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951.
952.
Studies on a new human cell line (SiHa) derived from carcinoma of uterus. I. Its establishment and morphology 总被引:12,自引:0,他引:12
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955.
ACTIVATION OF HEXOSE MONOPHOSPHATE PATHWAY IN BRAIN BY ELECTRICAL STIMULATION IN VITRO 总被引:2,自引:1,他引:1
Abstract— The incubation of cerebral cortical slices for 15 min in Krebs-Ringer-tris (pH 7.6) solution at 37°C with [1-14 C]glucose or [6-14 C]glucose as substrates yielded a C-1:C-6 14 CO2 ratio of 1.21, whereas this ratio increased to 3.01 after the application of electrical stimulation (ES). Tissue levels of 6-phosphoglu-conate (6PG) and glucose 6-phosphate (G6P), intermediary metabolites of hexose monophosphate (HMP) pathway, were 7 and 180 nmol/g tissue following 15 min incubation, and increased by 33 and 45 per cent respectively following the application of ES. Activities of 6-phosphogluconate dehydrogenase (6PGDH, 6-phospho- d -gluconate: NADP+ 2-oxidoreductase, EC 1.1.1.44) and glucose-6-phosphate dehydrogenase (G6PDH, d -glucose-6-phosphate: NADP+ 1-oxidoreductase, EC 1.1.1.49), important enzymes in regulating the activity of HMP pathway, in cerebral cortical slices were 689 and 907 pmol/mg protein/min and were increased by 66 and 25 per cent respectively by the application of ES. Synaptosomal G6PDH and 6PGDH activities were maximally activated by the addition of 40 m m -Na+ to the reaction mixture, whereas no activation by Na+ was observed in microsomal G6PDH and 6PGDH. Amobarbital inhibited more strongly the Embden–Meyerhof (EM) pathway than the HMP pathway, while imipramine had a stronger inhibitory effect on HMP pathway than on EM pathway in the electrically stimulated cerebral tissues.
The present results indicate that the HMP shunt pathway in the cerebral cortex is activated by the application of ES in vitro , possibly at synaptic regions and may play an important metabolic and functional role in the brain. 相似文献
The present results indicate that the HMP shunt pathway in the cerebral cortex is activated by the application of ES in vitro , possibly at synaptic regions and may play an important metabolic and functional role in the brain. 相似文献
956.
Erythromycin resistant mutants of Bacillus subtilis 总被引:6,自引:0,他引:6
K. Tanaka M. Tamaki S. Osawa A. Kimura R. Takata 《Molecular & general genetics : MGG》1973,127(2):157-161
Summary Erythromycin resistant (ery
r) mutants were isolated from Bacillus subtilis ATCC 6633. The composition of ribosomal proteins were analyzed for thirteen such ery
r-mutants with chromatography on a carboxymethyl cellulose (CMC) column. The 50s subunit from all of the ery
r-mutants was found to contain the altered 50d protein. The ribosomes prepared from the ery
r-mutants did not show in vitro alteration of the ability to combine with erythromycin. 相似文献
957.
Genetic and chemical studies of ribosomes from spectinomycin resistant mutants of Bacillus subtilis 总被引:2,自引:0,他引:2
Summary Spectinomycin resistant mutants were isolated fromBacillus subtilis ATCC 6633. Some of these mutants had an altered specific 30s ribosomal protein on CMC chromatography, the site of alteration residing in a different tryptic peptide fragment from one mutant to another on Dowex 50×8 chromatography.This work was supported by a grant from the Mitsubishi Foundation and grants from the Ministry of Education of Japan. 相似文献
958.
Masatoshi Kobayashi Masayoshi Yamazaki Shigeru Kimura 《Journal of insect physiology》1973,19(4):857-859
The rôle of the brain hormone as an activation hormone of the prothoracic glands in silkworm larvae was examined using decapitated larva of the fourth instar. The gland was activated by the brain hormone injected and induced early larval or larval-pupal apolysis. 相似文献
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960.