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141.
Eighteen kinds of pyrimido[5,4-d]pyrimidines together with several commercially available fluorescent compounds such as perylene, Rhodamine B, etc., were evaluated as the reagents for a peroxyoxalate chemiluminescence (CL) detection system by using a flow injection method. The peroxyoxalate CL reaction employed consists of bis(2,4,6-trichlorophenyl)oxalate, hydrogen peroxide, triethylamine, and a fluorophore. Under the conditions used, 2,6-bis[di-(2-hydroxyethyl)amino]-4,8- dipiperidinopyrimido[5,4-d]pyrimidine (Dipyridamole) and 2,4,6,8-tetrathiomorpholinopyrimido[5,4-d]pyrimidine (1i) gave very intense chemiluminescence intensities which were larger than those of any other commercially available fluorescent compounds tested (e.g., 10 times larger than that of perylene). 相似文献
142.
Radiation emitted from the shock layer generated around a hypersonic flight model is experimentally investigated by using a ballistic range (two-stage light-gas gun). A polyethylene projectile of 1.2 cm in diameter is launched in this facility at the velocity of 5 km/sec (M=15), and the emission from the induced shock layer around the projectile is observed with a spectroscope. As a result, molecular band-spectra from NO and N2 are detected along with those from carboncontaining molecules. Total emission power is measured with a diode-type powermeter. In addition, dimension effect of the flight model is theoretically and numerically examined, and a scaling law on thermochemical structure of the shock layer is developed. It shows that the thickness of thermal boundary-layer formed on the model surface does not follow the conventional scaling law based on the reaction distance and on the energy relaxation distance. Finally, the radiative field around the projectile is numerically computed, and the total power emitted from the shock layer is estimated. From the comparison between computed and measured results, the validity of the calculation model is discussed. 相似文献
143.
Ellagic Acid Suppresses ApoB Secretion and Enhances ApoA-1 Secretion from Human Hepatoma Cells,HepG2
Ayana Ieda Maki Wada Yuuki Moriyasu Yuuko Okuno Nobuhiro Zaima Tatsuya Moriyama 《Molecules (Basel, Switzerland)》2021,26(13)
The effect of ellagic acid (EA), a naturally occurring polyphenolic compound, on the secretion of apolipoproteins from human hepatocytes, HepG2, was investigated. The levels of apoB and apoA-1 secreted in the cell culture medium were determined by sandwich ELISA. EA did not affect cell viability at the tested concentrations (up to 50 µM). EA suppressed the secretion of apoB and enhanced that of apoA-1 from HepG2 cells. However, cellular apoB levels were increased, suggesting that EA inhibited the trafficking of apoB during the process of secretion. In contrast, the increase in the cellular levels of apoA-1 was consistent with its secreted levels. These results indicate that EA inhibits the secretion of apoB from hepatocytes and increases the secretion of apoA-1. Both of these effects are beneficial for lipoprotein metabolism in the prevention of lifestyle-related diseases. The detailed mechanism underlying these effects of EA on lipoprotein metabolism should be elucidated in the future, but this naturally occurring polyphenolic compound might be antihyperlipidemic. Based on these results, EA is suggested as a candidate food-derived compound for the prevention of hyperlipidemia. 相似文献
144.
Duanyang Wang Maki Nagata Masako Matsumoto Yhiya Amen Dongmei Wang Kuniyoshi Shimizu 《Molecules (Basel, Switzerland)》2022,27(18)
Hibiscus sabdariffa L. (HS) has a long history of edible and medicinal uses. In this study, the biological activities of the extracts, chromatographic fractions, and hibiscus acid obtained from HS were evaluated for their potential bioactivities. Their ability to promote extracellular matrix synthesis in skin fibroblasts was evaluated by enzyme-linked immunosorbent assays. Their anti-inflammatory activity was evaluated in a nitric oxide (NO)–Griess inflammatory experiment. Furthermore, hibiscus acid was found to have a strong anti-oxidative stress effect through the establishment of an oxidative stress model induced by hydrogen peroxide. Several assays indicated that hibiscus acid treatment can effectively reduce extracellular adenosine triphosphate (ATP) secretion and carbonyl protein production, as well as maintain a high level of reduced/oxidized glutathione (GSH/GSSG) in skin cells, thus providing a possible mechanism by which hibiscus acid can counter antioxidative stress. The present study is the first to explore the reversing skin aging potential and the contributory component of HS. 相似文献
145.
V. Henriques U. Klausen J. Race K. L. Zirm J. Benedict W. Zimmermann J. Robert S. W. Cole S. L. Leiboff B. S. Kahn B. Matsumoto L. Ambard F. Schmid T. Teorell S. Balachowski B. Bruns A. Fujita S. Kasahara F. Serio S. Fiandaca K. Lang O. Manasse H. Müller H. v. Pechmann G. Schmidt R. Willstätter H. Kraut O. Erbacher J. Sacks A. C. Jvy J. P. Burgess und J. E. Vandolah 《Fresenius' Journal of Analytical Chemistry》1933,93(1-2):64-80
Ohne Zusammenfassung 相似文献
146.
Eno S Auchincloss P Blanis D Bodek A Budd H Fry CA Harada H Ho YH Kim YK Kumita T Mori T Olsen SL Shaw NM Sill A Thorndike EH Ueno K Zheng HW Imlay R Kirk P Lim J McNeil RR Metcalf W Myung SS Cheng CP Gu P Li J Li YK Mao ZP Xu YT Zhu YC Abashian A Gotow K Hu KP Low EH Mattson ME Piilonen L Sterner KL Lusin S Rosenfeld C Wang AT Wilson S Frautschi M Kagan H Kass R Trahern CG Breedon RE Kim GN Ko W Lander RL Maeshima K Malchow RL Smith JR Stuart D Williams MC Abe K Fujii Y Higashi Y Kim SK 《Physical review letters》1989,63(18):1910-1913
147.
148.
Stuart D Breedon RE Kim GN Ko W Lander RL Maeshima K Malchow RL Smith JR Imlay R Kirk P Lim J McNeil RR Metcalf W Myung SS Cheng CP Gu P Li J Li YK Ye MH Zhu YC Abashian A Gotow K Hu KP Low EH Mattson ME Piilonen L Sterner KL Lusin S Rosenfeld C Wang AT Wilson S Frautschi M Kagan H Kass R Trahern CG Abe K Fujii Y Higashi Y Kim SK Kurihara Y Maki A Nozaki T Omori T Sagawa H Sakai Y Sugimoto Y Takaiwa Y Terada S Walker R Kajino F Perticone D Poling R Thomas T Ishi Y Miyano K Miyata H Sasaki T 《Physical review letters》1990,64(9):983-986
149.
Inoue Kazumasa Sahoo Sarata Kumar Veerasamy Nimelan Kasahara Shogo Fukushi Masahiro 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1423-1434
Journal of Radioanalytical and Nuclear Chemistry - Absorbed dose rates in air for 20 residential areas in Odisha were measured using a vehicle-mounted NaI(Tl) scintillation spectrometer. The... 相似文献
150.
Controlled chemical reaction of single trans-2-butene molecules on the Pd(110) surface was realized by dosing tunneling electrons from the tip of a scanning tunneling microscope at 4.7 K. The reaction product was identified as a 1,3-butadiene molecule by inelastic electron tunneling spectroscopy. Threshold voltage for the reaction is approximately 365 mV, which coincides with the vibrational excitation of the C-H stretching mode. The reaction was ascertained to be caused by C-H bond dissociation by multiple vibrational excitations of the C-H stretching mode via inelastic electron tunneling process. 相似文献