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991.
Y Miwa M Negishi R Hanaoka Y Hatano H Iwabuchi H Kanemitu S Kaga M Hashimoto T Kasama H Ide E Shimada K Tadokoro 《Canadian Metallurgical Quarterly》1998,38(5):735-740
Recurrent respiratory papillomatosis (RRP), usually confined to the nasopharynx, trachea, and larynx, occasionally can progress to extensive bronchopulmonary disease. Most cases of bronchopulmonary and laryngeal papillomatosis are cytologically benign and do not undergo malignant transformation; however, squamous cell carcinoma (SCC) can arise in RRP in the absence of known risk factors such as radiation and smoking. In this study, the authors investigated molecular genetic alterations occurring in a case of metastasizing SCC that arose in long-standing bronchopulmonary papillomatosis. Genomic DNA from tracheal papillomata, tracheobronchial papillomata, SCC of the lung, and a lymph node metastasis was extracted. The physical state of the human papillomavirus type 11 (HPV-11) DNA was investigated by two-dimensional gel electrophoresis. Molecular genetic alterations of the host genome were studied by direct sequencing of polymerase chain reaction-amplified gene fragments and restriction fragment length polymorphism (RFLP) analysis. Episomal and integrated forms of HPV-11 sequences were detected in histologically benign tumors, but only the integrated form of the viral DNA could be found in malignant tissue samples. Molecular genetic studies revealed that an allelic loss of the interferon-beta gene (IFNbeta-1) and an endogenous type of mutation of the p53 antioncogene were found only in the malignant lesions. Mutations were not observed in the ras, neu, or multiple tumor suppressor (MTS1/p16) genes in any specimens. The authors' data indicated that the p53 genetic mutation was associated with integration of HPV-11 in histologically malignant lesions. This association may promote a progressive genetic instability that can lead to the development and clonal expansion of malignant lesions in RRP. 相似文献
992.
K Chayama Y Suzuki M Kobayashi M Kobayashi A Tsubota M Hashimoto Y Miyano H Koike M Kobayashi I Koida Y Arase S Saitoh N Murashima K Ikeda H Kumada 《Canadian Metallurgical Quarterly》1998,27(6):1711-1716
Treatment of hepatitis B virus (HBV) with lamivudine is effective in suppressing virus replication and results in reduced inflammatory activity. However, the emergence of lamivudine-resistant mutant virus, with amino acid substitution in the YMDD motif of DNA polymerase, has been reported. We report the emergence and takeover of YMDD mutant and re-takeover by wild type during and after long-term lamivudine therapy. YMDD mutants were detected in five patients who showed DNA breakthrough (HBV DNA becoming detectable after a period of DNA negativity), which occurred after 9 to 14 months of lamivudine therapy. Four of five mutants had amino acid sequence YIDD, and the remaining mutant had YVDD. Patients with high HBV-DNA titer and/or hepatitis B e antigen tended to develop breakthrough (P = .038). Using a sensitive and specific polymerase chain reaction (PCR)-based method developed in this study, the emergence of YMDD mutants was detected 1 to 4 months before DNA breakthrough, but not detected in any of the pretreatment sera. The mutants were predominant at breakthrough, but were replaced by wild-type virus 3 to 4 months after cessation of therapy in the two patients who discontinued therapy. One of these patients had a relapse of hepatitis. Mutant continued to replicate in the remaining three patients who continued to receive treatment, and relapse occurred in only one of these patients. Our results suggest that the replication of YMDD mutant viruses is less than wild type and is re-overtaken by wild type after cessation of therapy. Re-administration of lamivudine, possibly combined with other antiviral therapy, might be useful in some patients experiencing hepatitis with lamivudine-resistant variants. 相似文献
993.
Mori J. Nagamatsu M. Hirano M. Tanaka S. Noda M. Toyoshima Y. Hashimoto K. Hayashida H. Maeguchi K. 《Solid-State Circuits, IEEE Journal of》1991,26(4):600-606
A 54 b×54 b multiplier fabricated in a double-metal 0.5 μm CMOS technology is described. The 54 b×54 b full array is adopted to complete multiplication within one latency. A 10 ns multiplication time is achieved by optimizing both the propagation time of the part consisting of 4-2 compressors and the propagation time of the final adder part. The n-channel pass-transistor circuit and the p-channel load circuit are used at the critical blocks to improve the multiplication speed. This multiplier is intended to be applied to double-precision floating-point data processing based on the IEEE standard up to clock range of 100 MHz 相似文献
994.
Y Ishigaki K Yasuda N Hashimoto H Nikaido O Nikaido JI Hayakawa 《Canadian Metallurgical Quarterly》1998,43(5):493-494
We introduced two mutant genes (beige; bg that induces the deficiency of natural killer (NK) activity and xid that decreases the production of immunoglobulin) into KSN nude mice with high reproductive performances. We produced KSN bg/bg(nu/nu) (KSN-bg), KSN-xid/xid(nu/nn) (KSN-xid), KSN xid/xid,bg/bg(nu/nu) (KSN-BNX) and KSN-nu/+ (KS) mice by back-cross (cross-intercross method). All strains showed as high a reproductivity rate as the parental KSN mice. KSN-xid and KSN-BNX mice had a reduced percentage of B220 positive cells in the spleens compared to KSN and KSN-bg mice, but they showed increased percentages of Thy-1 and asialo GM1 positive cells. The serum immunoglobulin concentrations of KSN-BNX were as low as KSN-xid. Both KSN-bg and KSN-BNX mice showed deficient NK activity in spleens, whereas KSN-xid mice showed an elevated NK activity. Compared to nude mice, the growth of both human tumor cell TCO-1 and BxPc-3 transplanted subcutaneously was enhanced in KSN-BNX mice. However Panc-1 cells that was rejected in nude mice was not accepted in KSN-BNX mice. Liver metastasis of human pancreatic tumor cells; Capan-1, BxPc-3 and MIAPaCa-2 were studied. No significant difference was observed in the percentage of metastasis formed mice between nude and KSN-BNX mice. 相似文献
995.
Harutaka Mekaru Shinji Kusumi Noriaki Sato Masami Shimizu Michiru Yamashita Osamu Shimada Tadashi Hattori 《Microsystem Technologies》2007,13(3-4):393-402
LIGA processes have been developed generally in the 2.5D world. We introduced techniques of 3D X-ray lithography and worm
injection molding with a unscrewing release mechanism, and succeeded in the development to three dimensions of LIGA process.
We called this technology 3D-LIGA process, and came to be able to fabricate the plastic molded product with a spiral microstructure.
Furthermore, we succeeded in the trial production of a spiral microcoil using 3D-LIGA process and metallization technique
combining flat and smooth electroplating with a leveling agent and an isotropic chemical etching. The diameter of this microcoil
was 0.5 mm and the length was 1 mm. The width of the Cu coil line was 10 μm, and the pitch was 20 μm. Moreover, we measured
characteristics of this microcoil as an inductor. The inductance and the quality factor at the frequency of 1 GHz were 91 nH
and 5.8, respectively. This is the first time successful fabrication of an electric device with a 3D form like a spiral microcoil
using the 3D-LIGA process has been achieved. 相似文献
996.
Hybrid Design Methodology and Cost-Effectiveness Evaluation of AGV Transportation Systems 总被引:1,自引:0,他引:1
Hoshino S.. Ota J.. Shinozaki A.. Hashimoto H.. 《Automation Science and Engineering, IEEE Transactions on》2007,4(3):360-372
In this paper, we analyze and compare the performance of the vertical and the horizontal automated-guided-vehicle transportation systems. We use results in queuing network theory and a transportation simulator to design a hybrid strategy for this study, and to set the appropriate number of agents in the systems. Next, these two transportation systems are evaluated based on cost-effectiveness criteria. For this purpose, the total construction costs of the systems for the various transportation demands are compared. Finally, we provide analytical results to evaluate and to obtain the most efficient system, based on the validity of each system, under different demand scenario. Note to Practitioners-A good design methodology is essential for the study of the optimal layout in an automated container terminal. Port designers need to select the most efficient automated-guided-vehicle (AGV) transportation system, and to set the appropriate number of agents operating in the system. This study presents a hybrid design methodology and a cost-effectiveness comparison of the vertical and the horizontal transportation systems. Our proposed design methodology is able to derive the combinatorial optimal design solutions rapidly, and at the same time pin point the bottleneck in the system. This proposed methodology can be easily applied to any transportation or logistics system, provided the system can be divided into components represented as nodes in a graph. Our results demonstrate that the horizontal AGV transportation system is more effective than the vertical AGV transportation system under most demand scenarios. 相似文献
997.
Harutaka Mekaru Osamu Nakamura Osamu Maruyama Ryutaro Maeda Tadashi Hattori 《Microsystem Technologies》2007,13(3-4):385-391
We succeeded to transfer a precise micro-pattern combining with an ultrasonic vibration in an atmospheric hot embossing on
the almost same condition as a vacuum hot embossing. This paper reports the effect of the ultrasonic vibration that was verified
experimentally. In the conventional method, a metallic mold and a plastic sheet are heated more than the glass transition
temperature of the plastic, and the softened plastic is flowed into the pattern only by applying a load. On the other hand,
a longitudinal ultrasonic vibration is added in the molding process of an ultrasonic-vibration hot embossing. The synergy
effect of the load and the ultrasonic vibration enables flowing of the plastic into a more precise pattern of the metallic
mold. The longitudinal wave generated by an ultrasonic vibration system of the frequency 15 kHz and output 900 W. A pattern
of the Ni mold used in the experiment was a pyramid hole in which a peak was cut and sidewalls were rounded. Entrance lengths
of pyramids were from 100 to 530 μm and its all of the depth were 260 μm. A polycarbonate was chosen with a replication material.
Compared with the condition that the ultrasonic vibration was not used, a contact force and a contact time could be reduced
to about 1/3 and 1/12, respectively. 相似文献
998.
Hiromu Hashimoto Yasuhiro Ibi Shigeyoshi Kiribe Chihiro Kondou 《Microsystem Technologies》2007,13(8-10):965-971
This paper describes the theoretical modeling for the prediction of slippage onset condition between the paper web and steel roller with experimental verifications. For the first step of modeling, the occurrence of slippage is observed for the cases of uncoated paper (newsprint) and coated paper, and the relation between the slip ratio and roller velocity is measured by changing web tension. Two kinds of theoretical model are proposed, and the applicability of the models is confirmed experimentally. 相似文献
999.
W. A. MacDonald M. K. Looney D. MacKerron R. Eveson R. Adam K. Hashimoto K. Rakos 《Journal of the Society for Information Display》2007,15(12):1075-1083
Abstract— Recent advances in both organic‐ and inorganic‐based electronics processed on flexible substrates offer substantial rewards in terms of being able to develop displays that are thinner, lighter, robust, and conformable, and can be rolled away when not required. In addition, plastic‐based substrates coupled with the recent developments in solution deposition and ink‐jet printing for laying down OLED materials and active‐matrix thin‐film‐transistor (TFT) arrays open up the possibility of cost‐effective processing in high volumes using roll to roll (R2R) processing. To replace glass, however, a plastic substrate needs to be able to offer some or all of the properties of glass, i.e., clarity, dimensional stability, thermal stability, barrier, solvent resistance, and low coefficient of thermal expansion (CTE) coupled with a smooth surface. In addition, a conductive layer may be required. No plastic film offers all these properties so any plastic‐based substrate will almost certainly be a multilayer composite structure. This paper will discuss the issues associated with selecting plastic materials, contrast the various options, and highlight how to gain optimum performance through process control. This will be illustrated with examples of film in use in flexible electronic applications. 相似文献