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排序方式: 共有450条查询结果,搜索用时 15 毫秒
31.
H Kobayashi K Kusakabe M Momose T Okawa S Inoue N Iguchi S Hosoda 《Canadian Metallurgical Quarterly》1998,39(7):1117-1122
The purpose of this study was to clarify the possibility of simultaneous evaluation of myocardial perfusion and fatty acid metabolism using a single injection of 123I-beta-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) in patients with acute coronary syndromes. METHODS: Thirty patients with unstable angina pectoris (UAP group) and 15 patients with acute myocardial infarction (MI group) were studied. BMIPP dynamic SPECT was performed 2 min after the injection of BMIPP (185 MBq), and images were obtained every 3 min for 15 min with a three-head gamma camera. Conventional BMIPP SPECT was also performed 30 min after the injection. Serial BMIPP and resting 201TI images were compared. RESULTS: A 201TI-BMIPP mismatch between 30-min BMIPP and resting 201TI images was observed in 27 of 30 patients in the UAP group and 8 of 15 patients in the MI group, respectively. However, a 201TI-BMIPP mismatch between early (2-5-min) BMIPP and resting 201TI images was observed in only 2 of 30 patients in the UAP group and in only 2 of 15 patients in the MI group, respectively. The kappa statistics of tracer uptake between early BMIPP and resting 201TI images showed good concordance in UAP (kappa = 0.823) and MI (kappa = 0.765) groups, respectively. These results indicated that initial distribution of BMIPP reflects myocardial perfusion in patients with acute coronary syndromes. CONCLUSION: Myocardial perfusion and fatty acid metabolism can be evaluated simultaneously using a single injection of BMIPP, when images are taken soon (2-5 min) and long after the injection in patients with acute coronary syndromes. 相似文献
32.
High-Temperature Active Oxidation of Chemically Vapor-Deposited Silicon Carbide in CO─CO2 Atmosphere
Takayuki Narushima Takashi Goto Yoshio Yokoyama Yasutaka Iguchi Toshio Hirai 《Journal of the American Ceramic Society》1993,76(10):2521-2524
Active oxidation behavior of CVD-SiC in CO─CO2 atmospheres was investigated using a thermogravimetric technique in the temperature range between 1823 and 1923 K. The gas pressure ratio, P CO2 / P CO , was controlled between 10−4 and 10−1 at 0.1 MPa. Active oxidation rates (mass loss rates) showed maxima at a certain value of P CO2 / P CO , ( P CO2 / P CO )* , In a P CO2 / P CO region lower than the ( P CO2 / P CO )* a carbon layer was formed on the SiC surface. In a P CO2 / P CO region higher than the ( P CO2 / P CO )* , silica particles or a porous silica layer was observed on the SiC surface. 相似文献
33.
Takayuki Sasaki Yuu Takeno Akira Kirishima Nobuaki Sato 《Journal of Nuclear Science and Technology》2013,50(2):147-151
The leaching behaviors of gamma-ray radionuclides, Cs-137, Ru-103, and Zr-95, produced by neutron irradiation of UO2/ZrO2 solid solutions, in real surface seawater were investigated under atmospheric conditions. The fraction of radionuclide inventory leached in the seawater was in the order of Cs > Ru (~U) ? Zr, indicating that the fraction was significantly affected by the chemical state of the radionuclides. However, the amount of soluble nuclides was proportional to that of uranium regardless of whether the solid solutions were prepared under an oxidative or reductive environment. A tiny fraction of Ru was filtered out by a 3 kDa nominal molecular weight cut-off filter after the 160 d leaching test, suggesting a different behavior from its ionic form, but Cs and U did not form a colloid-like species in seawater. 相似文献
34.
35.
Riehman Kara S.; Iguchi Martin Y.; Anglin M. Douglas 《Canadian Metallurgical Quarterly》2002,16(4):333
This study examined whether higher rates of depressive symptoms among amphetamine compared with cocaine users result from amphetamine use itself, polydrug use, or experiencing a major lifetime depressive episode and whether depressive symptoms among amphetamine users are more likely to persist 12 months after treatment. The association between amphetamine use and depressive symptoms disappears when controlling for polydrug use and lifetime major depressive episode. Polydrug use and lifetime depressive episode are significantly related to depressive symptoms in the year preceding treatment. Amphetamine use at intake does not predict depressive symptoms among individuals who are abstinent at follow-up, and amphetamine users are no more likely than cocaine users to report depression at a 12-month follow-up. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Norinaga Urahama Genzo Iguchi Mitsue Shimizu Kazuhiro Fujihira Shunzo Kobayashi Hisamitsu Baba 《Nicotine & tobacco research》2008,10(8):1391-1395
All forms of tobacco cause cardiovascular disease, and tobacco-related disease is a leading cause of death worldwide. Smoking oxidizes low-density lipoprotein (LDL) particles, and oxidized LDL particles are thought to play an early and critical role in atherosclerogenesis. Hyper-low-density lipoproteinemia is one of the risk factors for cardiovascular disease, but small, dense LDL particles have been associated with an increased risk for cardiovascular disease. Small, dense LDL correlates with some cardiovascular risk factors such as diabetes mellitus, hypertriglyceridemia, hypo-high-density lipoproteinemia, and hypertension. Although smoking is also a major risk factor for cardiovascular disease, the relationship between smoking and small, dense LDL particles has not been described previously. Our cross-sectional study examined this relationship in a population of 18 healthy young adult men (9 smokers and 9 never-smokers, aged 21-24 years) from the same college. Concentrations of blood lipids and the LDL migration index (LDL-MI) were examined. Although concentrations of blood lipids did not differ between smokers and never-smokers, the LDL-MI had a strong tendency to be lower in smokers. The LDL-MI is larger in the presence of a greater proportion of small, dense LDL particles. These results indicate that tobacco smoking is associated with a decrease in the proportion of small, dense LDL particles. Regardless of these surprising results, we do not recommend smoking, given that it is a major cause of cardiovascular disease. 相似文献
37.
Masahide Goto Kei Hagiwara Yoshinori Iguchi Hiroshi Ohtake Takuya Saraya Hiroshi Toshiyoshi Toshiro Hiramoto 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(3):329-333
We have developed a novel MOSFET that can transfer signals vertically without through‐silicon vias but by using a fully depleted silicon‐on‐insulator (FDSOI) structure with its source region connected to the back electrodes as well as the front ones. A prototype MOSFET fabricated using the backside anisotropic wet etching technique has confirmed that the electrical characteristics measured from the front and the back electrodes are identical. The subthreshold factor S of the prototype was found to be 64.5 mV/decade, suggesting a good switching performance. Since the double‐sided MOSFET has vertical signal‐transfer capability and excellent operating characteristics, it is expected to contribute to developing a More‐than‐Moore type device of three‐dimensional integration such as pixel‐parallel image sensors. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
38.
Purification and characterization of a protease from Pseudomonas aeruginosa grown in cutting oil 总被引:2,自引:0,他引:2
The Pseudomonas aeruginosa san-ai strain was isolated from water-soluble cutting oil used for cooling and lubrication during industrial metal-working processes. This strain, which is grown in a high alkaline (pH 10) mixture of surfactants and mineral oil, produces an extracellular proteolytic enzyme. We have purified and characterized this 18 kDa protease. The P. aeruginosa san-ai protease functions optimally at pH 9.0 and 60 degrees C. Additionally, it is a Zn-containing metalloenzyme, and its monomeric structure contains at least one disulfide bond. Because the enzyme is stable in the presence of organic solvents, it is suitable for peptide synthesis. Furthermore, the P. aeruginosa san-ai protease could be used in an intelligent drug delivery system (DDS) designed for applications in the metal industry for prevention of putrefaction of cutting oil. 相似文献
39.
Kan‐Hua Lee Kenji Araki Li Wang Nobuaki Kojima Yoshio Ohshita Masafumi Yamaguchi 《Progress in Photovoltaics: Research and Applications》2016,24(10):1310-1318
The paper presents a quantitative approach to the investigation and comparison of the material qualities of III–V on silicon (III–V/Si) solar cells by using external radiative efficiencies. We use this analysis to predict the limiting efficiencies and evaluate the criteria of material quality in order to achieve high‐efficiency III–V/Si solar cells. This result yields several implications for the design of high‐efficiency III–V/Si solar cells. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
40.
Southam AD Lange A Hines A Hill EM Katsu Y Iguchi T Tyler CR Viant MR 《Environmental science & technology》2011,45(8):3759-3767
The ability of targeted and nontargeted metabolomics to discover chronic ecotoxicological effects is largely unexplored. Fenitrothion, an organophosphate pesticide, is categorized as a "red list" pollutant, being particularly hazardous to aquatic life. It acts primarily as a cholinesterase inhibitor, but evidence suggests it can also act as an androgen receptor antagonist. Whole-organism fenitrothion-induced toxicity is well-established, but information regarding target and off-target molecular toxicities is limited. Here we study the molecular responses of male roach ( Rutilus rutilus ) exposed to fenitrothion, including environmentally realistic concentrations, for 28 days. Acetylcholine was assessed in brain; steroid metabolism was measured in testes and plasma; and NMR and mass spectrometry-based metabolomics were conducted on testes and liver to discover off-target toxicity. O-demethylation was confirmed as a major route of pesticide degradation. Fenitrothion significantly depleted acetylcholine, confirming its primary mode of action, and 11-ketotestosterone in plasma and cortisone in testes, showing disruption of steroid metabolism. Metabolomics revealed significant perturbations to the hepatic phosphagen system and previously undocumented effects on phenylalanine metabolism in liver and testes. On the basis of several unexpected molecular responses that were opposite to the anticipated acute toxicity, we propose that chronic pesticide exposure induces an adapting phenotype in roach, which may have considerable implications for interpreting molecular biomarker responses in field-sampled fish. 相似文献