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排序方式: 共有582条查询结果,搜索用时 15 毫秒
121.
S Komatsu J Panés JM Russell DC Anderson VR Muzykantov M Miyasaka DN Granger 《Canadian Metallurgical Quarterly》1997,29(2):683-689
Recent reports indicate that bacterial endotoxin (lipopolysaccharide) and cytokines elicit a more profound increase in the surface expression of intercellular adhesion molecule-1 (ICAM-1) in cultured endothelial cells derived from spontaneously hypertensive (SHR) versus normotensive Wistar-Kyoto rats (WKY). Our objective in this study was to characterize and compare in vivo ICAM-1 expression in SHR and WKY under basal conditions and after 5 hours of endothelial cell activation with either lipopolysaccharide (5 mg/kg i.p.) or tumor necrosis factor-alpha (TNF-alpha; 1, 5, and 10 micrograms/kg i.p.). ICAM-1 expression was quantified in different tissues by the double-radiolabeled monoclonal antibody technique. When constitutive (baseline) ICAM-1 expression was corrected for endothelial cell surface area, significantly higher values were noted in SHR than WKY but only in splanchnic organs. Lipopolysaccharide and TNF-alpha elicited significant increases in ICAM-1 expression in all tissues of both WKY and SHR. However, the magnitude of the lipopolysaccharide-induced ICAM-1 upregulation in heart, stomach, skeletal muscle, and brain was significantly lower in SHR than WKY. A similar blunted ICAM-1 upregulation was noted in the stomach of SHR after administration of 5 micrograms/kg TNF-alpha. The differences in induced ICAM-1 expression between SHR and WKY do not appear to be due to differences in endothelial cell surface area or plasma glucocorticoid levels. These results suggest that chronic arterial hypertension results in altered ICAM-1 expression on the endothelium, which may contribute to the abnormal inflammatory responses associated with this disease. 相似文献
122.
This paper proposes a numerical computer method for formal linearization of nonlinear systems by using the discrete Fourier expansion. A nonlinear system is described by a system of nonlinear ordinary differential equations. A linearizing function is given by a sequence of trigonometric functions. The nonlinear terms of the differential equations are expanded into finite sums of trigonometric functions by the method of the discrete Fourier expansion. As a result, a formal linear system is derived from the given nonlinear system. A computer algorithm of the linearization is acquired and numerical computation is easily carried out with the aid of computers. Further, as the application of the linearization, both a nonlinear observer and a nonlinear filter are synthesized in this paper. Examples show that the accuracy of the method is improved as the order of the trigonometric functions increases. 相似文献
123.
M Tsukamoto H Kimura S Sumita Y Ujike M Kaneko S Komatsu 《Canadian Metallurgical Quarterly》1989,9(5):472-477
Five hundred and thirty-three patients have been treated after thoracic and cardiovascular surgery in our ICU during the last four years. Cardiac failure was shown in 150 cases, respiratory failure in 132 cases, renal failure in 76 cases, and hepatic failure in 84 cases. The appropriate mechanical organ-supports (MOS) were applied in the following cases: intra-aortic balloon pumping (IABP) in 48 cases, veno-arterial bypass (VAB) in 18 cases, left ventricular assist device (LVAD) in 1 case, respirator in 132 cases, continuous hemofiltration (CHF) in 44 cases, hemodialysis (HD) in 13 cases, peritoneal dialysis (PD) in 21 cases, Continuous intensive peritoneal dialysis (CIPD) in 7 cases, and plasma exchange (PEx) in 22 cases. The results of MOS6 which required exocorporeal circulation were not satisfactory, especially CHF (mortality rate 75.0%), HD (76.9%), and VAB (100%). Though, the results of IABP (35.4%) and CIPD (14.3%) were significantly better. The main cause of early death (within 6 post-operative days) was low output syndrome (LOS) (63.6%). However, that of late death (beyond 14 post-operative days) was sepsis (66.7%). Therefore, it is important for the survival of these patients to control LOS during the early post operative period and then to concentrate on the prevention of infection. 相似文献
124.
T. Sato Y. Tokunaga T. Endo M. Shimada K. Komeya K. Nishida M. Komatsu T. Kameda 《Journal of Materials Science》1988,23(10):3440-3446
The leaching behaviours of hot-pressed Si3N4 ceramics containing Y2O3, Al2O3 and AIN as additives and hot isostatically pressed Si3N4 without additives were studied in 0.1 to 10 M HF aqueous solutions at 50 to 80° C. Silicon and aluminium ions were dissolved into the HF solutions, but yttrium ion did not dissolve at all and formed insoluble YF3. The dissolution of silicon and aluminium ions was controlled by the surface chemical reaction and the apparent activation energies were 70.5 to 87.6 kJ mol–1, respectively. The corrosion rate increased with increasing degree of crystallization of the grain boundary phases. The corrosion resulted in roughness of the surface and degradation of the fracture strength. Si3N4 ceramics containing an amorphous phase at the grain boundaries showed the most excellent resistance to corrosion with HF solution, and kept a fracture strength of above 400 M Pa even after leaching 40% of the silicon ions. 相似文献
125.
126.
127.
To assess the degree of noise pollution in relation to the health and safety of the employees and commuters, a study on the levels of noise originating from various locomotives and also from different other sources was undertaken at Kalupur railway station of Gujarat State in India. The sound pressure levels (SPL) were measured on platforms. Noise dose count was monitored on a ticket collector on duty for 8 h. The results reflected that the SPLs in the platforms well exceeded the day time noise exposure limit. Further, the SPLs produced by loudspeakers were high and those by train whistles were intensely high pitched. The noise dose count of the ticket collector was also in excess of ACGIH standard. All these suggest that the SPLs in the platforms can endanger the healthful living of the users. Suitable control measures have been suggested. 相似文献
128.
The interdigital glands of a Japanese serow infected with parapoxvirus had severe papular and nodular lesions that completely occupied the sac and duct of the gland. The lesions were characterized by acanthosis with hyperkeratosis. Intracytoplasmic inclusion bodies were detected in the vacuolated prickle cells. By electron microscopy, mature and immature viral particles were present in the cytoplasm. These glands act as scent glands, and lesions in this organ probably affected the ecological adaptation of this individual. 相似文献
129.
M Yamamoto K Fukuda N Miura R Suzuki T Kido Y Komatsu 《Canadian Metallurgical Quarterly》1998,27(4):959-966
The authors previously reported that transforming growth factor beta1 (TGF-beta1) induces apoptosis in McA-RH7777 (7777) and McA-RH8994 (8994) rat hepatoma cell lines. Although these cell lines exhibit different responses to glucocorticoid treatment in various cellular functions and gene expression, dexamethasone (DEX) inhibited spontaneous and TGF-beta1-induced apoptosis in both. Analysis of analogous hormones in TGF-beta1-induced apoptosis in 8994 cells suggested the inhibitory effect to be glucocorticoid-specific. By cell-cycle analysis and DNA fragmentation assay using sodium butyrate, a G1-arrest-inducing reagent, regulation of apoptosis by TGF-beta1 and DEX was shown independent of the cell cycle. For elucidation of the mechanisms of anti-apoptotic action of DEX, the effects of various chemical probes on this apoptosis model were examined, and various reagents known to exhibit anti-apoptotic activity in other experimental systems were found to be ineffective. The effect of TGF-beta1 and DEX on cellular amounts of several apoptosis-related proteins, members of the Bcl-2 family, Bcl-2, Bcl-xL, Bcl-xS, Bad, and Bax was also examined. DEX drastically increased Bcl-xL in both cell lines irrespective of the presence of TGF-beta1. Bcl-2 and Bcl-xS proteins were not detected, and Bax and Bad content did not change by treatment with TGF-beta1 or DEX. Progesterone (Prog), a partial antagonist for glucocorticoid receptor, inhibited the effects of DEX on apoptosis and Bcl-xL expression in 8994 cells. Thus, Bcl-xL induction by DEX would appear closely associated with its inhibitory effect on spontaneous and TGF-beta1-induced apoptosis in the hepatoma cell lines. 相似文献
130.
AL Li Y Komatsu Y Ono F Nakatani K Nakashima N Yamaguchi 《Canadian Metallurgical Quarterly》1996,70(7):717-726
The acquired immunodeficiency of the host plays an essential role in the occurrence of infections even with low pathogenic bacteria. The increase of cases with MRSA and/or pseudomonas infection is one of the serious problems in hospital management in Japan for the elderly as well as pediatric patients. In the present study, mitomycin C (MMC)-treated hosts were prepared in young, adult and old mice to test the immunopotentiating action of the promising Chinese herbal medicine, Tohki-Rikuoh-Toh (TRT), Hotyu-Ekki-Toh (HET) and Juzen-Taiho-Toh (JTT). The effect of these herbal medicines on organ structure and its function in the MMC-treated hosts is clarified and discussed for medical use. 4-5, 8-10 and over 50 week old male C57BL/6 (Clea Japan Inc.) were injected with MMC at a dosage of 3 to 5 mg/kg to inhibit the bone marrow, thus creating a mouse model with reduced immunopotential. A powder extract of TRT, HET and JTT was administrated orally at a dosage of 500 mg/kg/day for seven consecutive days. The white cell number and the subset analysis were carried out by the FACS method. The bactericidal effect of the host was monitored by NBT reduction test. Peritoneal macrophages were prepared by the adherence technique. The macrophage phagocytic activity was examined by an ACAS system. After the administration of TRT, HET and JTT, the body weights recovered as much as 90%, especially in young animals which had been reduced to 75% of their normal values. After MMC-treatment, with the herbal medicines, HET was good for young mice while JTT was effective for the old ones. As for the effect on B cells, the plaque-forming cells (PFC) of spleen cells were compared among the groups. As a result, PFC in the HET group was 184% and the other two were 80 approximately 95% as compared to 76% in the MMC-treated ones. The number of white blood cells in the MMC-treated mice returned to 80% of their normal value. In addition, the phagocytic activity of macrophages increased to 50% although that of the non-treated group was only 20%. The phagocytic activity also recovered in the JTT and TRT of 131% to 95%, respectively compared to 11% in the MMC-treated control. When TRT, HET and JTT were administered orally to mouse models whose immunopotential had been inhibited, the herbal medicines activated both quantitatively and qualitatively, showing themselves to be effective interstitial medicines. In addition, the data from the animal models showed no side effects, confirming the complete efficacy of the drug. Moreover, there was no direct anti-bactericidal effect from these medicines, suggesting that the immunomodulating action of this medicine is host-mediated. It is interesting that quantitative and qualitative recovery were seen when HET was administered to MMC-treated young hosts while JTT was good for the old. With this investigation, the effective components are still unknown for different generations, and we need to clarify this aspect for better understanding of the efficacy of herbal medicines. 相似文献