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排序方式: 共有610条查询结果,搜索用时 15 毫秒
221.
Y Soejima A Niwa M Tanaka M Doi M Nitta T Takamoto M Hiroe F Marumo T Shirai M Watanabe A Suzuki 《Canadian Metallurgical Quarterly》1996,35(5):380-382
A 79-year-old male, admitted because of severe dyspnea on exertion, showed echocardiographic findings of a large tumor in the dilated right ventricle. The right ventricular outflow tract was nearly occluded by the tumor mass, and the mass was attached to the interventricular septum by a pedicle. The tumor removal operation was successful. The size of the tumor was 40 mm x 90 mm, and the weight 70 g. Microscopic findings showed typical myxomatous tissue with high cellularity, and no malignancy was observed. This is the oldest reported patient with right ventricular myxoma which was cured by operation. 相似文献
222.
M Sunamoto K Kuze H Tsuji N Ohishi K Yagi K Nagata T Kita T Doi 《Canadian Metallurgical Quarterly》1998,78(8):967-972
Heat shock protein 47 (HSP47) is a collagen-specific molecular chaperone that has been shown to play a major role during the biosynthesis and secretion of procollagen molecules. The expression of HSP47 has been reported to increase in parallel with the expression of collagens during the progression of various fibrosis models. However, it remains unclear whether an inhibition of HSP47 overexpression would suppress collagen accumulation and thus reduce the progression of fibrotic diseases. In this study, we attempted to attenuate glomerular collagen accumulation by inhibiting the overexpression of HSP47 with antisense oligodeoxynucleotides in an experimental glomerulonephritis model induced by anti-Thy-1 antibodies. The administration of antisense oligodeoxynucleotides against HSP47 at the induction of the glomerular disease markedly suppressed the increased production of collagens and attenuated the histologic manifestations of the disease. These results provide direct evidence of a pivotal role for HSP47 in the pathogenesis of glomerulonephritis. 相似文献
223.
Widely (132 nm) wavelength tunable laser using a semiconductor optical amplifier and an acousto-optic tunable filter 总被引:1,自引:0,他引:1
Takabayashi K. Takada K. Hashimoto N. Doi M. Tomabechi S. Nakazawa T. Morito K. 《Electronics letters》2004,40(19):1187-1188
A widely wavelength tunable laser combining a semiconductor optical amplifier, an acousto-optic tunable filter and a Fabry-Perot etalon has been developed. It exhibited good characteristics over a 132 nm (1480-1612 nm) tuning range. 相似文献
224.
The mechanism of stereospecific polymerization of propylene (catalysed by a modified Ziegler-Natta system, TiCl4/MgCl2/C6H5COOC2H5/Al(C2H5)3), has been analysed using the values of triad and pentad tacticity determined using 125 MHz 13C n.m.r. spectroscopy. The well-known single active-site models, such as the Bernoullian, first- and second-Markovian, and enantiomorphic models, were found to be inadequate to describe the observed tacticity. A two-sites model, in which at one site the stereospecific polymerization proceeds in obedience to the Bernoullian model and at the other proceeds under the control of enantiomorphic-site model, is proposed. It was found that the pentad tacticities of both soluble and insoluble (in boiling heptane) fractions of polypropylene agreed well with the two-sites model. 相似文献
225.
H Oana RW Hammond JJ Schwinefus SC Wang M Doi MD Morris 《Canadian Metallurgical Quarterly》1998,70(3):574-579
Capillary electrophoresis in dilute and semidilute (slightly entangled) hydroxyethyl cellulose (HEC) is shown to separate linear double-stranded DNA (ds-DNA) and supercoiled plasmid DNA in the size range 1-16 thousand base pairs in 3 min. The mobilities of linear ds-DNA fragments are stronger functions of electric field strength and buffer concentration than the mobilities of supercoiled plasmids. The effects of HEC concentration and molecular weight are similar for both forms of DNA. The behavioral differences, which are attributed to the greater stiffness of the plasmids, can be used to define conditions that maximize resolution of supercoiled and linear ds-DNA of the same or similar number of base pairs. 相似文献
226.
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228.
Akira Doi 《Journal of Materials Science》1987,22(12):4377-4380
A novel view is presented on the origin of thermal and intrinsic breakdowns from the analysis of published data for pynax glass and several polymers. For the former, the Origin is not due to failure of thermal balance between joule heating and its dissipation, but to charge injection from the anode, by which the current surge to the cathode is afforded and, when the cathode cannot accommodate the neutralized charge carriers, those neutralized species would pile up and advance the cathode-front back to the anode and, finally, a filamentary conductive path is constructed between the electrodes. It is suggested that the occurrence of intrinsic breakdown is determined by the number of electrons which are injected from the cathode by tunnelling because an individual electron gives rise to a certain amount of damage on its passage through the insulator by momentum transfer. From the analysis of time delay before the onset of breakdown, we can estimate the electron affinity of an insulator. 相似文献
229.
S Nomoto G Massa F Mitani Y Ishimura K Miyahara K Toda I Nagano T Yamashiro S Ogoshi J Fukata S Onishi K Hashimoto Y Doi H Imura Y Shizuta 《Canadian Metallurgical Quarterly》1997,234(2):382-385
Corticosterone methyloxidase I (CMO I) deficiency is an autosomal recessive disorder of aldosterone biosynthesis. To determine further the molecular genetic basis of CMO I deficiency, a patient of Turkish origin that suffered from CMO I deficiency was studied. Nucleotide sequencing of the PCR-amplified exons from the genomic DNA of this patient revealed a single point mutation CTG (leucine) CCG (proline) at codon 461 in exon 8 of CYP11B2, which is involved in the putative heme binding site of steroid 18-hydroxylase (P450(C18)). The expression study using a cDNA introducing the point mutation revealed that the amino acid substitution totally abolishes the P450(C18)p3 enzyme activities required for conversion of 11-deoxycorticosterone to aldosterone, even though the mutant product was detected in the mitochondrial fraction of the transfected cells. These results suggest that this point mutation causes CMO I deficiency. 相似文献
230.
Tokuyama Soda Co. ltd. has developed an energy-saving skid mounted electrodialyzer for sea water desalination. This equipment is suitable for making fresh water for drinking and industrial use. To desalinate 25°C sea water and turn out one ton of product water. This equipment consumes only 8.5 KWH of electricity and 0.09 Kg of concentrated sulfuric acid. Low energy consumption is achieved by adoption of low electric resistance membranes, new spacer and new designed one pass type system. Low running cost, easy maintenance and low initial installment cost place the equipment good position in the desalination field. And also we applied high temperature electrodialysis up to 50°C of sea water and get figure 6.0 KWH for one ton of product water. 相似文献