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11.
Shohei Takeda Yutaka Inada Yoshiki Ozawa Narue Nakamizo Teruaki Tomaru 《Journal of anesthesia》1995,9(2):176-181
The cardiovascular responses to an infusion of KRN2391, a potassium channel opener, was studied in halothane-anesthetized
dogs. Intravenous administration of KRN2391 at 1.0 and 5.0 μg·kg−1·min−1 for 60 min produced dose-dependent decreases in mean arterial pressure (MAP) and systemic vascular resistance (SVR) associated
with dose-dependent increases in the cardiac index (CI) and stroke volume index (SVI) but was not accompanied by an increase
in heart rate (HR). The maximum decrease in MAP during the infusion of KRN2391 at 1.0 and 5.0 μg·kg−1·min−1 was −13±7% (P<0.01) and −37±10% (P<0.01), respectively. The maximum reduction in SVR after 1.0 and 5.0 μg·kg−1·min−1 was −20±11% (P<0.01) and −60±16% (P<0.01), respectively. A KRN2391 infusion of 1.0 and 5.0 μg·kg−1·min−1 increased Cl a maximum of 11±13% (P<0.05) and 65±33% (P<0.01), respectively. KRN2391 1.0 μg·kg−1·min−1 showed a tendency to increase SVI but this change was not significant, KRN2391 5.0 μg·kg−1·min−1, however, produced a significant increase in SVI. The present results demonstrate that the decrease in MAP and the increases
in CI and SVI caused by KRN2391 are due to a reduction in the afterload. Therefore, we conclude that these cardiovascular
profiles of KRN2391 may be benificial in perioperative uses including the control of systemic blood pressure and the treatment
of hypertension during halothane anesthesia in clinical practice. 相似文献
12.
Tamikuni Komatsu Masayuki Nomura Youzou Kakudate Syuzou Fujiwara R. B. Heimann 《Macromolecular chemistry and physics.》1995,196(9):3031-3040
Dehydrochlorinated poly(vinylidene chloride) proved to be a conjugated polyene-polyene polymer. Shock compression of the polymer formed a large portion of graphite and trace amounts of diamond and of an unknown carbon. The unknown carbon belongs to the hexagonal crystal system and possesses the cell dimension α0 = 0.338 nm. A comparison with known carbynes was made in terms of the crystalline parameters. 相似文献
13.
M. Nakamura Michitaka Ozaki Shohei Fuchinoue Satoshi Teraoka Kazuo Ota 《Transplant international》1997,10(2):89-95
Ischemia-reperfusion injury by free radicals and lipid peroxides is observed in various organs. Ascorbic acid (AsA) or glutathione
(GSH) in various doses (AsA:2, 0.5, 0.1 mmol/kg, GSH:2 mmol/kg) was intraperitoneally administered to male Wistar rats. The
entire small intestines were resected just before ischemia, after ischemia, and after 20 min of reperfusion (n = 7–10 at each time point). At each time point, the specimens were subjected to assays of lipid peroxides, GSH, and glutaminase
activity of the tissues; they were also examined histologically. In the AsA group, the production of lipid peroxides after
reperfusion was significantly suppressed in a dose-dependent manner, and the ratio of oxidized GSH to total GSH was also significantly
low. Tissue glutaminase activity decreased to a lesser extent, and the degree of injury was apparently less marked in the
AsA group. This study indicates that AsA acts as an antioxidant against peroxidative tissue injury, possibly by scavenging
radicals, preserving reduced GSH, and reducing the peroxidative reaction.
Received: 21 June 1996 Received after revision: 8 October 1996 Accepted: 12 November 1996 相似文献
14.
15.
A Ueda K Aoyama T Ueda K Obama T Ueno S Hokama S Nomura 《British journal of industrial medicine》1992,49(7):499-506
The only workers presently exposed to bagasse dust in Japan are the employees of sugar refineries and lacquerware factories. A follow up study of six former cases of bagassosis from among the retired employees of a paper board factory, closed since 1973, showed that none of the subjects still had bagassosis. Examinations of 70 employees of a sugar refinery for allergic reactions also showed no case of bagassosis. Seven cases with suspicious shadows of bagassosis on chest radiographs and four cases with positive serum precipitin to stored bagasse were, however, found among those 70 subjects. The results show the disappearance of a past episode of bagassosis and the possibility of a new occurrence of bagassosis among the employees of sugar refineries and lacquerware factories in the near future in Japan. 相似文献
16.
Radiotherapy for pediatric brain stem glioma: radiation dose, response, and survival. 总被引:2,自引:0,他引:2
T Hibi N Shitara S Genka T Fuchinoue I Hayakawa T Tsuchida K Nomura T Kondo K Takakura 《Neurosurgery》1992,31(4):643-50; discussion 650-1
An analysis of 39 patients under 20 years of age with brain stem glioma treated with radiotherapy between 1977 and 1991 was undertaken. Twenty-eight (71.2%) of the patients responded well to initial radiotherapy, and 11 (28.8%) responded poorly. Median survival for the total patient population was 10 months. Response rates and median survivals were influenced by radiation dose: 45.5% and 9 months at doses less than 4499 cGy (n = 11), 83.3% and 13 months at doses between 4500 and 5499 cGy (n = 12), 66.7% and 11.5 months at doses between 5500 and 6499 cGy (n = 9), and 100% and 10 months at doses more than 6500 cGy (n = 7). Multivariate analysis revealed the response to initial radiotherapy was the only predictor of survival with radiation doses up to 6499 cGy. Four of the patients who responded well demonstrated radiological and/or histological calcification within or around the tumor at the time of clinical deterioration. Radiation injury was confirmed in two autopsy cases. The possibility that intratumoral radiation injury causes clinical deterioration is suggested. 相似文献
17.
A 41-year-old hemodialyzed woman developed ascites and was found to have secondary iron overload. The dose of administered iron was approximately 11-12 g, and her serum ferritin level was 15,000 ng/ml (15,000 micrograms/l). There were no signs of congestive heart failure, fluid overload, or liver cirrhosis. A program of weekly phlebotomy combined with recombinant human erythropoietin (rhEPO) therapy was tried to eliminate the iron congestion. After 9 months of this therapy, about 5 g of iron had been removed. The ascites completely disappeared, and her serum ferritin level fell to 5,800 ng/ml (5,800 micrograms/l). This suggests that such combined therapy would be useful when iron overload must be corrected rapidly. Before therapy, the sterile ascitic fluid showed exudative characteristics with 3.7 g/dl (37 g/l) of total protein. The serum-ascites albumin difference was 0.6 g/dl (6 g/l), and the fluid contained 1,400 inflammatory cells/mm3 (1.4 X 10(9)/l). Notably, the serum-ascites albumin difference increased in parallel with iron elimination. These findings suggested that iron deposition may have played a role in changing the permeability of the peritoneum, or in impairing lymphatic drainage, both of which are presumed to be pathogenetic factors of nephrogenic ascites. 相似文献
18.
19.
The association of replacement estrogens with breast cancer 总被引:4,自引:0,他引:4
A M Nomura L N Kolonel T Hirohata J Lee 《International journal of cancer. Journal international du cancer》1986,37(1):49-53
This epidemiologic case-control study examined the relationship between replacement estrogen use and breast cancer risk in 2 population groups in Hawaii. No significant associations were observed when 161 Caucasian cases were compared with either their neighborhood controls (RR = 0.9; 95% Cl = 0.5-1.3) or their hospital controls (RR = 0.7; 95% Cl = 0.4 to 1.1) and when 183 Japanese cases were compared with either their neighborhood controls (RR = 1.1; 95% Cl = 0.7-1.6) or their hospital controls (RR = 1.0; 95% Cl = 0.6-1.4). The results indicate that the use of replacement estrogens cannot account for the large difference in breast cancer incidence between the 2 Hawaiian ethnic groups. However, further data analysis involving neighborhood controls was suggestive of a possible increase in breast cancer risk with estrogen use for certain sub-groups of women who are at high risk for the disease. These included estrogen users with a family history of breast cancer or a history of benign breast disease. These findings are in agreement with other studies which have used non-hospitalized controls. Because the numbers of cases in this study are not substantial, it is recommended that a large population-based case-control study be undertaken to clarify the relationship between breast cancer risk and replacement estrogen use, especially in sub-groups of women at high risk for the disease. 相似文献
20.
Dotlike Hemosiderin Spots Are Associated With Past Hemorrhagic Strokes in Patients With Lacunar Infarcts 总被引:1,自引:0,他引:1
Toshio Imaizumi MD PhD Toshimi Honma MD PhD Yoshifumi Horita MD Satoshi Iihoshi MD PhD Tatsufumi Nomura MD Kazuhisa Yoshifuji MD Jun Niwa MD PhD 《Journal of neuroimaging》2005,15(2):157-163
BACKGROUND AND PURPOSE: Dotlike hemosiderin spots ongradient-echo T2(*)-weighted magnetic resonance imaging of the brain have been histologically diagnosed as old microbleeds associated with small vessel disease (SVD). The authors hypothesize that the presence of many dotHSs may be correlated with the fragility of small vessels and the recurrence of SVD, including lacunar infarction and deep intracerebral hemorrhage (ICH). METHODS: To investigate how dotHSs are related to past history of SVD, the number of subcortical or deep dotHSs was investigated in 146 patients with lacunar infarctions (95 men, 51 women, age 38 to 90 [66.6+/-9.4] years). They were divided into 2 subgroups according to history of deep ICHs or lacunar infarctions. The odds ratio (OR) for past history was estimated from logistic regression analyses with the number of subcortical or deep dotHSs as well as other factors. RESULTS: Of 146 patients with lacunar infarctions, 11 had past symptomatic ICHs and 19 had past symptomatic lacunar infarctions. An elevated rate of history of ICH was found for lacunar infarction patients with many deep dotHSs (>or=3; OR, 9.1; 95% confidence interval, 1.6-51, P=.015). However, history of lacunar infarction was not significantly associated with the number of subcortical or deep dotHSs. CONCLUSIONS: Our findings suggest that many deep dotHSs on T2(*)-weighted magnetic resonance imaging may be correlated with deep ICH-lacunar infarction type of SVD recurrence but not lacunar infarction-lacunar infarction type. 相似文献