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151.
S Sato M Fujimoto H Ihn K Kikuchi K Takehara 《Canadian Metallurgical Quarterly》1994,130(10):1273-1277
BACKGROUND AND DESIGN: Recently, we detected antihistone antibodies (AHAs) in patients with localized scleroderma. However, the exact antigen specificity of AHAs in this disease is still unknown. Therefore, we determined the reactivity of AHAs with five individual histones and the correlation of AHAs with rheumatoid factor in localized scleroderma by means of enzyme-linked immunosorbent assay. Twenty patients with localized scleroderma who had IgG and/or IgM AHAs, as determined by enzyme-linked immunosorbent assay, were examined. These patients were classified into the following three subgroups: patients with generalized morphea (n = 11), patients with linear scleroderma (n = 6), and patients with morphea (n = 3). RESULTS: In generalized morphea, IgG AHAs strongly reacted with histones H1, H2A, and H2B; and IgM AHAs strongly reacted with H1 and H2B, as determined by means of enzyme-linked immunosorbent assay. The pattern of reactivity in linear scleroderma and morphea was similar to that in generalized morphea. A homogeneous immunofluorescent pattern on HEp-2 cells, which was produced by localized scleroderma sera, was completely abolished by absorption with total histones. By employing a latex agglutination test, IgM rheumatoid factor was detected in 60% of the 20 patients with localized scleroderma and at a frequency of 82% in those with generalized morphea. However, an absorption test of rheumatoid factor activity with human IgG revealed no cross-reactivity of AHAs with rheumatoid factor. CONCLUSIONS: Our data suggest that AHAs in localized scleroderma are directed against native chromatin, since H1, H2A, and H2B occupy a relatively exposed portion of chromatin. 相似文献
152.
An 85-year-old male, who had undergone aorto-coronary bypass grafting to left anterior descending coronary artery (LAD) using saphenous vein graft (SVG) seventeen years before, was operated with minimally invasive direct coronary artery bypass grafting (MIDCAB) without cardiopulmonary bypass. LAD was anastomosed with the in situ left internal thoracic artery through a limited anterior thoracotomy. The postoperative angiography showed patent graft, and the patient has been doing well without any complications. MIDCAB is a useful technique even for re-operation of coronary diseases in selected cases. 相似文献
153.
T Inagaki T Niimi T Yamamoto Y Hashizume M Ogihara T Mizuno A Inagaki M Kikuchi 《Canadian Metallurgical Quarterly》1996,33(2):84-94
The purpose of this study was to assess the background to the longevity of 36 centenarians in Nagoya city and to compare 14 institutionalized centenarians out of those 36 with 202 individuals in the 70-99 age group in our special nursing home, particularly with regard to blood chemistry and immunity tests. The reasons for their social longevity in terms of profile appeared to be attention to eating habits, abstention from smoking and drinking, occupations with adequate exercise. The incidence of dementia was 65.6% among them. We evaluated centenarians from the viewpoint of Hasegawa's Dementia Scale (HDS) and comprehensive functional assessment of the elderly consisted of the revised version of Hasegawa's Dementia Scale (HDSR), and examination of activity of daily living (ADL), physical perception, and social life. All were positively associated. Thus centenarians independent of physical assistance demonstrated significantly higher systolic blood pressure, and respective scores for HDS, HDSR, ADL, physical perception and social life than their dependent counterparts, were less likely to be institutionalized and suffered from fewer disorders. In particular none were diagnosed as positive for cerebral hemorrhage, infarction and dementia. Age demonstrated significant positive or negative correlation with the following values in blood chemistry and immunity tests: blood cell counts, hemoglobin concentration, hematocrit value, albumin, total protein, total cholesterol, low density lipoprotein cholesterol, creatinine, blood cell nitrogen, uric acid, helper T cell, and IgA immunoglobulin. 相似文献
154.
155.
T Yamaki N Murakami Y Iwamoto T Sakakibara N Kobori S Ueda T Kikuchi Y Uwahodo 《Canadian Metallurgical Quarterly》1997,752(1-2):151-160
Enantiomer separations of various acidic racemates were performed by capillary electrophoresis (CE) using a commercial cationic beta-cyclodextrin (beta-CD), quaternary ammonium beta-CD (QA-beta-CD), and a commercial amphoteric beta-CD (AM-beta-CD) as chiral selectors. Eleven acidic racemates were successfully separated using QA-beta-CD by changing the CD concentration and the buffer pH. These enantiomer separations were compared with the results using five neutral CD derivatives. Although most racemates were separated with some of the neutral CDs, relatively high CD concentrations were required to obtain baseline separations. In contrast, when QA-beta-CD was employed, the enantiomer separations were successful at low concentrations below 5 mM. Enantiomers of five acidic racemates and ten dansylated amino acids (Dns-amino acids) were separated using AM-beta-CD. Although the baseline separation of racemic 4-chloromandelic acid was not achieved with either QA-beta-CD or five neutral CDs, AM-beta-CD showed complete resolution. Furthermore, the simultaneous enantiomer separation of eight Dns-amino acids was also achieved with AM-beta-CD. Both QA-beta-CD and AM-beta-CD were analyzed by CE and mass spectrometry (MS) in order to identify their compositions because they consisted of a mixture having different degrees of substitution. QA-beta-CD consisted of six components having from one to six quaternary ammonium groups. The composition of AM-beta-CD, however, was very complicated and could not be identified. 相似文献
156.
Performance analysis of variable optical delay circuit using highly nonlinear fiber parametric wavelength converters 总被引:1,自引:0,他引:1
Sakamoto T. Okada A. Moriwaki O. Matsuoka M. Kikuchi K. 《Lightwave Technology, Journal of》2004,22(3):874-881
The performance of a variable optical delay circuit that employs a fiber loop with highly nonlinear fiber parametric wavelength converters is discussed using both experiments and simulations. In our optical delay circuit, the delay time is determined from the number of circulations, which is controlled by the initially selected wavelength of the optical signal. We discuss the factors that limit the number of circulations described in our previous paper, derive the parameters that provide good performance levels, and confirm the performance by simulation. The simulated results indicate that 100 wavelength conversions can be achieved, namely, 100 different delay times can be given to optical packets. 相似文献
157.
158.
Ishihara N. Sano E. Imai Y. Kikuchi H. Yamane Y. 《Solid-State Circuits, IEEE Journal of》1992,27(4):554-562
A design procedure is proposed for a high-gain and wideband IC module, using stability analysis and a unified design methodology for ICs and packages. A multichip structure is developed using stability analysis and the requirements for stable operation are determined for each IC chip, package, and interface condition between them. Furthermore, to reduce the parasitic influences, several improvements in the interface and package design are clarified, such as wideband matching and LC resonance damping. IC design using effective feedback techniques for enlarging the bandwidth are also presented. The ICs are fabricated using 0.2-μm GaAs MESFET IC technology. To verify the validity of these techniques, an equalizer IC module for 10-Gb/s optical communication systems was fabricated, achieving a gain of 36 dB and a bandwidth of 9 GHz 相似文献
159.
Y Nakayama H Iwasaki S Iwanaga H Nakamura T Shiroshita M Kikuchi H Jozaki M Hashimoto S Ikeda 《Canadian Metallurgical Quarterly》1997,47(6):404-411
A rare case of spindle cell carcinoma (SpCC) of the breast occurring in a 51-year-old Japanese woman is reported. A firm and well-circumscribed tumor, measuring 9 x 8.5 x 8.5 cm, was located on the upper lateral region of the right breast. Microscopically, the tumor consisted of sheets of both malignant spindle cells and poorly differentiated ductal carcinoma containing squamoid islands with gradual transition to the spindle cell component. The immunocytochemical expression of epithelial markers was recognized in the spindle cells, as well as in the carcinomatous cells. Moreover, the spindle cell component expressed vimentin, alpha-smooth muscle actin and S-100 protein. Ultrastructurally, in addition to the features of adenocarcinoma, squamous or myoepithelial differentiation was confirmed in the spindle cell component. These findings thus suggest an epithelial origin with squamous differentiation and myoepithelial participation in the genesis of SpCC. In a comparative study, the expression of p53 protein and Ki-67 as a proliferation marker in each component of this tumor was also investigated. The mean p53 labeling index (LI) in both the carcinomatous and spindle cell area was similar, however the mean MIB-1 LI in the spindle cell area was significantly higher than that in the carcinomatous area. The results indicate that p53 overexpression is involved in the tumorigenesis of both components in the SpCC, and the spindle cell component shows a higher degree of proliferative activity than the carcinomatous component. 相似文献
160.
In this paper, the optical amplifier noise accumulation in long-distance optical transmission systems is analyzed under the influence of the parametric process caused by the Kerr effect and group-velocity dispersion. By considering the input signal as a continuous-wave (CW) carrier and the optical amplifier noise as the small modulation, the general theory on the evolution of the optical amplifier noise along the system is proposed. This theory enables us to treat all of the noise enhancement effects, the so called parametric instability, discussed so far in a unified manner. The validation of the theory is finally confirmed by using extensive computer simulations 相似文献