著者
Sorapong PAVASUPREE Supachai NGAMSINLAPASATHIAN Yoshikazu SUZUKI Susumu YOSHIKAWA
出版者
The Japan Society of Mechanical Engineers
雑誌
Journal of Solid Mechanics and Materials Engineering (ISSN:18809871)
巻号頁・発行日
vol.1, no.4, pp.459-468, 2007 (Released:2007-04-27)
参考文献数
29
被引用文献数
2 2

This article has been found to be a duplicate publication of their article on another journal, and thus retracted by the Editor.
著者
Yoshikazu SUZUKI Tadashi KAMIKAWA Noboru YAMAZAKI
出版者
Japanese Heart Journal Association
雑誌
Japanese Heart Journal (ISSN:00214868)
巻号頁・発行日
vol.22, no.2, pp.219-225, 1981 (Released:2008-12-09)
参考文献数
23
被引用文献数
7 12

The effect of L-carnitine on cardiac hemodynamics was evaluated in normal closed chest dogs. Extracorporeal circulation was produced to measure coronary blood flow in closed chest dogs. Coronay venous blood was introduced to the extracorporeal circuit through a polyethylene catheter wedged into the coronay sinus under fluoroscopic control and was returned to the animal through the left jugular vein. L-carnitine was infused intravenously at a constant rate of 80mg/Kg/min for 8min. Hemodynamic responses appeared within 1 to 3min of carnitine infusion and peak effects were observed nearly after 5min. Peak effects on cardiac hemodynamics after 5 to 8min of carnitine infusion were as follows. Heart rate decreased by 17% from control (p<0.05). Aortic and left ventricular pressure increased by 20% (p<0.05 and p<0.01 respectively) and peak positive left ventricular dp/dt increased by 35% (p<0.01), the mean rate pressure product as the index of myocardial oxygen consumption remained unchanged. Coronary blood flow increased by 60% (p<0.001) and coronary vascular resistance decreased by 25% (p<0.01). As the infusion of carnitine was discontinued, the effects promptly disappeared. These data suggest that L-carnitine has direct vasodilating and positive inotropic effects on cardiovascular system.
著者
YOSHIKAZU SUZUKI TADASHI KAMIKAWA NOBORU YAMAZAKI
出版者
日本循環器学会
雑誌
JAPANESE CIRCULATION JOURNAL (ISSN:00471828)
巻号頁・発行日
vol.45, no.5, pp.552-559, 1981-05-20 (Released:2008-04-14)
参考文献数
38
被引用文献数
12 18

The effects of L-carnitine on ventricular arrhythmias were evaluated in dogs with acute myocardial ischemia and a supplement of excess free fatty acids (FFA). Acute myocardial ischemia was induced by ligation of left anterior descending coronary artery. After 80 minutes of coronary occlusion, high plasma FFA was induced by intravenous injection of heparin 200 u/kg and Intralipid(R) 5 ml/kg as a bolus. After additional 60 minutes, beating hearts were removed from animals and tissue levels of free carnitine, short and long chain acyl carnitine, FFA and adenosine triphosphate (ATP) were determined. L-carnitine 100 mg/kg was administered intravenously 5 minutes before coronary artery ligation. Electrocardiograms were recorded continuously by a Holter electrocardiographic recorder during the experiment and ventricular arrhythmias were quantified by an arbitrary scoring system. In ischemic and excess FFA supplemented myocardium, free carnitine and ATP decreased, whereas long chain acyl carnitine and FFA increased. And these metabolic changes tended to be reduced by L-carnitine. Pretreatment of L-carnitine also reduced the grade of ventricular arrhythmias induced both by acute myocardial ischemia and by supplement of excess FFA. These results suggest that the administration of L-carnitine may be beneficial to prevent serious arrhythmias in ischemic heart disease, presumably by restoring the impaired FFA oxidation.
著者
Yasunori NISHIKAWA Sogo SAYAMA Yoshinobu UEDA Yoshikazu SUZUKI
出版者
The Iron and Steel Institute of Japan
雑誌
Transactions of the Iron and Steel Institute of Japan (ISSN:00211583)
巻号頁・発行日
vol.23, no.8, pp.639-645, 1983 (Released:2006-09-08)
参考文献数
13
被引用文献数
1 1

The effect of K2O, Na2O and CaO on the reduction behavior of Fe2O3 was investigated. Platelets of Fe2O3 single crystals were prepared by the flux method. The size of the crystals was approx. 3mm in width and 0.3mm in thickness. For the reaction of Fe2O3 with K2O, Na2O, and CaO, small amounts of each carbonate powder were placed on the flat plane (0001) of Fe2O3 and heated at 1100-1300°C in the air. It was confirmed by EPMA that the reaction products with those substances were formed on some parts of the Fe2O3 crystal. The crystals were reduced at 750°C in CO and H2 streams, and the surface structures were observed by SEM.The results obtained were as follows. When alkaline metals (as Na2O, K2O) were present in Fe2O3, the abnormal swelling took place during the reduction. It was considered that the swelling was caused by (1) the cracking of the crystal at the early stage of the reduction, (2) the fibrous iron formation and (3) the carbon deposition on the reduced iron. The fibrous iron formation was also observed in the grain boundary of calcium ferrite. The reduction with a glassy slag (SiO2-Al2O2-CaO) was also investigated and no swelling phenomenon was shown.