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排序方式: 共有2301条查询结果,搜索用时 15 毫秒
91.
Yingjie Shen Hyoung Jae Lee Rui Zhou Hangun Kim Gen Chen Young-Chang Cho Kwonseop Kim 《International journal of molecular sciences》2021,22(10)
Prostate cancer (PCa) is the second most leading cause of death in males. Our previous studies have demonstrated that δ-catenin plays an important role in prostate cancer progression. However, the molecular mechanism underlying the regulation of δ-catenin has not been fully explored yet. In the present study, we found that δ-catenin could induce phosphorylation of p21Waf and stabilize p21 in the cytoplasm, thus blocking its nuclear accumulation for the first time. We also found that δ-catenin could regulate the interaction between AKT and p21, leading to phosphorylation of p21 at Thr-145 residue. Finally, EGF was found to be a key factor upstream of AKT/δ-catenin/p21 for promoting proliferation and metastasis in prostate cancer. Our findings provide new insights into molecular controls of EGF and the development of potential therapeutics targeting δ-catenin to control prostate cancer progression. 相似文献
92.
Kiyoshi Dowaki Tsuyoshi Ohta Yasukazu Kasahara Mitsuo Kameyama Koji Sakawaki Shunsuke Mori 《Renewable Energy》2007,32(1):80-94
Recently, in Japan, recycling technologies have been developed using waste biomass material. Waste biomass is traded in the waste materials market between users and a third-party, who receives a fee for processing them. This study is an environmental and economic analysis of a biomass energy system, which can produce hydrogen fuel for fuel cells (purity of 99.99%) as an example of an environmental business model. The experimental apparatus was made based on the moving-bed gasifier by the German company, DM2 Inc., and the hydrogen gas yield was measured. Finally, the economic viability of the future hydrogen business was estimated.The experimental results obtained gave the gas concentration of 57.5% in a Steam/Carbon ratio of 1.40 at 900 °C.Assuming the plant scale of 10 t/d, the production amount of hydrogen gas would be 21.3 kg/h. Based on the law concerning waste processing in Japan, a sizeable amount of waste biomass could be expected. Therefore, if the processing fee which is paid to the group (contractor) ranges between 5.0 and 10.0 $/t, and if the whole investment cost is 6 million dollars and the depreciation period is 15 years, the bio-hydrogen production cost using the experimental data would be 5.75–7.86 $/kg-H2 without receiving related subsidies. In a one-third grant proportion, the cost would become 4.60–6.72 $/kg-H2. 相似文献
93.
94.
The efficiencies of recently proposed, phenyl addition/cyclization (PAC), methyl addition/cyclization (MAC) and a popular hydrogen abstraction/acetylene addition (HACA) mechanisms have been examined experimentally by detecting the gas phase reaction products of pyrolysis of toluene with/without addition of benzene + acetylene by using vacuum ultraviolet (VUV) single photon ionization (SPI) time of flight mass spectrometry (TOFMS). Besides the observation of verities of large polycyclic aromatic hydrocarbons (PAHs), intense mass peaks of indene, phenylacetylene and propyne confirmed a remarkable quenching of the major active species, benzyl, phenyl and methyl radicals by acetylene. In spite of quenching, only benzyl contributed products were diminished while phenyl and methyl contributed products were enhanced. Uniquely observed symmetrical PAHs; corrannulene/coronene; formed by the active involvement of PAC, HACA and/or MAC mechanisms, reflects the interdependencies of these mechanisms. Individually, PAC was found highly efficient for endless growth, HACA for filling triple fusing site and MAC for expanding cyclotetra/pentafused into benzenoid structure, respectively. 相似文献
95.
This study presents numerical analyses of transient temperature and thermally induced stress distributions in a stationary hollow steel disk partially heated by a moving uniform heat source from its outer surface under stagnant ambient conditions. The moving heat source applied on a certain angular segment of the processed surface rotates with a constant angular speed (ω). The peak levels of the temperature gradients and the thermal stress ratios at the heated segments do not rise very much after 2–3 cycles. When the value of ω is increased, the maximum effective thermal stress ratio can be decreased in a considerable amount. 相似文献
96.
非政府组织参与减灾的理性考量 总被引:1,自引:0,他引:1
在全球治理的背景下,非政府组织发挥自身的独特优势在构建非工程防灾减灾体系中大有可为。同时,减灾的本意昭示非政府组织可以在减少灾害,减轻灾害损失,摒除不利于减灾的思想和行为等方面发挥作用。在这一前提下,考察我国非政府组织参与减灾的阈失面,启示我们要加强防灾减灾的社会科学研究,强化非政府组织自身建设并建立公共服务社会化机制,为非政府组织参与减灾创设条件。从而,非政府组织参与减灾是防灾减灾非工程措施中的重要部分,对其所做的思考是探索非政府组织能否成为未来中国社会防灾减灾主导力量的重要依据。 相似文献
97.
98.
轴测图中半径、直径类尺寸在AutoCAD中的自动标注 总被引:1,自引:0,他引:1
在轴测图中圆的投影常为椭圆,为了在AutoCAD中标注这类投影为椭圆的圆或圆弧的半径、直径,进行了相应的程序开发。 相似文献
99.
100.
采用湿化学法制备了磷锑共掺氧化锡Sn1-3xSbxP2xO2+6(x=0.004,0.010,0.030,0.050)材料.利用XRD、SEM、电阻-温度特性测试系统和交流阻抗技术对所制氧化锡材料的物相组成、微观结构及导电特性进行了研究.结果表明:在x=0.004和0.010时,所制氧化锡材料由纯四方结晶相组成,但在x≥0.030时,材料中出现了微量的P2O5和SnP2O7杂质相;所制氧化锡材料的电阻-温度特性具有负温度系数(NTC)效应,选主要是晶粒效应和晶界效应共同作用的结果;最后利用能带理论对该材料的NTC导电机理进行了分析讨论. 相似文献