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991.
J Taki K Nakajima I Matsunari H Bunko S Takata M Kawasuji N Tonami 《Canadian Metallurgical Quarterly》1997,38(10):1503-1510
We investigated the effect of bioflavonoid quercetin on tyrosine phosphorylation and phospholipase D (PLD, EC 3.1.4.4) activation in rabbit peritoneal neutrophils stimulated by N-formylmethionyl-leucyl-phenylalanine (fMLP). The quercetin dose-dependently inhibited degranulation and superoxide production in fMLP-stimulated neutrophils. A strong inhibitory effect of quercetin on the tyrosine phosphorylation of several proteins (40, 42, 43, 45, 46 and 75 kDa) was observed when the neutrophils were pretreated with different concentrations of quercetin. Furthermore, quercetin inhibited mitogen activated protein kinase (MAP kinase) and PLD activation induced by fMLP in a dose-dependent manner. The reduction in PLD activity was 30% at 0.1 microM and 70% at 100 microM of quercetin. These results suggest that impairment of neutrophil functions by quercetin may be due, at least in part, to inhibition of tyrosine phosphorylation and PLD activation. 相似文献
992.
993.
K. N. Anakhaev 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(9):586-592
Conclusion The presently existing methods or calculating seepage in inclined ASEs have a limited area of use and often give substantial deviations from the actual values. At the same time, no analytical relations are known for calculating Iex in the backwater zone of the LP. The formulas proposed in the article permit determining all main parameters of the seepage flow, including separately for the zones of effluent seepage and backwater of the LP, with an accuracy sufficient for engineering calculations.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 9, pp. 33–36, September, 1992. 相似文献
994.
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 1, pp. 14–15, January, 1992. 相似文献
995.
The paper compares experimental and calculated pulse shapes and spectra of signals for bidirectional right transducers with radically different protectors, namely, those from epoxy glue with a filler and ceramic. The new data support the previously made conclusion (from calculated parameters of emitted pulses) that in protectors from composite materials (with low propagation velocities of longitudinal elastic waves) signal spectra can have several pronounced peaks, and their waveforms can exhibit beats (oscillating amplitude modulation). 相似文献
996.
997.
The paper has described the composition and structural behavior of a free spanning ductile frame system to be used in seismic areas. The inelastic performance, ductility, and redundancy of the system is compared with a conventional ductile moment resisting frame. It is shown that the structural performance of the system is equal or better than the conventional system. The paper also describes successful application of the system to commercial high-rise buildings. 相似文献
998.
Translated from Fiziko-Khimicheskaya Mekhanika Materialov, No. 3, pp. 111–112, May–June, 1992. 相似文献
999.
Stekloplastik—Sertifikat Corporation Moscow. Translated from Khimicheskie Volokna, No. 2, pp. 58–59, March–April, 1994. 相似文献
1000.
We present the results from tuning a PI controller and two differentiators for a three-loop steam temperature regulation system with two leading speed signals. The calculation was carried out with a numerical method using a simulation model and with the application of the authors’ version of the evolutionary optimization algorithm. 相似文献