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排序方式: 共有508条查询结果,搜索用时 140 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
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Zhang Kai Song Feilong Jin Di Xu Shida Sun Jiulun Huang Shengfang 《International Journal of Hydrogen Energy》2021,46(13):9019-9029
To improve the quality of pre-combustion cracking gas, the gliding arc discharge plasma is adopted in this paper. The influence of incoming flow rate, electrode gap distance and discharge frequency on cracking effect have been experimentally studied. The results show that through plasma cracking, the concentration of H2 increases while the concentration of CH4 and C2H4 decrease. With different fuel ratio conditions, the variation trend of C/H ratio as well as the mass flow of carbon and hydrogen atoms in the cracking products vary from each other. The cracking effect becomes weaker with the increase of incoming flow rate, while is better when the fuel ratio is larger. Given the flow rate of 18slpm and 24slpm, the best cracking effect can be acquired with the electrode gap of 1.5 mm. Besides, the effect of gliding arc discharge plasma cracking is weakened as the discharge frequency rises. 相似文献
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Naoya Kanbayashi Arisa Yamazawa Koichiro Takii Taka‐aki Okamura Kiyotaka Onitsuka 《Advanced Synthesis \u0026amp; Catalysis》2016,358(4):555-560
We report the asymmetric allylic alkylation of allylic chlorides with silyl enolates as a carbon nucleophile using a planar‐chiral cyclopentadienyl‐ruthenium (Cp′Ru) catalyst. The reaction proceeds under unusually mild conditions to give the desired branched products with complete regioselectivity and high enantioselectivity, and reactive functional groups, such as aldehyde, can be tolerated. In this reaction system, Cp′Ru plays an important role in activating both silyl enolate and allylic chloride.
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我国西北地区日、年温差大,混凝土经历着温差产生的热疲劳劣化。保持环境湿度恒定,在20 ℃、30 ℃、40 ℃温差下开展两种强度等级的混凝土热疲劳试验,测定其抗压强度、劈裂抗拉强度等宏观性能变化规律;通过超声无损检测技术和压汞试验测定微观结构。结果表明:热疲劳劣化效应明显,随循环温差的增大和循环次数增加,混凝土强度下降明显,C40混凝土下降幅度大于C25混凝土,且劈裂抗拉强度较抗压强度对热疲劳作用更敏感;超声波速呈减小趋势,说明混凝土内部裂隙缺陷增多;同一循环温差下,混凝土的孔隙率、孔隙总体积、平均孔径、中值孔径、最可几孔径随温差循环次数增加而增大,孔隙总表面积减小,孔隙结构表现出粗化的特征且呈劣化的趋势,C40混凝土的孔隙率小于C25混凝土,但其孔隙率相对变化值更大,从微观层面揭示了混凝土在热疲劳作用下强度损伤的内在原因。 相似文献
6.
Toru Moriyama Jun-ichi Mashiko Toshinori Matsui Koichiro Enomoto Tetsuya Matsui Kojiro Iizuka Masashi Toda Yukio Pegio Gunji 《Artificial Life and Robotics》2016,21(3):247-252
The soldier crab appears in great numbers and feeds while wandering during daytime low tide. When they see an approaching object, they screw themselves into the sand. The mechanism of formation of mass wandering has not been clarified. In this study, to investigate if the soldier crabs use visual images of neighbors as a stimulus for wandering, dummy crabs were presented to crabs. In the experiments, one, two, four, or eight dummies were placed in a circle on a sand arena. Each crab was placed in the center of the arena and observed whether it burrowed into the sand or wandered. The proportions of wandering individuals in each experimental treatment were compared with the expected value. Significantly more crabs were wanderers when only two and four dummies were present. This result suggests that soldier crabs chose burrowing or wandering depending on visual image of the distribution of the neighbors. 相似文献
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An exact mass measurement ESI TOF mass spectrometer has been developed for fast pathogen identification and strain typing. This unique technology relies on mass spectrometry-derived base composition signatures of amplicons from PCR (Polymerase Chain Reaction) products, and “intelligent PCR primers” that target broadly conserved regions of microbial genomes that flank variable regions. This rapid detection (30 seconds per sample) and identification of microorganism methodology also associates with a potential biological warfare attack or a natural outbreak of an emerging infectious disease. The strategy to build a high end and low cost ESI TOF machine will be discussed. The performance data particularly in accurate mass measurement, high resolving power and 24 hours stability test will be presented. The discovery of Swine flu virus H1N1 will be presented as an example to illustrate the procedure of detection and identification of microoganisms. 相似文献