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排序方式: 共有640条查询结果,搜索用时 31 毫秒
1.
Tsukada T. Hashimoto Y. Sakata K. Okada H. Ishibashi K. 《Solid-State Circuits, IEEE Journal of》2005,40(1):67-79
A decoupling circuit using an operational amplifier is proposed to suppress substrate crosstalk in mixed-signal system-on-chip (SoC) devices. It overcomes the parasitic inductance problem of on-chip capacitor decoupling. The effect of the proposed decoupling circuit is not limited by parasitic fine impedance. A 0.13-/spl mu/m CMOS test chip showed that substrate noise at frequencies from 40 MHz to 1 GHz was incrementally suppressed by sequentially activating three of the proposed circuits in parallel. The power dissipation of each circuit was 3.3 mW at a 1.0-V power supply. The test chip measurement showed that the proposed decoupling reduced crosstalk by 31% at 200 MHz, whereas it was reduced by 4.4% with capacitor decoupling. This 7:1 ratio, or 17 dB, corresponds to the gain of the opamp. Design of the opamp and its feedback loop for active decoupling is simple, making the opamp useful for SoC applications. 相似文献
2.
M Ogihara K Aikawa K Ishibashi O Yamaguchi Y Shiraiwa K Koseki 《Canadian Metallurgical Quarterly》1997,43(8):555-560
We investigated the clinical usefulness of individualization of chemotherapeutic regimen in neoadjuvant intra-arterial chemotherapy for locally invasive bladder cancer. Anticancer drugs were selected according to the results of an in vitro chemosensitivity test (collagen matrix assay or succinic dehydrogenase inhibition test). Nine patients with locally invasive bladder cancer received 1 to 4 courses of neoadjuvant intra-arterial chemotherapy, followed by radical cystectomy. Histopathological responses in the cystectomized specimens were grade 3 in 3 cases, grade 2 in 2, grade 1b in 2 and no response in 2. Pathologically, a complete response and downstaging were observed in 3 and 4 cases, respectively. Seven of the 9 patients were alive no evidence of disease with a mean follow-up period of 38.9 months, whereas 2 patients died of metastasis within 2 years. Six of the 7 patients who showed a complete response or down staging have been free of recurrence. These findings suggest that our chemotherapeutic strategy may improve the prognosis for locally invasive bladder cancer. 相似文献
3.
4.
Y Ichiki S Shimoda H Hara H Shigematsu M Nakamura K Hayashida H Ishibashi Y Niho 《Canadian Metallurgical Quarterly》1997,26(3):728-733
T-cell-mediated autoimmune mechanisms are considered to be involved in the pathogenesis of primary biliary cirrhosis (PBC). In the previous study, we identified the immunodominant T-cell epitope on the E2 component of pyruvate dehydrogenase complex (PDC-E2) in patients with PBC who have HLA-DRB4*0101. In this report, we revealed that the frequency of the T cells reactive to the human PDC-E2 163-176 peptide is significantly increased in the peripheral blood of patients with PBC as compared with healthy subjects. We also confirmed that these T cells were all restricted with HLA-DRB4*01 (DR53) by using HLA-DR-transfected L cells. These results together with the evidence that the immunodominant B-cell epitope overlaps with the human T-cell epitope of the PDC-E2 antigen indicate that the T cells reactive to this epitope are closely associated with the pathogenesis of PBC at least in patients who have HLA-DR53. Therefore, we analyzed the T-cell receptor (TCR) Vbeta sequence of the five different T-cell clones and the three T-cell clones derived from three patients with PBC and healthy subjects, respectively, which are reactive to the human PDC-E2 163-176 peptide in the context of HLA-DR53. The Vbeta- and the Jbeta-gene usages were diverse among the T-cell clones (Vbeta11-Jbeta1.4, Vbeta8-Jbeta1.2, Vbeta12-Jbeta2.1, Vbeta10-Jbeta1.5, and Vbeta20-Jbeta2.1) in patients with PBC. By contrast, in the third complementarity determining region (CDR3), G was frequently found and GXG or GXS motif was identified in all T-cell clones. Moreover, RGXG motif was found in three clones generated from two patients. In healthy subjects, the Vbeta- and the Jbeta-gene usages were also diverse, and GXG and RGXG motif were found. These results indicate that the T cells may recognize the ligand (the human PDC-E2 163-176 peptide/HLA-DR53 complex) using the limited motif in the CDR3 region and that the design of CDR3-specific immunotherapy would be possible using these motifs. 相似文献
5.
Effects of non-Gaussian concentration fluctuations in real time photon correlation spectroscopy were investigated with several sizes of mono-disperse polystyrene latex particles. The non-Gaussian correlation model for a full or a quasi-full (scaled) correlator showed good performance for particle sizing in the case of scaled correlation. The clipped correlation showed an equivalent performance with the scaled correlation except for the case of non-Gaussian fluctuation, where the measured diameter became inaccurate more rapidly with decreasing particle concentration in the scattering volume. The cause of such an instability of PCS in the clipped mode is attributed to baseline fluctuations of the correlogram induced by information loss of the clipped correlator. 相似文献
6.
F Imai T Suzuki T Ishibashi M Tanaka Y Akiyama Y Dohi 《Canadian Metallurgical Quarterly》1994,21(4):612-615
OBJECTIVE: We investigated the in vitro immunomodulatory effects of sulfasalazine on B cells in rheumatoid arthritis (RA). METHODS: Reversed hemolytic plaque assay and 3H-thymidine incorporation were measured. RESULTS: B cells from patients with RA showed hyperactivity to stimulation by Staphylococcus aureus Cowan I. Sulfasalazine significantly inhibited this B cell hyperactivity in a dose dependent manner. The kinetic study and a decrease in 3H-thymidine incorporation on Day 3 indicate that sulfasalazine inhibited the early phase (0-48 h) of B cell proliferation in these patients. Sulfapyridine also inhibited B cell hyperactivity in these patients, but 5-aminosalicylic acid and N-acetylsulfapyridin had no significant effect. CONCLUSION: Sulfasalazine exhibited a direct immunosuppressive effect on B cell hyperactivity in patients with RA, which may be responsible for its therapeutic effectiveness in this disorder. 相似文献
7.
Akira Ishizaki Kazuhiko Takasaki Shoji Shimomura Kouichi Masaki Kanji Kitazawa 《Electrical Engineering in Japan》1996,116(5):128-137
Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos θ, where θ represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the aforementioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy. 相似文献
8.
K. Nakano S. Tomiya M. Ukita H. Yoshida S. Itoh E. Morita M. Ikeda A. Ishibashi 《Journal of Electronic Materials》1996,25(2):213-216
Using electroluminescence (EL) topography and transmission electron microscopy (TEM), we investigated the nonluminescent regions
which form while current is being injected into ZnMgSSe/ZnSSe/ZnCdSe-based blue light emitters. Small dark spots were observed
just after turn-on and spread out forming rough nonluminescent triangles in the <100> directions in the EL image of the active
region. TEM studies showed that the small dark spots are pre-existing stacking faults originating at the substrate/epitaxial
layer interface. The nonluminescent triangles were found to be a dense region of dislocation dipoles and dislocation loops.
Each dipole was aligned along two <110> directions in the {111} planes. The Burgers vectors were of the type a/2<011> inclined
at 45° to the (001) junction plane. 相似文献
9.
H Kusaba J Kudo T Kuruma R Nagashima M Ra T Mori Y Kaji H Ishibashi Y Niho Y Baba 《Canadian Metallurgical Quarterly》1993,84(6):330-333
Cardiotoxicity of interferon-alpha or gamma, such as fatal arrhythmia and myocardial infarction, has been reported. Therefore cardiotoxicity of interferon should be seriously considered before administration for patients with a pre-existing heart disease. We treated a patient with chronic active hepatitis type B, coexisted with Wolff-Parkinson-White syndrome, who has had frequent attacks of paroxysmal atrial fibrillation. To prevent the occurrence of fatal arrhythmia with an interferon therapy in this patient, we performed radiofrequency catheter ablation of the Kent bundle. After the successful ablation, we could safely administered recombinant interferon alpha-2b for chronic hepatitis type B. 相似文献
10.