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31.
Blocking effect of 1389-S on the sodium current in isolated guinea-pig ventricular myocytes 总被引:2,自引:0,他引:2
I Hisatome S Matsuoka J Miyamoto M Sawaguchi H Omodani S Osaki H Kotake H Mashiba R Sato 《European journal of pharmacology》1990,179(3):447-451
Under whole cell patch conditions, 1389-S blocked the INa in guinea-pig ventricular myocytes under steady state conditions (Kdrest = 30 microM, Kdi = 2.4 microM) with a shift of the inactivation curve to the hyperpolarizing direction. Both brief and long conditioning pulses could produce a use-dependent block of 1389-S. These results suggest that 1389-S had a higher affinity to the inactivated than to the rested state under steady state conditions and had a higher affinity to the activated state during train pulses as well as to the inactivated state, making channels unavailable for conduction upon activation. 相似文献
32.
Kazushi Kishi Taizo Takeuchi Tetsuo Sonomura Masashi Kimura Keisuke Kita Morio Sato Masaki Terada 《Cardiovascular and interventional radiology》1997,20(1):63-66
In order to treat fistulated esophageal cancer using a flexible stent, a covered flexible stent was constructed by wrapping
a nitinol stent with a thin sheet of Gore-Tex, preserving the stents original advantages of flexibility and a low-profile
introducer system. This stent was used to perform standard radiotherapy in a case of fistulated esophageal cancer. 相似文献
33.
34.
K Sugino Y Kure R Shiraishi H Iwasaki H Sato Y Kumamoto A Matsumoto 《Nihon Geka Gakkai zasshi》1990,91(8):923-930
Recently, mean span of life has been prolonged, and extensive operations are performed on aged patients. However, there are cases which have a difference between their chronological and actual ages. Bone mineral content (BMC) decreases with age and the decrease in BMC might suggest deterioration of immunological competence as observed in osteoporosis. Whether BMC can be an index for evaluation of geriatric patients' actual age from the aspect of immunological competence was investigated. Subjects were 54 cases aged more than 60. Twenty-one healthy young males and females were enrolled as the control group. Quantitative CT is used for assessment of BMC. The value obtained by dividing BMC by the standard BMC of the same age and sex, was defined as BMC index. BMC indices of normal BMC group were more than 0.8 and those of decreased BMC group were less than 0.8. Some immunological markers were investigated. Lymphocyte subset OKT3+ was reduced and juvenile lymphocytes expressed by OKT6+ and OKT3+-(OKT4+ + OKT8+) increased (corrected). Increased in juvenile lymphocyte and decrease in lymphocyte blast transformation and competence of generating interleukin 2 were observed in decreased BMC group. BMC is useful as preoperative evaluation for geriatric operative cases and patients of BMC index below 0.8 need to be paid attention to postoperative infection. 相似文献
35.
The effect of external gamma-irradiation on the digestive function of rat alveolar macrophages (AM) was studied by using the in vitro assay system, where the 59Fe release from AM engulfing 59Fe-iron hydroxide colloid was measured as an indicator of their digestive capability. Graded doses of gamma-irradiation up to 100 Gy had no effect on the extracellular release of 59Fe in AM cultured at 4 and 37 degrees C for 8-72 hrs postirradiation. When 10 mM Ca-DTPA was added to the culture medium, the 59Fe release was slightly depressed by irradiation at a dose of 30 Gy. It is apparent from these results that gamma-irradiation had no effect on the 59Fe transfer between cell and medium, and little effect on the catabolism of 59Fe-colloid in rat AM. 相似文献
36.
N. Inotsume M. Nishimura M. Nakano S. Fujiyama K. Sagara T. Sato K. Matsushita Y. Imai H. Matsui 《European journal of clinical pharmacology》1990,38(3):313-314
Summary The effect of haemodialysis on the pharmacokinetics of oral famotidine has been studied in five elderly anuric patients. Famotidine 20 mg was administered in a cross-over design to patients on and not on haemodialysis.The elimination rate constant of haemodialysis (k) was 4.6-fold larger than the systemic elimination rate constant (ke). Although the mean maximum serum concentration of famotidine during haemodialysis (141.5 ng·ml–1) was not significantly lower than that without haemodialysis (195.6 ng·ml–1), the AUC up to 5 h during haemodialysis was significantly decreased to 58.1% of the value without it.The data suggest that famotidine is dialysable by haemodialysis. 相似文献
37.
Spontaneous photon emission (chemiluminescence, CL) as a monitor of free radical evolution in Drosophila melanogaster which had been maintained at 25 or 30 degrees C for 5 days after emergence was measured. When maintained at 30 degrees C the fly CL intensity was stronger than at 25 degrees C. Under the condition of the higher temperature, the fly life span was shorter (mean life span = 29 days at 30 degrees C and 63 days at 25 degrees C), and oxygen consumption (3.7 microliters/mg.h at 25 degrees C, 4.9 microliters/mg.h at 30 degrees C) and the mobility (movement distance = 25 mm/min at 25 degrees C, 700 mm/min at 30 degrees C) increased, together with augmentation of phospholipid hydroperoxide in the fly total lipids. The CL spontaneously emitted from fly homogenate was decreased by the free radical scavengers both in experiments in vivo and in vitro. The hypothesis is proposed that as the oxygen metabolism grows active, the chemiluminescent reactions that involve oxygen-dependent free radical metabolism, including membrane phospholipid hydroperoxidation, contribute to the acceleration of senescence of fly bodies. 相似文献
38.
Because of the lack of adequate strength and toughness, hydroxyapatite (HA) ceramic can not be used for a substitute for a bone and joint despite its excellent affinity for the bone. The present authors have succeeded in producing a new type of HA ceramic containing zirconia. This new ceramic material is superior to ordinary HA ceramic in quality and exceeds compact bone in bending strength and fracture toughness. The Young's modulus was about 3-4 times greater than that of compact bone. The new ceramic material contained either 1.6 or 50% of zirconia by volume and was produced using a special technique to disperse the metal dioxide. In order to assess their affinity for the bone, the new ceramic materials were implanted into rabbit femurs. Sections of the bones removed at different times after operation were prepared without decalcification and subjected to optical microscopy, scanning electronmicroscopy (SEM), and electron-probe X-ray microanalyser (EPMA). The formation of direct chemical bonds with the bone was seen without intervening membrane. Thus, the new ceramic material was shown to have an excellent affinity for the bone, comparable to that of ordinary HA ceramic. 相似文献
39.
40.
HTLV-I seroprevalence in patients with malignancy 总被引:5,自引:0,他引:5
N Asou T Kumagai S Uekihara M Ishii M Sato K Sakai H Nishimura K Yamaguchi K Takatsuki 《Cancer》1986,58(4):903-907
Since many malignancies often occur in patients with smoldering type adult T-cell leukemia (ATL) (5 of 18 cases in this report), the relationship between HTLV-I (human T-cell leukemia virus type I) infection, which is closely associated with ATL, with other malignancies in an HTLV-I endemic area was examined. Among the 394 patients with malignancies and who had not had blood cell transfusions, 61 (15.5%) tested positive for HTLV-I antibody. The prevalence was significantly higher in males older than age 40 years and females of all ages compared to age- and sex-matched healthy individuals. The overall seroprevalence (26.1%) in 291 patients with malignancies and who had had blood cell transfusions was higher than that of those who had not had blood transfusions. There was no significant correlation between the site of malignancy and antibody prevalence. These results suggest the possibility that development of malignancy may contribute to expression of latent HTLV-I infection and that HTLV-I infection may contribute to the risk of other malignancies. 相似文献