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51.
α-Methylene-γ-aminobutyric acid was isolated and characterized from fruit bodies of Mycena pura. It was the decarboxylation product of l-γ-methyleneglutamic acid by l-glutamic acid decarboxylase. 相似文献
52.
cis-5-Hydroxy-L-pipecolic acid was isolated and characterized from the leaves of Morus alba and the seeds of Lathyrus japonicus. The trans-form was also obtained from the former. 相似文献
53.
M Kuwabara K Tanabe W Hiraoka Y Tamura F Sato A Matsuda T Ueda 《Chemico-biological interactions》1991,79(3):349-358
The exposure of log-phase Chinese hamster V79 cells to 2-chlorodeoxyadenosine (CdA) for 3 h after X irradiation enhanced the lethal effects of X-rays in a concentration-dependent manner. The enhancement of the killing efficiency of X-rays by CdA was mainly observed in the reduction of quasi-threshold doses (Dq) of the dose-response curves. When the ability of CdA to inhibit the repair of X-ray-induced double- and single-strand breaks (dsb and ssb) of DNA was investigated by neutral- and alkaline-filter elution techniques, respectively, it was observed that 90% of dsb were rejoined in the absence of CdA within 30 min after X irradiation and 15-40% of dsb rejoining was suppressed by co-incubation of the cells with 5-10 microM of CdA for 3 h after X irradiation, whereas almost 100% of ssb were rejoined within 15 min regardless of the presence or absence of CdA. From these results it was concluded that CdA interfered exclusively with the repair of DNA dsb in X-irradiated Chinese hamster V79 cells and thereby increased the lethality of X-rays. 相似文献
54.
An annual average of 163 Kuril seals was found dead in two years in salmon trap nets along the coastal waters of the Nemuro Peninsula and adjacent areas. The seal-caused damage to the total salmon catch at the salmon trap nets was concentrated in some of them, particularly No. 27, where seals killed or injured 5.1% of the catch in 1982, and 1.8% in 1983. Based on the proportion of Kuril seals among the dead seals in the trap nets, it was estimated that Kuril seals damaged 4.7% of the total salmon catch at No. 27 in 1982, and 1.7% in 1983. Not all seals that entered the trap net drowned; some killed or damaged salmon, and then escaped. 相似文献
55.
H. Toh C. Yokoyama T. Tanabe T. Yoshimoto S. Yamamoto 《Prostaglandins & other lipid mediators》1992,44(4)
Four oxygenases of the arachidonic acid cascade (cyclooxygenase, 5-lipoxygenase, 12-lipoxygenase and 15-lipoxygenase) were investigated by the method of computer-assisted sequence comparison. From the calculations, some aspects of evolution and function of these enzymes were revealed. (1) The evolutionary origin of cyclooxygenases was different from that of lipoxygenases. (2) Cyclooxygenase was a distantly related member of a peroxidase family. (3) Enzymes with 12-lipoxygenase activity were created independently twice by gene duplication. 相似文献
56.
57.
T Yoshimoto Y Yamamoto T Arakawa H Suzuki S Yamamoto C Yokoyama T Tanabe H Toh 《Biochemical and biophysical research communications》1990,172(3):1230-1235
The cDNA for a 12-lipoxygenase was isolated from cDNA library of human erythroleukemia cells. The cDNA had an open reading frame encoding 663 amino acids with a calculated molecular weight of 75,513. The deduced amino acid sequence of human 12-lipoxygenase exhibited 41.5%, 65.3% and 65.4% identity with human 5-lipoxygenase, human 15-lipoxygenase and porcine 12-lipoxygenase, respectively. Blot hybridization analysis of RNA from human erythroleukemia cells demonstrated a single species (3.1 kb) of mRNA with the cDNA probe for 12-lipoxygenase of these cells, but not with the cDNA for porcine leukocyte enzyme. The cytosol of Escherichia coli transformed with a recombinant pUC19 plasmid oxygenated the position 12 of arachidonic acid. 相似文献
58.
Carbohydrate fermentation by Clostridium difficile 总被引:1,自引:0,他引:1
Biochemical properties of Clostridium difficile were reinvestigated for the practical identification of the organism in clinical laboratories. Bacterial growth in 2% proteose peptone medium supplemented with 0.01% L-cysteine.HCl and 0.1% agar supported sufficient growth to read the fermentation results just as well as did pre-reduced anaerobically sterilized medium. Incubation for 2 days was long enough for determining the ability to ferment fructose, glucose, mannitol, mannose, melezitose, and sorbitol. All of the 82 strains liquefied 2% but not 10% gelatin. The significance of mannitol fermentation and gelatin liquefaction is stressed since C. difficile is the only species fermenting mannitol among the gelatin-liquefying species of clostridia having subterminal spores. 相似文献
59.
Ken Nozawa Takayoshi Shotake Yoshi Kawamoto Yuichi Tanabe 《Primates; journal of primatology》1982,23(3):432-443
Amount of genetic differentiation between chimpanzee and man was estimated from the result of comparative electrophoretic
screening of blood protein variations at 32 independent genetic loci. TheNei's genetic distance (D) was calculated as 0.4514, and from this value the divergence time between the two species was estimated as 2.26 million
years; considering the variation among amino-acid substitution rate in different proteins, the corrected figures were given
as genetic distance of 0.5706 and divergence time of 2.85 million years. This genetic difference is considered too small the
two species to be allocated in different families, in accordance with the results of the similar kind of analyses byKing andWilson (1975) and Bruce andAyala (1979). Discussions were made for a discrepancy between the divergence times estimated by using and not by using the splitting
time recognized by paleoprimatologists as a reference, and for the difference in the estimations made in different laboratories. 相似文献
60.
Population genetics of Japanese monkeys: II. Blood protein polymorphisms and population structure 总被引:4,自引:4,他引:0
Ken Nozawa Takayoshi Shotake Yoshi Kawamoto Yuichi Tanabe 《Primates; journal of primatology》1982,23(2):252-271
Genetic variability in individual troops of the Japanese macaque (Macaca fuscata fuscata) was quantified by the proportion of polymorphic loci and the average heterozygosity per individual from the results of starch-gel
electrophoreses of blood proteins controlled by 32 independent genetic loci. The former averaged 9.2% and the latter 1.3%,
the values being remarkably lower than those estimated for other animal populations. Geographical distribution of the genetic
variations was not uniform in the whole species but the variants occurred only in limited areas. Assuming the selective neutrality
of segregating alleles and the two-dimensional stepping-stone model of population structure, the genetic migration rate between
the local demes per generation could be estimated to average less than inverse of average effective deme size. Here, the local
deme is not a troop itself, but it consists of several troops tightly connected with each other by frequent exchanges of reproductive
males. Analyses of correlation between geographic and genetic distances between troops revealed that the gene constitutions
of two troops apart more than 100 km on an island could be regarded as practically independent of each other. These results
suggest that the population structure of the Japanese macaque species has a tendency to split into a number of local subpopulations
in which the effect of random genetic drift is prevailing. 相似文献