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31.
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
32.
Ryohei Kimura Akiyoshi Monma Jinsong Duan Mitsuru Uesugi 《Wireless Personal Communications》2006,38(1):27-42
Orthogonal frequency division multiplexing (OFDM) is robust against multi-path interference due to using a lot of low symbol rate sub-carriers. In order to mitigate the degradation due to multi-path interference, guard time interval (GI) is inserted into each OFDM symbol. However, redundant allocation to GI leads to loss of effective transmission power. We propose the Block-OFDM which can reduce the GI overhead ratio per frame compared with conventional OFDM. In Block-OFDM system frequency domain equalization (FDE) is carried out in order to remove multi-path interference. We evaluated Block-OFDM performance in a frequency selective fading channel and compared with that of conventional OFDM.
Ryohei Kimura received his B.E. and M.S degrees in communications engineering form Tohoku University, Sendai, Japan, in 2001 and 2003, respectively. In 2003, he joined Panasonic Mobile Communications Co., Ltd. His current research interests include such mobile communication technologies as OFDM and MIMO (MLD), and the like.
Akiyoshi Monma received his B.E. in communications engineering form Tohoku University, Sendai, Japan, in 1998. In 1998, he joined Panasonic Mobile Communications Sendai R&D Lab. Co., Ltd. His current research interests include such mobile communication technologies as OFDM and PAPR reduction, and the like.
Jinsong Duan received his B.E. and M.S. from Changsha Institute of Technology, China in 1987 and 1990. He received his Ph.D. from Osaka City University, Japan in 2000. From 2000–2003 he was with Mitsubishi Electric Corporation, where he engaged in research and development of WCDMA systems. From 2003, he joined Panasonic Mobile Communications Co., Ltd. His current interests include such mobile communication technologies as OFDM, MIMO, link adaptation, scheduling, and TDMA/FDMA/CDMA systems.
Mitsuru Uesugi received his B.E. degree from Waseda University in 1986 and received his Ph.D degree from Tohoku University in 2004, respectively. He is a general manager in the Mobile Communication Technology Development Center of Panasonic Mobile Communications Co., Ltd. His current research interests include such mobile communication technologies as equalization, interference cancellation, modulation method, and the like. 相似文献
33.
A wide-dynamic-range single-mode optical time-domain reflectometer using a P2O5 highly doped fibre Raman laser and a cooled Ge-PIN photodiode has been realised for the first time. The maximum detectable one-way loss was improved to 35dB in the 1.5 ?m wavelength band. 相似文献
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Ishikawa S Naetoko E Kawamura S Yamaguchi R Higuchi M Kojima T Yamato Y Takahashi M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(2):87-94
We investigated 160 kinds of pesticide residues in 715 samples of 116 kinds of foods distributed in Kitakyushu city. Sixty kinds of pesticides were detected in 55 kinds of foods (204 samples) in the range of 0.002-22 mg/kg. Five kinds of pesticides in 7 samples violated the residue standards and the indication of "unused". The detection ratios of unregulated pesticide in domestic and imported foods were 27.8 and 33.0%, respectively. Iprodione, dicofol, diethofencarb, procymidone and chlorfenapyr (for domestic food) and total bromine, benomyl, chlorpyrifos, dicofol, fenvalerate, cypermethrin and dimethoate (for imported food) showed relatively high detection ratios. Chinese cabbage, garland chrysanthemum, tomatoes and green teas (domestic) and broccoli, bananas, grapefruit, lemons, oranges, frozen edamame and frozen kidney beans (imported) showed high relative pesticide detection ratios. Residual pesticides were detected with relatively high frequency in imported fruits, imported frozen foods and imported processed foods. 相似文献
37.
S Uesugi 《Canadian Metallurgical Quarterly》1995,40(10):1494-1501
38.
Hakoshima Toshio; Toda Shoji; Sugio Shigetoshi; Tomita Ken-ichi; Nishikawa Satoshi; Morioka Hiroshi; Fuchimura Kayoko; Kimura Tsuyoshi; Uesugi Sei-ichi; Ohtsuka Eiko; Ikehara Morio 《Protein engineering, design & selection : PEDS》1988,2(1):55-61
Recognition by ribonuclease T1 of guanine bases via multidentatehydrogen bonding and stacking interactions appears to be mediatedmainly by a short peptide segment formed by one stretch of aheptapeptide, Tyr42-Asn43-Asn44-Tyr45-Gly46-Gly47-Phe48. Thesegment displays a unique folding of the polypeptide chainconsistingof a reverse turn, Asn44-Tyr45-Glu46-Gly47, stabilized by ahydrogen-bond network involving the side chain of Asn44, themain-chain atoms of Asn44, Gly47 and Phe48 and one water molecule.The segment is connected to the C terminus of a ß-strandand expands into a loop region between Asn43 and Ser54. Lowvalues for the crystallographic thermal parameters of the segmentindicate that the structure has a rigidity comparable to thatof a ß-pleated sheet. Replacement of Asn44 with alanineleads to a far lower enzymatic activity and demonstrates thatthe side chain of Asn44 plays a key role in polypeptide foldingin addition to a role in maintaining the segment structure.Substitution of Asn43 by alanine to remove a weak hydrogen bondto the guanine base destabilized the transition state of thecomplex by 6.3 kJ/mol at 37°C. In contrast, mutation ofGlu46 to alanine to remove a strong hydrogen bond to the guaninebase caused a destabilization of the complex by 14.0 kJ/mol.A double-mutant enzyme with substitutions of Asn43 by a histidineand Asn44 by an aspartic acid, to reproduce the natural substitutionsfound in ribonuclease Ms, showed an activity and base specificitysimilar to that of the wild-type ribonuclease Ms. The segmenttherefore appears to be well conserved in several fungal ribonucleases. 相似文献
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