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101.
H Sao K Kitaori M Kasai T Shimokawa H Kato M Hayakawa C Kato T Yamaguchi Y Kamiya M Yanada Y Morishima 《Canadian Metallurgical Quarterly》1998,39(7):473-480
In this study, we examined the ability of tumour necrosis factor-alpha (TNF) to stimulate the mitogen-activated protein (MAP) kinase homologues p42/44 MAP kinase, c-Jun NH2-terminal kinase (JNK) and p38 MAP kinase and its effect upon DNA synthesis in primary cultures of bovine aortic endothelial cells (BAECs). TNF strongly stimulated p38 MAP kinase and JNK activity in both a time- and concentration-dependent manner. By contrast, TNF was a very poor activator of p42/44 MAP kinase relative to the known activator of p42/44 MAP kinase in endothelial cells, adenosine triphosphate (ATP). TNF-stimulated activation of p38 MAP kinase, and MAPKAP kinase-2, a known downstream target of p38 MAP kinase, was strongly inhibited by pre-incubation with the p38 MAP kinase inhibitor SB203580, whereas the minor activation of p42/44 MAP kinase was abolished by pre-incubation of the cell with the novel MAP kinase kinase 1 inhibitor PD098059. Addition of TNF resulted in a 50-60% decrease in DNA synthesis in BAECs. Pre-incubation with PD098059 or co-incubation with ATP failed to modify the inhibitory effect of TNF upon DNA synthesis. SB203580 reduced basal DNA synthesis by approximately 50%; however, if failed to modify the inhibition mediated by TNF. These results indicate that TNF strongly activates both p38 MAP kinase, JNK and, to a minor extent, p42/p44 MAP kinase. It is likely that only one of these kinases, JNK, plays a role in the regulation of DNA synthesis in these cells. 相似文献
102.
Ashawant Gupta Carmen Cook Len Toyoshiba Jianmin Qiao Cary Y. Yang Ken-Ichi Shoji Akira Fukami Takahiro Nagano Takashi Tokuyama 《Journal of Electronic Materials》1993,22(1):125-128
Characterization of a Si1−xGex layer formed by high-dose germanium implantation and subsequent solid phase epitaxy is reported. Properties of this layer
are obtained from electrical measurements on diodes and transistors fabricated in this layer. Results are compared with those
of the silicon control devices. It was observed that the germanium implantation created considerable defects that are difficult
to eliminate with annealing. These defects result in boron deactivation in the p-type regions of the devices, giving rise
to larger resistance. Optimization of the device structure and fabrication process is discussed. 相似文献
103.
Tomiji Wakida Huishun Li Yukihiro Sato Haruo Kawamura Mitsuo Ueda Haruo Mizushima Shoji Takekoshi 《Coloration Technology》1993,109(9):292-296
Polyester fabrics and films treated with two fluorocarbon resins were washed and heat treated. Water repellency, surface tension and ESCA measurements were carried out. Changes in the water repellency of the resin-treated polyester fabric caused by washing and heat treatment are related to modification of the chemical composition of the polyester surface. 相似文献
104.
OBJECTIVE: To determine the concentrations of beta-phenylethylamine (PEA) in CSF in patients with Parkinson's disease, and to evaluate the relation between concentration of PEA in CSF and severity of Parkinson's disease. METHODS: Using gas chromatography-chemical ionisation mass spectrometry, CSF concentrations of PEA were measured in 23 patients with Parkinson's disease (mean age, 64.0 (SD 8.2) years), of whom three were at Hoehn and Yahr stage II, 11 were at stage III, and nine were at stage IV. Comparison was made with eight patients with neuropathy (mean age, 57.0 (SD 19.2) years) and 12 controls without neurological disease (mean age, 57.6 (SD 4.8) years). RESULTS: Concentrations of PEA in CSF in Parkinson's disease were significantly lower (mean 205 (SD 131) pg/ml) than in patients with peripheral neuropathy (433 (SD 254) pg/ml) and controls (387 (SD 194) pg/ml). The concentrations of PEA in CSF correlated negatively with Hoehn and Yahr stage (P<0.01). CONCLUSIONS: There are decreased CSF concentrations of PEA in patients with Parkinson's disease. 相似文献
105.
106.
To evaluate the elastic-plastic fracture toughness parameter of nuclear pressure-vessel steel A533B-1, a newly developed technique (the recrystallization-etch technique) for plastic strain measurement was applied to different sizes of compact tension specimens with a crack length/specimen width of 0.6–0.5 that were tested to generate resistance curves for stable crack extensions. By means of the recrystallization-etch technique, the plastic energy dissipation or work done within an intense strain region at the crack tip during crack initiation and extension was measured experimentally. Furthermore, the thickness effects on this crack tip energy dissipation rate were examined in comparison with other fracture-parameter J integrals. Thickness effects on critical energy dissipation and energy dissipation rate during crack extension were obtained and the energy dissipation rate dW
p/da in the mid-section shows a constant value irrespective of specimen geometry and size, which can be used as a fracture parameter or crack resistance property. 相似文献
107.
Machiko Shimada Shoji Takigami Yoshio Nakamura Yukio Abe Toshi Iizuka Nobusuke Makiyama 《应用聚合物科学杂志》1993,48(6):1121-1126
Graft copolymerization of methyl methacrylate onto novoloid fiber was carried out by the electron beam mutual irradiation method. The characteristics of the grafted fiber were almost the same as those of the original novoloid fiber. The grafted fiber was carbonized and activated to yield an efficiently activated carbon fiber. The yield and the specific surface area of the activated carbon fiber, derived from the grafted novoloid fiber, were much greater than those derived from the original novoloid fiber. This is because grafted poly(methyl methacrylate) decomposes into monomer and gaseous products, forming pores on the surface and inside of the novoloid fiber on heating. © 1993 John Wiley & Sons, Inc. 相似文献
108.
This paper proposes a hybrid multiconverter system aiming at a large‐capacity high‐voltage high‐efficiency converter system free from harmonics in its input/output. The system consists of n (n: integer) GTO converters and a single neutral‐point‐clamped IGBT converter connected in series by n + 1 output transformers. The GTO converters operate in a square‐wave switching mode while the IGBT converter operates in a PWM switching mode. The former produces a base part of the resultant output voltage. The latter not only produces an additional part of the resultant output voltage, but offsets the voltage harmonics generated by the GTO converters. A basic voltage control strategy for the hybrid converter system is proposed, and its validity is verified by experimental results. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(3): 64–70, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20210 相似文献
109.
To remove endotoxin directly from the blood, an affinity adsorbent (PMX) has been developed. PMX is composed of a ligand of polymyxin B and a carrier of polystyrene fibers. We treated 16 patients, suffering from septic shock or multiple organ failure by PMX-F hemoperfusion. The pretreatment level of endotoxin decreased significantly from 80pg/ml to 21pg/ml on average 2 hours after the hemoperfusion. The hyperdynamic status in the cardiac index and the decreased systemic vascular resistance, which are characteristic to endotoxin shock, were normalized after the treatment. In septic shock patients with systolic pressure under 10mmHg, the systolic pressure increased significantly from pretreatment level. Nine of the sixteen patients remained alive for two weeks after the therapy, and seven out of the nine patients discharged alive. Hemoperfusion with PMX is likely to become an effective treatment for sepsis and septic shock. 相似文献
110.
A new group of magnetic circuits that can count the number of magnetic bubbles and display them in any binary, ternary, ..., decimal basis is proposed. Feasibility of the concept was demonstrated by successful operation of a binary counter circuit. A design of a decimal counter is given. 相似文献