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51.
Switching between two cross-coupled lateral modes in gain-guided twin-stripe lasers has been experimentally observed with current injection of nominally identical pulses, which strongly indicates bistability. Near- and far-field patterns at both facets are presented, which clearly shows a skewed light field which couples from under one stripe to under the other. Cross-coupled mode operation was obtained only for relatively long cavity lasers, which is consistent with the theory for twin-stripe lasers with high interstripe gain  相似文献   
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53.
Interaction of a tyrosine kinase type receptor and its ligand induces receptor-dimerization or -oligomerization followed by transphosphorylation and activation of its intrinsic kinase, which leads to a series of intracellular signals. We have previously reported that the membrane-bound form of Steel factor (SLF) induces more persistent tyrosine kinase activation and longer life span of c-kit encoded protein (KIT) than its soluble form (Miyazawa et al, Blood 85:641, 1995). In this study, we used YB5.B8 monoclonal antibody (MoAb) that recognizes the extracellular domain of KIT to investigate whether immobilized anti-KIT MoAb can substitute for SLF as a potent activator of KIT by cross-linking receptors and further compared its effect with each SLF isoform in a factor-dependent cell line M07e. YB5.B8 MoAb in a soluble state suppressed SLF-induced M07e cell proliferation in a dose-dependent manner. By contrast, once this antibody was immobilized on the goat-antimouse MoAb (GAM)-coated culture plates, it supported the growth of M07e cells in the absence of any growth factors, whereas culture the cells in GAM alone or YB5.B8 without GAM-coated plates resulted in rapid cell-death within 24 hours. As with the natural ligand SLF, immobilized YB5.B8 MoAb synergized with granulocyte-macrophage colony-stimulating factor (GM-CSF) in inducing cell proliferation compared with either YB5.B8 MoAb or GM-CSF alone. Immunoblotting with antiphosphotyrosine MoAb showed that interaction of M07e cells with immobilized YB5.B8 induced tyrosine phosphorylation of a series of intracellular proteins including KIT (145 kD). In addition, cross-linking studies using a water-soluble cross linking reagent bis-sulfosuccinimidyl-suberate showed that immobilized YB5.B8 MoAb induced dimerization and activation of KIT. However, as with stimulation by the membrane-bound form of SLF, the kinetics of KIT activation with YB5.B8 MoAb was more prolonged compared with the cells treated with recombinant soluble SLF. Flow cytometry showed that, unlike the cells treated with soluble SLF, no downmodulation of cell-surface KIT expression was observed in M07e cells cultured with immobilzed YB5.B8 MoAb. These data suggest that immobilized antibodies against hematopoietic receptors may replace their ligand-stimulators; however, their activities may resemble the membrane-bound form rather than the soluble form of natural ligands.  相似文献   
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55.
We have previously reported that vitamin K2 (VK2) but not VK1 has a potent apoptosis-inducing effect on freshly isolated leukemia cells from patients with various types of leukemia. By multi-color flow cytometric analysis using monoclonal antibody (mAb), APO2.7, which detects mitochondrial 7A6 antigen specifically expressed by cells undergoing apoptosis, we further investigated the apoptosis-inducing effect of VK2 on minor populations of leukemic blast cells in bone marrow from patients with myelodysplastic syndrome (MDS) and overt myeloid leukemia (post-MDS AML). Limiting dilution of CD95 (anti-Fas) mAb-treated apoptotic Jurkat cells with nonapoptotic CTB-1 cells revealed that APO2.7-positive Jurkat cells were consistently detectable by flow cytometry when present at levels of at least 5% in the CTB-1 suspension. In patient samples the gating area for leukemic clone was determined using cell surface antigen-specific mAbs conjugated with either fluorescein isothionate (FITC) or phycoerythrin (PE) and subsequently the cells stained with phycoerythrin cyanine (PE-Cy5)-conjugated APO2.7 mAb were assessed within the gating area of the leukemic clone for monitoring apoptosis. Treatment of the bone marrow mononuclear cells with 3-10 microM of VK2 (menaquinone-3, -4 and -5) in vitro potently induced apoptosis of the leukemic blast cells as compared with the untreated control cells in all 15 MDS patients tested. This effect was more prominent on blastic cells than that on mature myeloid cells such as CD34-/CD33+ gated cells. In addition, VK2 performed much less effectively on CD3-positive lymphoid cells. In contrast to VK2, VK1 did not show apoptosis-inducing activity. These data suggest that VK2 may be used for treatment of patients with MDS in blastic transformation.  相似文献   
56.
Valuable hybrid systems for hydrogen production by solar energy have been developed and the system efficiency has been estimated and discussed from various points of view. In order to decompose water into hydrogen and oxygen without the consumption of additional reactants, a steady stream of the reacting materials must be maintained in consecutive reaction processes and if the system has a rate determining step extra energy should be supplied to promote the reaction. In the Yokohama Mark 5 Process, the efficiency of the thermoelectric device is as low as 5 %; however, the overall efficiency of hydrogen production can be raised to 20 % by addition of extra electric power.The energetics of a hybrid system combining photochemical, thermochemical and electrochemical reactions have also been discussed.  相似文献   
57.
A finite element formulation for large elasto-plastic deformation of polycrystalline materials is proposed in incremental form. The effect of rotation of crystal axes besides usual element rotaion is taken into account. Some numerical considerations on polycrystalline plasticity (i.e. stress-strain curves for several proportional loadings, effect of change of loading path on stress-strain curve, subsequent yield loci for uniaxial and equi-biaxial loadings and so forth) are given for the case of small deformation by using a plate model which consists of 121 square FCC crystals.  相似文献   
58.
A large-scale solar pond with salty water was constructed in the suburbs of Kitami in 1985. Its performance has been measured and analyzed by the authors after that. The solar pond body is circular of 44 m diameter, and the pond water is of 3 min total depth. After, 15 months, the depth of the salt gradient zone (S.G.Z.) was thinned by 10 cm in the top and by 20 cm in the bottom due to convection of the top and bottom zones. The temperature in the convective storage zone (C.S.Z.) reached 70°C, its maximum, at the beginning of September in 1985, however, it was not as high in 1986 due to contamination of the pond water. The temperature of the storage zone was reduced from November to April due to ice covering on the pond surface. The collected heat yielded largely and the collection efficiency reached more than 30% in summer, but decreased to negative values in winter. The thermal performance of the solar pond was predicted by a simulation calculation, and the calculated result compared well with the measurements.  相似文献   
59.
OBJECTIVES: We performed extracorporeal shock wave lithotripsy (ESWL) as the treatment of first choice on 32 chronic pancreatitis patients with main pancreatic duct (MPD) stones prospectively to establish more convenient and safer treatment. METHODS: All patients were treated in a prone position, and shock waves were discharged from the ventral side. ESWL was performed once or twice a week, and no other treatments before ESWL had been applied. RESULTS: Disintegration of all MPD stones to 3 mm or less in diameter could be achieved in all treated patients. Complete clearance of the stones was obtained in 24 patients (75%) without the necessity of endoscopic extraction of fragments. Reduction of MPD diameters after ESWL was statistically significant (p < 0.01). Epigastric and/or back pain complaints before ESWL were completely alleviated in 79% (periods of follow-up: 16-63 months, mean 44), and the pancreatic exocrine function also improved in 61%. No severe complications occurred in any of the patients. CONCLUSIONS: ESWL, which is comparatively easy to perform, is a safe and efficient approach that changes endoscopy's status as an indispensable pretreatment. Therefore, ESWL can be recommended as the first choice treatment for patients with chronic pancreatitis accompanied by MPD stones that should be tried before consideration of either surgical or endoscopic procedures.  相似文献   
60.
Summary It was found that radical polymerization occurs when the mixture of p-methoxystyrene and styrene in the presence of electron acceptors is photoexcited in basic solvents. Concomitantly, p-methoxystyrenestyrene co-dimers: trans-1-(4-methoxyphenyl)-2-phenyl-cyclobutane and 1-(4-methoxyphenyl)-1,2,3,4-tetrahydronaphthalene are produced. From the results of some polymerization runs and the co-dimer structure, it is considered that the linear co-dimer cation radical is the common precursor for both radical polymerization and cationic dimerization, and the radical polymerization is initiated by its radical end.  相似文献   
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