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961.
962.
B Larsen B L Fox M F Burke V J Hruby 《International journal of peptide and protein research》1979,13(1):12-21
Experimental conditions and parameters involved in high performance liquid chromatography (HPLC) separations of the peptide hormone oxytocin and seven of its diastereoisomers, namely [1-hemi-D-cystine]-, [2-D-tyrosine]-, [4-D-glutamine]-, [5-D-asparagine]-, [6-hemi-D-cystine-], [7-D-proline]-, and [8-D-leucine]-oxytocin, on reverse phase columns were investigated. The effects of solvent, pH, and salt concentration were studied. Using the solvent systems 10% tetrahydrofuran-ammonium acetate buffer or 18% acetonitrile-ammonium acetate buffer and the muBondapak C18 support, oxytocin was separated from each of its diastereoisomers under all conditions studied, but the order of elution of diastereoisomers was highly dependent on solvent and to a lesser extent on pH. Separations of the hormone and its diastereoisomers on reverse phase HPLC and on classical partition chromatography on Sephadex G-25 were compared. The results are discussed in terms of the interactions of the solute with the reverse phase column and the solvent system. Implications of these findings in terms of the different solution conformations of the peptides are discussed. 相似文献
963.
Development of the electromotor system in Torpedo marmorata: Cationic staining of the electric organ
Geoffrey Q. Fox 《Cell and tissue research》1987,250(1):115-123
Summary The electric organs of embryonic Torpedo marmorala have been reacted with three cationic stains to evaluate the appearance and distribution of anionic sites. Ruthenium red, alcian blue and lysozyme were used at different pHs and found to react in a time-related manner to anionic components within the interelectrocyte space. The basal lamina covering the ventral electrocyte surface possesses the greatest number of anionic sites whereas growth cone, presynaptic terminal and glial membranes displayed almost no staining. Since this lamina serves as the exclusive substrate for ingrowing neuntes during synaptogenesis, the results are consistent with the idea that charge distribution on the membrane surface may provide a necessary cue for neurite motility, extension and eventual synaptogenesis. 相似文献
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965.
H. Fox 《BMJ (Clinical research ed.)》1997,314(7091):1363-1364
966.
Basophilic leukocytes in the hyperlipemic rabbit 总被引:1,自引:0,他引:1
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