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21.
Alessandro Lucidi Danilo Buca Carlo Ronsini Sara Tinari Giuseppina Bologna Davide Buca Martina Leombroni Marco Liberati Francesco DAntonio Giovanni Scambia Paola Lanuti Marco Petrillo 《International journal of molecular sciences》2020,21(22)
Extracellular vesicles (EVs) are a heterogeneous group of cell-derived submicron vesicles released under physiological or pathological conditions. EVs mediate the cellular crosstalk, thus contributing to defining the tumor microenvironment, including in epithelial ovarian cancer (EOC). The available literature investigating the role of EVs in EOC has been reviewed following PRISMA guidelines, focusing on the role of EVs in early disease diagnosis, metastatic spread, and the development of chemoresistance in EOC. Data were identified from searches of Medline, Current Contents, PubMed, and from references in relevant articles from 2010 to 1 April 2020. The research yielded 194 results. Of these, a total of 36 papers, 9 reviews, and 27 original types of research were retained and analyzed. The literature findings demonstrate that a panel of EV-derived circulating miRNAs may be useful for early diagnosis of EOC. Furthermore, it appears clear that EVs are involved in mediating two crucial processes for metastatic and chemoresistance development: the epithelial–mesenchymal transition, and tumor escape from the immune system response. Further studies, more focused on in vivo evidence, are urgently needed to clarify the role of EV assessment in the clinical management of EOC patients. 相似文献
22.
Antonio Camarano Javier Narciso Donatella Giuranno 《Journal of the European Ceramic Society》2019,39(14):3959-3970
Reactivity between SiC and Ir as a function of SiC-crystallinity was investigated by diffusion bonding technique under a vacuum and over the temperature range of 1200–1450 °C. As reaction products, various Ir-silicides and free unreacted-C were detected. Reactivity is strongly affected by the temperature and SiC-crystallinity involving a series of interactions, from “no reaction” to “massive exothermic reactions”. In particular, interfacial phenomena are more pronounced by the presence of defects and grain boundaries.Solid state reactions result in formation of fine C-precipitates rearranged in a quasi-periodic microstructure. On the contrary, clustering of highly ordered C-precipitates (C-graphitized) occurs after “massive reactions” take place.A relationship between the degree of graphitization (from 1 to multi-layers of graphene), temperature and SiC crystallinity was found by Raman spectroscopy. 2D-layering phenomenon is enhanced in polycrystalline SiC at high temperature. 相似文献
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Enrique Alexandre Antonio Pena Manuel Sobreira 《IEEE transactions on information technology in biomedicine》2006,10(4):809-811
This paper discusses the convenience of using two-dimensional (2-D) coding techniques for the compression of electrocardiogram (ECG) signals. These signals present a very clear periodicity that can be exploited by the use of a 2-D time/frequency transform to decorrelate it as much as possible. A brief theoretical approach is given to justify the use of this technique, and a comparison is made between a 2-D and a one-dimensional (1-D) uniform quantization scenarios. The influence of the error as well as the frame size on the estimation of the fundamental period is studied. 相似文献
27.
Javier Ramírez Antonio García Uwe Meyer-Bäse Fred Taylor Antonio Lloris 《The Journal of VLSI Signal Processing》2003,33(1-2):171-190
Currently there are design barriers inhibiting the implementation of high-precision digital signal processing (DSP) objects with field programmable logic (FPL) devices. This paper explores overcoming these barriers by fusing together the popular distributed arithmetic (DA) method with the residue number system (RNS) for use in FPL-centric designs. The new design paradigm is studied in the context of a high-performance filter bank and a discrete wavelet transform (DWT). The proposed design paradigm is facilitated by a new RNS accumulator structure based on a carry save adder (CSA). The reported methodology also introduces a polyphase filter structure that results in a reduced look-up table (LUT) budget. The 2C-DA and RNS-DA are compared, in the context of a FPL implementation strategy, using a discrete wavelet transform (DWT) filter bank as a common design theme. The results show that the RNS-DA, compared to a traditional 2C-DA design, enjoys a performance advantage that increases with precision (wordlength). 相似文献
28.
Daniela M. Nevskaia Maria Luisa Rojas Cervantes Antonio Guerrero Ruíz Juan de Dios Lpez Gonzlez 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,63(3):249-256
Adsorption of Triton X-100 on various silica substrates has been investigated. A number of solids, including a natural quartz, this quartz washed with HCl acid and subsequently heated at 1273 K; two aerosils and one Kieselgel silicas were studied. These solids exhibit surface areas in the range of 5 to 430 m2 g?1. All the Triton adsorption isotherms display an S-shape at the adsorption temperatures studied (298 and 308 K). It has been found that the pretreatments of natural quartz (by water washing, impurities removed by acid and/or high temperature calcination) affect considerably the amounts of TX-100 adsorbed. Measurements of surface composition have been made by X-ray photoelectron spectroscopy (XPS) with particular emphasis on the presence of impurities and on the number of OH groups at the surface of the samples. The nature of the surface hydroxyl has also been studied by infrared spectroscopy. Furthermore, the specific number of hydroxyl groups on the surface of the silica samples has been determined by thermogravimetric analysis. Finally an attempt to correlate solid surface characteristics with adsorption isotherms has been developed. 相似文献
29.
This study, which is based on responses from over 300 individuals in England and Wales, explores how a willingness to use a water-recycling system of specific configuration varies against a number of factors which are linked to system design, system scale, system context, and water-conservation behaviour. Findings show that there is broad willingness to accept in-house water recycling provided that public health is not compromised. 相似文献
30.
Anguilla is a UK overseas (non-independent) territory in the Caribbean. It is a small middle-income island with a population of 13 000, and recent statistics indicate that it is more dependent on tourism than any other country or territory in the world. Rapid population growth and development have placed more emphasis on the need for human health and environmental protection. For the first time, a systematic water-quality monitoring programme has been developed, based on the realities of the local situation, e.g. low resource base, limited capabilities, dependence on household rainwater catchment, storage cisterns, and a poor water-supply network. Development of the programme incorporated the key themes of pragmatic, realistic, incremental, responsive, and consultative approaches. 相似文献