the highest average carbon contained by aboveground biomass and branch biomass 44.66 and 31.42 Mg ha− 1 respectively, while for foliage biomass carbon, Spanish juniper showed the highest average value (3.04 Mg ha− 1). 相似文献
928.
929.
Emilio Scalise Michel Houssa Geoffrey Pourtois Valery Afanas’ev André Stesmans 《Nano Research》2012,5(1):43-48
The electronic properties of two-dimensional honeycomb structures of molybdenum disulfide (MoS2) subjected to biaxial strain have been investigated using first-principles calculations based on density functional theory.
On applying compressive or tensile bi-axial strain on bi-layer and mono-layer MoS2, the electronic properties are predicted to change from semiconducting to metallic. These changes present very interesting
possibilities for engineering the electronic properties of two-dimensional structures of MoS2.
相似文献
930.
Cristina Ubeda María D. Vzquez-Carretero Andrea Luque-Tirado Rocío Ríos-Reina Ricardo Rubio-Snchez Emilio Franco-Macías Pablo García-Miranda María L. Calonge María J. Peral 《International journal of molecular sciences》2023,24(1)
Metabolites produced by an altered gut microbiota might mediate the effects in the brain. Among metabolites, the fecal volatile organic compounds (VOCs) are considered to be potential biomarkers. In this study, we examined both the VOCs and bacterial taxa in the feces from healthy subjects and Alzheimer’s disease (AD) patients at early and middle stages. Remarkably, 29 fecal VOCs and 13 bacterial genera were differentiated from the healthy subjects and the AD patients. In general, higher amounts of acids and esters were found in in the feces of the AD patients and terpenes, sulfur compounds and aldehydes in the healthy subjects. At the early stage of AD, the most relevant VOCs with a higher abundance were short-chain fatty acids and their producing bacteria, Faecalibacterium and Lachnoclostridium. Coinciding with the development of dementia in the AD patients, parallel rises of heptanoic acid and Peptococcus were observed. At a more advanced stage of AD, the microbiota and volatiles shifted towards a profile in the feces with increases in hexanoic acid, Ruminococcus and Blautia. The most remarkable VOCs that were associated with the healthy subjects were 4-ethyl-phenol and dodecanol, together with their possible producers Clostridium and Coprococcus. Our results revealed a VOCs and microbiota crosstalk in AD development and their profiles in the feces were specific depending on the stage of AD. Additionally, some of the most significant fecal VOCs identified in our study could be used as potential biomarkers for the initiation and progression of AD. 相似文献