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101.
Antti Keränen 《Chemistry and physics of lipids》1976,17(1):14-21
The fatty acid and long-chain base composition of five major gangliosides from human stomach and small and large intestine mucosa were analyzed with gas chromatography. All the gangliosides greatly resembled each other in the fatty acid pattern. The main fatty acids were C16:0, C18:0 and C24:0. No hydroxy fatty acids could be detected. In all the gangliosides 4-sphingenine was the predominant long-chain base (70–75%). About 15% of the long-chain bases had 20 carbon atoms in their chain. No trihydroxy long-chain bases could be detected. 相似文献
102.
A.I. Käiväräinen R.S. Nezlin 《Biochemical and biophysical research communications》1976,68(1):270-276
It is found that EPR spectra of immunoglobulins and their subunits spin-labeled by iminoxyl radical 2,2,6,6-tetramethyl-4-amino (N-dichlorotriazine) at pH 7.5 are similar in form and reflect the capability of spin-label to be in two states. Formation of specific complexes of spin-labeled antibodies with antigens is accompanied by increased correlation time of labels as well as by increased fraction of the labels in a more immobilized state. It is shown that splitting spin-labeled light chains to halves results in the label losing its capacity of being in the more rigid microenvironment. EPR spectra are interpreted as due to the relative motion of domains. 相似文献
103.
Summary The charge-pulse technique has been used previously for the study of quasistationary processes in membranes which required only a moderate time resolution. It is shown here that a time resolution of about 400 nsec may be achieved with this technique and that it may be applied to the kinetic analysis of carrier-mediated ion transport. By this method we have studied the transport of alkali ions through optically black monoolein membranes in the presence of the ion carrier valinomycin. All three relaxation processes that are predicted by theory have been resolved. From the relaxation times and the relaxation amplitudes the rate constants for the association (k
R
) and the dissociation (k
D
) of the ioncarrier complex, as well as the translocation rate constants of the complex (k
MS
) and the free carrier (k
S
) could be obtained. For 1m Rb+ at 25° C the values arek
R
=3×105
m
–1 sec–1,k
D
=2×105 sec–1,k
MS
=3×105 sec–1,k
S
=4×104 sec–1. The activation energies of the single rate constants which have been estimated from experiments at two different temperatures range between 50 and 90 kJ/mol. 相似文献
104.
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109.
Ohne ZusammenfassungMit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献