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81.
David C. Turner Rudolf Gmür Herbert G. Lebherz Marianne Siegrist Theo Wallimann Hans M. Eppenberger 《Developmental biology》1976,48(2):284-307
The presence or absence of five proteins (glycogen phosphorylase, aldolase A, aldolase C, creatine kinase M, creatine kinase B) in the various classes of cells found in primary cultures derived from embryonic chick breast muscle was investigated using cytological staining methods. Histochemical staining for phosphorylase and indirect fluorescent antibody staining for aldolase A and C as well as for creatine kinases M and B showed the following: All five proteins were found in the many myotubes present in standard medium cultures and in the very few myotubes found in cultures containing 5-bromodeoxyuridine (10?5M). The elongated bipolar cells prevented from fusing in medium containing EGTA also contain all five proteins. The flattened myogenic cells that predominate in the 5-bromodeoxyuridine-treated cultures contain no phosphorylase or creatine kinase M, though many of them contain creatine kinase B and aldolases A and C. These results are interpreted as indicating that: (1) phosphorylase and creatine kinase M, but not aldolase A, are suitable all-or-none markers for terminal muscle differentiation; (2) the small amounts of creatine kinase M detected in electrophoreses of 5-bromodeoxyruridine-treated cultures can be accounted for by the few myotubes present and are not due to “protodifferentiation” of large numbers of cells; (3) proteins typical of differentiated muscle are produced only in cells that have passed through the last step in myogenesis that is susceptible to 5-bromodeoxyuridine inhibition, and (4) if fusion is blocked by reducing the concentration of calcium ions, accumulation of characteristic muscle proteins can continue in those cells that have initiated terminal differentiation. 相似文献
82.
It was shown that the aglycone of the main saponin of Primula elatior (L.) Hill is not primulagenin A but protoprimulagenin A with an oxide ring between C-13 β and C-28 in the β amyrin ring system. 相似文献
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84.
Lemperg Rudolf K. Bergenholtz Axel Smith T. W. D. 《In vitro cellular & developmental biology. Plant》1975,11(5):286-290
In Vitro Cellular &; Developmental Biology - Plant - Articular cartilage from 6-month-old calves was maintained in organ culture in Eagle's minimum essential medium at different oxygen... 相似文献
85.
New observations are presented on the internal ultrastructure of the scale–bearing chrysophycean genera Chromophysomonas, Chrysosphaerella , the new genus Polylepidomonas and 15 species of Paraphysomonas. These data show that the pigmented genera Chromophysomonas, Chrysosphaerella and Polylepidomonas have a generally similar internal structure and that their taxonomic separation is based only on differences in scale structure. The structure of Paraphysomonas resembles that of these genera but the cells always possess a leucoplast rather than a chloroplast. In cell structure, the pigmented genera resemble the naked genus Ochromonas while Paraphysomonas resembles Spumella , the colourless counterpart of Ochromonas. Evaluation of the differences between these genera and the scale–bearing genera Mallomonas and Synura has led to the conclusion that Chromophysomonas, Chrysosphaerella, Polylepidomonas and Paraphysomonas should no longer be classified within the family Mallomonadaceae. The new family Paraphysomonadaceae is established to include Chrysophyceae with an Ochromonas type of cell structure but which also produce silica scales. 相似文献
86.
Rudolf Keller 《Protoplasma》1931,13(1):463-480
Zusammenfassung Aus unseren Versuchen, die durch konforme am Darm ergänzt werden 1), läßt sich schließen, daß bei der gerichteten Wanderung charakteristisch geladener Substanzen und des Wassers durch die tierische Haut die elektrische Kataphorese sicherlich beteiligt ist. 相似文献
87.
Dr. Rudolf Scharfetter 《Plant Systematics and Evolution》1912,62(4):109-114
Ohne Zusammenfassung 相似文献
88.
Ann-Kathrine Granerus Rudolf Jagenburg Stig R?djer Alvar Svanborg 《BMJ (Clinical research ed.)》1971,4(5782):262-264
Oral and intravenous L-phenylalanine loading tests were performed in 13 Parkinsonian patients and in 12 control subjects matched for age and weight. The results showed a normal intestinal absorption and a normal elimination from plasma of phenylalanine in the Parkinsonian patients. 相似文献
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