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41.
Yoshiyasu Fukuyama Tsuneo Sato Iwao Miura Yoshinori Asakawa Tsunematsu Takemoto 《Phytochemistry》1983,22(2):549-552
From the methanol extract of the root of Polygonum hydropiper, a novel coumaryl glycoside hydropiperoside was isolated together with anthraquinone, ellagic acid 3,3′-di-O-methyl ether, gallic acid, two quercetin glycosides and an unidentified aromatic δ-lactone possessing antifertility activity. The structure of hydropiperoside was established as β-d-(1,3,6-tri-p-coumaryl)-fructofuranosyl-α-d-glucopyranoside by combination of extensive 1H NMR and 13C NMR spectra, and the FD/MS spectrum. 相似文献
42.
43.
Atsushi Imai Hiroaki Hattori Masaru Takahashi Yoshinori Nozawa 《Biochemical and biophysical research communications》1983,112(2):693-700
The regulation of human platelet responses by cyclic AMP (cAMP) has been investigated by measuring thrombin-stimulated serotonin release, Ca2+ uptake and phospholipase activity. Thrombin-induced 1,2-diacylglycerol (DG) formation as a result of phospholipase C activation was inhibited by pretreatment with dibutyryl cAMP (dbcAMP) in a dose-dependent manner. Subsequent failure to produce phosphatidic acid (PA), which is converted from 1,2-DG by phosphorylation and would serve as intracellular Ca2+ ionophore, appeared to parallel the decrease in Ca2+ uptake activity. Phospholipase A2 activity, monitored by the production of [3H]lysophosphatidylcholine and [3H]lysophosphatidylethanolamine, was also suppressed by dbcAMP. These data indicate that the intracellular cAMP level may be closely associated with Ca2+ uptake and phospholipases activation. In addition, it is suggested that alteration of intracellular cAMP regulates phospholipase activation and consequently platelet responses, perhaps by controlling available Ca2+ content. 相似文献
44.
An investigation was made on the factors influencing the acetic acid concentration in the culture liquid of the aerobic fermentations where acetie acid was used as a carbon source. The acetic acid concentration in the culture liquid changed in proportion to the amount of unutilizable acid or base supplied. This was explained by the principle of conservation of electroneutrality. Another factor affecting the acetic acid concentration in the culture liquid was bicarbonate ions which were formed by the dissolution and dissociation of carbon dioxide in the gas phase of the fermentor. The increment in bicarbonate ion concentration was equal to the decrement in the acetie acid concentration in the culture liquid. 相似文献
45.
46.
Hisashi Miyazaki Masatoshi Iida Yoshimasa Matsunaga Toshihiko Fujii Keiko Nambu Hideki Amejima Yoshinori Oh-e Hideo Furukawa Yukiharu Matsui Yasunobu Sohmura Masahisa Hashimoto 《Biotherapy》1989,1(1-2):47-57
The mode of antitumor action of rHu-TNF was elucidated in BALB/c mice bearing Meth A fibrosarcoma 7 days after transplantation with respect to time course, dose-response relationships and selectivity of the effects. The maximal cytotoxic effect on tumor cells revealed by inhibition of DNA synthesis and maximal lesional effect on tumor vasculature revealed by change in blood pool-size in the tissue were detected at 30 min and I h after administration of rHu-TNF, respectively. The dose-response relationship between cytotoxic and tumoricidal effects of rHu-TNF was irrespective of administration route. ED50s of these antitumor effects afteri.v. administration of rHu-TNF were about 50 times as high as ED50s afteri.t. administration. ED50 ofi.t. given rHu-TNF for vascular effect was about 20 times as high as that for cytotoxicity while ED50 ofi.v. rHu-TNF for vascular effect was only 2–3 times as high as that for cytotoxicity. The whole body autoradiographies with [125I] HSA giveni.v. to see the blood influx into tumor tissue and [14C]thymidine given i.v. to see DNA synthesis in the whole body after administration of rHu-TNF revealed that the distribution of radioactivity was markedly changed in the tumor alone without any detectable change in other whole body tissues.In conclusion, thein vivo antitumor effect of rHu-TNF giveni.t. ori.v., appears to be exerted through the direct action on Meth A sarcoma rather than indirectly on tumor vasculature. Under present conditions, the effect of rHu-TNF in the whole body tissues seems rather selective on cells and vasculature of the tumor. 相似文献
47.
A simple technique for reconstruction of the umbilicus, using a conchal cartilage composite graft 总被引:1,自引:0,他引:1
A simple technique to reconstruct the umbilicus is reported in which a conchal cartilage composite graft, such as that used in tragus construction in the treatment of microtia, was employed with a very satisfactory result. 相似文献
48.
Effects of the Histamine H3 -Agonist (R)-α-Methylhistamine and the Antagonist Thioperamide on Histamine Metabolism in the Mouse and Rat Brain 总被引:4,自引:4,他引:0
Ryozo Oishi Yoshinori Itoh Masahiro Nishibori Kiyomi Saeki 《Journal of neurochemistry》1989,52(5):1388-1392
To study the feedback control by histamine (HA) H3-receptors on the synthesis and release of HA at nerve endings in the brain, the effects of a potent and selective H3-agonist, (R)-alpha-methylhistamine, and an H3-antagonist, thioperamide, on the pargyline-induced accumulation of tele-methylhistamine (t-MH) in the brain of mice and rats were examined in vivo. (R)-alpha-Methylhistamine dihydrochloride (6.3 mg free base/kg, i.p.) and thioperamide (2 mg/kg, i.p.), respectively, significantly decreased and increased the steady-state t-MH level in the mouse brain, whereas these compounds produced no significant changes in the HA level. When administered to mice immediately after pargyline (65 mg/kg, i.p.), (R)-alpha-methylhistamine (3.2 mg/kg, i.p.) inhibited the pargyline-induced increase in the t-MH level almost completely during the first 2 h after treatment. Thioperamide (2 mg/kg, i.p.) enhanced the pargyline-induced t-MH accumulation by approximately 70% 1 and 2 h after treatment. Lower doses of (R)-alpha-methylhistamine (1.3 mg/kg) and thioperamide (1 mg/kg) induced significant changes in the pargyline-induced t-MH accumulation in the mouse brain. In the rat, (R)-alpha-methylhistamine (3.2 mg/kg, i.p.) and thioperamide (2 mg/kg, i.p.) also affected the pargyline-induced t-MH accumulation in eight brain regions and the effects were especially marked in the cerebral cortex and amygdala. These results indicate that these compounds have potent effects on HA turnover in vivo in the brain. 相似文献
49.
Katsuhiko Yokoi Mieko Kimura Yoshinori Itokawa 《Biological trace element research》1990,24(2-3):223-231
To clarify the influence of dietary tin deficiency on growth and mineral status, the following two different synthetic diets were fed to male Wistar rats: group 1—a diet containing 1.99 μg tin/g; group 2—a diet containing 17 ng tin/g. The rats in group 2 showed poor growth, lowered response to sound, and alopecia, with decreased food efficiency compared with rats in group 1. The changes of mineral concentrations in tissues observed in group 2, compared with group 1, are summarized as follows: calcium concentration in lung increased; magnesium concentration in lung decreased; iron concentrations in spleen and kidney increased; iron concentration in femoral muscle decreased; zinc concentration in heart decreased; copper concentrations in heart and tibia decreased; manganese concentrations in femoral muscle and tibia decreased. These results suggest that tin may be essential for rat growth. 相似文献
50.
Y. Hirose K. Ohmuro M. Saigoh T. Nakayama Y. Yamagata 《Origins of life and evolution of the biosphere》1990,20(6):471-481
A model primitive gas containing a mixture of N2, CO and water vapor over a water pool (300 mL, 37 °C) was subjected to electric discharges. The discharge vessel (7 L in volume) was equipped with a CO2 absorber (The CO2 being formed during the discharge), thus simulating possible absorption of CO2 in the primitive ocean. The vessel also has a cold trap ( –15 °C), which protects the primary products against the further decomposition in the discharge phase by enabling these products to adhere to the trap. Since the partial pressures of CO and N2 decreased at rates of 1.5–1.7 cmHg day–1 and 0.1–0.2 cmHg day–1, respectively, the gases were added at regular intervals. The solution was analyzed at regular intervals for HCN, HCHO and urea, and maximum concentrations of about 50, 2, and 140 mM were observed. The discharge phase was continued for 6 months. In the solution, glycine (5.6% yield based on the carbon), glycylglycine (0.64%), orotic acid (0.004%) and small amounts of the other amino acids were found. 相似文献