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        564.
        1992.12 KCI 등재 서비스 종료(열람 제한)
        Physiological toxic and mutagenic effects of gramoxone in Drosophila melanogaster were invetigated. Gramoxone was highly toxic on the development, resulting in of lowering the viability and in prolongation of the developmental times. Adults treated with gramoxone during the developmental stages caused a lowering of the productivity and a little change in protein quantity. But the effect on the sex-linked lethal mutagenesis was found to be negative. The order of mortality causing adult stage feeding to gramoxone in the D. melanogaster complex was like this ; D. mauritiana, D. sechellia, D. simulans and D. melanogaster. Two species of the D. yakuba complex were alike. Those results were more or less correlation with speciation of the D. melanogaster subgroup.
        566.
        1992.07 KCI 등재 서비스 종료(열람 제한)
        The inhibitory effects of mercury ions on the growth of barley seedlings were studied and the distribution of metal elements in the organs of treated plants was investigated by using synchrotron radiation induced X-ray emission (SRIXE). Although the treatment of mercury ions caused growth inhibition, the mercury-specific increase in variable fluorescence and the abolishment of energy-dependent quenching in broken barley chloroplasts as shown by Moon et al. (1992) were not observed in the leaves of growth-inhibited seedlings. Instead the treatment of mercury decreased Fmax and Fo values. However, Fmax/Fo ratio and photochemical and nonphotochemical quenching coefficients were not affected significantly. By SRIXE analysis of 10μM mercury chloride treated seedlings, accumulation of mercury in roots was observed after 1 hour of treatment and similar concentration was sustained for 48 hours. Relative contents of mercury was high in roots and underground nodes where seeds were attached, but was very low in leaves. Iron and zinc were also distributed mainly in the lower parts of the seedlings. However after 72 hours of treatment the contents of these metals in roots decreased and their distribution became more uniform, which may lead to death of the plants. These results suggest that the observed inhibitory effects on barley seedlings upto 48 hours after the treatment is not due to direct damages in the photosynthetic apparatus, but due to its accumulation in roots and the consequent retardation of the growth of barley seedlings. The decrease in Fmax and Fo is probably due to the decrease in chlorophyll and protein contents caused by the retardation of growth. The observed slow expansion of primary leaves could be also explained by the retardation of growth, but the fluorescence induction pattern from the leaves did not show characteristic symptoms of leaves under water stress.
        567.
        1992.05 KCI 등재 서비스 종료(열람 제한)
        In the preliminary antitumor screening tests of Crude Drugs and collected plants, the methanol ic extract of Forsythia Fruits in Korean marcket showed signif icant cytotoxic activity against Chinese hamster V-79 cells, but that in Japanese market did not. The former was identifid as Forsythia viridissima Lindley and latter as F.suspensa Vahl on the basis of the morphological observation. When an aqueous solution of the extract prepared from the fruits of F. viridissima (Oleaceae) was partitioned successively with n-hexane, methylene chloride, n-butanol, the cytoyoxic activitywas concetrated in the methylene chloride extract. Fractionation of the extract was made with the guidance of bioassay against V-79 cells to give cytotoxic lignans, matariresiol (1) and arctigenin (2). Their ICso values of compounds 1 and 2 were respectively 7.8 μg/ml 1 and 1.65 μg/ml. Also, their structures were confirmed by comparison of physical and spectral data in the literature.
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