[en] Contributions of rapid filling, slow filling and atrial systole to the left ventricular(LV) filling volume were analyzed with the use of radionuclide ventriculography at rest, both globally and regionally, in 34 patients with isolated disease of the left anterior descending coronary artery. The patients included 17 with a normal ejection fraction (EF≥50%; group 1) and 17 with a depressed EF (<50%; group 2), and the data were compared with those obtained from 13 normal subjects. A computer program subdivided the LV image into 4 regions, and time-activity curves were constructed globally and regionally by reverse-gating from the R wave. In both groups the contribution of rapid filling to the LV filling volume was decreased significantly in the affected septal and apical regions, and in the global left ventricle compared with that in normal subjects. In group 1, the contribution of atrial systole showed an increase in these affected regions and in the global left ventricle. In contrast, in group 2, the atrial contribution was not increased globally or regionally as much as was expected. However, the contribution of slow filling was either increased significantly or tended to increase in the affected regions and in the global left ventricle. There were negative correlations between the contribution of rapid filling and that of slow filling in the global left ventricle (r=-0.73, p<0.001) and in each of the septal, apical and lateral regions (r≥-0.60, p<0.001), which suggested that the contribution of slow filling as well as of atrial systole undergoes an increase as rapid filling is impaired. Thus, in patients with coronary artery disease, the left ventricle relies on slow filling as well as atrial systole to affect diastolic LV filling in the affected regions and in the global left ventricle in the presence of LV systolic dysfunction. (author)

[en] Soft error reduction by high-energy ion-implanted layers has been investigated by novel evaluation techniques using high-energy proton microprobes. A retrograde well formed by 160 and 700 keV boron ion implantation could completely suppress soft errors induced by the proton microprobes at 400 keV. The proton-induced current revealed the charge collection efficiency for the retrograde well structure. The collected charge for the retrograde well in the soft-error mapping was proved to be lower than the critical charge of the measured DRAMs(dynamic random-access memories). Complementary use of soft-error mapping and ion-induced-current measurement could clarify well structures immune against soft errors. (author)

[en] Injury and influence in the skin given by A-bomb are reviewed from the dermatological aspect. As an acute injury, primary and secondary thermal burns, flash and flame, respectively, are generally caused by high-energy heat. More than 90% people present within 1 km diameter area of the hypocenter died in a week and about 30% of whom did due to burns. Alopecia appeared in those who had been exposed to A-bomb radiation within 2.5 km diameter region of the hypocenter in Hiroshima and Nagasaki, and purpura, an important measure of radiation injury, occurred maximally 20-30 days after explosion in most of those people above. Late injury involves keloid and malignant skin tumor. The former, hypertrophic scar, was seen mainly in the curing process of the burns in 60-80% and was of somewhat different morphology after flash and flame injuries. In 1987, the correlation between the incidence of skin cancer and exposed dose was recognized in 20,348 survivors in Nagasaki. In the period from 1958 to 1987, the incidence of basal cell carcinoma was found increased in the comparative studies of about 90,000 people consisting of survivors and non-exposed control. Skin examination is pointed out from the aspect to be important in those people exposed to the higher radiation dose than general population, like workers in the nuclear power plant and medical field as well as in those enrolled in a nuclear accident. (R.T.)