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961.
Lee SS Riduan SN Erathodiyil N Lim J Cheong JL Cha J Han Y Ying JY 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(24):7394-7403
γ-Fe(2)O(3) nanoparticles were formed inside the cage-like pores of mesocellular foam (MCF). These magnetic nanoparticles showed a uniform size distribution that could be easily controlled by the MCF pore size, as well as by the hydrocarbon chain length used for MCF surface modification. Throughout the entrapment process, the pore structure and surface area of the MCF remained intact. The resulting magnetic MCF facilitated the immobilization of biocatalysts, homogeneous catalysts, and nanoclusters. Moreover, the MCF allowed for facile catalyst recovery by using a simple magnet. The supported catalysts exhibited excellent catalytic efficiencies that were comparable to their homogeneous counterparts. 相似文献
962.
Jung IH Lee YH Yoo JY Jeong SJ Sonn SK Park JG Ryu KH Lee BY Han HY Lee SY Kim DY Lee H Oh GT 《Experimental & molecular medicine》2012,44(5):311-318
In this study, the synergistic effect of 6-[4-(1-cyclohexyl- 1H-tetrazol-5-yl) butoxy]-3,4-dihydro-2(1H )-quinolinone (cilostazol) and Ginkgo biloba extract (GbE) was examined in apolipoprotein E (ApoE) null mice. Co-treatment with GbE and cilostazol synergistically decreased reactive oxygen species (ROS) production in ApoE null mice fed a high-fat diet. Co-treatment resulted in a significantly decreased atherosclerotic lesion area compared to untreated ApoE mice. The inflammatory cytokines and adhesion molecules such as monocyte chemoattractant-1 (MCP-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and VCAM-1 which can initiate atherosclerosis were significantly reduced by the co-treatment of cilostazol with GbE. Further, the infiltration of macrophages into the intima was decreased by co-treatment. These results suggest that co-treatment of GbE with cilostazol has a more potent anti-atherosclerotic effect than treatment with cilostazol alone in hyperlipidemic ApoE null mice and could be a valuable therapeutic strategy for the treatment of atherosclerosis. 相似文献
963.
This paper presents an analytical solution to estimate the liquid film thickness in two-phase annular flow through a circular pipe using electrical resistance tomography. Gas–liquid flow with circular gas core surrounded by a liquid film is considered. Conformal mapping is employed to obtain the analytic solution for annular flow with an eccentric circular gas core. The liquid film thickness for an arbitrary annular flow is estimated by comparing the resistance values for concentric and eccentric annular flows. The film thickness estimation has a good performance when the normalized distance between the gas core center and the flow center is less than 0.2 and the void fraction is greater than 0.4, the estimated error of the normalized thickness is less than 0.04. 相似文献
964.
965.
Choi SK Oh HM Lee SK Jeong DG Ryu SE Son KH Han DC Sung ND Baek NI Kwon BM 《Natural product research》2006,20(4):341-346
Two biflavonoids, ginkgetin (1) and sciadopitysin (2), were isolated from the MeOH extract of the young branches of Taxus cuspidata, which inhibited phosphatase of regenerating liver-3 (PRL-3) with IC50 values of 25.8 and 46.2 microM, respectively. This is the first report on PRL-3 inhibitors, isolated from natural sources. 相似文献
966.
The 532 or 355 nm laser-induced photoisomerization of allylic alcohols to aldehydes catalyzed by [Fe(3)(CO)(12)] or [Fe(CO)(4)PPh(3)] in hexane was investigated. The Fourier transform infrared (FTIR) absorption spectra of iron-carbonyl intermediate species such as [Fe(CO)(5)], [Fe(CO)(4)(R-C(3)H(4)OH)], and more importantly the pi-allyl iron-carbonyl hydride species [FeH(CO)(3)(R-C(3)H(3)OH)] (R=H, Me, Ph) were recorded during the catalytic process using [Fe(3)(CO)(12)] as the catalytic precursor. When [Fe(CO)(4)PPh(3)] was photolyzed with 355 nm, [FeH(CO)(3)(R-C(3)H(3)OH)] was also generated indicating the common occurrence of the species in these two systems. The pi-allyl hydride species is long believed to be a key intermediates and its detection here lends support to the pi-allyl mechanism of the photoisomerization of allyl alcohols. 相似文献
967.
Solvation and transfer dynamics of photoinjected electrons in thin ice film coadsorbed with CFCl3 were investigated by two-photon photoemission spectroscopy. Water molecules were found to solvate the photoinjected electrons within the first several hundred femtoseconds, thus stabilizing the electron with a lifetime of ca. 120 fs for 5 ML ice film grown on Ag(111). The significant lifetime decrease upon adsorption of CFCl3 on the ice film was attributed to dissociative electron transfer of the solvated electron based on the observed scission of the C-Cl bonds. Furthermore, the photodissociation rate of CFCl3 adsorbed directly on Ag(111) was observed to increase drastically owing to the transfer of the solvated electron when ice film was overlaid. 相似文献
968.
New tricyclic geldanamycin analogues from an engineered strain of Streptomyces hygroscopicus JCM4427
Two tricyclic geldanamycin analogues, DHQ5 (1) and DHQ6 (2), were produced by a combinatorial mutant (AC15) contained a site-directed mutagenesis on the geldanamycin polyketide synthase (PKS) gene with inactivation of the post-PKS tailoring genes (gel7) of Streptomyces hygroscopicus JCM4427. The structural diversity of tricyclic geldanamycin analogues is due to the formation of unusual additional rings, which are formed by alkylation of the C-21 position by C-12 in DHQ5 (1) and by electrophilic addition of the C-15 hydroxyl group to the double bond (C-8-C-9), which leads to the migration of the double bond (to C-7-C-8) and the elimination of a carbamoyloxy group in DHQ6 (2). 相似文献
969.
Kim MJ Lee SJ Lee JH Kim SH Chun HK Kim SH Lim HK Yun SH 《Magnetic resonance imaging》2012,30(6):848-853
Introduction
To diagnose rectal cancer and monitor treatment response after preoperative concurrent chemoradiotherapy (CCRT) in rectal cancer patients using proton-1 magnetic resonance spectroscopy (1H-MRS).Materials and Methods
We enrolled 134 rectal cancer patients before treatment, of whom 34 underwent preoperative CCRT and follow-up MR spectroscopy before surgery. 1H-MRS was performed using a six-channel phased-array coil at 3.0 T. We evaluated the presence of a choline peak at 3.2 ppm, and lipid peaks at 0.9 and 1.3 ppm, and glutamine and glutamate peaks at 2.1-2.3 and 2.7 ppm seen at two TEs (40 and 135 ms). We divided MR spectra patterns into two groups (A and B).Results
A choline peak at 3.2 ppm seen in both TEs was characteristic for rectal cancer before treatment. Of 103 patients, 55 (53%) showed an elevated choline peak before treatment (type A). Type A spectra were seen in 68% of patients (23/34) before preoperative CCRT. After CCRT, the choline peak disappeared, resulting in only the lipid peak at 1.3 ppm (type B) in 97% of patients (33/34).Discussion
We optimized a localized in vivo1H-MRS method for detection of rectal adenocarcinoma and monitoring treatment response after preoperative CCRT. The method appears to be a promising and feasible noninvasive modality. 相似文献970.
Jae-Seong Park Joon-Woo Jeon Chang-Hyung Lee Chang-Hoon Choi Sungho Jin Tae-Yeon Seong 《Superlattices and Microstructures》2012
A Ru capping layer is employed to improve the thermal stability of Ag ohmic reflectors for high-power GaN-based light-emitting diodes (LEDs). The 20-nm-thick Ru capping layer is shown to be fairly effective in suppressing agglomeration by forming RuO2. The Ag/Ru contacts exhibit specific contact resistance of 8.1 × 10−5 Ω cm2 and reflectance of ∼89% at a wavelength of 450 nm when annealed at 500 °C for 1 min, which are much better than that of Ag only contacts. Blue LEDs fabricated with the 500 °C-annealed Ag/Ru contacts give a forward voltage of 2.98 V at an injection current of 20 mA, which is lower than that (3.02 V) of LEDs with the 500 °C-annealed Ag only contacts. LEDs with the 500 °C-annealed Ag/Ru contacts show 25% higher output power (at 20 mA) than LEDs with the 500 °C-annealed Ag only contacts. X-ray photoemission spectroscopy examinations are performed to describe the improved electrical performance of the Ag/Ru contacts. 相似文献