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排序方式: 共有358条查询结果,搜索用时 15 毫秒
81.
Long Cui Mun Ock Kim Jee Hee Seo Il Soon Kim Nam Ye Kim Sun Hwa Lee Jeongjun Park Jungwoo Kim Hyun Sun Lee 《Food chemistry》2012
Inhibition of acyl CoA:diacylglycerol acyltransferase (DGAT) has been proposed as one of the drug targets for treating obesity and type 2 diabetes. Bioassay-guided fractionation of the MeOH-soluble extract of Rosmarinus officinalis yielded two new diacylglycerol acyltransferase (DGAT) inhibitory-abietane diterpenoids, 7β-hydroxy-20-deoxo-rosmaquinone (1) and 7β-methoxy-20-deoxo-rosmanol (2), along with six known components, carnosol (3), 7α-methoxyrosmanol (4), 7β-methoxyrosmanol (5), 12-methoxy-canosic acid (6), rosmanol (7), and rosmadial (8). Compounds 1–8 inhibited DGAT1 activity, with the IC50 values ranging from 39.5 ± 0.6 to 144.2 ± 3.1 μM. In particular, carnosol (3), which is one of the major compounds of MeOH-soluble extract of R. officinalis exhibits inhibition of de novo intracellular triacylglycerol synthesis in human hepatocyte HepG2 cells. 相似文献
82.
83.
Doil Park Ji Hoon Jung Hyun Min Ko Wona Jee Hyungsuk Kim Hyeung-Jin Jang 《International journal of molecular sciences》2022,23(23)
Colorectal cancer cell (CRC) is the fourth most common cancer in the world. There are several chemotherapy drugs available for its treatment, though they have side effects. Cycloastragenol (CY) is a compound from Astragalus membranaceus (Fisch.) Bge known to be effective in aging, anti-inflammatory, anticancer, and anti-heart failure treatments. Although many studies have demonstrated the functions of CY in cancer cells, no studies have shown the effects of p53 in colon cancer cells. In this study, we found that CY reduces the viability of colon cancer cells in p53 wild-type cells compared to p53 null cells and HT29. Furthermore, CY induces apoptosis by p53 activation in a dose- and time-dependent manner. And it was confirmed that it affects the L5 gene related to p53. Additionally, CY enhanced p53 expression compared to when either doxorubicin or 5-FU was used alone. Altogether, our findings suggest that CY induces apoptosis via p53 activation and inhibits the proliferation of colon cancer cells. In addition, apoptosis occurs in colon cancer cells due to other factors. Moreover, CY is expected to have a combined effect when used together with existing treatments for colon cancer in the future. 相似文献
84.
Seung-Wook Jee Chun-Ha Lee Si-Kuk Kim Jae-Jin Lee Phil-Young Kim 《Fire Technology》2014,50(3):805-822
Many countries use conventional fire alarm control panels (FACPs) and conventional detectors as fire alarm systems (FASs) because of economic advantages. This study analyzes several problems with conventional FASs and describes an advanced FAS, the traceable FAS, that we developed to solve these problems. The traceable FAS can trace the exact location of a fire, can detect multiple fires that occur simultaneously, and can be used with conventional detectors without disrupting the other detectors operation. The traceable FAS consists of a traceable FACP based on the conventional FACP and a traceable heat detector based on the rate-of-rise spot-type conventional heat detector. The new system offers traceability in addition to all the features of the conventional FAS. The traceable FACP has 40 zones; one zone can connect up to 20 traceable heat detectors. Thus, this FACP can connect up to 800 traceable heat detectors, all of which can detect and trace exact fire locations in sequence. Furthermore, the traceable FACP can be used with both traceable heat detectors and conventional heat detectors in the same zone. Even if one detector (either traceable heat detector or conventional heat detector) detects a fire first, other traceable heat detectors in the same zone can also detect it and display the results on the traceable FACP. Prototypes of the traceable FACP and traceable heat detector (rate-of-rise spot-type) have officially received model approvals for use in South Korea. Conventional FASs can be upgraded to traceable FASs simply by changing to the traceable FACP and traceable heat detectors, without any rewiring. 相似文献
85.
Soo Jeong Kim Kyung Jun Gil HyungSeok Kim Sang Boem Lim Jee‐in Kim 《Computer Animation and Virtual Worlds》2010,21(5):531-543
In this research, we propose a method to adapt the interfaces and interaction processes of heterogeneous devices. The proposed method models the interaction capability of the devices. The interaction is modeled by categorizing elementary actions and measuring its effect in semantic behaviors. With this model, an interaction process can be modified to a given device by changing sequence of elementary actions for each behavior. In the pilot test, we showed the possibility of interaction adaptation for different situations. With the proposed adaptation mechanism, interface and interaction can be modeled for the device independently and can be transferred over different interaction environments. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
86.
A triple-band coplanar waveguide (CPW)-fed LI-shaped monopole antenna is proposed. The antenna is composed of an I-shaped monopole and a meandered L-shaped one. The dimensions of the design are 29 times 28 mm which are 0.077 lambda times 0.075 lambda in terms of the lowest operating frequency of 800 MHz. The antenna operation presents attractive characteristics, each monopole is independently optimised to the resonant frequency and the impedance bandwidth without affecting those of other bands. The antenna shows improved radiation efficiency of individual monopoles for a global system for mobile communication, personal communication systems, digital communication systems, and wireless code division multiple access applications. 相似文献
87.
Microvias of 50 μm diameter in a Si chip were filled with Zn or Sn-Zn to form through-silicon vias by means of an electroplating/reflow process
or a dipping method. In the case of the electroplating/reflow process, Zn was electroplated on a Cu seed layer in via holes,
and a reflow was then performed to fill the via holes with the electroplated Zn. In the case of the dipping method, Zn via-filling
and Sn-Zn via-filling were performed by dipping a via hole specimen into a molten bath of Zn or Sn-Zn. A filling pressure
greater than 3 MPa during the via-filling is essential for ensuring that the via holes are completely filled with Zn or Sn-Zn
and for preventing voids from being trapped in the vias. The melting temperature and electrical conductivity of the Sn-Zn
alloys increases almost linearly with the content of Zn, implying that the thermal and electrical properties of the Sn-Zn
vias can be easily controlled by varying the composition of the Sn-Zn vias. A chip-stack specimen was fabricated by flip-chip
bonding of three chips with Zn vias. 相似文献
88.
89.
Hong-Fu Zhi Mengyun Jiang Heng Zhang Qiaoshi An Hai-Rui Bai Min Hun Jee Han Young Woo Danwei Li Xuebin Huang Jin-Liang Wang 《Advanced functional materials》2023,33(25):2300878
All-small-molecule organic solar cells (ASM-OSCs) are challenging for their inadequate efficiency and device stability due to their more susceptive morphology. Herein, a family of isomeric small molecule donors (SMDs) is synthesized based on the benzodithiophene–terthiophene core with linear, 1st carbon, and 2nd carbon position branched butyl-based rhodanine for ASM-OSCs, respectively. The single crystal of thiophene-substituted model T-s-Bu forms a more compact intermolecular packing with herringbone structure than slip-layered packing-based T-n-Bu and T-i-Bu . SM-i-Bu and SM-s-Bu show slightly blue-shifted absorption and deepened HOMO levels in the neat film compared to SM-n-Bu . SM-s-Bu:BO-4Cl blend films have distinct face-on packing orientations and suitable fibrous phase separation along with more apparent microcrystals. Finally, SM-s-Bu : BO-4Cl -based device yields an improved power conversion efficiency of 16.06% compared to 15.12% and 8.22% for SM-n-Bu : BO-4Cl and SM-i-Bu : BO-4Cl , which is one of the top-ranked results for BTR-series SMDs in binary ASM-OSCs. More importantly, the excellent storage stability with a T80 lifetime of over 1700 h and decent thermal stability is realized in SM-s-Bu : BO-4Cl . This work highlights that the isomeric terminal alkyl with a branching point directly connected to the backbone for SMDs is a promising strategy for improving the crystal packing and film morphology and achieving highly efficient and stable ASM-OSCs. 相似文献
90.
Jee Yun Jung Sang-In Lee Mohammad Faisal Hayoung Kim Young-Su Lee Jin-Yoo Suh Jae-Hyeok Shim Joo-Youl Huh Young Whan Cho 《International Journal of Hydrogen Energy》2021,46(37):19478-19485
This paper discusses the effect of AB2 (Ti(Cr, Fe)2) phase on the hydrogenation properties of a Ti–Fe–Cr alloy system. Five Ti–Fe–Cr based alloys were fabricated by varying the Cr content. The microstructural analysis results revealed that the fraction of the Ti(Cr, Fe)2 phase increased with the increasing Cr content. The first hydrogenation test results indicated that all the alloys could absorb a significant amount of hydrogen at room temperature (30 °C) without a separate activation process. This behavior improved when the Ti(Cr, Fe)2 phase existed in the AB phase; the kinetics of the first hydrogenation tended to increase with the fraction of Ti(Cr, Fe)2 phase. The enhancement in the first hydrogenation kinetics of the Ti–Fe–Cr based alloys was attributed to the synergetic effect of the interface between the AB and Ti(Cr, Fe)2 phases and the inherent fast hydrogenation of the Ti(Cr, Fe)2 phase. However, the total hydrogen storage capacity decreased when the fraction of Ti(Cr, Fe)2 phase increased. 相似文献