Norikazu Shigeto

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The effect of the molecular weight of polymer powders and the polymer powder/liquid ratio on the viscoelastic properties after gelation of tissue conditioners was studied by means of a stress relaxation test. The results are summarized as follows. The lower-molecular-weight polymer powders produced the larger flow after gelation especially at long times.(More)
The integrin alpha9 subunit forms a single heterodimer, alpha9 beta1 that mediates cell adhesion to a site within the third fibronectin type III repeat of tenascin-C (TNfn3). In contrast to at least 3 other integrins that bind to this region of tenascin-C, alpha9 beta1 does not recognize the common integrin recognition motif, Arg-Gly-Asp (RGD). In this(More)
The rapid inward sodium current in spherical clusters of 11-d-old embryonic chick heart cells, ranging in size between 65 and 90 micron diameter, was studied using the two-microelectrode voltage-clamp technique. Using these preparations, it was possible to resolve the activation phase of the rapid inward current for potentials negative to -25 mV at 37(More)
Reactivation of the fast sodium current in spherical clusters of embryonic chick heart cells was studied using the two-microelectrode voltage-clamp technique. The results show that there are at least two phases of reactivation. The contribution of the two phases to the overall reactivation process is highly dependent on the particular pulse protocol used to(More)
The resting potential of various parts of the AV nodal regions of an excised rabbit heart was changed by applying constant electrical current with a suction electrode. The membrane potential was recorded with an intracellular microelectrode and the maximum rate of rise of depolarization was computed. The action potential recorded from the AV nodal cell(More)
Whether a given dose of ouabain will produce inotropic or toxic effects depends on factors that affect the apparent affinity (K0.5) of the Na/K pump for ouabain. To accurately resolve these factors, especially the effect of intracellular Na concentration (Nai), we have applied three complementary techniques for measuring the K0.5 for ouabain in cultured(More)
Intracellular acidosis is capable of stimulating a rapid amiloride-sensitive Na/H exchange mechanism in the cell membrane of cultured chick heart cells. The sequence of changes of intracellular sodium and potassium contents during recovery from an acid load in heart cells was determined by atomic absorption spectrophotometry and correlated with(More)
The effects of the molecular weight of polymer powders, the ethyl alcohol content of the liquids, the type of plasticizer and the polymer powder/liquid ratio on viscoelastic properties during gelation of tissue conditioners were studied with an oscillating rheometer. The results showed that: (i) The gelation time decreased exponentially with increases in(More)