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101.
Differential scanning calorimetry (DSC) behaviours of glassy As2Se3 containing Ag up to 5 at % were measured at various heating rates. The effect of addition of Ag on crystallization of glassy As2Se3 was investigated. The glass transition temperature decreased with increasing Ag content. Crystallization kinetics were analysed on the basis of the two-step process model, where crystal growth takes place after nucleation. For non-doped As2Se3 two-dimensional growth of crystal was predominant, while for Ag-doped ones three-dimensional growth was very likely. It was supposed for all glassy Ag-doped samples that crystal nuclei exist, though micro-crystallites were not observed on X-ray diffraction traces. The activation energy for crystallization and the glass-forming tendency decreased by the addition of Ag.  相似文献   
102.
Recently, we have shown that an EGF-R-mutant lacking the autophosphorylation sites phosphorylates Shc and retains mitogenic activity. In this report, we have shown that in these cells, in response to EGF, Ras is fully activated with formation of the tyrosine-phosphorylated Shc-Grb2-mSOS complex without the receptor. This pointed out the importance of Shc in EGF-induced Ras activation. To investigate the mechanism of tyrosine phosphorylation of Shc by EGF-R, we carried out in vitro kinase assays using immunoprecipitated EGF-R and bacterially-expressed Shc proteins as substrates. The EGF-R phosphorylated Shc, but not the Shc SH2 mutant, lacking binding ability for phosphotyrosine. This suggests that intact Shc SH2 is essential for the full-length Shc to become phosphorylated, probably by inducing a conformational change in Shc. Thus a Shc SH2 peptide may inhibit competitively Shc phosphorylation. We microinjected the Shc SH2 domain into NIH3T3 cells overexpressing the EGF-R. Microinjected Shc SH2 greatly suppressed EGF-induced DNA synthesis. But microinjection of neither the Shc SH2 mutant nor PLC-gamma 1 SH2 had any effect. This suppressing effect was rescued by comicroinjection of the full-length Shc, suggesting Shc SH2 specifically suppressed the Shc pathway. Thus we concluded Shc phosphorylation is crucial, whereas receptor autophosphorylation is dispensable, in EGF-induced mitogenesis.  相似文献   
103.
In attempt to develop a new chemotherapeutic regimen including carboplatin (CBDCA), epirubicin (EPI), and VP-16 in extensive small cell lung cancer, with a higher dose intensity compared with previous experience of our group, we determined the maximum tolerated dose (MTD) of VP-16 when administered in association with CBDCA (300 mg/ m2, i.v., day 1) and EPI (75 mg/m2, i.v., day 1), recycling chemotherapy every 3 weeks, with the support of granulocyte-colony-stimulating factor (G-CSF). A total of 15 patients received three dose levels of VP-16 (mg/m2, i.v., daily on days 1-3): 100 (three patients), 120 (six), and 140 (six). G-CSF was administered subcutaneously at the dose of 5 micrograms/kg/day on days 6-15 of each chemotherapy course. The MTD was established at 140 mg/m2 and myelotoxicity, grade 4 neutropenia with death for sepsis in one case and grade 3 thrombocytopenia in three cases, was dose limiting. The recommended dose of VP-16 for a phase II study is 140 mg/m2.  相似文献   
104.
Transformation of chick embryonic fibroblasts with Rous sarcoma virus strongly suppresses N-cadherin-mediated cell-cell adhesion, without inhibiting its expression. This suppression is correlated with tyrosine phosphorylation of N-cadherin and catenins, the cadherin-associated proteins, which are known to regulate cadherin function. Experiments with non-myristylation and temperature-sensitive mutants of RSV and with herbimycin A, a potent inhibitor of tyrosine kinases, suggest that both the suppression of cell adhesion and tyrosine phosphorylation of catenins are highly transformation-specific.  相似文献   
105.
106.
A new method which combines analytical and numerical solutions is presented for analyzing coupled transport phenomena between multiple regions. The method was applied to simulate heat transfer from hot laminar forced downward convection in a parallel plate duct to external natural convection through a finite section of one wall. Obtained numerical results showed that the longitudinal wall conduction markedly relaxed the thermal interaction between the two convection systems. Experiments were also performed, using conducting walls made of aluminum, stainless steel and granite. Predicted temperature profiles agreed well with the experimental data.  相似文献   
107.
A shape classifier consisting of a rotating cylinder with a row of blades is derived. Each blade works as a conveyor and the granular materials are transported up the inclined cylinder, the particles roll down on the inner wall of the rotating cylinder. Since the non-spherical particles are  相似文献   
108.
109.
Structural development of isotactic polypropylene (iPP) fibers was analyzed in real time through in-situ WAXD/SAXS and fiber temperature measurements during CO2 laser-heated drawing because the CO2 laser irradiation can nearly fix the necking position on the running fiber. The in-situ WAXD/SAXS measurements were carried out with a high time-resolution of 0.4 ms. The as-spun iPP fibers of two different initial structures were laser-heat-drawn to a draw ratio of 6.5. For the drawing of PP fiber containing mesophase structure, diffraction from the oriented mesophase remained until an elapsed time of 1.0 ms, when oriented α-phase crystal started to form. Meanwhile, for the drawing of PP fiber containing both an α-phase and a mesophase structure, fragmented microcrystals were reorganized by orientation-induced crystallization before an elapsed time of 1.0 ms. The long period increased drastically with fragmentation, and decreased with reorganization. The long period was about 16 nm for both drawn fibers.  相似文献   
110.
ABSTRACT

The needs of aluminium joints have grown in recent years. However, as aluminium forms strong oxide layers on the surface in an atmosphere, joining of these materials is difficult. This is why we conceived a new atmosphere solid-phase bonding method that uses high-frequency induction heating and ultrasonic vibration. The effects of ultrasonic vibration and bonding conditions on this new bonding method were investigated. As a result, we were able to confirm the efficacy of ultrasonic waves on bonding. The bonding mechanism of new bonding method was also clear.  相似文献   
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