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991.
Takahiko Sakamoto Masahiro Endo Hiroshi Nishida Yasuko Tomizawa Shin-ichiro Kihara Hitoshi Koyanagi 《General thoracic and cardiovascular surgery》1998,46(10):966-970
We evaluated the coronary artery bypass grafting (CABG) for the cases which were not amenable to preoperative left ventriculograms (LVG). Between June 1970 and March 1996, we had 2045 cases of isolated CABG, and 52 cases of which were not amenable to preoperative LVG. The reasons of no preoperative LVG were during cardiopulmonary resuscitation (CPR) in 4 cases, shock state in 14, NYHA class IV or CCS class IV in 26, angina attack after coronary angiography in 3 and so on. Preoperative diagnoses were acute myocardial infarction in 28, angina after infarction in 13, unstable angina in 9 and effort angina in 2. Preoperative conditions were reoperation in 6, insertion of intra-aortic balloon pumping in 46, chronic renal failure in 15 (hemodialysis in 4) and arrythmia (VT or Vf) in 12. Concerning the coronary lesions, left main trunk and tripple vessel diseases occupied 75% of all. Surgical deaths were 5 cases (9.6%) and hospital deaths were 4 cases (7.7%). The all cases which needed preoperative CPR were died with brain injury. The result of the cases which were not amenable to preoperative LVG were worse than the cases with ischmic cardiomyopathies. In conclusion, no preoperative LVG is one of the highest risk factors of all. 相似文献
992.
Yoshihiko Yoshii Motohiro Satou Tetsuya Yamamoto Yuzou Yamada Akio Hyodo Tadao Nose Hiromi Ishikawa Rokuro Hatakeyama 《European journal of nuclear medicine and molecular imaging》1993,20(1):39-45
The aim of this study was to characterise brain tumour type and treatment response in relation to the uptake of thallium-201.201Tl single photon emission tomography (SPET) was performed in 58 patients with brain tumours. Fifty-six patients were utilised for the statistical comparison of the early and delayed201Tl indices expressed as the ratio of tumour to contralateral cerebral hemisphere uptake. The retention index of201Tl in the tumour tissue calculated from the early and delayed scans was also analysed. Furthermore, in 56 patients with 58 brain tumours, a comparison was made of the diagnostic value of high201Tl uptake and gadolinium diethylene triamine penta-acetic acid (Gd-DTPA) enhancement on MRI scans. Although high201Tl uptake was observed in viable malignant gliomas, brain metastases, meningiomas and malignant teratoma, the viable malignant gliomas could not be differentiated from brain metastases and extracerebral tumours by means of201Tl indices.201Tl SPET failed to diagnose a viable ring-enhanced tumour with a thin rim and small tumours of less than 1.5 cm in diameter visualised by Gd-DTPA-enhanced MRI. In spite of this,201Tl SPET appears to be effective for determination of the malignant viability of tumours 相似文献
993.
Masatoshi Kudo MD David R. Vera PhD Robert C. Stadalnik MD Carlos O. Esquivel MD PhD Walter L. Trudeau MD Katsuji Ikekubo MD Akio Todo MD 《Digestive diseases and sciences》1993,38(12):2183-2188
Technetium-99m-galactosyl-neoglycoalbumin (TcNGA) is a synthetic radiolabeled ligand specific for hepatic binding protein (HBP), a receptor that resides exclusively on hepatocytes.In vivo measurement of receptor concentration was obtained via kinetic analysis of liver and blood time-activity data obtained during the hepatic clearance of intravenously administered TcNGA. The purpose of this study was to assess receptor concentration as a measure of the functioning hepatocyte mass. Therefore, TcNGA and dualinjection indocyanine green maximal removal rate (ICG Rmax) studies were performed on nine patients with hepatic cirrhosis associated or not with hepatocellular carcinoma. Receptor concentration was compared with ICG Rmax, which is a validated method for the estimation of the functioning hepatocyte mass. The correlation coefficient was 0.76 (P=0.017). It is concluded that HBP concentration ([HPB]o) as measured by functional imaging is a measure of functioning hepatocyte mass. This implies that measurement of an individual's receptor concentration by using nuclear medicine techniques provides an objective index of hepatic functional mass and supports attempts to rigorously evaluate [HBP]o for its clinical efficacy. 相似文献
994.
Kazuhiro Ashida Yukihiko Momiyama Zahi A Fayad Nobukiyo Tanaka Ryuichi Kato Hiroaki Taniguchi Reiko Ohmori Teruyoshi Kihara Akira Kameyama Masayoshi Nagata Haruo Nakamura Fumitaka Ohsuzu 《Journal of cardiovascular magnetic resonance》2007,9(6):855-861
The association between coronary artery disease (CAD) and thoracic aortic plaques has often been reported using transesophageal echocardiography. However, studies showing the association between CAD and abdominal aortic plaques are scarce. CMR can visualize plaques in both the thoracic and abdominal aortas. Using CMR, we investigated the associations of thoracic and abdominal aortic plaques with the presence and extent of coronary artery stenosis in 146 patients undergoing coronary angiography, of whom 108 had CAD. The prevalence of thoracic and abdominal aortic plaques was higher in patients with CAD than in those without CAD (73% and 94% vs. 32% and 79%, p < 0.025). Stepwise increases in the prevalence and extents of both thoracic and abdominal plaques were found depending on the number of stenotic coronary vessels. Plaque extent in the thoracic aorta correlated with the numbers of > 50% and > 25% stenotic coronary segments (rs = 0.30 and 0.41). Plaque extent in the abdominal aorta also correlated with the numbers of > 50% and > 25% stenotic segments (rs = 0.40 and 0.44). Notably, the total plaque extent in the aortas correlated best with the numbers of > 50% and > 25% stenotic coronary segments (rs = 0.41 and 0.49, p < 0.001), and this factor was found to be the best predictor for the presence of CAD by the receiver-operating-characteristics curve analysis. Thus, the total plaque extent in the aortas was found to be more closely associated with the presence and extent of coronary stenosis than the thoracic or abdominal aortic plaque extent. 相似文献
995.
Beneficial effects of pioglitazone on left ventricular hypertrophy in genetically hypertensive rats.
Tomoko Shinzato Yusuke Ohya Minori Nakamoto Akio Ishida Shuichi Takishita 《Hypertension research》2007,30(9):863-873
Beneficial effects of thiazolidinediones, peroxisome proliferator-activated receptor gamma (PPARgamma) agonists, on cardiovascular injuries have been reported. However, the effects of these agonists on left ventricular (LV) hypertrophy have not been clarified. To investigate whether pioglitazone improves LV hypertrophy, we used 32-week-old stroke-prone spontaneously hypertensive rats (SHR-SP) that had been treated or not treated with pioglitazone (10 mg/kg/day) for 8 weeks, and Wistar Kyoto rats (WKY). We evaluated LV geometry by echocardiography; myocyte hypertrophy, tissue fibrosis, and appearance of myofibroblasts by histological examination; mRNA expression by real-time polymerase chain reaction (PCR); protein expression by Western blot; activities of matrix metalloproteinase (MMP) by zymography; and production of reactive oxygen species (ROS) by electron spin resonance spectroscopy or thiobarbituric acid reactive substances (TBARS). SHR-SP showed concentric hypertrophy of the LV, but WKY did not. The myocyte diameter, fraction of tissue fibrosis, and number of myofibroblasts were greater in SHR-SP. mRNA expressions of collagen type I and type III, tissue growth factor (TGF)-beta1, and brain natriuretic peptide (BNP); protein expression of connective tissue growth factor (CTGF); activities of MMP2 and MMP9; and ROS were increased in SHR-SP. Pioglitazone did not decrease blood pressure, but partially normalized LV geometry in addition to decreasing myocyte diameter, interstitial fibrosis and number of myofibroblasts; mRNA levels of collagen type I and BNP; MMP2 activity; and protein level of CTGF. However, the mRNA level of collagen type III and TGF-beta1, MMP9 activity, and ROS production were not improved. In conclusion, pioglitazone reversed the concentric LV remodeling independently from blood pressure or oxidative stress in chronic hypertension. 相似文献
996.
997.
Yoshikuni YOGI Akio TSUCHIMOCHI Jiro KIKUCHI Hiromichi TAKE Toshiaki SETOGUCHI 《Digestive endoscopy》1998,10(3):244-247
Abstract: We report herein a case of a 13-year-old Japanese boy with symptomatic cholelithiasis. The patient was admitted to our hospital for investigation of right hypochondrial pain. An abdominal plain X-ray film showed calcifications at the right upper quadrant of the abdomen. Ultrasonography and computed tomography of the abdomen revealed several stones in the gallbladder. He underwent laparoscopic cholecystectomy under a diagnosis of idiopathic and radiopaque gallstones. Twelve calcium bilirubinate stones were found in the gallbladder. Reports of laparoscopic cholecystectomy in children are rare, and only 29 cases of 15 years of age or younger have been reported in Japan. This paper presents an additional case report of laparoscopic cholecystectomy in a pediatric patient, body weight 32 kg, with symptomatic and pigment gallstones. We believe that laparoscopic cholecystectomy should be the procedure of choice for removal of the gallbladder even in children. 相似文献
998.
999.
Tadashi Hisamitsu Masahiko Fujishita Shunji Asamoto Akio Nakamura Chifuyu Takeshige 《Brain research bulletin》1992,29(2):141-145
We previously found that the center of animal hypnosis production in the rabbit is located around the locus ceruleus and brachium conjunctivum (LC-BC) of the brainstem. The involvement of serotonergic neurons in this area of animal hypnosis was investigated by microinjection of serotonin into these regions. The duration of animal hypnosis (DAH) induced by inversion was diminished to about 65% of the controls by serotonin microinjection into the LC-BC and microinjection of methysergide prolonged the DAH to 3.2 times that of the controls. Flexor muscle contraction (CFM) of the upper extremities induced by electrical stimulation of the motor cortex was enhanced by serotonin. In normal rabbits, hard pressure on the ear base or the lumbar paravertebral area reduced CFM and this effect was partially antagonized by serotonin microinjected into the LC-BC. The results suggest that serotonergic neurons in the LC-BC modulate animal hypnosis. 相似文献
1000.
Effects of paraquat on mitochondrial electron transport system and catecholamine contents in rat brain 总被引:9,自引:0,他引:9
Toshinaga Tawara Tetsuhito Fukushima Nobumasa Hojo Akio Isobe Kuninori Shiwaku Tomoichi Setogawa Yosuke Yamane 《Archives of toxicology》1996,70(9):585-589
The effects of paraquat on rat brain were studied. Activities of complex I (NADH: ubiquinone oxidoreductase) in mitochondrial
electron transport system, lipid peroxidation and the amount of catecholamines in rat brain were measured after acute paraquat
exposure. Complex I activities were significantly lower and lipid peroxides were higher in the brains of a paraquat-treated
group than in those of a control group. Lipid peroxide in rat serum, however, did not increase after paraquat exposure. A
study of the time dependency of paraquat effects disclosed that mitochondrial complex I activities in rat brain as well as
those in rat lung and liver gradually decreased prior to the appearance of respiratory dysfunction. As compared to controls,
the dopamine in rat striatum was significantly lower in the paraquat-treated group. These results suggest that paraquat after
crossing the blood-brain barrier might be reduced to the radical in rat brain, which may damage the brain tissue, especially
dopaminergic neurons in striatum. We therefore propose that cerebral damage should be taken into consideration on paraquat
exposure. Patients may therefore need to be followed up after exposure to high doses of paraquat.
Received: 19 June 1995/Accepted: 18 January 1996 相似文献