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111.
M Yamada-Osaki R Sumazaki M Tsuchida K Koike T Fukushima A Matsui 《Canadian Metallurgical Quarterly》1999,93(2):721-727
The natural course and the clinical significance of hepatitis G virus (HGV) infection were investigated in 106 pediatric patients who received chemotherapy for hematological malignancy or underwent bone marrow transplantation (BMT) using HGV-RNA and antibodies to the HGV-E2 protein (anti-E2). HGV markers were detected in 21 patients (19.8%; HGV-RNA in 19 and anti-E2 in 2). Longitudinal analysis of these HGV-infected patients showed that 1 had anti-E2 before the initial blood transfusion, 14 had persistent viremia, and 6 became clear of circulating HGV-RNA after completion of therapy, although 5 of the 6 HGV-cleared patients never developed anti-E2. Reactivation of HGV infection during chemotherapy was observed in two anti-E2-positive, HGV-RNA-negative patients; the reappearance of the same HGV strain was confirmed by phylogenetic analysis. Among BMT survivors without other known causes of liver dysfunction, HGV-RNA-positive patients had a higher peak serum alanine amino transferase (ALT) value than negative patients. Contrary to previous reports, immunosuppressed patients can apparently recover from HGV infection without detectable anti-E2 and some patients who supposedly recovered from HGV infection can nonetheless suffer exacerbation when subsequently immunosuppressed. 相似文献
112.
Saki Kondo Tsukasa Azeta Yoshiaki Ukita Yuichi Utsumi 《Microsystem Technologies》2010,16(8-9):1577-1580
The use of three-dimensional (3D) microstructures is becoming essential attempt to develop next generations’ microdevices, to integrate many modules and various functions, and enhance the performance of device. In this paper, we present a new concept for lab on a chip using 3D structure and centrifugal pumping for integrated functional fluid systems such as high-throughput screening, and point of care testing systems which has stacked multiple structures with 3D-interconnection. The use of 3D structure brings many benefits for above high throughput systems, such as possibility to integrate various modules enabling to perform total assay operation, from sample preparation for biochemical reaction and their detection on one platform. For this concept, the most important key technology is control of a vertical valving and transportation of liquid between different 2D micro channel networks with different height levels. We demonstrated such vertical liquid transportation in 3D micro channel networks through the high aspect ratio capillary bundle filter by controlling spinning speed of device and centrifugal force as a pumping force, and confirmed capillary bundle could be employed as vertical microvalve for 3D fluidic systems using centrifugal force as a pumping method. 相似文献
113.
Ali Dashti Ahmad Ramazani SA Yuichi Hiraoka Sang Yull Kim Toshiaki Taniike Minoru Terano 《Polymer International》2009,58(1):40-45
BACKGROUND: Kinetic and morphological aspects of slurry propylene polymerization using a MgCl2‐supported Ziegler–Natta catalyst synthesized from a Mg(OEt)2 precursor are investigated in comparison with a ball‐milled Ziegler–Natta catalyst. RESULTS: The two types of catalyst show completely different polymerization profiles: mild activation and long‐standing activity with good replication of the catalyst particles for the Mg(OEt)2‐based catalyst, and rapid activation and deactivation with severe fragmentation of the catalyst particles for the ball‐milled catalyst. The observed differences are discussed in relation to spatial distribution of TiCl4 on the outermost part and inside of the catalyst particles. CONCLUSION: The Mg(OEt)2‐based Ziegler–Natta catalyst is believed to show highly stable polymerization activity and good replication because of the uniform titanium distribution all over the catalyst particles. Copyright © 2008 Society of Chemical Industry 相似文献
114.
Sasaki K. Ishibashi K. Shimohigashi K. Yamanaka T. Moriwake N. Honjo S. Ikeda S. Koike A. Meguro S. Minato O. 《Solid-State Circuits, IEEE Journal of》1990,25(5):1075-1081
A 4-Mb CMOS SRAM having 0.2-μA standby current at a supply voltage of 3 V has been developed. Current-mirror/PMOS cross-coupled cascade sense-amplifier circuits have achieved the fast address access time of 23 ns. A new noise-immune data-latch circuit has attained power-reduction characteristics at a low operating cycle time without access delay. A 0.5-μm CMOS, four-level poly, two-level metal technology with a polysilicon PMOS load memory cell, yielded a small cell area of 17 μm2 and the very small standby current. A quadruple-array, word-decoder architecture allowed a small chip area of 122 mm2 相似文献
115.
Kimiyuki Mitsui Makoto Koike Hidehiko Tsukamoto Minoru Yajima 《Precision Engineering》1997,20(2):93-98
Conventional ultrasonic displacement-measuring systems normally employ the pulse-echo technique. Resultant resolution capability, however, typically is not suitable for meeting high-dimensional, in-process measurement standards used in cutting and grinding operations. This paper presents a new ultrasonic sensor for displacement measurement based on astigmatic focus error detection. The measuring principle and basic analysis applied in the design method are described in detail, after which the validity of the principle is demonstrated by the results of experimental evaluations. 相似文献
116.
Yuichi Tamura 《Corrosion Science》2009,51(7):1560-223
Effect of surface oxide on Pt-Co alloy electrodes on the oxygen reduction reaction (ORR) was investigated in 0.5 M sulfuric acid solution by electrochemistry, ellipsometry, laser Raman scattering spectroscopy, and XPS. The oxide as thick as 1-2 nm increases the overpotential of ORR and falls down efficiency of PEFC. The thickness of the oxide films is precisely determined by ellipsometry. The oxide film 1.9 nm thick was formed on Pt-50 mol% Co electrode by constant potential oxidation at 1.20 V and the film 1.5 nm thick remains on the electrode at 0.6 V at which ORR already starts. The remaining oxide decreases the current density of ORR and increases the overpotential. On pure Pt electrode, the similar influence of the oxide film was observed. 相似文献
117.
T Fujimatsu M Tsunemoto M Shimada Y Ohta S Endo A Ishizawa K Koike M Akagi T Watari J Kobayashi 《Canadian Metallurgical Quarterly》1990,10(1):76-80
This report concerns a 10-month-old infant with subtotal cor triatrium associated with left sided partial anomalous pulmonary venous connection to the innominate vein. In the operation, we found that the fossa ovalis existed between the right atrium and the accessory atrial chamber. We performed a radical operation which consisted of a resection of the intra-left-atrial diaphragma and a anastomosis of the vertical vein to the left atrium. His postoperative course was uneventful, and the result was satisfactory. We have presented and reviewed our case, and then discussed the embryogenesis and the hemodynamics. To our knowledge, our case represents the first successful surgical repair of this combination of defects in Japan. 相似文献
118.
Tetsukuni Oikawa Masaaki Kondo Yoshinobu Mizuno Yuichi Watanabe Hiroshi Fukuoka Ken Muramatsu 《Reliability Engineering & System Safety》1998,62(3):251-271
An integrated code system SECOM-2, developed at the Japan Atomic Energy Research Institute (JAERI), has the following functions for systems reliability analysis in seismic probabilistic safety assessments (PSAs): (1) calculation of component failure probability, (2) extraction of minimal cut sets (MCSs) from a given fault tree (FT), (3) calculation of frequencies of accident sequences and core damage, (4) importance analysis with several measures with consideration of unique parameters of seismic PSAs, (5) sensitivity analysis, and (6) uncertainty analysis. This paper summarizes the special features of SECOM-2 to perform the analyses mentioned above. At JAERI, using an integrated FT which represents seismically induced core damage due to all initiating events as a system model to calculate core damage frequency of a nuclear power plant, SECOM-2 can calculate conditional point estimate probabilities of system failures, losses of safety functions, and core damage as a function of earthquake motions. The point estimate is computed by a method which gives an exact numerical solution using the Boolean arithmetic model method. As for consideration of correlation of component failure, which has been an important issue in seismic PSAs, a new technique based on direct FT quantification by a Monte Carlo simulation is being added to SECOM-2. Adding this technique, the core damage frequency can be calculated not only with the upper bound approximation based on MCSs but also with a near exact solution taking into account the correlation among all components. This paper also presents the preliminary results of a seismic PSA of a generic BWR plant in Japan performed at JAERI to demonstrate the functions of the SECOM-2 code. 相似文献
119.
M Sonoda J Kobayashi M Takezawa T Miyazaki T Nakajima H Shimomura K Koike A Satomi H Ogino R Omoto T Komoda 《Canadian Metallurgical Quarterly》1997,247(2):417-427
The tibialis anterior muscle and soleus muscle of apolipoprotein-E-deficient mice were examined by light and electron microscopy. By light microscopy, sarcoplasmic inclusions were seen in tibialis anterior muscle and 40% of type 2 myofibers were affected in all animals over 8 months of age. These inclusions reacted for nonspecific esterase, cytochrome oxidase, and myoadenylate deaminase and were also periodic acid Schiff positive and stained basophilic with hematoxylin. Moreover, they reacted immunocytochemically with an antibody specific to fragment 17 to 24 of the published sequence of Alzheimer's cerebrovascular amyloid peptide. Immunoreactivity was lost when the antibody was adsorbed with the appropriate synthetic peptide. Ultrastructurally, the inclusions consisted of tubular arrays and were similar to those observed in human muscle in several pathological conditions. In type 1 myofibers of both tibialis anterior and soleus muscle, however, mitochondrial abnormalities including an increase in their number and size were detected, but tubular aggregates were not seen. These large mitochondria possessed an electron-dense inner chamber with an increased number of tightly packed cristae. The results obtained suggest that in these mice there is a disturbed lipid metabolism in skeletal muscle fibers that manifests itself with an accumulation of phospholipid in the form of sarcoplasmic reticulum tubules in the type 2 fibers and enlarged mitochondria with tightly packed cristae in the type 1 fibers. In addition, beta-amyloid protein was closely associated with the accumulated tubules and vesicles of sarcoplasmic reticulum and may represent dysregulation of amyloid precursor protein metabolism. 相似文献
120.
Y Uesugi K Toba K Nikkuni I Fuse T Koike A Shibata 《Canadian Metallurgical Quarterly》1995,36(10):1210-1216
Leukemic transformation in essential thrombocythemia (ET) is rare. We describe a patient with ET which transformed to megakaryoblastic leukemia with myelofibrosis after treatment with melphalan for 8 years. His course after transformation smouldered for 20 months without antileukemic chemotherapy. A 61-year-old man was referred by a local doctor to Niigata University Hospital due to nasal bleeding in June 1984. Complete blood count (CBC) was as follows; hemoglobin 12.4 g/dl, platelets 268.8 x 10(4)/microliters, and white blood cells 11,900/microliters, with differentials of 39% PMN, 1% basophils, 2% eosinophils, 4% monocytes, and 13% lymphocytes. Bone marrow examination revealed hyperplasia of megakaryocytes without increase of reticulin fibers. Neutrophil alkaline phosphatase activity and karyotype of marrow cells were normal. ET was diagnosed. He was followed up by local doctor. The platelet count was controlled at a level of approximately 40 x 10(4)/microliters with melphalan for eight years. In January 1992 he developed pain in his lower extremities. He was admitted to our hospital on May 29, 1992. CBC was as follows; hemoglobin 8.9 g/dl, platelets 14.3 x 10(4)/microliters, and white blood cells 3,500/microliters, with differentials of 25% PMN, 5% monocytes, 28% lymphocytes, and 24% blasts. Bone marrow aspiration was unsuccessful and bone marrow biopsy revealed increases in fibroblasts and collagen fibers. Circulating blasts were positive for CD4, CD7, CD25, CD13, CD33, CD34, and HLA-DR and partly positive for CD41 and CD36. In ultrastructural cytochemistry blasts were positive for platelet peroxidase but negative for myeloperoxidase. Cytogenetic study revealed 46, XY, +der (1) t(1:7) (p11;q11) in all of five metaphases. He was diagnosed with megakaryoblastic leukemia accompanied by myelofibrosis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献