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排序方式: 共有694条查询结果,搜索用时 15 毫秒
101.
Rodella LF Favero G Boninsegna R Buffoli B Labanca M Scarì G Sacco L Batani T Rezzani R 《Microscopy research and technique》2011,74(8):772-777
An interesting clinical option for optimizing healing tissue is the use of platelet concentrate. Platelets contain high quantities of growth factors, among these TGF-β1 and VEGF, which are known to be implicated in tissue regeneration. CGF is produced by processing blood samples with a special centrifuge device; three layers are formed: top acellular plasma (PPP), middle CGF and bottom red blood cells (RBC) layers. Given that to date there are no data concerning the biological characteristic of CGF, the aim of this study was to evaluate the presence of TGF-β1 and VEGF in CGF and also in PPP and RBC layers. In addition, since circulating stem cells are recruited from blood to injured tissue for healing we also evaluated the presence of CD34 positive cells. Our data show the presence of TGF-β1 and VEGF in CGF and RBC layers. In addition, we show CD34 positive cells in CGF. 相似文献
102.
Ramon delos Santos Valynn Mag-usara Anthony Tuico Vernalyn Copa Arnel Salvador Kohji Yamamoto Armando Somintac Kazuyoshi Kurihara Hideaki Kitahara Masahiko Tani Elmer Estacio 《Journal of Infrared, Millimeter and Terahertz Waves》2018,39(6):514-520
The influence of crystal thickness of metal-coated <100>-cut GaAs (M-G-M) on Cherenkov-phase-matched terahertz (THz) pulse detection was studied. The M-G-M detectors were utilized in conjunction with a metallic tapered parallel-plate waveguide (TPPWG). Polarization-sensitive measurements were carried out to exemplify the efficacy of GaAs in detecting transverse magnetic (TM)- and transverse electric (TE)-polarized THz waves. The reduction of GaAs’ thickness increased the THz amplitude spectra of the detected TM-polarized THz electro-optic (EO) signal due to enhanced electric field associated with a more tightly-focused and well-concentrated THz radiation on the thinner M-G-M. The higher-fluence THz beam coupled to the thinner M-G-M improved the integrated intensity of the detected THz amplitude spectrum. This trend was not observed for TE-polarized THz waves, wherein the integrated intensities were almost comparable. Nevertheless, good agreement of spectral line shapes of the superposed TM- and TE-polarized THz-EO signals with that of elliptically polarized THz-EO signal demonstrates excellent polarization-resolved detection capabilities of M-G-M via Cherenkov-phase-matched EO sampling technique. 相似文献
103.
Hannes Ramon Haolin Li Piet Demeester Johan Bauwelinck Guy Torfs 《Journal of Signal Processing Systems》2018,90(3):295-303
This article describes a method for increasing the sampling rate of efficient polyphase arbitrary resampling FIR filters. An FPGA proof of concept prototype of this architecture has been implemented in a Xilinx Kintex-7 FPGA which is able to convert the sampling rate of a signal from 500 MHz to 600 MHz. This article compares this new architecture with other best known efficient resampling architectures implemented on the same FPGA. The area usage on the FPGA shows that our proposed implementation is very proficient in high bandwidth applications without requiring significantly more resources on the FPGA. A theoretical calculation of the resampling error introduced on a modulated data stream is provided to evaluate the new architecture against other existing resampling architectures. 相似文献
104.
Hector Lopez-Laguna Rafael Cubarsi Ugutz Unzueta Ramon Mangues Esther Vazquez Antonio Villaverde 《SCIENCE CHINA Materials》2020,(4):644-653
Poly-histidine peptides such as H6(HHHHHH)are used in protein biotechnologies as purification tags,protein-assembling agents and endosomal-escape entities.The pleiotropic properties of such peptides make them appealing to design protein-based smart materials or nanoparticles for imaging or drug delivery to be produced in form of recombinant proteins.However,the clinical applicability of H6-tagged proteins is restricted by the potential immunogenicity of these segments.In this study,we have explored several humanized histidine-rich peptides in tumor-targeted modular proteins,which can specifically bind and be internalized by the target cells through the tumoral marker CXCR4.We were particularly interested in exploring how protein purification,self-assembling and endosomal escape perform in proteins containing the variant histidine-rich tags.Among the tested candidates,the peptide H5 E(HEHEHEHEH)is promising as a good promoter of endosomal escape of the associated fulllength protein upon endosomal internalization.The numerical modelling of cell penetration and endosomal escape of the tested proteins has revealed a negative relationship between the amount of protein internalized into target cells and the efficiency of cytoplasmic release.This fact demonstrates that the His-mediated,proton sponge-based endosomal escape saturates at moderate amounts of internalized protein,a fact that might be critical for the design of protein materials for cytosolic molecular delivery. 相似文献
105.
106.
Cintia Ocampo Ramon Oliver Elaine Armelin Carlos Alemán Francesc Estrany 《Journal of Polymer Research》2006,13(3):193-200
Electrodeposition of poly(3,4-ethylenedioxythiophene) by electrochemical polymerization of 3,4-ethylenedioxythiophene has
been performed on steel electrodes rather than on the typically used inert electrodes (Pt, Au, graphite carbon). The polymer
was generated by cyclic voltammetry, chronopotentiometry and chronoamperometry from a 10 mM monomer solution in acetonitrile
with 0.1 M LiClO4. Elemental analysis of the generated polymer indicated that the monomeric units support 0.54 positive charges balanced with
CIO4
14− counterions. Electrochemical, electrical and structural properties of the prepared material have been characterized. The
good adherence of films combined with its excellent properties indicate that poly(3,4-ethylenedioxythiophene) can be a suitable
material for anticorrosion applications. 相似文献
107.
Dr. Ignacio Delso Dr. Jessika Valero‐Gonzalez Dr. Fernando Gomollón‐Bel Jorge Castro‐López Dr. Wenxia Fang Dr. Iva Navratilova Prof. Daan M. F. van Aalten Prof. Tomás Tejero Prof. Pedro Merino Dr. Ramon Hurtado‐Guerrero 《ChemMedChem》2018,13(2):128-132
Fungal β‐1,3‐glucan glucanosyltransferases are glucan‐remodeling enzymes that play important roles in cell wall integrity, and are essential for the viability of pathogenic fungi and yeasts. As such, they are considered possible drug targets, although inhibitors of this class of enzymes have not yet been reported. Herein we report a multidisciplinary approach based on a structure‐guided design using a highly conserved transglycosylase from Sacharomyces cerevisiae, that leads to carbohydrate derivatives with high affinity for Aspergillus fumigatus Gel4. We demonstrate by X‐ray crystallography that the compounds bind in the active site of Gas2/Gel4 and interact with the catalytic machinery. The topological analysis of noncovalent interactions demonstrates that the combination of a triazole with positively charged aromatic moieties are important for optimal interactions with Gas2/Gel4 through unusual pyridinium cation–π and face‐to‐face π–π interactions. The lead compound is capable of inhibiting AfGel4 with an IC50 value of 42 μm . 相似文献
108.
Alicia De San Luis Ziortza Aguirreurreta Leticia M. Pardo Ana Perez-Marquez Jon Maudes Nieves Murillo María Paulis Jose Ramon Leiza 《Israel journal of chemistry》2018,58(12):1347-1355
Hybrid nanofibers containing CdSe/ZnS quantum dots have been produced by electrospinning of hybrid latexes to characterize the electro-optical behavior of this novel luminescent sensing material. The latexes are synthesized by seeded semi-batch emulsion polymerization yielding cross-linked core-shell PS/QDs/PMMA particles with efficiently encapsulated quantum dots guaranteeing a good optical stability. Addition of polyvinyl alcohol (PVA) or polyethylene oxide (PEO) to the latexes is necessary to produce polymeric dispersions suitable for electrospinning manufacture of the nanometric fibers. The optimized polymeric dispersions are successfully electrospun obtaining fluorescent nanofibers in both cases. The hybrid nanofibers are sensitive to selected solvents (acetone, methanol and THF) and present positive response making them good candidates for the production of VOC sensors. 相似文献
109.
A tree‐based algorithm for virtual infrastructure allocation with joint virtual machine and network requirements
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Ramon de Oliveira Guilherme Piegas Koslovski 《International Journal of Network Management》2017,27(1)
Cloud providers have introduced the on‐demand provisioning of virtual infrastructures (VIs) to deliver virtual networks of computing resources as a service. By combining network and computing virtualization, providers allow traffic isolation between hosted VIs. Taking advantage of this opportunity, tenants have deployed private VIs with application‐optimized network topologies to increase quality of experience of final users. One of the main open challenges in this scenario is the allocation of physical resources to host VIs in accordance with quality of service computing (eg, virtual CPUs and memory) and network requirements (guaranteed bandwidth and specific network topology). Moreover, a VI can be allocated anywhere atop a network datacenter, and because of its NP‐hard complexity, the search for optimal solutions has a limited applicability in cloud providers as requesting users seek an immediate response. The present work proposes an algorithm to accomplish the VI allocation by applying tree‐based heuristics to reduce the search space, performing a joint allocation of computing and network resources. So as to accomplish this goal, the mechanism includes a strategy to convert physical and virtual graphs to trees, which later are pruned by a grouped accounting algorithm. These innovations reduce the number of comparisons required to allocate a VI. Experimental results indicate that the proposed algorithm finds an allocation on feasible time for different cloud scenarios and VI topologies, while maintaining a high acceptance rate and a moderate physical infrastructure fragmentation. 相似文献
110.
Cover Picture: Stabilization of Telomeric I‐Motif Structures by (2′S)‐2′‐Deoxy‐2′‐C‐Methylcytidine Residues (ChemBioChem 12/2017)
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