Dynamical Coherent-Potential Approximation (CPA) to correlated electrons has been extended to a system with realistic Hamiltonian which consists of the first-principles tight-binding Linear Muffintin Orbital (LMTO) bands and intraatomic Coulomb interactions. Thermodynamic potential and self-consistent equations for Green function are obtained on the basis of the functional integral method and the harmonic approximation which neglects the mode-mode couplings between the dynamical potentials with different frequency. Numerical calculations have been performed for Fe and Ni within the 2nd-order dynamical corrections to the static approximation. The band narrowing of the quasiparticle states and the 6 eV satellite are obtained for Ni at finite temperatures. The theory leads to the Curie-Weiss law for both Fe and Ni. Calculated effective Bohr magneton numbers are 3.0 µB for Fe and 1.2 µB for Ni, explaining the experimental data. But calculated Curie temperatures are 2020 K for Fe and 1260 K for Ni, being still overestimated by a factor of two as compared with the experimental ones. Dynamical effects on electronic and magnetic properties are discussed by comparing with those in the static approximations.

A new wavefunction which improves the Gutzwiller-type local ansatz method has been pro- Furthermore, the present approach combined with the projection operator method CPA is shown to describe quantitatively the excitation spectra in the insulator regime as well as the critical Coulomb interactions for a gap formation in infinite dimensions.

Marked differences have been reported in the prevalence of glutamic acid decarboxylase (GAD) antibodies between Caucasian (63–84 %) and Japanese (30–50 %) or Asian (5–50 %) IDDM patients. Using a new immunoprecipitation assay based on 125 l‐labelled recombinant human GAD65 , we have reassessed prevalence of GAD65 antibodies in Japanese patients. We also assessed prevalence of IA‐2 antibodies. GAD65 antibodies were detected in 83.3 % of sera taken within 1 year of onset, comparable to the prevalence reported in Caucasian patients. Positivity decreased to 66.7 % after 2 to 3 years and to 54.3 % after 3 years from onset, still higher than previously reported Asian prevalence. Except in one patient, high antibody levels persisted chronically, up to 12 years. There was no difference in the prevalence of GAD65 antibodies between Japanese IDDM patients with and without autoimmune thyroid disease (AITD). IA‐2 antibodies were detected in 64.7 % of sera taken within 1 year of onset. Prevalence of IA‐2 antibodies was lower than that of GAD65 antibodies. The difference in positivity in Asian IDDM patients between present and previous reports arose from the sensitivity of our assay for GAD65 antibodies. Additionally, the patients we studied had classic IDDM with a well‐defined onset. We conclude that prevalence of GAD65 antibodies in Japanese IDDM patients is comparable to that in Western studies. There was no relationship of GAD65 antibody positivity to coexistence of AITD. Our results suggest that autoimmunity is the most significant cause of Japanese IDDM. © 1997 by John Wiley & Sons, Ltd.

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