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991.
T Yamakawa H Nagoshi A Takahashi R Fukumura S Takahashi M Nomura H Isobe K Ide T Ayabe S Shimizu 《Canadian Metallurgical Quarterly》1995,36(10):1175-1181
A 55-year-old patient with multiple myeloma (IgG-lambda) diagnosed in November 1988 was admitted because of bone pain throughout the body. After plasmapheresis and several courses of chemotherapy, a massive tumor of the left thoracic wall involving the rib appeared. Radiotherapy was performed to ameliorate the severe chest pain, after which myelomatous pleural effusion appeared on the left side. The serum, urine and pleural effusion revealed increased activity of amylase of the salivary type. Amylase activity was also detected in the supernatant of myeloma cells cultured from pleural effusion. We reviewed 12 cases of ectopic amylase-producing multiple myeloma. All the cases except one have been reported from Japan, and hyperamylasemia in these cases was detected at diagnosis or during course of the illness. Moreover, cytogenetic analysis of myeloma cells of previous reports revealed structural abnormalities including chromosome 1, near the amylase gene locus. This case also showed t (1; 10) (q 21?; q 26) by examination of 8 metaphase derived from bone marrow. These observations suggested that ectopic amylase production was induced by irradiation to the plasmacytoma of thoracic wall. 相似文献
992.
A procedure to expand plant capacities over a time horizon is presented under multiobjectives. A stepwise interactive approach has been proposed to formulate a problem that is small but complete enough to provide a best-compromise solution for decision-making. The approach relies on the relaxation of flexible constraints and the sensitivity analysis of linear programming. It yields the significant feature of identifying the expansion increments associated with specific objectives or with structural infeasibility. The resulting multiobjective mixed-integer linear programming problem was solved advantageously by an interactive goal programming algorithm. An illustrative example is provided to clarify the procedure and show its computational effectiveness. 相似文献
993.
994.
Masanori Onozuka Yasushi Oda Kingo Azuma Kouji Satake Satoshi Kasai Kouichi Hasegawa 《Fusion Engineering and Design》1995,30(4):373-383
A railgun pellet injection system has been developed for fusion experimental devices. Using a low electric energy railgun system, hydrogen pellet acceleration tests have been conducted to investigate the application of the electromagnetic railgun system for high speed pellet injection into fusion plasmas. In the system, the pellet is pre-accelerated before railgun acceleration. A laser beam is used to induce plasma armature. The ignited plasma armature is accelerated by an electromagnetic force that accelerates the pellet. Under the same operational conditions, the energy conversion coefficient for the dummy pellets was around 0.4%, while that for the hydrogen pellets was around 0.12%. The highest hydrogen pellet velocity was 1.4 km s−1 using a 1 m long railgun. Based on the findings, it is estimated that the hydrogen pellet has the potential to be accelerated to 5 km s−1 using a 3 m long railgun. 相似文献
995.
Toba H. Inoue K. Shibata K. Nosu K. Iwatsuki K. Takato N. Shimizu M. 《Electronics letters》1989,25(14):885-887
A 16-channel optical FDM distribution/transmission experiment at around 1534 nm wavelength is demonstrated utilising an Er/sup 3+/-doped fibre amplifier. 16 intensity-modulated optical signals at 622 Mbit/s were amplified simultaneously at a gain of 15.2-18.5 dB. One of the amplified signals is selected using the waveguide frequency selection switch and directly detected with a receiver sensitivity of -38 dBm (P/sub e/=10/sup -9/).<> 相似文献
996.
Shimizu Y. Iyotani R. Konishi N. Yatsuo T. 《Electron Devices, IEEE Transactions on》1989,36(5):1001-1004
A high-voltage self-protected thyristor with a well structure formed in its p-base layer whose operation is based on avalanche breakdown is described. The device structure is simple and easy to fabricate compared to other avalanche-type devices. Numerical analyses and experiments demonstrate that the breakover voltage can be controlled by varying the well diameter and/or its depth. The breakdown voltage fluctuation of the device is 10% when the junction temperature is varied from 23 to 100°C. The device is turned on safely at 7300 V 相似文献
997.
998.
PURPOSE: To clarify the role of the vitreous in idiopathic macular hole formation. METHODS: We prospectively evaluated the vitreous before and during vitreous surgery in 64 consecutive eyes of 62 patients (stage 1B, four eyes; stage 2, ten eyes; stage 3, 43 eyes; stage 4, four eyes) with macular holes; another three eyes underwent a second vitrectomy. After core vitrectomy, the premacular vitreous cortex was examined by applying gentle suction. The detached posterior hyaloid face was observed under endoilluminiation. RESULTS: We observed in all eyes a liquefied lacuna anterior to the posterior fundus before and during vitreous surgery. The premacular vitreous cortex was extremely thin and elastic upon gentle suction. A premacular ring, the diameter two to four times that of the Weiss ring, was observed in 48 of 57 eyes (84%) with stages 1B, 2, and 3 macular hole. In most cases, the vitreous cortex within the premacular ring either was absent or had a break, resulting in a premacular round defect. The vitreous cortex peripheral to the premacular ring, which was thick and less deformed, never showed a break. In eyes that had undergone a second vitrectomy, we noted residual cortex or an epiretinal membrane around the macular hole. CONCLUSIONS: The premacular vitreous cortex is extremely thin and elastic. It is sharply demarcated by a ring from the thick peripheral vitreous cortex. Tangential traction, which causes macular holes, appears to originate exclusively in the premacular vitreous cortex that forms the posterior wall of the premacular liquefied pocket. 相似文献
999.
KR Chen S Shimizu S Miyakawa A Ishiko H Shimizu T Hashimoto 《Canadian Metallurgical Quarterly》1996,134(2):340-346
The CO dehydrogenase enzyme complex from Methanosarcina thermophila contains a corrinoid/iron-sulfur enzyme composed of two subunits (delta and gamma). The cdhD and cdhE genes, which encode the delta and gamma subunits, respectively, were cloned and sequenced. The cdhD gene is upstream of and separated by 3 bp from cdhE. Both genes are preceded by apparent ribosome-binding sites. Northern (RNA) blot and primer extension analyses indicated that cdhD and cdhE are cotranscribed from a promoter located several kilobases upstream of cdhD. The putative CdhD and CdhE sequences are 37% identical to the sequences deduced from the genes encoding the beta and alpha subunits of the corrinoid/iron-sulfur enzyme from Clostridium thermoaceticum. The CdhE sequence had a four-cysteine motif with the potential to bind a 4Fe-4S cluster previously identified in the corrinoid/iron-sulfur enzyme by electron paramagnetic resonance spectroscopy. A T7 RNA polymerase/promoter system was used to produce CdhD and CdhE independently in Escherichia coli. The purified CdhD protein was reconstituted with hydroxocobalamin in the base-on configuration. The purified CdhE protein exhibited an Fe-S center and base-off cobalamin binding in which the benzimidazole base nitrogen atom was no longer a lower axial ligand to the cobalt atom. 相似文献
1000.
H Yamada A Chiba T Endo A Kobata LV Anderson H Hori H Fukuta-Ohi I Kanazawa KP Campbell T Shimizu K Matsumura 《Canadian Metallurgical Quarterly》1996,66(4):1518-1524
Dystoroglycan is encoded by a single gene and cleaved into two proteins, alpha and beta-dystroglycan, by posttranslational processing. The 120kDa peripheral nerve isoform of alpha-dystroglycan binds laminin-2 comprised of the alpha 2, beta 1, and gamma 1 chains. In congenital muscular dystrophy and dy mice deficient in laminin alpha 2 chain, peripheral myelination is disturbed, suggesting a role for the dystroglycan- laminin interaction in peripheral myelinogenesis. To begin to test this hypothesis, we have characterized the dystroglycan-laminin interaction in peripheral nerve. We demonstrate that (1) alpha-dystroglycan is an extracellular peripheral membrane glycoprotein that links beta-dystroglycan in the Schwann cell outer membrane with laminin-2 in the endoneurial basal lamina, and (2) dystrophin homologues Dp116 and utrophin are cytoskeletal proteins of the Schwann cell cytoplasm. We also present data that suggest a role for glycosylation of alpha-dystroglycan in the interaction with laminin. 相似文献