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31.
Phellinus baumii, a fungus that grows on mulberry trees and is used in traditional Chinese medicine, exerts therapeutic effects against various diseases, including cancer. Polyphenols, generally considered to be antioxidants, have antitumor and proapoptotic effects. In this study, we identified the composition of Phellinus baumii polyphenol (PBP) and characterized its 17 chemical components by UPLC–ESI–QTOF–MS. Furthermore, to clarify the potential mechanism of PBP against Lung Cancer Cells, network pharmacology and experimental verification were combined. Molecular docking elucidated the binding conformation and mechanism of the primary active components (Osmundacetone and hispidin) to the core targets CASP3, PARP1 and TP53. In addition, potential molecular mechanisms of PBP predicted by network pharmacology analysis were validated in vitro. PBP significantly inhibited the human lung cancer A549 cells and showed typical apoptotic characteristics, without significant cytotoxicity to normal human embryonic kidney (HEK293) cells. Analysis using flow cytometry and western blot indicated that PBP caused apoptosis, cell cycle arrest, reactive oxygen species (ROS) accumulation, and mitochondrial membrane potential (MMP) depression in A549 cells to exercise its antitumor effects. These results reveal that PBP has great potential for use as an active ingredient for antitumor therapy.  相似文献   
32.
LED环氧树脂封装材料研究进展   总被引:4,自引:0,他引:4  
针对封装材料在使用中的缺陷,综述了对环氧树脂的增韧、提高耐热性、改善透明性、改善加工性能的研究现状,并介绍了LED环氧树脂封装材料的发展前景。  相似文献   
33.
In this work, we investigate the influence of defect concentration of the diamond substrates on the performance of hydrogen-terminated diamond field-effect transistors by Raman spectra, pulsed IV characteristics analysis, and radio frequency performances measurements. It is found that a sample with higher defect concentration shows larger drain-lag effect and lower large-signal output power density. Defects in the diamond act as traps in the carrier transport and have a considerable influence on the large-signal output power density of diamond field-effect transistors. This work should be helpful for further performance improvement of the microwave power diamond devices.  相似文献   
34.
We investigate the hot carrier injection effect (HCI) and how X-ray radiation impacts the HCI of 22-nm nFinFETs as a function of device geometry and irradiation bias conditions in this paper. In the HCI test, the degradation of threshold voltage and saturation current decreases with the increase of fin number, which means that HCI weakens when the fin number increases. The reason is attributed to the coupling effect between fins. Moreover, irradiation is shown to weaken the degradation during the subsequent hot carrier test. The influence of irradiation on HCI is more obvious with ON bias than that of OFF bias and transmission gate bias. It is supposed that the Si–H bonds can be broken by irradiation before the HCI test, which is one reason for the irradiation influence on HCI. Besides, trapped charges are generated in the shallow trench isolation by the radiation, which could reduce the channel electric field, and then weaken the HCI.  相似文献   
35.
本文设计了一种六足气动机器人,由本体、六条相同的腿部、足部等连接件组成。六条腿部对称呈对称分布与本体两侧。腿部具有柔性关节。通过控制向腿部气橡囊中通入气体的压力及方向的不同,可实现机器人腿部轴向伸缩和弯曲变形。并通过步态规划实现了机器人的前后移动,为气动柔性机器人的研究提供一定的理论基础。  相似文献   
36.
结合实践经验,提出了仪器仪表设备故障诊断的基本思路,并归纳出易引起故障的原因及故障诊断的方法.  相似文献   
37.
催化加氢法合成苯甲醛研究进展   总被引:1,自引:0,他引:1  
综述了国内外苯甲酸及其酯催化加氢制备苯甲醛技术的研究进展,并针对当前研究状况,提出了改进办法以及新型苯甲醛生产综合途径。  相似文献   
38.
Cinnamoyl-CoA reductase (CCR) is a pivotal enzyme in plant lignin synthesis, which has a role in plant secondary cell wall development and environmental stress defense. Alfalfa is a predominant legume forage with excellent quality, but the lignin content negatively affects fodder digestibility. Currently, there is limited information on CCR characteristics, gene expression, and its role in lignin metabolism in alfalfa. In this study, we identified 30 members in the CCR gene family of Medicago sativa. In addition, gene structure, conserved motif, and evolution analysis suggested MsCCR1–7 presumably functioned as CCR, while the 23 MsCCR-likes fell into three categories. The expression patterns of MsCCRs/MsCCR-likes suggested their role in plant development, response to environmental stresses, and phytohormone treatment. These results were consistent with the cis-elements in their promoters. Histochemical staining showed that lignin accumulation gradually deepened with the development, which was consistent with gene expression results. Furthermore, recombinant MsCCR1 and MsCCR-like1 were purified and the kinetic parameters were tested under four substrates. In addition, three-dimensional structure models of MsCCR1 and MsCCR-like1 proteins showed the difference in the substrate-binding motif H212(X)2K215R263. These results will be useful for further application for legume forage quality modification and biofuels industry engineering in the future.  相似文献   
39.
描述了工程图档管理系统在企业中的应用和在企业管理系统中的作用,分析了它的功能特点和组成,并简述了用VisualBasic设计开发一个工程图档管理系统的过程。  相似文献   
40.
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