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排序方式: 共有526条查询结果,搜索用时 15 毫秒
31.
Roberta Squecco Alessia Tani Flaminia Chellini Rachele Garella Eglantina Idrizaj Irene Rosa Sandra Zecchi-Orlandini Mirko Manetti Chiara Sassoli 《International journal of molecular sciences》2021,22(7)
Bone marrow-mesenchymal stem/stromal cells (MSCs) may offer promise for skeletal muscle repair/regeneration. Growing evidence suggests that the mechanisms underpinning the beneficial effects of such cells in muscle tissue reside in their ability to secrete bioactive molecules (secretome) with multiple actions. Hence, we examined the effects of MSC secretome as conditioned medium (MSC-CM) on ex vivo murine extensor digitorum longus muscle injured by forced eccentric contraction (EC). By combining morphological (light and confocal laser scanning microscopies) and electrophysiological analyses we demonstrated the capability of MSC-CM to attenuate EC-induced tissue structural damages and sarcolemnic functional properties’ modifications. MSC-CM was effective in protecting myofibers from apoptosis, as suggested by a reduced expression of pro-apoptotic markers, cytochrome c and activated caspase-3, along with an increase in the expression of pro-survival AKT factor. Notably, MSC-CM also reduced the EC-induced tissue redistribution and extension of telocytes/CD34+ stromal cells, distinctive cells proposed to play a “nursing” role for the muscle resident myogenic satellite cells (SCs), regarded as the main players of regeneration. Moreover, it affected SC functionality likely contributing to replenishment of the SC reservoir. This study provides the necessary groundwork for further investigation of the effects of MSC secretome in the setting of skeletal muscle injury and regenerative medicine. 相似文献
32.
An improved method is described for the sol–gel preparation of PLZT thin layers in the perovskite structure. The method uses a PbO cover coat. Details are reported for the sol-gel processing route and heat-treatment conditions. Through use of this method it is possible to prepare singlephase perovskite material with improved properties. The deleterious effect of additional phases—which are not present when a PbO cover coat is used—is attributed to Pb loss from the surface during thermal processing. Examples are given for PLZT thin layers integrated on Si with and without a PbO cover coat. The dielectric and ferroelectric properties were always found to be superior for coated structures. 相似文献
33.
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
34.
Shown in this paper is a practical method of control using neural network and fuzzy control techniques, where a neural network estimates the target of fuzzy control. The neural network is used to estimate the transient state of a plant which has nonlinear processes such as refrigerating and filtering. The suitable control target pattern for fuzzy control is selected according to this estimation. This method is applied to control the tank level of a solvent dewaxing plant for: 1) changing the tank outflow rate smoothly, and 2) keeping the tank level stable. The results show that this system can control the tank level effectively in both steady state and transient state 相似文献
35.
Optically active alcohol is an important building block as a versatile chiral synthon for the asymmetric synthesis of pharmaceuticals and agrochemicals. We purified and characterized glycerol dehydrogenase from Hansenula ofunaensis and prepared optically active 1,2-octanediol using a recombinant Escherichia coli harboring the glycerol dehydrogenase gene. The deduced amino acid sequence was investigated for identities with those of other alcohol dehydrogenases in the NCBI databank. The identification of the unknown product of a resting-cell reaction was performed by GC-MS. In the deduced amino acid sequence composed of 376 residues, the NAD(H) binding pattern and cysteine residues that correspond to the cysteine ligands at the zinc atom were conserved as they are in alcohol dehydrogenases from other origins. Glycerol dehydrogenase from Hansenula polymorpha DL-1 (Pichia angusta, DDBJ/EMBL/GenBank accession no. BAD32688) had the highest identity to our enzyme, showing 73% identity. Our glycerol dehydrogenase catalyzed the NAD(+)-dependent oxidation of long-chain secondary alcohols such as 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, and 1,2-octanediol. Activities toward 2,4-pentanediol and 2,5-hexanediol were hardly detected. From these results, it was confirmed that our enzyme requires two hydroxyl groups on adjacent carbon atoms for oxidation. 2,3-Pentanedione, 2,3-hexanedione, and 3,4-hexanedione were significantly reduced. The transformants oxidized only (R)-1,2-octanediol in 50 mM racemate (R:S=52:48), and produced (S)-1,2-octanediol (24 mM, <99.9% e.e.) after 24 h of incubation. The reaction product was suggested to be 1-hydroxy-2-octanone by GC-MS, which showed secondary hydroxyl groups oxidized. Glycerol dehydrogenase from H. ofunaensis could be useful for the production of long-chain optically active secondary alcohols. 相似文献
36.
功能纤维的现状和展望 总被引:3,自引:0,他引:3
综述了日本已开发的功能纤维的品种 ,技术措施 ;日本、美国在新世纪研究开发新纤维的规划、设想 ,中长期开发课题、技术战略 ,指出了 2 1世纪功能纤维的开发应用前景。 相似文献
37.
Masashi Totokawa Syuichi Yamashita Kenji Morikawa Yoshihito Mitsuoka Toshihiko Tani Hiroaki Makino 《International Journal of Applied Ceramic Technology》2009,6(2):195-204
The piezoresistive mechanisms of composite thick films based on RuO2 particles and both calcium-borosilicate and bismuth-borosilicate glass matrices were investigated by chemical and electrical microanalyses. The resistor based on bismuth-borosilicate glass showed higher sensitivity than that based on calcium-borosilicate glass. It was confirmed that the diffusion of ruthenium into glass affects the binding state of RuO2 at the interface of the glass. Furthermore, an intermediate resistive layer is detected around the RuO2 particle. These results suggest that the piezoresistive effect is related to a change in the electrical conductivity of the interfacial reaction layer caused by the diffusion of ruthenium into glass. 相似文献
38.
A photoconductive dipole antenna can be used as a transceiver, which alternately transmits pulsed electromagnetic radiation and receives the return signal. Preliminary results of using a photoconductive terahertz transceiver with femtosecond optics are reported 相似文献
39.
H. Mimata K. Tani K. Tobita H. Tsutsui S. Tsuji-Iio R. Shimada 《Progress in Nuclear Energy》2008,50(2-6):638
The confinement of alpha particle is important in tokamaks. The trajectory or confinement of alpha particles is often calculated with guiding center approximation. The features of spherical tokamak can break the approximation. We investigate finite Larmor radius effect. The orbit calculated by equation of motion is different, especially in toroidal direction, from that by guiding center equations. This difference causes difference of ripple resonance energy and the difference of the peaks of the diffusion coefficients. Furthermore, because of the additional free parameter, Larmor phase, the peaks of diffusion coefficient calculated by equation of motion are broader than those by guiding center equations. 相似文献
40.
Yoshida N Akazawa S Karino T Ishida H Hata Y Katsuragi T Tani Y Takagi H 《Journal of Bioscience and Bioengineering》2007,104(5):424-427
We found 11 genes (FAO1-11) encoding putative oxidoreductases in the Aspergillus oryzae genome, which are similar to fungal fructosyl-amino acid oxidases. The cDNAs corresponding to the genes were cloned and expressed in Escherichia coli. rFao2 had fructosyl-amino acid oxidase activity, whereas rFao1 did not show any enzyme activity, even though the deduced amino acid sequence of Fao1 is identical to that of one of the fructosyl-amino acid oxidase isozymes from Aspergillus oryzae. rFao7 and rFao8 showed oxidase activity toward sarcosine, L-pipecolate, and L-proline. rFao10 was active toward only sarcosine, of the substrates tested. The functions of the other proteins were also predicted from a phylogenetic analysis. 相似文献