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91.
Multiple Molecular Forms of Acetylcholine Receptors in Cultured Skeletal Muscle Cells: Subcellular Localization and Characterization 总被引:1,自引:0,他引:1
Abstract: Skeletal muscle cells of newborn rats, cultured in the absence of neuronal influence, were found to contain two types of cell surface acetylcholine receptors as demonstrated by isoelectric focusing. The isoelectric points of the two types of receptors were indistinguishable from those of junctional and extrajunctional types of receptors in mature animals. The cultured cells had two classes of intracellular α-bungarotoxin (αBT) binding components; one had the same sedimentation coefficient as that of surface receptors (9S), and the other had much smaller apparent molecular weights. Only a single major component was detected by isoelectric focusing analysis of the 9s intracellular aBT binding component, with a PI value close to that of the extra junctional receptor. These results suggest that the junctional and extrajunctional types of receptors may be synthesized through a common precursor. 相似文献
92.
Two new non-protein amino acids, Nδ-benzoyl-l-ornithine and Nδ-benzoyl-l-γ-hydroxyornithine have been characterized from the seeds of Vicia pseudo-orobus. 相似文献
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Ayako Ueki Yukiko Fukushima Tetsuo Kimoto 《Virchows Archiv. B, Cell pathology including molecular pathology》1976,22(1):315-321
The presence of C3 receptor sites on the cell surfaces of WI-38 fibroblasts was reported in a previous paper. Here the effect of dexamethasone
sodium sulfate of C3 receptor site function was studied. The incubation of WI-38 fibroblasts with dexamethasone sodium sulfate produces the biphasic
mode of action, i.e., the growth-stimulating phase with low doses (90–230 μg/ml) and the growth-inhibiting phase with high
doses (450–900 μg/ml). The function of C3 receptor sites on WI-38 fibroblasts seems to be very stable and cannot be suppressed by the pretreatment of WI-38 fibroblasts
with dexamethasone in high concentrations, where the cell growth is inhibited. 相似文献
96.
A male infant with monosomy 21. 总被引:2,自引:0,他引:2
A male infant with total monosomy 21 identified by Q-, G- and R-banding is described. His main symptoms are hypertonia, micrognathia, microphthalmus, imperforate anus, ambiguous external genitalia, floating and malopposed thumbs, overlying fingers, right clubfoot and growth retardation. Both parents are phenotypically as well as karotypically normal. 相似文献
97.
Vibrio parahaemolyticus was observed to adsorb onto chitin particles and copepods. The efficiency of adsorption was found to be dependent on pH and on the concentration of NaC1 and other ions found in seawater. Highest efficiency was observed in water samples collected from Chesapeake Bay and lowest in water from the open sea. V. parahaemolyticus was found to adborb onto chitin with the highest efficiency of the several bacterial strains tested. Escherichia coli and Pseudomonas fluorescens did not adsorb onto chitin. The adsorption effect is considered to be one of the major factors determining the distribution of this species and affecting the annual cycle of V. parahaemolyticus in the estuarine system. 相似文献
98.
Y Kaneko 《Hormones et métabolisme》1976,8(3):202-206
Thyroid cells from euthyroid patients with Graves' disease were cultured in a chemically defined medium. The cells preserved the ability to respond to TSH with 8-fold increase in cyclic AMP concentration. This cyclic AMP response to TSH was diminished by prior exposure of cells to TSH. The decrease in cyclic AMP response to TSH induced to TSH was reversible, was not associated with a similar decrease to cyclic AMP response to PGE1, and could not be attributed to increased phosphodiesterase activity or to decreased adenyl cyclase activity. The partial resistence to TSH stimulation of thyroid cells previously exposed to TSH may be due to changes in the TSH receptor, possibly caused by TSH itself. 相似文献
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