Decoupling of the Dirac equation correct to the third order for the magnetic perturbation.

A two-component relativistic theory accurately decoupling the positive and negative states of the Dirac Hamiltonian that includes magnetic perturbations is derived. The derived theory eliminates all of the odd terms originating from the nuclear attraction potential V and the first-order odd terms originating from the magnetic vector potential A, which connect the positive states to the negative states. The electronic energy obtained by the decoupling is correct to the third order with respect to A due to the (2n+1) rule. The decoupling is exact for the magnetic shielding calculation. However, the calculation of the diamagnetic property requires both the positive and negative states of the unperturbed (A=0) Hamiltonian. The derived theory is applied to the relativistic calculation of nuclear magnetic shielding tensors of HX (X=F,Cl,Br,I) systems at the Hartree-Fock level. The results indicate that such a substantially exact decoupling calculation well reproduces the four-component Dirac-Hartree-Fock results.

Relativistic calculation of nuclear magnetic shielding tensor using the regular approximation to the normalized elimination of the small component. II. Consideration of perturbations in the metric operator.

A previous relativistic shielding calculation theory based on the regular approximation to the normalized elimination of the small component approach is improved by the inclusion of the magnetic interaction term contained in the metric operator. In order to consider effects of the metric perturbation, the self-consistent perturbation theory is used for the case of perturbation-dependent overlap integrals. The calculation results show that the second-order regular approximation results obtained for the isotropic shielding constants of halogen nuclei are well improved by the inclusion of the metric perturbation to reproduce the fully relativistic four-component Dirac-Hartree-Fock results. However, it is shown that the metric perturbation hardly or does not affect the anisotropy of the halogen shielding tensors and the proton magnetic shieldings.

Relativistic calculation of nuclear magnetic shielding tensor including two-electron spin-orbit interactions.

A relativistic calculation of nuclear magnetic shielding tensor including two-electron spin-orbit interactions is performed. In order to reduce the computational load in evaluating the two-electron relativistic integrals, the charge density is approximated by a linear combination of the squares of s-type spatial basis functions. Including the two-electron spin-orbit interaction effect is found to improve the calculation results.

Relativistic calculation of nuclear magnetic shielding using normalized elimination of the small component.

The normalized elimination of the small component (NESC) theory, recently proposed by Filatov and Cremer, is extended to include magnetic interactions and applied to the calculation of the nuclear magnetic shielding in HX (X=F, Cl, Br, I) systems. The NESC calculations are performed at the levels of the zeroth-order regular approximation (ZORA) and the second-order regular approximation (SORA). The calculations show that the NESC-ZORA results are very close to the NESC-SORA results, except for the shielding of the I nucleus. Both the NESC-ZORA and NESC-SORA calculations yield very similar results to the previously reported values obtained using the relativistic infinite-order two-component coupled Hartree-Fock method. The difference between NESC-ZORA and NESC-SORA results is significant for the shieldings of iodine.

[Concomitant operation of CABG and splenectomy following high-dose transvenous gamma-globulin therapy in a patient with idiopathic thrombocytopenic purpura--a case report].

A 60-year-old man with effort angina and idiopathic thrombocytopenic purpura (ITP) underwent concomitant operation of coronary artery bypass grafting (CABG) and splenectomy. High-dose transvenous gamma-globulin therapy (400 mg/kg/day) was performed for five days before surgery. The platelet count increased from 1.4 X 10(4)/mm3 to 8.7 X 10(4)/mm3. CABG was performed immediately followed by splenectomy. This is the first case with concomitant operation of cardiac surgery and splenectomy which was safely performed after high-dose transvenous gamma-globulin therapy.