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排序方式: 共有1260条查询结果,搜索用时 31 毫秒
1.
Lili Chen Nanami Fujisawa Masato Takanohashi Mazaya Najmina Koichiro Uto Mitsuhiro Ebara 《International journal of molecular sciences》2021,22(5)
This study demonstrates the rational fabrication of a magnetic composite nanofiber mesh that can achieve mutual synergy of hyperthermia, chemotherapy, and thermo-molecularly targeted therapy for highly potent therapeutic effects. The nanofiber is composed of biodegradable poly(ε-caprolactone) with doxorubicin, magnetic nanoparticles, and 17-allylamino-17-demethoxygeldanamycin. The nanofiber exhibits distinct hyperthermia, owing to the presence of magnetic nanoparticles upon exposure of the mesh to an alternating magnetic field, which causes heat-induced cell killing as well as enhanced chemotherapeutic efficiency of doxorubicin. The effectiveness of hyperthermia is further enhanced through the inhibition of heat shock protein activity after hyperthermia by releasing the inhibitor 17-allylamino-17-demethoxygeldanamycin. These findings represent a smart nanofiber system for potent cancer therapy and may provide a new approach for the development of localized medication delivery. 相似文献
2.
Masahiro Sato Miyu Koriyama Satoshi Watanabe Masato Ohtsuka Takayuki Sakurai Emi Inada Issei Saitoh Shingo Nakamura Kazuchika Miyoshi 《International journal of molecular sciences》2015,16(8):17838-17856
Some reports demonstrated successful genome editing in pigs by one-step zygote microinjection of mRNA of CRISPR/Cas9-related components. Given the relatively long gestation periods and the high cost of housing, the establishment of a single blastocyst-based assay for rapid optimization of the above system is required. As a proof-of-concept, we attempted to disrupt a gene (GGTA1) encoding the α-1,3-galactosyltransferase that synthesizes the α-Gal epitope using parthenogenetically activated porcine oocytes. The lack of α-Gal epitope expression can be monitored by staining with fluorescently labeled isolectin BS-I-B4 (IB4), which binds specifically to the α-Gal epitope. When oocytes were injected with guide RNA specific to GGTA1 together with enhanced green fluorescent protein (EGFP) and human Cas9 mRNAs, 65% (24/37) of the developing blastocysts exhibited green fluorescence, although almost all (96%, 23/24) showed a mosaic fluorescent pattern. Staining with IB4 revealed that the green fluorescent area often had a reduced binding activity to IB4. Of the 16 samples tested, six (five fluorescent and one non-fluorescent blastocysts) had indel mutations, suggesting a correlation between EGFP expression and mutation induction. Furthermore, it is suggested that zygote microinjection of mRNAs might lead to the production of piglets with cells harboring various mutation types. 相似文献
3.
Takauchi H. Tamura H. Matsubara S. Kibune M. Doi Y. Chiba T. Anbutsu H. Yamaguchi H. Mori T. Takatsu M. Gotoh K. Sakai T. Yamamura T. 《Solid-State Circuits, IEEE Journal of》2003,38(12):2094-2100
We describe a CMOS multichannel transceiver that transmits and receives 10 Gb/s per channel over balanced copper media. The transceiver consists of two identical 10-Gb/s modules. Each module operates off a single 1.2-V supply and has a single 5-GHz phase-locked loop to supply a reference clock to two transmitter (Tx) channels and two receiver (Rx) channels. To track the input-signal phase, the Rx channel has a clock recovery unit (CRU), which uses a phase-interpolator-based timing generator and digital loop filter. The CRU can adjust the recovered clock phase with a resolution of 1.56 ps. Two sets of two-channel transceiver units were fabricated in 0.11-/spl mu/m CMOS on a single test chip. The transceiver unit size was 1.6 mm /spl times/ 2.6 mm. The Rx sensitivity was 120-mVp-p differential with a 70-ps phase margin for a common-mode voltage ranging from 0.6 to 1.0 V. The evaluated jitter tolerance curve met the OC-192 specification. 相似文献
4.
Masato Enomoto 《Metallurgical and Materials Transactions A》1991,22(6):1235-1245
A previously developed computer model was modified to simulate the growth of grain boundary precipitates which grow by the ledge mechanism. The ledges were assumed to be nucleated in the grain boundary region at constant, parabolically decreasing, and random rates and to grow under the control of volume diffusion of solute to or from the riser of ledges. At lower under coolings at which the motion of individual ledges is slow, late-nucleated ledges soon catch up with first-nucleated ones, and precipitates tend to extend along the grain boundary: the overall precipitate shape is essentially that of a grain boundary allotriomorph. At larger undercoolings, first-nucleated ledges move fast to form a protuberance similar to Widmanstätten sideplates, while late-nucleated ones stay near the grain boundary region. The transition of precipitate shape from one to the other occurs in a very narrow range of supersaturation. The results are compared with various characteristics of the growth of proeutectoid ferrite allotriomorphs and sideplates in Fe-C alloys documented in the literature. 相似文献
5.
Keita Ikeue Shingo Ando Tomohiro Mitsuyama Yusuke Ohta Keishi Arayama Akiko Tsutsumi Masato Machida 《Topics in Catalysis》2008,47(3-4):175-180
Lanthanide-based oxysulfides and sulfide, LnTaO3.5S0.5, Ln10OS14 (Ln = La, Pr, Nd, Sm) and La4In5S13, were successively synthesized by sulfurization in a flowing H2S. The sulfurization decreased the band-gap energies from >4 eV to <3eV, because of the formation of occupied S3p orbitals
on the top of valence band. In accordance with the small band gap, the H2 evolution from a 0.01 M Na2S and 0.01 M Na2SO3 solution system was observed under irradiation of light up to >500 nm. The rate of H2 evolution under light irradiation of >500 nm increased in the order of Ni/LaTaO3.5S0.5 < Ru/La10OS14 < Pt/La4In5S13. 相似文献
6.
Masato Tanaka 《加拿大化工杂志》1985,63(5):723-727
The local variation of droplet diameter in a stirred tank was measured in the vicinity of the impeller and at another region. The degree of difference in droplet diameter between regions increases with the impeller speed. A correlation equation between the local difference in droplet diameter and the frequencies of coalescence and circulation of the droplet was derived according to the circulation interaction model. The degree of local difference in droplet diameter was found to be controlled strongly by the ratio of coalescence to circulation frequency. 相似文献
7.
Chemotaxis of guinea pig eosinophils induced by various stimuli in use of a modified Boyden chamber technique in vitro and the effect of a platelet-activating factor (PAF) antagonist, apafant (CAS 105219-56-5, WEB 2086 BS), on it were examined. The eosinophils were obtained by bronchoalveolar lavage from the animals treated by i.v. injection with Sephadex G-200 and purified by Percoll density gradient centrifugation. PAF significantly and potently induced the chemotaxis at a broad range of 10(-17) to 10(-7) mol/l, where no concentration-dependency was observed. Leukotriene B4 also induced the chemotaxis in a concentration-dependent manner at 10(-14) to 10(-12) mol/l and the enhanced migration was not declined until 10(-7) mol/l. Interleukin-5 (IL-5), IL-8 and regulated on activation normal T expressed and secreted (RANTES) only modestly enhanced the chemotaxis in some concentrations at 10(-13) to 10(-7) mol/l with or without significance and with no concentration-dependency while formyl-methionyl-leucyl-phenylalanine (FMLP), a known chemoattractant, increased the migration at 10(-7) to 10(-5) mol/l. Apafant at 10(-8) to 10(-6) mol/l strongly and concentration-dependently inhibited 10(-8) mol/l PAF-induced chemotaxis. However, the drug showed nominal or no influences on their chemotaxis stimulated by the other agonists, at the concentrations of which the enhanced migration was observed. From these results, it is concluded that IL-5, IL-8 and RANTES, different from PAF and LTB4, are not potent stimuli for the eosinophil chemotaxis and that apafant is a selective antagonist of PAF, which is expected to be therapeutically effective for PAF-associated diseases including bronchial asthma. 相似文献
8.
Miao Wang Xinluo Zhao Masato Ohkohchi Yoshinori Ando 《Fullerenes, Nanotubes and Carbon Nanostructures》1996,4(5):1027-1039
Carbon nanotubes prepared by de arc discharge of graphite electrodes in He and CH4 gas took markedly different morphology. Thick nanotubes embellished with many carbon nanoparticles were obtained by evaporation under high CH4 gas pressure and high arc current. Thin and long carbon nanotubes were obtained under a CH4 gas pressure of 50Torr and an arc current of 20A for the anode with a diameter of 6mm. 相似文献
9.
Masato Miyauchi Atsuko Miyake Yukio Nakanishi Yasuyuki Sagara 《Drying Technology》1995,13(8):1741-1761
An experimental study has been carried out on the characteristics of binary adsorption isotherms of water and volatile flavor for typical materials used in a box of a tobacco product or cigarettes. Ethyl acetate chosen as a model for water-soluble volatile flavor. Binary adsorption isotherms for the tobacco, papers, filters, and activated carbons were measured with a flow-type multi-component adsorption system under the canstant conditions of temperature a t 303 K and vapor pressure of water a t 2.5 kPain the vapor pressure range of ethyl acetate from 0 to 4.2 kPa. A linear equation was applied to express the binary adsorption isotherms for the tobacco, papers and filters, while a Dubinin-Astakhov equation was applied for the activated carbons. The binary adsorption was characterized into three groups, depending on the selectivity as well as the mechanism of adsorption; i.e.(l) for tobacco and papers, water was adsorbed much greater rather than ethyl acetate, (2) for filters, ethyl acetate was adsorbed on the surface as great as water, (3) for activated carbons, ethyl acetate was adsorbed much greater onto their micropores rather than water. The results showed that ethyl 相似文献
10.
The catalytic activity of KGa-priderite, K1.6Ga1.6Ti6.4O16, and its related compound KGa8Ga9Ti15O56 was investigated for the selective reduction of nitrogen monoxide (NO) with propylene (C3H6) in the presence of high oxygen concentrations. The KGa-priderite showed significant activity during this reaction, but the related compound showed only a little activity. These compounds are quite different from the conventional catalysts for NOx selective reduction and are characterized by the fact that their properties are free from the effects of solid acidity and support metals. This difference was attributable to the NO desorption rate at the surface of these compounds. It has become clear that the KGa-priderite catalyst remarkably adsorbed NO, and it is suggested that the amount of NO adsorbed and the amount of catalytic activity are able to be increased by the design of priderite structure. 相似文献