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901.
The aim of this study was, (1) to characterize the serum protein binding of lerisetron, a new 5-hydroxytryptamine (5-HT3) receptor antagonist under investigation as an antiemetic agent, and (2) to measure the percentage of unbound lerisetron in cancer patients. The binding parameters were determined in human serum albumin (HSA), alpha1-acid glycoprotein (AAG) and in pooled serum from six healthy volunteers. Concentrations of lerisetron ranging from 50 ng/ml to 2 microg/ml were used. The serum protein binding of 14C-lerisetron (2 microg/ml) was determined by ultrafiltration in three groups of individuals. Group I comprised healthy subjects (n = 11), group II comprised cancer patients undergoing radiotherapy (n = 9), and group III comprised cancer patients receiving chemotherapy (n = 18). The unbound concentration of lerisetron was measured in all samples by liquid scintillation counting. Concentrations of both AAG and HSA were also measured in all serum samples. The drug was extensively bound in pooled serum, involving a nonsaturated process. In HSA, lerisetron was also highly bound (4.04+/-0.8% unbound) and the protein binding was essentially unchanged within the studied concentration range of lerisetron. The extent of binding to AAG was high but significantly lower than in serum and in HSA and was also independent of lerisetron concentration. The unbound lerisetron was significantly decreased in group II cancer patients when compared with group I subjects (2.38+/-0.64% vs 3.70+/-0.70%; P < 0.001). No significant changes in lerisetron binding were observed in group III patients. HSA was diminished in both groups of patients and AAG was only significantly increased in group II. Unbound lerisetron was correlated with AAG in group II and with HSA in group III.  相似文献   
902.
903.
904.
This paper presents the finite element analyses of magnetohydrodynamic (MHD) flow and its application to liquid lithium blanket design of a fusion reactor. In the preliminary analyses of MHD flow, we are concerned with both coupling and uncoupling problems between the magnetic and velocity fields. Next, the steady state liquid lithium flow in the blanket of fusion reactor is analysed with the practical simplification of the MHD equations for a typical fusion reactor. In addition, thermal and mechanical behaviors of the blanket are also discussed. Finally, we study the transient problem of MHD flow when the plasma current linearly drops in a short time, where we take account of the compressibility of liquid lithium because the phenomena should be considered as a kind of shock caused by electromagnetic forces, and the transient magnetic and electric fields are also solved with axisymmetric equations of vector potential as inputs for the analysis.  相似文献   
905.
In this paper, to achieve both damping of power system oscillation and terminal voltage control simultaneously on a multimachine power system, we propose a decentralized H excitation controller. In the proposed method, H control via the Normalized Coprime Factorization approach is used to achieve the proposed design idea. By the Normalized Coprime Factorization approach, the weighting function in H control design is simplified, and output feedback controllers that take into account the realities and constraints of the power systems are designed. The proposed controller is subjected to model reduction of H controllers, and is transformed to a discrete system to perform digital control by computer systems in consideration of application to a real system. We verify that the proposed excitation controller can achieve both damping of power system oscillation and terminal voltage control by computer simulations of a multimachine power system. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(1): 33–41, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10254  相似文献   
906.
907.
A new photochromic ZrO2 precursor solution was prepared using zirconium tetra-n-butoxide, 4-(phenylazo)benzoic acid and ethyleneglycol monomethylether. The density functional theory (DFT) calculation has identified that the structure of the synthesized precursor molecule changed by UV irradiation. Four types of thin films were prepared using the ZrO2 precursor solution with and without UV irradiation and applying an electric field. It was found that the surface morphology of thin films changed by applying UV irradiation to the precursor solution and an electric field.  相似文献   
908.
A sol–gel process has been developed to coat micron-sized ZnS:Cu,Au,Al phosphors with a smooth and uniform layer of amorphous titania having nanosize thickness. The titania nanocoating is based on the hydrolysis and condensation of titanium tetrabutoxide Ti(OBu)4. Acetylacetone was used to decrease the reactivity of Ti(OBu)4. The experimental variables such as water concentration, the amount of ZnS particles, and reaction time were investigated. The thickness of the titania nanocoating was homogeneous and can easily be controlled from 20 to 54 nm by adjusting the experimental variables. The as-prepared titania nanocoating was amorphous phase and could be crystallized to anatase phase upon heating at 500 °C in Ar atmosphere.  相似文献   
909.
We have evaluated the electrical performance of bulk acoustic wave (BAW) resonators in the range of resonance frequency from 5 to 20 GHz. The BAW resonators, consisting of a piezoelectric AlN film and top and bottom electrodes of Al/Ti films, were designed and prepared in the fundamental thickness-extensional mode. The value of effective coupling coefficient () up to 6% and constant QF factors were achieved in these frequency ranges, which closely followed the theoretical calculation. It was found that AlN films were suitable for high frequency application because of their superior piezoelectricity even in the ultra thin region of 200 nm thickness.  相似文献   
910.
The magnetization reversal process of an ordered Co nanorod array is shown using the images obtained from successive in-field magnetic force microscope (MFM) measurements. The magnetization reversal model is discussed according to local and whole magnetization reversal properties measured by the polar magneto-optical Kerr effect (PMOKE) and an alternating gradient magnetometer (AGM), respectively. Additionally, the dipolar field was probed using in-field MFM measurements. By removing the effect of the dipolar field, an intrinsic switching field distribution (SFD) is shown in a map with a hexagonal array. A detailed study of the dipolar field in ordered nanorod arrays with various diameters and pitches was carried out by numerical calculations.  相似文献   
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