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1.
Valentina Masola Gianluigi Zaza Arduino Arduini Maurizio Onisto Giovanni Gambaro 《International journal of molecular sciences》2021,22(6)
The endothelial glycocalyx, the gel layer covering the endothelium, is composed of glycosaminoglycans, proteoglycans, and adsorbed plasma proteins. This structure modulates vessels’ mechanotransduction, vascular permeability, and leukocyte adhesion. Thus, it regulates several physiological and pathological events. In the present review, we described the mechanisms that disturb glycocalyx stability such as reactive oxygen species, matrix metalloproteinases, and heparanase. We then focused our attention on the role of glycocalyx degradation in the induction of profibrotic events and on the possible pharmacological strategies to preserve this delicate structure. 相似文献
2.
Gina Cavaliere Giovanna Trinchese Nadia Musco Federico Infascelli Chiara De Filippo Vincenzo Mastellone Valeria Maria Morittu Pietro Lombardi Raffaella Tudisco Micaela Grossi Vincenzo Monda Monica I. Cutrignelli Antonietta Messina Serena Calabrò Heleena B. Moni Luigi Stradella Giovanni Messina Marcellino Monda Maria Pina Mollica 《Journal of dairy science》2018,101(3):1843-1851
Excessive energy intake may evoke complex biochemical processes characterized by inflammation, oxidative stress, and impairment of mitochondrial function that represent the main factors underlying noncommunicable diseases. Because cow milk is widely used for human nutrition and in food industry processing, the nutritional quality of milk is of special interest with respect to human health. In our study, we analyzed milk produced by dairy cows fed a diet characterized by a high forage:concentrate ratio (high forage milk, HFM). In view of the low n-6:n-3 ratio and high content of conjugated linoleic acid of HFM, we studied the effects of this milk on lipid metabolism, inflammation, mitochondrial function, and oxidative stress in a rat model. To this end, we supplemented for 4 wk the diet of male Wistar rats with HFM and with an isocaloric amount (82 kJ, 22 mL/d) of milk obtained from cows fed a diet with low forage:concentrate ratio, and analyzed the metabolic parameters of the animals. Our results indicate that HFM may positively affect lipid metabolism, leptin:adiponectin ratio, inflammation, mitochondrial function, and oxidative stress, providing the first evidence of the beneficial effects of HFM on rat metabolism. 相似文献
3.
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
4.
5.
Scheduling Algorithms for Packet-Oriented MAC Protocols in Wireless Multimedia Systems 总被引:1,自引:1,他引:0
Romano Fantacci Giovanni Giambene Francesco Petiti 《Wireless Personal Communications》2003,24(3):363-388
Future generation wireless multimediacommunications will require efficient Medium AccessControl (MAC) protocols able to guarantee suitable Qualityof Service (QoS) levels for different traffic classes whileachieving a high utilization of radio resources. This paperproposes a new scheduling technique to be adopted at the MAClevel in wireless access systems, named Dynamic Scheduling-Time DivisionDuplexing (DS-TDD), that efficiently managesvideo, voice, Web and background traffics. A theoretical approachis proposed in this paper to evaluate the DS-TDD performance withvoice and Web traffics. Simulation results have permitted tohighlight the following promising characteristics of the DS-TDDscheme: (i) a high capacity of real-time traffics isattained with a QoS insensitive to Web and background trafficloads; (ii) a high throughput can be guaranteed whilepreserving the QoS levels of the different traffic classes;(iii) heavier downlink traffic loads do not modify the QoSof uplink traffics. Finally, extensive comparisons with differentscheduling schemes proposed in the literature have permitted tohighlight the better performanceof DS-TDD. 相似文献
6.
Adriana Brancaccio Giovanni Leone Rocco Pierri 《AEUE-International Journal of Electronics and Communications》2004,58(6):382-390
In this paper, by applying a non linear model for the electromagnetic inverse scattering, a technique for the dielectric profiling of a planarly layered medium is investigated and applied to void localization and diagnostics inside a homogeneous lossless slab (one-dimensional geometry). Data are collected under plane wave multifrequency normal incidence. Suitable finite dimensional representations for the unknown functions are introduced and their influence on the model is discussed. The resulting functional equation is solved by the method of weighted residuals and the solution algorithm amounts to minimizing a non quadratic function, where particular attention is devoted to reduce the occurrence of local minima. Finally, the inversion algorithm is validated by applications to both simulated and experimental data. 相似文献
7.
QoS assessment of 3G video-phone calls by tracing watermarking exploiting the new colour space `YST?
Tracing watermarking has been recently proposed as a technique to provide a blind measure of the quality of service of the communication link, focusing on multimedia communication scenarios. 3G communication scenarios, where each customer transmits both voice and MPEG-4 video sequences in real time, have been considered. Typical video-phone call consists of close shots of speakers, framing their face in the foreground. For such particular application, a novel colour space (YST) is adopted to minimise the perceptual distortions on face coding introduced by watermarking. In the YST space, the luminance component (Y) is the same as in conventional YUV space, whereas the vectors S and T lie within the chrominance (UV) plane. The S (skin) component is a linear combination of U and V obtained as the 'average' chrominance estimated from an assorted set human faces to achieve a reasonable generalisation. The third component, T, is defined as orthogonal to the YS plane. The results show the benefits obtained in digital watermarking by the new representation against the conventional approach. In fact, the sensitivity of the YST representation outperforms the conventional one in terms of objective (mean square error, peak signal-to-noise ratio) and subjective (video-quality metrics) indicators. 相似文献
8.
Approximate maximum likelihood (ML) hidden Markov modeling using the most likely state sequence (MLSS) is examined and compared with the exact ML approach that considers all possible state sequences. It is shown that for any hidden Markov model (HMM), the difference between the approximate and the exact normalized likelihood functions cannot exceed the logarithm of the number of states divided by the dimension of the output vectors (frame length), which is negligible for typically used values of vector dimension (128–256) and number of states (2–30). Furthermore, for Gaussian HMMs and a given observation sequence, the MLSS is typically the sequence of nearest neighbor states in the Itakura-Saito sense, and the posterior probability of any state sequence which departs from the MLSS in a single time instant decays exponentially with the frame length. Hence, for a sufficiently large frame length the exact and approximate ML approaches provide similar model estimates and likelihood values. The results and their implications on speech recognition are demonstrated in a set of experiments. 相似文献
9.
Neri Merhav Bhaskaran Vasudev 《Journal of Visual Communication and Image Representation》1996,7(4):395-410
In prior work, we developed a fast inverse motion compensation method that can be implemented directly on the DCT domain representation derived from the compressed bitstreams conforming to MPEG, H.261, and H.263 standards. That work was restricted to compressed-domain representations wherein the motion-vectors have integer pel accuracy. Here, we extend this work to fractional-pel accurate motion-vectors. We also extend the prior work to speed up the inverse motion compensation process in the DCT domain by explicitly exploiting the sparseness of the DCT domain representation. Using partial DCT information, we show that the DCT domain method has substantially lower operation count than the conventional spatial domain approach which requires decompression followed by inverse motion-compensation. 相似文献
10.
FilippoDiGiovanni GnetanoBazzano AntonioGrimaldi 《今日电子》2003,(3):40-41
功率转换器的功率密度越来越高,发热问题越来越严重,这种功率转换器的设计对现代大功率半导体技术提出了新的挑战;因而,热问题的优化设计和核实变得比大功率器件的电模型更加重要,本文提出一种新的PSPICE模型,可以利用它计算MOSFET芯片在瞬变过程中的温度。其中的热阻可以从制造商提供的产品使用说明书得到。本文介绍的模型提供发热和电气参数之间的动态关系。它建立了与许可的热环境的关系,例如,栅极驱动电路、负载、以及散热器的分析与优化设计。利用这个模型可以改善散热器的设计。由于决定功率损耗的参数是分布在一定范围内,受生产制造的影响很大,因而散热器的设计往往由于无法预先知道功率损耗而无法进行。 相似文献