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121.
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Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448
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C Guguen-Guillouzo J Marie D Cottreau N Pasdeloup A Kahn 《Biochemical and biophysical research communications》1980,93(2):528-534
Hepatocytes from a 4-month old fetus were cultured for 15 days. We found that fetal hepatocytes contained some R1 (precursor) form of L-type pyruvate kinase. Culture was associated with a considerable increase of the M2-type pyruvate kinase activity, but some L-type enzyme could be detected even after 10 days.Isozyme shift of phosphofructokinase seemed to be a progressive rather low phenomenon. Fetal hepatocytes showed an increase of the F-type form and a disappearance of the M-type form during culture. However, by day 10, the L-type enzyme remained predominant; this is in striking contrast with the findings reported on cultured fibroblasts.From these results, pyruvate kinase can be considered as a “strong” marker of cell differentiation, while phosphofructokinase is rather a “weak” marker. 相似文献
127.
Purine transport by Malpighian tubules of pteridine-deficient eye color mutants of Drosophila melanogaster 总被引:6,自引:0,他引:6
David T. Sullivan L. Anne Bell Duncan R. Paton Marie C. Sullivan 《Biochemical genetics》1979,17(5-6):565-573
Uptakes of guanine into Malpighian tubules of wild-type Drosophila and the eye color mutants white (w), brown (bw), and pink-peach (p
p) have been compared. Tubules for each of these mutants are unable to concentrate guanine intracellularly. The transport of xanthine and riboflavin is also deficient in w tubules. The transport of guanosine, adenine, hypoxanthine, and guanosine monophosphate is similar in wild-type and white Malpighian tubules. These data and other information about these mutants make it likely that these pteridine-deficient eye color mutants do not produce pigments because of the inability to transport a pteridine precursor. This view supports the hypothesis that mutants which lack both pteridine and ommochromes do so because precursors to both classes of pigments share a common transport system.This work was supported by Grant GM22366 from NIH. 相似文献
128.
Edward De Maeyer Marie -Christine Hoyez Jaqueline De Maeyer-Guignard Donald W. Bailey 《Immunogenetics》1979,8(1):257-263
Upon induction with Newcastle disease virus, peritoneal macrophages derived from C57BL/6 mice produced ten times as much interferon as macrophages derived from BALB/c mice. This suggested that the alleles of theIf-1 locus are expressed in vitro by these cells. Further evidence for this was obtained by studying interferon production by peritoneal macrophages derived from seven recombinant inbred and one congenic line: in each case there was complete correlation between in vivo and in vitro phenotype: macrophages fromIf-1l mice were low producers in vitro, and macrophages fromIf-1
h
mice were high producers in vitro. 相似文献
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James H. Allison Marie E. Blisner William H. Holland Paul P. Hipps William R. Sherman 《Biochemical and biophysical research communications》1976,71(2):664-670
Lithium was found to produce a marked elevation in the levels of -inositol 1-phosphate in the cerebral cortex of treated rats. This effect was completely inhibited by atropine. A 40% reduction in the levels of -inositol 1-phosphate was observed when atropine was given alone. 相似文献