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111.
The effect of 6059-S, a novel 1-oxacephem, on peptidoglycan synthesis was investigated using ether-treated cells of Escherichia coli K 12, Pseudomonas aeruginosa KM 338 and Serratia marcescens IFO 12648. The cross-linking reaction of peptidoglycan synthesis in these organisms was inhibited by markedly low concentration of 6059-S.Non-standard abbreviations PBP
penicillin binding protein
- MIC
minimum inhibitory concentration
- ETB
ether treated bacterial cells
- SDS
sodium dodecylsulfate 相似文献
112.
113.
K Watanabe H Takeuchi 《Comptes rendus des séances de la Société de biologie et de ses filiales》1977,171(3):703-709
GABA, three of its derivatives (l-GABOB, d-GABOB and delta-amino valeric acid), acetycholine (Ach), dopamine (DA) and l-Phe-Tyr all inhibit an identifiable giant neurone (the TAN, tonically autoactive neurone) of Achatina fulica. These effects were examined by microdrop application in two different conditions: in physiological solution and in the absence of chloride ions. The results show that the relatively transient (rapid) inhibitions caused by GABA, by its derivatives and by Ach are dependent on chloride ions; the relatively maintained (long-lasting) inhibitions, caused by DA and l-Phe-Tyr, are independent of chloride ions. 相似文献
114.
Shuhichi Takahashi Susumu Kitanaka Michio Takido Ushino Sankawa Shoji Shibata 《Phytochemistry》1977,16(7):999-1002
From seedlings of Cassia torosa four dimeric hydroanthracenes have been isolated. Two, a pair of atropisomeric dimers consisting of two molecules o 相似文献
115.
Two patterns were found in the shifts of absorption peaks inspectra of intact etiolated Pharbitis cotyledons illuminatedat room temperature. One was a well-known pattern, P649C678C683C672,called the "high-intensity illumination pattern" in this study.The other, called the "low-intensity illumination pattern,"was P649C672. (Received June 16, 1976; ) 相似文献
116.
Lipid peroxide (LPO) formation was remarkable when isolatedtobacco chloroplasts were bubbled with high concentrations ofozone, though the fatty acid composition and the fractionationpattern of glycolipids and phospholipids in the chloroplastlipids changed little after ozone fumigation of the leaves.Piperonyl butoxide (PB), a potent protectant against ozone injury,strongly inhibited LPO formation in ozonated chloroplasts. PBalso prevented ozone-induced decreases in the amounts of linolenicand linoleic acids in the chloroplast lipids. These resultssuggest that PB inhibition of LPO formation may be involvedin the protective mechanism against ozone phytotoxicity. However,the mode of PB action differed on some points from that of diphenylamine,which is an antioxidant and also effective against ozone injury.The mode of PB action is discussed.
1 Present address: The Central Research Institute, Japan Tobacco& Salt Public Corporation, Umegaoka, Midori-ku, Yokohama227, Japan. (Received July 5, 1976; ) 相似文献
117.
The effects of various kinds of nitrogen compounds on the proliferation patterns ofAnkistrodesmus gracilis were examined. Among the tested compounds, the addition of peptone, arginine or glutamine to the N-free medium was the most effective on cell growth. The effectiveness was also shown in media containing one of several kinds of amino acid. In both peptone and arginine media the alga proliferated with multiple fission type of cell division, whereas the cultures grown in glutamine or serine medium contained 2-celled colonies at high frequencies. The latter was an efficient culture condition for cell reproduction with binary fission. The evidence for the behavior of nuclear and cytoplasmic division in these growth patterns were obtained from observations of thin sectioned materials. 相似文献
118.
Several strains of mice are known to develop spontaneous autoimmune diseases like lupus erythematosus and they show various immunological abnormalities as well. Despite different genetic backgrounds, they manifest various immunological abnormalities in common, e.g., polyclonal B-cell activation (PBA) and resistance to tolerance induction. To elucidate mechanisms of the development of autoimmunity, tolerance inducibility was examined in autoimmune and normal mice using trinitrophenylated carboxymethyl cellulose (TNP-CMC) as tolerogen which is known to induce TNP-specific B-cell tolerance without the participation of T cells. NZB and MRL/Mp-lpr/lpr mice were used as autoimmune mice and C57BL/6, BALB/c, and MRL/Mp-+/+ mice as nonautoimmune mice. When TNP-CMC-injected mice were challenged with T-independent antigens, all of the mice tested were shown to be tolerant. In contrast, when TNP-CMC-injected mice were challenged with T-dependent antigen and secondary IgG responses were assessed, autoimmune mice showed rather hyperreactivity, while nonautoimmune mice showed hyporesponsiveness. Cyclophosphamide improved this defective tolerance inducibility. By the solid-phase radioimmunoassay it was revealed that average affinity of serum anti-TNP antibodies produced in TNP-CMC-injected mice was low. Such low affinity antibodies were produced in large amount in autoimmune mice. Hence, it was suggested that B-cell clones destined to produce low affinity IgG antibodies were responsible for the resistance to tolerance induction and such clones were expanding in autoimmune mice. 相似文献
119.
Hepatocyte lysosomes, mitochondria, and peroxisomes show a dramatic translocation during mitosis induced by partial hepatectomy. During prophase, all three organelles move to the perinuclear cytoplasm. In metaphase, they become concentrated in the polar regions. During telophase, these organelles form clusters in the juxtanuclear regions. This organelle translocation is inhibited by the administration of a low concentration of colchicine, suggesting an involvement of microtubules in their movement. 相似文献
120.
Caprogammarus gurjanovae Kudrjaschov & Vassilenko, 1966 (Amphipoda: Caprellidea: Caprogammaridae) was redescribed based on the materials newly collected off Kushiro and Akkeshi, Hokkaido, Japan, which represents the southernmost record of this genus. Caprogammarus and Caprella share an identical feature, that of having the head and perionite I partially fused. Thus, Caprogammarus is considered to be a member of the suborder Caprellidea. 相似文献