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871.
S Nakamura J Hattori M Ishiyama-Takuno H Shima I Matsui S Sakata 《Endocrinologia japonica》1992,39(5):469-476
In this paper, we report a 49-year-old female with subacute thyroiditis who had thyroid-stimulating antibodies (TSAb) and thyroid-stimulation-blocking antibodies (TSBAb) in serum. Although she was in the thyrotoxic phase and TSH was suppressed in May, 1990, her radioactive iodine uptake (RAIU) was not suppressed (35.5%) and a thyroid scan disclosed a diffuse goiter with no defect. Serum assays revealed the presence of TSAb, but TSBAb were negative. In August, 1990, the right lobe became undetectable by thyroid scan when the RAIU was 20.7% with the TSH level remaining suppressed. At that time, TSAb were negative, while TSBAb were positive. When the RAIU was 31.1% in October, 1990, both thyroid lobes became visible and the TSH level was normalized. TSBAb became negative, and although TSAb reappeared it later became undetectable. These results indicate that the changes in the patient's thyroid scan and RAIU were attributable to the presence of TSAb. 相似文献
872.
T Fukushima T Homma K Harakawa N Sakata T Azuma 《Journal of biomechanical engineering》1988,110(3):166-171
Visualization experiments were performed to elucidate the complicated flow pattern in pulsatile flow through arterial bifurcations. Human common carotid arteries, which were made transparent, and glass-models simulating Y- and T-shaped bifurcations were used. Pulsatile flow with wave forms similar to those of arterial flow was generated with a piston pump, elastic tube, airchamber, and valves controlling the outflow resistance. Helically recirculating flow with a pattern similar to that of the horseshoe vortex produced around wall-based protuberances in circular tubes was observed in pulsatile flow through all the bifurcations used in the present study. This flow type, which we shall refer to as the horseshoe vortex, has also been demonstrated to occur at the human common carotid bifurcation in steady flow with Reynolds numbers above 100. Time-varying flows also produced the horseshoe vortex mostly during the decelerating phase. Fluid particles of dye solution approaching the bifurcation apex diverged, divided into two directions perpendicularly, and then showed helical motion representing the horseshoe vortex formation. While this helical flow was produced, the stagnation points appeared on the wall upstream of the apex. Their position was dependent upon the flow distribution ratio between the branches in the individual arteries. The region affected by the horseshoe vortex was smaller during pulsatile flow than during steady flow. Lowering the Reynolds number together with the Womersley number weakened the intensity of helical flow. A separation bubble, resulting from the divergence or wall roughness, was observed at the outer or inner wall of the branch vessels and made the flow more complicated. 相似文献
873.
874.
Akira Minematsu Yasue Nishii Susumu Sakata 《Journal of musculoskeletal & neuronal interactions》2021,21(2):287
Objective:This study aimed to explore optimal conditions of whole-body vibration (WBV) for improving bone properties in aged rats.Methods:Eighty-week-old rats were divided into baseline control (BC), age-matched control (CON) and experimental groups, which underwent WBV (0.5 g) at various frequencies (15, 30, 45, 60 or 90 Hz) or WBV (45 Hz) with various magnitudes (0.3, 0.5, 0.7 or 1.0 g) for 7 weeks. After interventions, femur bone size, bone mechanical strength and circulating bone formation/resorption markers were measured, and trabecular bone microstructure (TBMS) and cortical bone geometry (CBG) of femurs were analyzed by micro-CT.Results:Several TBMS parameters and trabecular bone mineral content were significantly lower in the 15 Hz WBV (0.5 g) group than in the CON group, suggesting damage to trabecular bone. On the other hand, although frequency/magnitude of WBV did not influence any CBG parameters, the 0.7 g and 1.0 g WBV (45 Hz) group showed an increase in tissue mineral density of cortical bone compared with the BC and CON groups, suggesting the possibility of improving cortical bone properties.Conclusion:Based on these findings, it should be noted that WBV conditions are carefully considered when applied to elderly people. 相似文献
875.
Eosinophil-directed chemotactic inhibitory factors (ECIF) from T lymphocytes of complete Freund's adjuvant-treated guinea pigs were recovered in two separate molecular weight (MW) fractions: the one is eluted near bovine serum albumin (MW about 70,000), and in pH range between 7.0 and 7.5 by chromatofocusing column, whereas the other is near cytochrome c (MW 12,500), and in pH range between 5.0 and 5.5. It was, however, found by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoadsorption that the high molecular ECIF is probably an aggregated form of the low molecular ECIF. It was subsequently confirmed that both the ECIF had similar physicochemical properties: sensitive to heating at 56 or 80 degrees C sensitive to enzyme treatment with trypsin and neuraminidase, sensitive in acid but not alkaline condition, and bind to peanut agglutinin-or Limulus polyphemus agglutinin-coupled agarose beads. The inhibitory activity of ECIF was suppressed by previous treatment of eosinophils with D-galactose and sialic acid. ECIF activity was specifically absorbed by eosinophils; the absorption was inhibited by pretreatment of eosinophils with D-galactose and sialic acid. Previous treatment of eosinophils with beta-galactosidase and neuraminidase led the cells not to respond to both ECIF. It was thus suggested that the inhibition by ECIF is receptor-mediating phenomenon, and that ECIF and ECIF receptors on eosinophils contain galactose and sialic acid residues which may play an essential role for the biological activity. 相似文献