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61.
Toxic effects on the retina by oral administration of thioridazine was investigated by electroretinography (ERG) using male Wistar rats. An obvious reduction followed by a disappearance in the O2 component of the oscillatory potentials of the ERG was seen in a dose-dependent manner. The minimum dosage given to produce the above change was 3 mg/kg/day for 7 days' administration. This change seemed to be permanent, whereas a and b waves as well as other oscillatory potentials, e.g., O1, O3, were normal throughout the experiment. The significance of the data is discussed.  相似文献   
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With the expanding elderly population in Japan, general anesthesia in patients above 80 years of age has become routine and is increasing. We report on a case of general anesthesia for a 100-year-old woman with chronic heart failure. This patient could not decide on anything about her own treatment plan because of dementia, and the operation was undertaken from strong request of her family. There was no cardiopulmonary instability during the operation, but heart failure became worse postoperatively, and it took nearly a month before the patient could leave the hospital. As for the operation and general anesthesia in the elderly, it is important not only to assess their perioperative physical risks but also to consider family background and postoperative course.  相似文献   
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Recent neuroimaging studies support the view that a left-lateralized brain network is crucial for language development in children. However, no previous studies have demonstrated a clear link between lateralized brain functional network and language performance in preschool children. Magnetoencephalography (MEG) is a noninvasive brain imaging technique and is a practical neuroimaging method for use in young children. MEG produces a reference-free signal, and is therefore an ideal tool to compute coherence between two distant cortical rhythms. In the present study, using a custom child-sized MEG system, we investigated brain networks while 78 right-handed preschool human children (32-64 months; 96% were 3-4 years old) listened to stories with moving images. The results indicated that left dominance of parietotemporal coherence in theta band activity (6-8 Hz) was specifically correlated with higher performance of language-related tasks, whereas this laterality was not correlated with nonverbal cognitive performance, chronological age, or head circumference. Power analyses did not reveal any specific frequencies that contributed to higher language performance. Our results suggest that it is not the left dominance in theta oscillation per se, but the left-dominant phase-locked connectivity via theta oscillation that contributes to the development of language ability in young children.  相似文献   
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In a normal man sitting upright, pulmonary perfusion is several times greater in the lower lung zone than in the upper zone. This pattern may sometimes be reversed in patients with cardiac disease. Tc99m-macro-aggregated albumin pulmonary perfusion images were computerized to isocounts area images (digital perfusion images; DPI). DPI were applied to various types of cardiac disease and patterns of DPI were divided into 4 classes according to amount of nonperfused pulmonary vascular bed. C-0; normal perfusion. C-1; decrease of nonperfused pulmonary vascular bed. C-2; disappearance of nonperfused pulmonary vascular bed. C-3; decrease of pulmonary vascular bed. In 71 patients with mitral stenosis relationships between pulmonary hemodynamics during exercise and distribution of pulmonary perfusion were studied, i.e. at rest (n = 71, mean pulmonary arterial pressure; 23 mmHg-cardiac index; 2.4 L/m) and during exercise C-0 (n = 13, 41 mmHg-5.4 L/m), C-1 (n = 17, 52 mmHg-5.2 L/m), C-2 (n = 27, 52 mmHg-4.5 L/m) and C-3 (n = 14, 65 mmHg-3.6 L/m) respectively. In patients with congestive heart failure cardiac status was classified to 4 classes according to ejection fraction and DPI. Patients with EF less than 30% and DPI more than C-2 showed high morbidity and mortality (two years mortality 47%; 27/40). Pulmonary venous pressure increases to maintain the cardiac index (Starling's law) in cases of decline in cardiac function or mitral stenosis. It was shown that increases in pulmonary venous pressure cause changes in distribution of pulmonary perfusion, which in turn works to depress the cardiac index. A decline in cardiac function and changes in the distribution of pulmonary perfusion coexist, mediated by pulmonary venous pressure and cardiac index. The distribution of pulmonary perfusion reflects the severity of cardiac failure itself, so by using DPI the severity of cardiac failure can be easily evaluated.  相似文献   
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