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231.
232.
Effects of oral administration of NaCl on salivary and systemic clearance of Li+ were investigated following bolus intravenous administration of LiCl in male beagle dogs. Fifty ml of NaCl solution (100 meq/l) was administered orally 7 times at 1 h intervals. Gustatory stimulation of salivation was continued for 390 min using citric acid solution. Saliva was collected by means of permanent fistulae for parotid and mandibular-sublingual glands. Salivary clearance of Li+ was markedly increased by continuous stimulation of salivation, and was enhanced further after oral administration of NaCl solution. Renal clearance of Li+ showed a decreasing tendency under continuous salivation compared with the condition without gustatory stimulation; however, this decreasing tendency disappeared after oral administration of NaCl solution. Consequently, systemic clearance of Li+ was increased due to the contribution of increased salivary clearance. Enhancement of salivary Li+ clearance after administration of NaCl suggests the salivary excretion mechanism of Li+ may include a reabsorption process, like its renal excretion. Administration of NaCl solution had similar effects on salivary and systemic clearances of K+ to those on Li+ clearances, and a significant correlation was observed between Li+ and K+ clearances of both salivary gland and kidney.  相似文献   
233.
This paper considers the following charging policy for a battery to back up memories of a computer system: If the voltage of a battery is lower than a prespecified threshold level when the power is on, a battery is charged for a fixed time T. Using the probability theory, an availability of the system is derived and an optimal time T* to maximize it is discussed. A numerical example is finally given.  相似文献   
234.
The stochastic properties of baseline noise in HPLC systems with a UV photo-diode array, photo-multiplier and gamma-ray detector were examined by dividing the noise into auto-correlated random process (Markov process) and an independent process (white noise). The present work focused on the effect of the stochastic noise properties on a theoretical estimation of the standard deviation (SD) of area measurements in instrumental analyses. An estimation theory, called FUMI theory (Function of Mutual Information), was taken as an example. A computer simulation of noise was also used. It was shown that the reliability (confidence intervals) of theoretical SD estimates mainly depends on the following factors: the ratio of the white noise and Markov process occurring in the baselines; the number of data points used for the estimation; the width of a target peak for which the SD is estimated.  相似文献   
235.
236.
[1,1-18O2]11-Dehydrothromboxane B2 (11-dehydro-TXB2) was prepared by repetitive base-catalyzed hydrolysis of the lactone ring of its [1,1,11-18O3]-analogue, and evaluated for its suitability as an internal standard in gas chromatography/selected ion monitoring (GC/SIM) of 11-dehydro-TXB2. Use of the present [18O2]-analogue as an internal standard may make it a suitable candidate for specific immunoaffinity purification followed by GC/SIM.  相似文献   
237.
238.
Due to the large mass of top quark, CP violation in the top-quark decay is sensitive to the interactions mediated by Higgs bosons. We consider CP violation in tW + b decay by calculating consistently in unitary gauge the CP-violating up-down asymmetry of the leptons from W boson decays in tW + b, defined by Grz?dkowski and Gunion, in the two-Higgs doublet model with CP-violating neutral sector. The asymmetry is shown to be at most of the order of (1–4) × 10-4 for tan β = 1.0, where tan β is the ratio of vacuum expectation values for the two neutral Higgs bosons.  相似文献   
239.
In a plasma wake wave generated by a high power laser, modulations of the electron density take the shape of paraboloidal dense shells, moving almost at the speed of light. A counterpropagating laser pulse is partially reflected from the shells, acting as relativistic flying mirrors, producing a time-compressed frequency-multiplied pulse due to the double Doppler effect. The counterpropagating laser pulse reflection from the plasma wake wave accompanied by its frequency multiplication (with a factor from 50 to 114) was detected in our experiment.  相似文献   
240.
Brownian dynamics simulations of shear flows are carried out for various suspensions of ellipsoids interacting via the Gay-Berne potential. In this simulation all the systems of the suspension are in a liquid crystalline phase at rest. In a shear flow they exhibit various motions of the director depending on the shear rate: the continuous rotation, the intermittent rotation, the wagging-like oscillation, and the aligning. The director is almost always out of the vorticity plane when it rotates, that is the kayaking. The number density of the system and the inter-particle potential intensity significantly affect the shear rate dependence of orientation. In particular, the continuous rotation of director is maintained to higher shear rates for the system with a stronger potential. Furthermore, the rheological properties are examined. The shear-thinning in viscosity is observed, but the negative first normal difference is not obtained.  相似文献   
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