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排序方式: 共有6135条查询结果,搜索用时 224 毫秒
81.
H Imano H Iso T Tanigawa T Sankai T Ohira M Kudo T Shimamoto S Sato T Okamura M Iida 《Canadian Metallurgical Quarterly》1998,45(6):536-551
To investigate the contribution of the platelet aggregation in the development of cardiovascular diseases, we examined the relation of constitutional and lifestyle variables with platelet aggregation for a total of 306 males aged 50 to 70 in Ikawa town, Akita prefecture (n = 163) and Noichi town, Kochi prefecture (n = 143). The examination of platelet aggregation was completed within 3 hours of obtaining blood samples. We used ADP (Adenosine 5'-diphosphate) as an agonist and obtained PATI (the platelet aggregatory threshold index) by nephelometry. Platelet count, mean platelet volume, white blood cell count, serum fatty acid compositions were also examined and dietary intake of fish, seafood and soy bean foods were inquired using one-week dietary records. PATI indicated a logarithmic normal distribution in both Ikawa and Noichi. The mean of logarithmic transformed PATI (log PATI) was higher in Ikawa than in Noichi. Thus platelet aggregation was lower in Ikawa than in Noichi. According to multiple regression analysis, age, platelet count in platelet rich plasma, mean platelet volume in platelet rich plasma, and white blood cell count were inversely associated with log PATI. Serum arachidonic acid composition tended to be inversely related with log PATI. Serum n3-polyunsaturated fatty acid composition was positively related with log PATI, and log gamma-GTP tended to be positively associated with log PATI. Soy protein intake and cigarette smoking showed no consistent associations with log PATI. This cross-sectional study suggests that serum n3-polyunsaturated fatty acid, and gamma-GTP, as an index of alcohol intake, reduce platelet aggregation while age, white blood cell count, platelet count, mean platelet volume, and serum arachidonic acid raise platelet aggregation. 相似文献
82.
Y. Yoshimura T. Sato H. Shimada N. Matsubayashi M Imamura A. Nishijima M. Higo S. Yoshitomi 《Catalysis Today》1996,29(1-4):221-228
Nickel-tungstate/γ-alumina (NiW) catalysts were prepared by an incipient wetness impregnation method using citric acid as a complexing agent. Citric acid has been used by our research group in preparing cobalt-molybdate and nickel -molybdate catalysts. The extended X-ray absorption fine structure (EXAFS) data of the impregnating solutions indicated that citric acid contributes to the formation of polytungstate anions that are smaller than the dodecatungstate ions formed when conventional ammoniacal solutions are used. Sulfided NiW catalysts prepared by using citric acid showed higher hydrogenation activity and hydrogenation selectivity than NiW catalysts prepared using the conventional ammoniacal solutions. 相似文献
83.
84.
S Murakami I Yamagishi Y Asami M Sato K Tomisawa 《Canadian Metallurgical Quarterly》1996,42(6):865-872
The effects of a novel acyl-CoA: cholesterol acyltransferase (ACAT) inhibitor, HL-004, on cholesterol metabolism were examined in mice peritoneal macrophages. Cholesteryl ester-rich foam cells were induced by incubating macrophages with acetylated LDL. HL-004 prevented the accumulation of cholesteryl ester in the presence of the cholesterol acceptor, HDL. In the absence of HDL, HL-004 generated large amounts of free cholesterol in the cell. Moreover, HL-004 stimulated the efflux of cholesterol from preestablished foam cells in the presence of HDL. These results suggest that the inhibition of foam cell formation and the stimulation of foam cell regression by HL-004 are attributed to intracellular ACAT inhibition, and that HL-004 would be expected to exhibit an antiatherosclerotic effect through direct action on arterial wall. 相似文献
85.
In leukocytes such as thymocytes and basophilic leukemia cells, a glycosilated integral membrane protein called CD43 (leukosialin or sialophorin), which is defective in patients with Wiskott-Aldrich syndrome, was highly concentrated in the cleavage furrow during cytokinesis. Not only at the mitotic phase but also at interphase, CD43 was precisely colocalized with ezrin-radixin-moesin family members. (ERM), which were previously reported to play an important role in the plasma membrane-actin filament association in general. At the electron microscopic level, throughout the cell cycle, both CD43 and ERM were tightly associated with microvilli, providing membrane attachment sites for actin filaments. We constructed a cDNA encoding a chimeric molecule consisting of the extracellular domain of mouse E-cadherin and the transmembrane/cytoplasmic domain of rat CD43, and introduced it into mouse L fibroblasts lacking both endogenous CD43 and E-cadherin. In dividing transfectants, the chimeric molecules were concentrated in the cleavage furrow together with ERM, and both proteins were precisely colocalized throughout the cell cycle. Furthermore, using this transfection system, we narrowed down the domain responsible for the CD43-concentration in the cleavage furrow. Based on these findings, we conclude that CD43 is concentrated in the cleavage furrow through the direct or indirect interaction of its cytoplasmic domain with ERM and actin filaments. 相似文献
86.
Y Sato S Miyazaki T Shikano N Mitsuhashi H Takeuchi K Mikoshiba Y Kuwabara 《Canadian Metallurgical Quarterly》1998,58(3):867-873
Relaxin plays a major role in promoting the growth and softening of the cervix that occurs during the second half of pregnancy in the rat. There is limited evidence that prostaglandins play a role in cervical softening in mammalian species. Accordingly, this study was conducted to determine if prostaglandins mediate relaxin's effects on the rat cervix. To attain that objective, indomethacin was used to inhibit cyclooxygenase, the key enzyme in the conversion of arachidonic acid to prostaglandins. Twenty-six nonpregnant female rats were ovariectomized when they were 78 days old (day 1 of treatment). At ovariectomy (O), each rat was fitted with silicon tubing implants containing progesterone (P) and estrogen (E) in doses that provided blood levels similar to those during late pregnancy in rats. Rats were randomly assigned to three treatment groups. Group OPE controls (n = 8 rats) received 2 ml indomethacin vehicle (0.5% methyl cellulose, 0.025 Tween 80 in water) via gavage at 0900 h on days 8 and 9 and 0.5 ml relaxin vehicle (0.9% NaCl) s.c. at 6-h intervals from 1200 h on day 8 through 0600 h on day 10. Group OPER (n = 9 rats) was treated as group OPE except that 20 microg highly purified porcine relaxin was administered. Group OPERI (n = 9 rats) was treated as group OPER except that indomethacin was administered at a dose (20 mg/kg BW) that reduced cervical PGE2 levels by more than 90%. Between 0800 h and 1000 h on day 10, the cervices were removed, trimmed of fat, weighed, and placed in ice-cold Krebs-Ringer bicarbonate buffer, pH 7.5. Cervical extensibility (degree of softening) was determined within 4 h of tissue collection. Both the mean cervical wet weight and the mean cervical extensibility in the relaxin-treated group OPER rats were markedly greater (P < 0.01) than in the group OPE controls. Treatment with indomethacin did not diminish relaxin's effects on either cervical wet weight or cervical extensibility. In conclusion, this study provides evidence that relaxin's effects on cervical growth and softening in the rat are not mediated through prostaglandins. 相似文献
87.
88.
A control method for current-type PWM AC-to-DC converters that realizes a sinusoidal AC input current and unity power factor is discussed in detail. In such converters, an LC filter placed on the AC side may cause a resonant problem, especially in the transient condition. To overcome this problem, state feedback control is introduced, and a control strategy suitable for DC-output current control as well as AC-side current control is proposed. Circuit parameters and feedback coefficients in the AC-side current control system are optimized on the basis of an analysis in which the system is treated as a sampled-data system. A method of investigating parameters in the DC-side current control system is shown. To confirm the effectiveness of the control strategy and the validity of the analytical results, an experimental investigation of the basic characteristics of the system is made. As an example, this system is applied to controlling the current waveform in the reactor. The experimental results for this application are also included 相似文献
89.
We developed a method that allows prenatal diagnosis of Duchenne muscular dystrophy using a single nucleated erythrocyte (NRBC) isolated from maternal blood. Maternal blood was obtained at 8 to 20 weeks of gestation. NRBCs were separated with Percoll using a discontinuous density gradient method and then collected by micromanipulator under microscopic observation. The entire genome of a single cell amplified by primer extension preamplification (PEP). Sex was determined from a small aliquot of the PEP reaction. After an NRBC was determined to be male and confirmed to be of fetal origin, dystrophin exons 4, 8, 12, 45, 48, 50, and 51 were determined from the same PEP reaction. This diagnostic method using maternal blood is safer than amniocentesis or cordocentesis and can be applied to other X-linked disease. 相似文献
90.
Stability of large-scale coal-fired MHD channels is studied by (1) linearized stability analysis, and (2) time-dependent 1-D analysis. The channel length is 15 m with 600 electrode pairs, and the output power ranges from 220.6 MW through 258.7 MW. Linearized stability analyses show that the Faraday channels operated with fixed loading resistance are stable, whereas the two waves of u and u–a (u, a: gas and sound velocity) become unstable in the Faraday channel with fixed loading factor. Two waves of u and u–a are unstable in the diagonal channel with fixed loading current and the u + a wave becomes unstable in the diagonal channel with fixed electrode current. Time-dependent one-dimensional analyses indicate that the Faraday channels with fixed load resistance are smooth without growth of fluctuation. The diagonal channels with fixed electrode current are smooth with no fluctuation, though the linear theory indicates that the u + a wave is unstable. The diagonal channel with fixed load current suffers large disturbance along the latter half of the channel, being consistent with the linearized analysis which indicates that the u - a and u waves are unstable. 相似文献