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41.
Hitoshi Sato Yuichi Sugiyama Yasufumi Sawada Tatsuji Iga Manabu Hanano 《Life sciences》1984,35(10):1051-1059
A rapid radioreceptor assay for measuring ß-endorphin (ß-EP) in unextracted serum has been developed. The method is based upon the inhibition by ß-EP of 3H-naloxone binding to the specific receptors on rat brain membranes, prepared in a stable form of pellets. Effect of serum on the assay was minimized by adding pooled serum to the equal dilution of total serum in the assay mixture. Pharmacokinetic analysis of pharmacologically active ß-EP equivalents (ß-EP eq.) in rats was performed using this method. The serum disappearance of ß-EP eq. after iv administration followed a biexponential decline and pharmacokinetic parameters were calculated by a two-compartment open model. The half-lives of α-phase and ß-phase were 2.6 ± 0.5 min and 6.2 ± 1.6 hr (mean ± SE; n=6), respectively. The volume of the central compartment (V1) and that of steady-state (Vdss) were 67 ± 16 and 480 ± 75 ml/kg (mean ± SE; n=6), respectively. The total body serum clearance (CLtot) was 2.1 ± 0.9 ml/min/kg (mean ± SE; n=6). The serum disappearance curve of ß-EP eq. obtained in the present study was similar to that previously reported by Houghten et al. (Proc. Natl. Acad. Sci. U.S.A. , 4588–4591 (1980)), in which the disapperance of total radioactivity of tritiated ß-EP in rats was examined. 相似文献
42.
Takashi Tsuchiya Atsushi Ichimura Yoshinori Nagai 《Cell biochemistry and biophysics》1987,11(1):109-122
Correlations in the baker map and the tent map as examples of one-dimensional, fully developed chaos are considered. It is
shown, utilizing symbolic dynamical systems derived from these maps, that the vanishing second-order correlation function
is not sufficient to guarantee uncorrelatedness. Importance of the higher-order, especially third-order, correlation functions
is emphasized for chaotic systems. In search of the quantities that grasp correlational behaviors as a whole in chaotic systems,
it is proposed to use the fixed-separation correlation integral, which is a modified quantity of the usual correlation integral
devised to calculate the fractal dimension of strange attractors, for these maps. It is shown that the new quantity contains
all the even-number orders of autocorrelation function that are commonly considered. 相似文献
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49.
Makoto Suematsu Shigenari Houzawa Soichiro Miura Hiroshi Nagata Tetsuji Kitahora Tetsuo Morishita Chikara Oshio Masaharu Tsuchiya 《Luminescence》1989,4(1):531-534
Reaction difference of oxyradical generation and luminol-dependent photoemission of zymosan- and phorbol ester-treated neutrophils were investigated using a conventional photomultiplier and ultrasensitive photonic imaging technique. Zymosan-treated cells released a concentrated photonic burst corresponding to the cellular distribution. In contrast, phorbol ester-treated cells produced a negligible level of photoemission, and the additional application of Ca2+ ionophore enhanced the photonic burst, which was gradually spread out into extracellular space. Serine protease inhibitors did not attenuate PMA-induced chemiluminescence but did attenuate zymosan-induced chemiluminescence. This suggests the involvement of serine protease in the respiratory burst of phagocytizing neutrophils. 相似文献
50.
H Sakurai M Nakai T Miki K Tsuchiya J Takada R Matsushita 《Biochemical and biophysical research communications》1992,189(2):1090-1095
Vanadyl ion (+4 oxidation state) has been shown to be an effective agent for chemoprotection of cancers in animals. For understanding the mechanism, distribution of vanadium was studied. More vanadium was found to accumulate in the nuclei of the liver of rats when it was given as vanadyl sulfate than when it was given as sodium vanadate (+5 oxidation state). The reactivity of vanadyl ion with DNA was investigated by the DNA cleavage technique and the reaction mechanism by ESR spectroscopy. Incubation of double-strand DNA with vanadyl ion and hydrogen peroxide resulted in marked concentration- and pH-dependent DNA cleavage. Studies by the ESR spin-trap method demonstrated that hydroxyl radicals are generated during the reactions of vanadyl ion with hydrogen peroxide. Thus the antineoplastic action of vanadyl ion is proposed to be due to DNA cleavage by hydroxyl radicals generated in the cells. 相似文献