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911.
Hamada H. Hirano K. Goda N. Abe H. Hasegawa I. Okita Y. Arioka S. Niina T. 《Electronics letters》1994,30(20):1719-1720
The off state current for polysilicon thin-film transistors for pixels in LCDs has been successfully reduced by introducing a polysilicon buffer layer between a polysilicon active layer fabricated by solid-phase-crystallisation (SPC) and a fused quartz substrate. Off-slate current of less than 1 pA under Vgs=-25 V at Vds=3 V was obtained for n-channel single-gate coplanar transistors using the buffer layer (400 Å) 相似文献
912.
T Nakajima K Miwa Y Ohmori T Sakabe M Fujii T Kajitani 《Canadian Metallurgical Quarterly》1996,23(9):1161-1168
A multi-center collaborative study was conducted in curatively resected gastric cancer patients at Stages II and III to compare oral 5-FU (Group A), oral Tegafur (Group B) and i.v. MMC + oral 5-FU (Group C). From May 1982 to April 1985, 1,012 cases were enrolled at 55 institutions. Some 138 (13.8%) were excluded, and 874 were analyzable. In the analysis of background factors, Group B had more cases with tumor of large diameter and advanced Stage. Adverse effects were relatively mild in all groups, and there was no problem in drug tolerance. Five-year survival rate was 67.6%, 62.4% and 68.6% in Groups A, B and C, respectively, reflecting no significant difference among them. It was 85.0%, 83.0% and 81.1% in Stage II and 52.5%, 51.0% and 59.0% in Stage III of Groups A, B and C, respectively. No significant difference was found, but Stage III of Group C showed a slightly higher survival rate. Supportive clinical study will be required to assess the usefulness of MMC as an introduction therapy. We found no difference in efficacy between 5-FU and Tegafur as maintenance therapy. The life-prolongation effect of fluoropyrimidines in comparison with surgery alone should be studied separately. 相似文献
913.
Ohshima S. Nakamura M.S. Baba S. Tomioka T. Miyachi M. Shimomura Y. 《Lightwave Technology, Journal of》1995,13(9):1838-1846
This paper describes frequency control techniques for cold start and channel recognition functions in coherent multichannel local area networks. A Z-cut quartz etalon can be used to stabilize the optical transmitter frequencies. The capture range and the influence of humidity on a Fabry-Perot etalon are discussed. The frequency deviation of the optical transmitter was estimated to be less than ±1 GHz in the long term. A double AFC loop has been proposed for local LD frequency control. It showed a wide capture range of ±100 GHz. Coherent FDM receiver switching to the desired channel was demonstrated over a range from 0 to 40°C in an experiment 相似文献
914.
OBJECTIVE: To study the correlation of development and survival with amplification of c-erbB2 oncogene in endometrial carcinoma. METHODS: The amplification and expression of c-erbB2 oncogene were determined from formalin-fixed, paraffin-embedded tissues of 25 normal, 31 hyperplastic, and 72 malignant samples of the endometrium in 128 patients, using differential polymerase chain reaction (DPCR) and an immunohistochemical technique. RESULTS: Amplified c-erbB2 (2 to 12 copies) were found in two of 25 (8.0%) normal, 15 of 31 (48.4%) hyperplastic, and 45 of 72 (62.5%) malignant samples. When the results of DPCR were compared with those of the immunohistochemical method, the negative findings concide well with one another, i.e., nonamplification was associated with the absence of immunoreactivity. It was noted that the amplified c-erbB2 was found more significantly in complex and a typical hyperplasias than in simple hyperplasias. The high-level c-erbB2 amplification (at least five copies) was significantly correlated with the histological grade of endometrial carcinoma and vascular or lymphatic invasion. No correlation was seen between c-erbB2 amplification and overall survival in the present group of patients. CONCLUSIONS: The amplified c-erbB2 may play a potential role in the early development of some endometrial carcinomas. The high-level c-erbB2 amplification may identify a subset of aggressive endometrial carcinoma that involves vascular or lymphatic invasiveness and poor cell differentiation playing the role of a marker for clinical prognosis. 相似文献
915.
The extended Ziv-Zakai bound for vector parameters is used to develop a lower bound on the mean square error in estimating the 2-D bearing of a narrowband planewave signal using planar arrays of arbitrary geometry. The bound has a simple closed-form expression that is a function of the signal wavelength, the signal-to-noise ratio (SNR), the number of data snapshots, the number of sensors in the array, and the array configuration. Analysis of the bound suggests that there are several regions of operation, and expressions for the thresholds separating the regions are provided. In the asymptotic region where the number of snapshots and/or SNR are large, estimation errors are small, and the bound approaches the inverse Fisher information. This is the same as the asymptotic performance predicted by the local Cramer-Rao bound for each value of bearing. In the a priori performance region where the number of snapshots or SNR is small, estimation errors are distributed throughout the a priori parameter space and the bound approaches the a priori covariance. In the transition region, both small and large errors occur, and the bound varies smoothly between the two extremes. Simulations of the maximum likelihood estimator (MLE) demonstrate that the bound closely predicts the performance of the MLE in all regions 相似文献
916.
A method is proposed for determining the excitation coefficients of an antenna array operating in a large rectangular waveguide and used as a hyperthermia system. The excitation coefficients of the array elements are optimized for attaining an improved specific absorption rate (SAR) distribution around a deep-seated tumor. The method is applied to a two-dimensional problem of a piecewise homogeneous post in a waveguide representing a section of the human torso. The array is operating below the cutoff frequency of the dominant mode of the waveguide. Numerical simulations have been performed to check the effectiveness of this approach. The results show that by using the proposed optimization method, SAR distributions can be improved 相似文献
917.
The optimization problem corresponding to the design of a presteered broadband processor with maximally flat second-order spatial response in the look direction is discussed. The constraints corresponding to necessary and sufficient conditions for second-order flatness are presented. The nonlinearly constrained optimization approach is unable to consistently locate the global minimum. An approach to solving this problem that essentially converts the nonconvex optimization problem into a parameterized set of convex problems is presented. In the case of 2-D scenarios, the global optimum is determined by finding the roots of a cubic function. The characteristics of the constraints, including the minimum number required and the dependence on the choice of coordinate systems, are examined 相似文献
918.
The stresses and strains in substrate-connector systems in multichip modules (MCMs) are discussed. Simultaneous stresses were applied as structural loads in combined stress models. Modeling results show that definite relations exist between connector pitch, length, substrate thickness and material, and stresses in a connector body 相似文献
919.
The finite element method is applied to stress and strain analyses around rigid spherical particles in elastomers at large extensions. The stress and strain distribution computed agree well with the classical theoretical ones at small strain. At large extension, however, the maximum stress concentration factor increases greatly and the maximum strain concentration factor decreases slightly as strain increases. These tendencies are increased more in carbon black-filled elastomers than in unfilled ones, which can be understood reasonably by considering both the geometric and material non-linearity. Reinforcement of elastomers with rigid spherical particles was also analysed through a numerical computation. The computed results agree with the Guth and Mooney equations at low volume fraction of fillers. In carbon black-filled elastomers, on the other hand, where the modulus is much higher than that given by the above equations, the computations give a good agreement with the experiments, considering the 20% increase in effective diameter of the filler. 相似文献
920.
M Kotani Y Yamamura M Tsudo T Tamatani F Kitamura M Miyasaka 《Canadian Metallurgical Quarterly》1993,84(7):770-775
Rabbits can be infected with human retroviruses such as human T-cell leukemia virus-1 (HTLV-1) and human immunodeficiency virus (HIV), and provide useful animal models to study retroviral diseases such as adult T-cell leukemia and HIV. Previously we have succeeded in generating monoclonal antibodies (mAbs) against rabbit CD4, CD5 and CD11a antigens. To make this animal species more amenable to cellular and molecular studies, we have attempted to extend the panel of mAbs against rabbit CD antigens. Here we report on the generation of three neutralizing mAbs against interleukin-2 receptor alpha chain (IL-2R alpha) (CD25), Kei-alpha 1 (IgG2b), Kei-alpha 2 (IgG2a) and Kei-alpha 3 (IgG1). They specifically recognize the rabbit Mr 55,000 IL-2 binding protein, IL-2R alpha, and completely inhibit both high- and low-affinity IL-2 binding to F648b cells that express IL-2R alpha as well as IL-2R beta. The use of mAb Kei-alpha 1 confirmed that the rabbit IL-2R alpha is not only a low-affinity IL-2R on its own but also an essential component of high-affinity IL-2R as found in other animal species, and that rabbit activated T cells including HTLV-1-transformed cell lines express high levels of the IL-2R alpha. Together with mAbs against various rabbit CD antigens that we reported previously, these neutralizing mAbs to IL-2R alpha will be valuable for studies of human retrovirus infections, such as those induced by HTLV-1 or HIV, in rabbits. 相似文献