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排序方式: 共有542条查询结果,搜索用时 109 毫秒
61.
Y Nakamura K Sakata T Ojima S Tanihara H Yanagawa 《Canadian Metallurgical Quarterly》1997,44(4):265-272
Virological response to treatment of chronic hepatitis B is defined as the loss of serum hepatitis B virus DNA (HBV DNA) and hepatitis B e antigen (HBeAg). The quantitative measurement of HBV DNA is useful for monitoring and predicting the response to therapy with interferon-alpha (IFN-alpha). In this study, we evaluated whether quantitative measurement of serum HBeAg and IgM antibody to hepatitis B core antigen (HBcAb) could also be used in this manner. Using a microparticle-capture enzyme immunoassay (IMx), a standard curve of fluorescence rate vs HBeAg concentration was constructed to provide quantitative results. The IgM HBcAb index was also measured using a microparticle enzyme immunoassay and serum HBV DNA was measured by a solution hybridization assay. We studied 48 patients who were initially positive for HBeAg and HBV DNA and who were treated with IFN-alpha2b. Their sera were serially evaluated for HBeAg concentration, and results were compared with HBV DNA levels. In the 14 patients who responded to IFN, similar disappearance curves were observed with good intraindividual correlation between the levels of the two markers. In the 34 non-responders, HBeAg levels decreased during treatment but never became negative; HBV DNA levels also decreased during treatment and became transiently undetectable in six patients, falsely suggesting treatment success. The IgM HBcAb index paralleled changes in alanine aminotransferase (ALT) concentration and did not provide additional information. Multiple logistic regression indicated that baseline ALT and HBeAg concentrations were independent predictors of the response to treatment and the addition of neither HBV DNA nor IgM HBcAb improved the model. We conclude that quantitative measurement of HBeAg provides information similar to that of HBV DNA in monitoring and predicting the response to treatment; this technique could be readily adaptable to clinical laboratories. 相似文献
62.
Modulator integrated DFB lasers with more than 600-km transmission capability at 2.5 Gb/s 总被引:2,自引:0,他引:2
M. Ishizaka M. Yamaguchi Y. Sakata Y. Inomoto J. Shimizu K. Komatsu 《Photonics Technology Letters, IEEE》1997,9(10):1406-1408
The modulator integrated DFB laser diodes with more than 600-km transmission capability over normal fiber at 2.5 Gb/s, have been reproducibly achieved. The longest transmission length obtained in the experiment is as long as 800 km. 相似文献
63.
Hayao Imamura Takayuki Nuruyu Tatsuya Kawasaki Toshihiro Teranishi Yoshihisa Sakata 《Catalysis Letters》2004,96(3-4):185-187
For the liquid-phase partial hydrogenation of benzene at 483 K, the selectivity toward cyclohexene was greatly improved upon treating rare earth nitride with ammonia. For YbN obtained by thermal decomposition of Yb(NH2)2 at 1173 K, the selectivity of the NH3-treated YbN was 75%, in contrast to nil for the untreated YbN. 相似文献
64.
SI Watanabe KI Sakasegawa Y Nakamura K Kariatsumari S Suehiro S Shimokawa R Sakata 《Canadian Metallurgical Quarterly》2003,51(4):231-234
In this paper, we report on a new technique of Dumon stent placement using a flexible bronchofiberscope. This procedure was used to insert Dumon stents in two bronchial obstruction and two bronchofistula cases. The stenting technique described here can be used through either a tracheostoma or the oral cavity; it presents a very straightforward and safe procedure that does not require the use of a rigid bronchoscope. 相似文献
65.
The partial realization problem for 2D discrete linear shift-invariant systems is discussed. The authors attempt to establish a reasonable definition of minimality and propose a method for finding the degree and the system function of a minimal realization of a 2D linear system characterized by a given 2D impulse response array. The method used is based on the 2D Berlekamp-Massey algorithm which has a close connection with the 2D Hankel matrix derived from the 2D array. While it compares in efficiency with other methods for identification and approximation of 2D linear systems, it gives a novel approach to the problem in the sense that one does not need any knowledge or assumptions concerning the system degree 相似文献
66.
M. Sakata S. Wakabayashi M. Ikeda H. Goto M. Takeuchi T. Yada 《Microsystem Technologies》1995,2(1):26-31
Novel PZT thin film actuators for optical applications were proposed. Key issues for realizing the actuators such as PZT thin
film processes, mechanical properties evaluation of thin films, and design for laminated structure were described. [1 1 1]-oriented
PZT films were obtained by anneal/non-anneal sputtering process. Also for PZT dry etching, it was made clear low pressure
and low temperature conditions were advantageous for high selectivity and etch rate. ECR etcher was used and etch rate of
1000 A/min and selectivity of 0.56 to photoresist mask were obtained. Young’s modulus and built-in stress of PZT film, measured
by load-deflection method, were 72 GPa, −335 MPa respectively. Using these results, calculated deflection of each actuator
was on the order of a few microns to 20 microns. It was confirmed that deflection of actuators would be enough for the application. 相似文献
67.
K Sato YH Guo J Feng S Sugiyama M Ichinomiya Y Tsukamasa Y Minegishi A Sakata K Komiya Y Yamasaki Y Nakamura K Ohtsuki M Kawabata 《Canadian Metallurgical Quarterly》1998,811(1-2):69-76
Goldfish were classically conditioned to a mixture of two pulse trains differing in both repetition rate and the spectral profile of the pulses. Animals were then tested for generalization to single pulse trains having one or the other spectral profile presented at a variety of repetition rates. Generalization functions of repetition rate were qualitatively similar to those obtained following conditioning to either of the pulse trains alone. Thus, the spectral profile of each pulse type was appropriately associated with the repetition rate at which that pulse type was presented during conditioning. These results indicate that the two concurrent pulse trains making up the conditioning stimuli were analyzed independently, forming two auditory streams. When either of the two pulse trains were presented with a 500 ms onset asynchrony, stream segregation was enhanced. These and other results suggest that many fundamental features of the human sense of hearing are widely shared among vertebrate animals, and may have developed first among fishes. 相似文献
68.
Glass tubes were fractured by internal pressure under atmospheric or superimposed hydrostatic pressure. It is found that the crack length at bifurcation is significantly increased by superimposed hydrostatic pressures. The dynamic energy release rate for a crack propagating with superimposed hydrostatic pressure is calculated. It is shown that the pressure effect on crack length at bifurcation may be explained by combining the energy balance condition and the Yoffe's concept for crack bifurcation. 相似文献
69.
The precise inherent Raman gain shape of several types of dispersion-flattened fibre span was evaluated under different operating conditions in backward pumping. It was found that the overall gain shape greatly depends on the fibre span configuration rather than the operating condition in any fibre span configurations. 相似文献
70.