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排序方式: 共有4584条查询结果,搜索用时 15 毫秒
31.
T Yokoyama H Gondo Y Tanaka K Takenaka K Tanimoto M Nakamura Y Niho 《Canadian Metallurgical Quarterly》1996,37(4):358-361
A 62-year-old Japanese man complained of fever, general fatigue, anorexia and watery diarrhea during remission of adult T-cell leukemia-lymphoma. Laboratory examinations showed severe hypoproteinemia (2.9 g/dl). However, neither intestinal lesions associated with ATL nor findings suggesting protein losing gastroenteropathy were observed. Cytomegalovirus (CMV) antigen detection assay using peripheral blood leukocytes revealed that he had an active CMV infection with hemophagocytic syndrome. Treatment with ganciclovir and methylprednisolone led to an improvement of hypoproteinemia. CMV disease and associated hemophagocytic syndrome should be considered as a cause of hypoproteinemia in an immunocompromised host. 相似文献
32.
Morihiko Nakamura Naoyuki Itoh Kenki Hashimoto Tokuzo Tsujimoto Toshiyuki Suzuki 《Metallurgical and Materials Transactions A》1994,25(2):321-330
Isothermally forged TiAl-base alloys (Al-rich, Mn-containing, and Cr-containing TiAl) were heat-treated in various conditions,
and equiaxed grain structures consisting of γ and α2 or Β phases were obtained. The heat-treated alloys were tensile tested in vacuum and air at room temperature, and the environmental
effect on tensile elongation was studied. The ductility of the alloys consisting of equiaxed γ grains and a large amount of
α2 grains was not largely affected by laboratory air, and a decrease in the amount of α2 grains resulted in a large reduction of ductility in air. The Β phase in the Cr-containing alloy improved the ductility in
vacuum, but it resulted in a large reduction of ductility in air.
Formerly with Kougakuin University, Shinjyuku-ku, Tokyo,
Formerly with National Research Institute for Metals, Meguro-ku, Tokyo, 相似文献
33.
Masaaki Miyamoto Hiroyuki Koike Toshio Sada Yasuteru Ijima Junichiro Fukushige Norio Nakamura 《Lipids》1991,26(12):1316-1319
Platelet-activating factor (PAF) is a potent inflammatory mediator which is released by various inflammatory cells and produced
by certain tissues, including the kidney. PAF has been shown to increase glomerular permeability to protein and to decrease
glomerular filtration rate (GFR) by contracting mesangium. On the basis of these observations, it has been suspected that
PAF may play a role as mediator of glomerular damage in glomerular nephritis. To examine this possibility, we studied the
effects of a specific PAF antagonist, R-75,317, on the development of an experimental model of anti-glomerular basement membrane
(anti-GBM) glomerulonephritis. Glomerulonephritis was initiated by injecting rabbit anti-rat GBM serum into rats. Proteinuria
gradually developed after serum injection, plateaued at week 2, and remained at the high level of week 2 throughout the experimental
period (6 wk). Chronic treatment with R-75,317 (10 mg/kg/day i.p.) tended to delay the onset of proteinuria and significantly
accelerated the recovery phase. Creatinine clearance (Ccr) fell to 40% at week 3. R-75,317 treatment completely prevented
this decline of Ccr. Histological changes in this model (glomerular hypertrophy, proliferation of mesangial matrix and interstitial
fibrosis) were also ameliorated by the R-75,317 treatment. The results suggest that PAF may play a role in the development
of glomerulonephritis and that PAF antagonists could be used in the treatment of human renal disease.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, May 1989. 相似文献
34.
Y. Nakamura Ichiro Tanaka N. Takeuchi S. Koshiba H. Sakaki 《Journal of Electronic Materials》1998,27(11):1240-1243
We studied morphology of GaAs surfaces and the transport properties of two-dimensional electron gas (2DEG) on vicinal (111)B
planes. Multi-atomic steps (MASs) are found on the vicinal (111)B facet grown by molecular beam epitaxy, which will affect
electron transport on the facet. We also studied how the morphology of GaAs epilayers on vicinal (111)B substrates depends
on growth conditions, especially on the As4 flux. The uniformity of MASs on the substrates have been improved and smooth surfaces were obtained when the GaAs was grown
with high As4 flux, providing step periodicity of 20 nm. The channel resistance of the 2DEG perpendicular to the MASs is reduced drastically
with this smooth morphology. These findings are valuable not only for fabricating quantum devices on the (111)B facets but
also those on the vicinal (111)B substrates. 相似文献
35.
Ogi H. Nakamura N. Sato K. Hirao M. Uda S. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(5):553-560
This paper presents advanced techniques to determine all independent elastic-stiffness coefficients C/sub ij/, the associated internal friction Q/sub ij//sup -1/, and piezoelectric coefficients e/sub ij/ of monocrystal langasite (La/sub 3/Ga/sub 5/SiO/sub 14/) using a single rectangular parallelepiped specimen. Langasite's crystal structure belongs to the trigonal system with point group 32, and thus possesses six independent C/sub ij/, two e/sub ij/, and two dielectric coefficients /spl epsiv//sub ij/. All of the elastic and piezoelectric coefficients affect the mechanical resonance frequencies of the solid specimen, and measuring them very accurately permits one to determine the C/sub ij/ and e/sub ij/ with known density, dimensions, and e/sub ij/. We developed a piezoelectric tripod to support the specimen upward and measured the free-vibration resonance frequencies with minimum load from its own weight. This weak and stable acoustic coupling ensures accuracy of the frequency measurement better than 10/sup -5/, enough to determine the coefficients reliably. Our C/sub ij/ fall in the range of results measured with previous (conventional) methods. Our e/sub 11/ is smaller than the reported values by 1.2-13%, and e/sub 14/ is larger by 44-97%. For the internal friction measurement, we used a solenoid coil to vibrate the specimen without any contact. The longitudinal-wave internal friction considerably exceeds the shear-wave internal friction, which can be explained by phonon-phonon interactions. 相似文献
36.
Immunoassay method for the determination of immunoglobulin G using bacterial magnetic particles. 总被引:7,自引:0,他引:7
We have developed a novel immunoassay method using bacterial magnetic particles for the determination of immunoglobulin G (IgG). Fluorescein isothiocyanate (FITC) conjugated anti IgG-bacterial magnetic particles were prepared. The fluorescence quenching caused by agglutination of FITC-anti IgG antibody-bacterial magnetic particle conjugates was measured by using a fluorescence spectrophotometer. The aggregates based on specific immunoreaction were separated by a gelatin solution. The aggregation of bacterial magnetic particle conjugates was enhanced by application of a magnetic field. The relative fluorescence intensity correlated linearly with a concentration of IgG in the range 0.5-100 ng/mL. 相似文献
37.
38.
Frequency-shifted feedback (FSF) laser exhibits outstanding features in its oscillation spectrum. We analyze build-up dynamic properties of the FSF laser by means of rate equation and analyze steady-state dynamic properties of the FSF laser by means of Wigner-Ville distribution of intracavity electric field. Furthermore, we analyze instantaneous oscillation frequency at peak spectral intensity and oscillation bandwidth of its spectrum using the formula of instantaneous spectral intensity derived from Wigner-Ville distribution of intracavity electric field. These analytical results are in good agreement with the experimental ones which have been observed by a diode-pumped Nd:YVO4 FSF laser. It becomes clear that the FSF laser supports many frequency components simultaneously even though the gain medium is homogeneously broadened and has a continuously chirped frequency components of comb in which the creation of chirped frequency components are strongly correlated in phase because of a replica of the preceding components. Also, the instantaneous oscillation frequency is closely related to the detuning frequency which depends on the total net gain in the cavity and the gain bandwidth of atomic transition. The oscillation bandwidth is defined as the product of the saturation-broadened bandwidth and the total resonant modes contributing to FSF operation 相似文献
39.
T Kataoka M Wachi J Nakamura S Gayama M Yamasaki K Nagai 《Canadian Metallurgical Quarterly》1993,194(3):1420-1426
In an in vitro assay, the oriC DNA has been shown to bind to the outer membrane fraction only when it is hemimethylated (G.B. Ogden et al., Cell, 54, 127-135,1988). In this report, however, we demonstrated that a significant amount of the oriC DNA was recovered from the cells just before initiation with the oriC DNA being fully methylated. Formation of this preinitiation oriC-membrane complex and following initiation of chromosome replication were strongly inhibited by novobiocin, a DNA gyrase B subunit inhibitor, which reduced the superhelicity of the reporter plasmid in the cells. On the other hand, both reactions proceeded in the presence of nalidixic acid, a DNA gyrase A subunit inhibitor, which did not have the effect of reducing the superhelicity. These results suggest that the negative superhelicity of the DNA is required for preinitiation oriC-membrane complex formation and following initiation event of replication. 相似文献
40.
T. S. Saitoh M. Nakamura T. Gomi 《International journal for numerical methods in engineering》1994,37(11):1793-1805
In this paper, the time–space method (TSM) for multidimensional melting and solidification problems is proposed. In the proposed TSM, the timewise co-ordinate is incorporated into one of the spatial co-ordinates, thereby transforming the usual transient 2-D (or 3-D) problems into steady 3D (or 4-D) boundary-value problems. Since time integration is not necessary, the TSM has a feature that eliminates the so-called numerical instability which has been a great concern in the principal numerical methodologies in the past. That is, no error propagation in the timewise direction occurs in the TSM calculation. The TSM is applicable to almost all transient heat transfer and flow problems. The computer running time will be reduced to only 1/100th–1/1000th of the existing schemes for 2-D or 3-D problems. The sample calculations are presented for a 2-D melting problem in a square cavity and the validity of the present method is examined. 相似文献