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排序方式: 共有726条查询结果,搜索用时 15 毫秒
81.
T. Ikehata K. Oohashi N. Y. Sato T. Tanabe H. Mase 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1992,70(1-4):26-32
Centrifugal separation of elements has been explored in rapidly rotating metal plasmas. The plasma is produced and driven into rotation by cross-field, vacuum discharge in a coaxial plasma gun. A large separation factor is measured in Cu/Zn plasmas. In particular, a hollow density profile which improves the separative power is found to be established in the plasma column. 相似文献
82.
83.
R Okamoto H Harano T Tamura J Tanabe H Fujita H Fukawa H Kanamori M Matsu?aki S Motomura H Mohri 《Canadian Metallurgical Quarterly》1993,34(8):957-961
A 53-year-old male was admitted to our hospital with abdominal pain. Physical examination revealed marked splenomegaly. The white blood cell count increased to 5.8 x 10(4)/microliters. Bone marrow biopsy showed hypercellularity with a moderate increase in reticulin fiber. Chromosomal analysis showed 47, XY, +9q-, -9q- without Ph1 chromosome and bcr-abl rearrangement. MCNU therapy was successful in reducing the white blood cell count and splenomegaly. It is likely that the diagnosis of our patient is compatible with the neutrophilic myelofibrosis described by Stewart, et al. 相似文献
84.
85.
Operation management is an essential technology for the “OTV (Orbital Transfer Vehicle) Network” which has been proposed as a promising space transportation infrastructure for the next century. In addition to the nominal mode scheduling, the management system must quickly re-make the schedule in the case of failures of some system elements, inputs of urgent missions or mission alterations. This paper analyses this management as a new control problem, and proposes a distributed artificial intelligence-type system architecture to deal with it. The effectiveness of the system has been verified by simulation studies assuming practical problem settings. 相似文献
86.
A new idea for the development of ultra high strength steels by utilizing the spinodal decomposition of the Fe-Mo binary system is proposed. The idea comprises the restraint of the brittleness of the Fe-Mo alloy by reducing the Mo-content necessary to spinodal decomposition and by microstructure refining such as grain refining, subgrain refining etc; the former is realized by the alloying with some elements which, in general, have a tendency towards ordering (i.e., negative interchange energy between the nearest neighbour atoms) when combined with iron, and the latter by thermomechanical treatment and/or cold rolling. On the basis of the idea, that hidden properties indispensable to high strength materials are successfully drawn from the Fe-Mo alloy; we have obtained a 4GPa grade high tensile steel of Fe-Mo-Co-V. This idea is sure to contribute new suggestions to the development of high strength materials. 相似文献
87.
Molecular determinants of calcium-dependent inactivation in cardiac L-type calcium channels 总被引:1,自引:0,他引:1
We investigated the nature and structural requirements for Ca(2+)-dependent inactivation of cardiac L-type Ca2+ channel. Investigation of subunit requirements indicates that the interaction of alpha 1 subunit with ancillary subunits, especially beta subunit, is important for this property. Replacement of the putative cytoplasmic regions of the cardiac alpha 1 subunit with skeletal muscle counterparts eliminates Ca(2+)-dependent inactivation, indicating that the site regulated by Ca2+ resides in the cytoplasmic region of the alpha 1 subunit. Deletion of the carboxy-terminal region of the cardiac alpha 1 subunit does not eliminate this property, suggesting that the modulation by protein kinase A may not be involved in this mechanism. Single amino acid substitution that strongly reduces Ca2+ selectivity of Ca2+ channels also eliminates Ca(2+)-dependent inactivation, suggesting the close link between the ion selectivity and Ca(2+)-dependent inactivation. 相似文献
88.
T Takahashi H Ishikura K Iwai C Takahashi H Kato T Tanabe T Yoshiki 《Canadian Metallurgical Quarterly》1993,36(2):76-82
The permanent pancreas carcinoma cell line, PCI-24, was developed in order to analyse cytokine regulation on pancreas carcinoma and lymphokine-activated killer (LAK) cell interaction. PCI cells expressed ICAM-1 and HLA-ABC, but not HLA-DR antigens. PCI cells showed augmented ICAM-1 and HLA-ABC expression when incubated with interferon gamma (IFN gamma) and tumour necrosis factor alpha. A similar but weak augmentary effect on the HLA-ABC and ICAM-1 surface expression was seen with interleukin-1 beta treatment. Natural attachment of LAK to PCI cells was augmented by recombinant IFN gamma in close association with ICAM-1 up-regulation on PCI cells. In addition, natural attachment was significantly inhibited by anti-LFA-1 and anti-ICAM-1 antibody treatments. Cytotoxicity of the LAK cells against PCI cells was also significantly inhibited with the same treatment. Thus, the attachment of LAK cells to PCI cells through LFA-1/ICAM-1 molecules appeared to be essential for the cytotoxicity for PCI cells. Pretreatment of PCI cells, but not of LAK cells, with IFN gamma or other cytokines resulted in a decrease of susceptibility for LAK cell cytotoxicity. The decreased susceptibility inversely correlated with HLA-ABC expression on the PCI cells. The collective evidence indicates that, although LAK cell attachment to pancreas carcinoma cells through the LFA-1/ICAM-1 molecule is augmented by IFN gamma, IFN gamma treatment of pancreas carcinoma cells reduces LAK cell cytotoxicity possibly through an increase in HLA-ABC or a regulation of molecules closely associated to HLA-ABC expression. 相似文献
89.
90.
The liver microsomes of the Mongolian gerbilMeriones unguiculatus catalyzed the hydroxylation of various saturated fatty acids (C8−C18), alcohols (C12 and C16) and hydrocarbon (C12) to the corresponding ω- and (ω-1)-hydroxy derivatives. Lauric acid was hydroxylated most effectively among saturated fatty
acids and the order of activity as hydroxylation substrates was C12>C14>C13>C16>C10>C18>C8. The specific activity of laurate hydroxylation (5.99 nmol/mg microsomal protein/min) in gerbil liver microsomes was higher
than that observed in other species. 1-Dodecanol was also hydroxylated very effectively (4.58 nmol/mg microsomal protein/min)
by gerbil liver microsomes, but in general the hydroxylation rates for fatty alcohols were much lower than those for the corresponding
acids. It was found from both inhibitor and cofactor studies that the enzyme catalyzing the hydroxylation of fatty acids and
alcohols in the liver microsomes of the Mongolian gerbil was a typical cytochrome P-450-linked monooxygenase, and at least
two different cytochrome P-450 species were involved in the hydroxylation.
Presented in part at the AOCS annual meeting (a joint meeting with the Japan Oil Chemists' Society), Honolulu, Hawaii, May
1986. 相似文献