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991.
K Shinozaki M Suzuki M Ikebuchi H Takaki Y Hara M Tsushima Y Harano 《Canadian Metallurgical Quarterly》1995,92(7):1749-1757
BACKGROUND: It is generally believed that coronary artery spasm plays an important role in the progression of obstructive coronary artery disease. Since insulin resistance together with hyperinsulinemia plays an important role in the pathogenesis of coronary atherosclerosis, we investigated the association of hyperinsulinemia and insulin resistance with vasospastic angina (VAP). METHODS AND RESULTS: The study population consisted of 60 patients with VAP and 42 control subjects (62 subjects with normal glucose tolerance and 40 with impaired glucose tolerance). Insulin sensitivity was determined by the steady-state plasma glucose (SSPG) method for nondiabetic, normotensive, nonobese subjects (16 control subjects, 16 obstructive coronary artery disease patients, and 16 VAP patients). Compared with the control group, the 2-hour insulin area (area under the plasma insulin concentration-time curve) during a 75-g oral glucose tolerance test was significantly higher in both VAP groups with normal and impaired glucose tolerance. A high frequency of vasospastic angina was observed in subjects with clustered risk factors for insulin resistance syndrome, suggesting a close association of VAP with this syndrome. In stepwise discriminant analysis, the 2-hour insulin area was significantly associated with VAP independent of other risk factors. SSPG level in VAP was about twofold over control, indicating the presence of insulin resistance in patients with VAP. However, no differences were found between patients with VAP and obstructive coronary artery disease with respect to mean SSPG level. CONCLUSIONS: SSPG level was significantly elevated in patients with VAP and obstructive coronary artery disease compared with control subjects. This indicates that hyperinsulinemia is secondary to insulin resistance, both of which are thought to play important roles as risk factors for VAP in the early atheromatous lesion and in the future development of occlusive lesions when chronically present. 相似文献
992.
Tajima H. Moriyama M. Tadokoro N. Hara H. Mochizuki T. 《Quantum Electronics, IEEE Journal of》1992,28(6):1562-1570
Three-layer composite glass slab lasers were fabricated using optical contact and thermal fusion methods, and their characteristics were examined in an attempt to develop a high-peak-power glass laser able to deliver a high-quality beam at a high repetition rate operation. The optical characteristics, laser characteristics, and limitation of the output of these composite slabs and the monolithic slab are compared. It is found that thermal birefringence effects were reduced in the case of the composite slabs in comparison to the monolithic slab at the same output during repetitive operation, thereby maintaining a high level of beam quality. A doping amount of Nd2O3 of 6 wt.% was optimum for increasing the single pass gain of the composite slabs. An optimum thickness of doping layer exists for keeping gain high while maintaining thermal birefringence effects at a low level 相似文献
993.
Shiota F. Nakayama K. Nezu Y. Endo T. Sakamoto Y. Kikuzawa M. Hara K. 《IEEE transactions on instrumentation and measurement》1989,38(2):225-228
An improvement of the preliminary superconducting magnetic levitation system for the absolute determination of the magnetic flux quantum is described. This improvement includes the development of the flux-up method to determine the flux in terms of the Josephson voltage. The improvement is essential for the determination of the magnetic flux quantum as well as of the coil current, in terms of the Josephson voltage and quantized Hall resistance 相似文献
994.
A high-density polyethylene prepared at low pressures is characterized with respect to density, microscopic examination, mechanical properties, and diffusion. The data for the slowly cooled, nonisothermally crystallized polymer clearly indicate that the method of preparation grossly affects the final properties of the polymer. 相似文献
995.
Dynamics of dissolved oxygen during an algal bloom were studied in Lake Kasumigaura. Great amounts of oxygen arose from photosynthesis, and the concentration of dissolved oxygen reached 190% of saturation at 12 h. The majority of the dissolved oxygen produced was liberated into the atmosphere or consumed by microorganisms. Only minor fractions were transported into the dysphotic zone due to the low eddy diffusion coefficient in deeper waters of the euphotic zone. 相似文献
996.
997.
Hara A Ueda M Matsui T Furuhashi K Kanayama N Tanaka A 《Journal of Bioscience and Bioengineering》1999,87(6):717-720
A transformation system using the autonomously replicating plasmid in the n-alkane-assimilating and asporogenic diploid yeast, Candida tropicalis, was developed. For the cloning of a DNA fragment containing a potential autonomously replicating sequence (ARS) from the genomic DNA of C. tropicalis, the ura3 mutant obtained using ethylmethane sulfonate as the host and the URA3 gene amplified by PCR using the C. tropicalis genomic DNA as a selectable marker were prepared. Comparison of ARSs among yeasts revealed that the consensus sequence found in S. cerevisiae was also present in C. tropicalis. The autonomously replicating plasmid containing the putative ARS as the shuttle vector, capable of replicating in both E. coli and C. tropicalis, was first constructed. The transformation system using this plasmid, in addition to the integrative transformation system, will be applicable to genetic studies of C. tropicalis. 相似文献
998.
Nicholas Dunne Valerie Jack Rochelle O’Hara David Farrar Fraser Buchanan 《Journal of materials science. Materials in medicine》2010,21(8):2263-2270
The strategic incorporation of bioresorbable polymeric additives to calcium-deficient hydroxyapatite cement may provide short-term
structural reinforcement and modify the modulus to closer match bone. The longer-term resorption properties may also be improved,
creating pathways for bone in-growth. The aim of this study was to investigate the resorption process of a calcium phosphate
cement system containing either in polyglycolic acid tri-methylene carbonate particles or polyglycolic acid fibres. This was
achieved by in vitro aging in physiological conditions (phosphate buffered solution at 37°C) over 12 weeks. The unreinforced
CPC exhibited an increase in compressive strength at 12 weeks, however catastrophic failure was observed above a critical
loading. The fracture behaviour of cement was improved by the incorporation of PGA fibres; the cement retained its cohesive
structure after critical loading. Gravimetric analysis and scanning electron microscopy showed a large proportion of the fibres
had resorbed after 12 weeks allowing for the increased cement porosity, which could facilitate cell infiltration and faster
integration of natural bone. Incorporating the particulate additives in the cement did not provide any mechanism for mechanical
property augmentation or did not demonstrate any appreciable level of resorption after 12 weeks. 相似文献
999.
Mayumi Inaba Kenichi Sugioka Takahiko Naruko Kei Yunoki Yasuyuki Kato Toshihiko Shibata Takeshi Inoue Masahiko Ohsawa Minoru Yoshiyama Makiko Ueda 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(3):632-640
A high prevalence and a rapid progression of aortic valve stenosis (AS) in patients undergoing hemodialysis (HD) has been reported. In these circumstances, intraleaflet hemorrhage of aortic valve may be related to the development of AS in HD patients. We immunohistochemically examined the relationship among intraleaflet hemorrhage, neovascularization, hemoglobin scavenger receptor (CD163), and heme oxygenase‐1 (HO‐1) using surgically resected aortic valve specimens from AS patients undergoing HD. The study population consisted of 26 HD patients and 25 non‐HD patients with severe AS who had undergone aortic valve replacement. Frozen aortic valve samples surgically obtained from AS patients were stained immunohistochemically with antibodies against smooth muscle cells, macrophages, glycophorin‐A (a protein specific to erythrocyte membranes), CD31, CD163, and HO‐1. Morphometric analysis demonstrated that the CD163‐positive macrophage score, the number of CD31‐positive microvessels, and the percentage of glycophorin‐A and HO‐1‐positive area were significantly higher in HD patients than in non‐HD patients (CD163‐positive macrophage score, P < 0.0001; CD31‐positive microvessels, P < 0.0001; glycophorin‐A, P < 0.0001; HO‐1, P < 0.0001). Double immunostaining for CD163 or HO‐1 and macrophages revealed that the majority of CD163‐ or HO‐1‐positive cells were macrophages. Furthermore, CD163‐positive macrophage score was positively correlated with glycophorin‐A, HO‐1‐positive area, and the number of CD31‐positive microvessels (glycophorin‐A, R = 0.66, P < 0.0001; HO‐1, R = 0.50, P < 0.0005; microvessels, R = 0.38, P < 0.01). These findings suggest a positive association among intraleaflet hemorrhage, neovascularization, and enhanced expression of CD163 and HO‐1 as a response to intraleaflet hemorrhage in stenotic aortic valves in AS patients undergoing HD. 相似文献
1000.
An efficient critical control system design is proposed in this paper.The key idea is to decompose the design problem into two simpler design steps by the technique used in the classical loop transfer recovery method (LTR).The disturbance cancellation integral controllcr is uscd as a basic controller.Since the standard loop transfer recovery method cannot bc applied to the disturbance cancellation controller, the nonstandard version recently found is used for the decomposition.Exogenous inputs with constraints both on the amplitude and rate of change are considered. The majorant approach is taken to obtain the analytical sufficient matching conditions.A numerical design example is presented to illustrate the effectiveness of the proposed design. 相似文献