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51.
52.
Yukio Yamagata Atsunori Yamashita Katsuhiko Inomata 《Origins of life and evolution of the biosphere》1980,10(1):47-50
Di-and tri-glycine were synthesized in 1M aqueous solution of glycine by bubbling for 90 hr with oxygen discharged in the path from an oxygen cylinder. The peptides were also produced by an incubation at 37°C of 2M glycine solution prepared with 75% hydrogen peroxide, and the yields were traced for 200 days. The final yields were about 0.25% and 0.01% for di-and tri-glycine, respectively. The solution at 166 days of incubation was applied to a Sephadex G 10 column, and the fractions around the top of the chromatogram were found to increase the intensity of ninhydrin color about 45 times after hydrolysis, indicating an existence of oligo-glycine. The solutions of 1M glycine and 0.5M diglycine prepared with 30% hydrogen peroxide were incubated at 37°C for 38 days, and di-and tetra-glycine were detected in the yields of 0.12% and 0.33%, respectively. 相似文献
53.
Kozo Yamamoto Tetsuya Tosa Kiyokazu Yamashita Ichiro Chibata 《Biotechnology and bioengineering》1977,19(8):1101-1114
The kinetics of the reversible fumarase reaction of immobilized Brevibacterium ammoniagenes cells and the decay behavior of enzyme activity were investigated in a plug flow system. The time course of the reaction in the immobilized cell column was well explained by the time-conversion equation including the apparent kinetic constants of the immobilized cell enzyme. The decay rate of fumarase activity was faster in the upper sections of the column (inlet side of the substrate solution) compared with the lower sections when 1M sodium fumarate (pH 7.0) was continuously passed through the column at 37°C. It was shown that the decay rate of the fumarase activity in the immobilized cell column depends on the flow rate of the substrate solution. The effect of flow rate on the decay rate of enzyme activity was considered to be related to the rate of contamination of enzyme with poisonous substances derived from the substrate solution or to the rate of leakage of enzyme stabilizers and/or enzyme itself from the immobilized cells. 相似文献
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Yoshiteru Harada Kunio Tanaka Kowa Yamashita Masataka Ishibashi Hiroshi Miyazaki Makoto Katori 《Prostaglandins & other lipid mediators》1983,26(1):79-90
Intrapleural injection of 2% λ-carrageenin caused the accumulation of exudate up to 19 hr. The rate of plasma exudation, measured by the exuded dye amounts for 20 min in the pleural cavity after intravenous injection of pontamine sky blue, showed a peak at 5 hr. Aspirin (100 mg/kg, i. p.) suppressed the dye exudation up to 5 hr, but did not at 7 hr. This inhibition coincided with the decrease of the PG and TXB2 levels, which were measured by gas chromatography-mass spectrometry, in the pleural exudate. In vitro experiments, MK-447, a phenolic compound, stimulates PG endoperoxide biosynthesis at lower doses and inhibits it at higher doses, acting as a tryptophan-like cofactor required by PG endoperoxide synthetase. This drug (0.3, 1.0 and 3.0 mg/kg, i. p.) suppressed the dye exudation dose-dependently up to 5 hr, but did not at 7 hr even at a higher dose, in combination with the dose-dependent decrease of the pleural level of PGE2, which was reported to be a major PG among PGs and TXB2 in the exudate in inducing the plasma exudation (Harada
; Prostaglandins,
: 881, 1982). Thus, the anti-inflammatory action of MK-447 can be explained by inhibition of PGE2 generation, giving no consideration to the role of oxygen-derived free radicals as a prime mediator in inflammation. 相似文献
56.
K Kawai A Fukamizu Y Kawakami M Matsumura K Mitsui K Murakami K Yamashita 《Endocrinologia japonica》1991,38(6):603-609
A 54-year-old woman was referred to our hospital for the treatment of a tumor of the right chest wall. Clinical examination revealed hypertension, hypokalemia, metabolic alkalosis, hyperaldosteronism and hyperreninemia. Computed tomography and an abdominal echogram indicated a tumor in the right phrenic area and two tumors in the retroperitoneum near the pancreas head. After the surgical resection of these tumors, the primary reninism was diminished. The pathological diagnosis of these tumors was leiomyosarcoma. Plasma active and inactive (trypsin-activated) renin activities (PRA) were 85.7 and 38.9 ng angiotensin I/ml/h, respectively. These PRA did not respond to either postural stimulation or suppression by the volume expansion. Active and inactive renin activities in a right phrenic area tumor were 208 and 32 ng angiotensin I/mg protein /h, respectively. Those of an abdominal tumor were 196 and 30 ng angiotensin I/mg protein/h, respectively. Renin mRNA identical in molecular size to that of the human kidney was identified by northern blot analysis. This is the first case report of renin producing leiomyosarcoma derived from the lung, which is characterized by relatively lower plasma prorenin concentrations. 相似文献
57.
S Yamadera K Yamashita N Kato M Akatsuka K Miyamura S Yamazaki 《Japanese journal of medical science & biology》1991,44(1):29-39
In Japan, herpangina cases increase every summer with an incidence peak in July. During the past eight years from January, 1982 to December, 1989, a total of 3,974 viruses from herpangina cases were reported from 47 participating laboratories, and coxsackie A (CA) viruses accounted for most of them, 3,055 (76.9%). The major types associated with herpangina were, in order of frequency, CA4, 10, 5, 6, 2 and 3, representing 87.2%-80.8% of total isolations reported for each respective type in this period. Eighty-four point four percent of the total virus isolations were from children at four years of age or younger. More than 80% of total CA virus isolations were from nasopharyngeal specimens and nearly 90% of the viruses were isolated in mice. 相似文献
58.
K Miyamura K Yamashita S Yamadera N Kato M Akatsuka M Hara S Inouye S Yamazaki 《Japanese journal of medical science & biology》1992,45(4):203-214
This report presents an overall distribution of poliovirus isolations in Japan, where poliomyelitis has been under control over two decades as a result of legal administration of two doses of the trivalent live oral poliovirus vaccine of the Sabin strains (OPV) to children under 48 months of age. During the past 12 years from 1980 through 1991, a total of 1,126 poliovirus isolations from humans and 268 isolations from sewage/river water were reported by respectively 49 and nine of the participating laboratories. Type 2 was most frequently isolated from children after administration of one dose of OPV, followed by type 1 and type 3. On the contrary, after the second dose of OPV, the rate of isolation of type 3 exceeded those of type 2 and type 1. Seasonal and age distribution of poliovirus isolations from both humans and sewage/river water paralleled the OPV vaccination schedule in Japan. One percent of the isolations were, however, from infants younger than the vaccination-scheduled ages and 5% were from children older than those ages, including one each from 15 and 16 years olds. The data indicate that the poliovirus has silently been disseminated from vaccinated children to others and the community, thus suggesting repeated transmission of the viruses. The fact that some elder children had poliovirus colonization in their alimentary tracts indicates a potential risk of infection of such a population when exposed to a wild virus and of becoming a source of transmission to others. 相似文献
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