Concentration vs. time curves

AUC, area under the concentration vs time curve N/A, not applicable. 

Fig. 6. Simulated plasma drug concentration vs. time curves after intravenous administration (a) showing the j-axis in numeric scale, and (b) showing the curve when the v-axis is converted to logarithmic scale.

Fig. 13. Plasma drug concentration vs. time curve after administrations of multiple oral doses at 8-hour intervals.

Figure 5.2 Plasma concentration curve of drug after single and repeated administration Csj. nax, maximal steady-state plasma concentration after repeated administration Css av, average steady-state concentration after repeated administration Css mm- minimal steady-state concentration after repeated administration n. maximal plasma concentration after single oral dose t Inax. time to maximal concentration after single oral dose t plasma half-life after single oral dose AUC, area under the concentration vs. time curve...

Fig. 1.4.3 Drug concentration vs time curve of repeated dosing.

The pulmonary delivery of rhG-CSF (18.8 kDa) and two PEG conjugates of rhG-CSF (PI, 81.5 kDa and P2, 146.8 kDa) was investigated in rats (Niven et al. 1994). Comparison of white blood cell responses after IT instillation of 500 pg/kg PI and P2 and rhG-CSF alone, demonstrated a greater response for more substituted PEG-rhG-CSF than rhG-CSF alone. The plasma concentration vs. time curve showed... 

The bioavailability of a drug by various routes may also be determined by comparing the area under the curve (AUC) obtained from the plasma concentration vs. time curve after intravenous and other routes of administration 9... 

Fig. 2.10 Amounts of 02 consumed as a result of photocatalytic reactions in ethanol-containing aqueous solution, with and without 0.1 M phenol present, under UV irradiation for 1 min. The amount of 02 consumed was estimated using a finite difference method from the oxygen concentration vs. time curves (light intensity, 2.5 mW/cm2 microelectrode potential, -1 V vs. SCE).

The rate constant k and the order of reaction can be determined from the plot of log (-d[A] / dt) vs. log [A], Figure 5.7 illustrates these procedures. First, the rate is determined from the concentration vs. time curve (Figure 5.7a). Second, the rate vs. concentration is plotted in a log-log plot (Figure 5.7b). The slope and the y-intercept furnish the order of reaction and the rate constant, respectively. 

FIGURE 4.3 Hypothetical plasma concentration-vs.-time curve after a single oral drug dose. Calculation of the area under the plasma level-vs.-time curve (AUC) requires extrapolation of the elimination-phase curve beyond the last measurable plasma concentration, as shown by the dotted line. 

Distributed pharmacokinetics is characterized not only by spatially dependent concentration profiles but also by dose-response relationships that become spatially dependent. For example, biological responses such as cell kill are often quantified as functions of area under the concentration-vs.-time curve (ALIC). In compartment models, response is frequently correlated with the area under the plasma-concentration-vs.-time curve, where... 

PK = pharmacokinetic Cl = clearance AUC = area under the plasma concentration vs. time curve ERBT = erythromycin breath test IM = intramuscular IV = intravenous... 

An absorption study is performed to estimate the rate and extent of absorption of the test substance. These data are usually obtained from the blood concentration vs. time curve. 

The slope of the concentration vs. time curve is the derivative of the concentration with respect to time. 

PKpharmacokinetics, maximum plasma concentration, CL systemic clearance, AUC area under the concentration vs. time curve, SNP single-nucleotide polymorphism... 

Upon opening the ozone chamber to introduce samples, a concentration gradient was produced. For this reason the subsequent time involved for equilibrium to be reestablished, exposure time was not used as the only gauge of exposure in reciprocity measurements. Under these circumstances, the area under the concentration vs time curve appears to be a better measure of exposure of the sample to ozone. This area factor was kept constant over a range of concentration conditions. 

The RTD for a given reactor and flow rate can be established from response-type experiments. In these experiments the concentration of an inert tracer is disturbed in the feed stream and its effect on the effluent stream is measured. The three most common perturbations are a step function, a pulse (square wave), and a sinusoidal wave. The relationships between the observed concentration-vs-time curves and the RTD are examined here for step functions and pulses. The analysis of sinusoidal perturbations is more complex but is available in the literature. ... 

A-Allyl cysteine (SAC) is thought to undergo first-pass metabolism in rats based on nonlinear increases in AUC (area under the plama concentration vs time curve) after oral administration. SAC is likely metabolized to TV-acetylSAC (ALMA) by acetyltransferase in the liver and kidney. The high concentration of SAC in rat kidney has been attributed to conversion of TV-acetyl -SAC back into SAC by kidney acylase. Thirty to fifty percent of the SAC dose is... 

The elimination half-life of the "second component" discussed previously was 1.9 h and the mean area under the concentration vs time curve (AUC) was 8.2 mg/L h after a single oral dose of 320 mg (De Bemardi Di Valserra et al., 1994). The AUC of the "second component" produced by a 640-mg rectal dose of saw palmetto extract was 10 mg/L x h, and plasma levels were detectable up to 8 h post-dose (De Bernardi Di Valserra and Tripodi, 1994). 

AUC area under the plasma concentration vs time curve, autoantibodies antibodies directed against self tissues or constituents, autoimmune immune response in which antibodies are directed against the organism itself, autoradiography use of radiolabelled compounds to show distribution in a tissue, organ or even whole animal. 

The function f(t) is straightforwardly related to the experimental tracer response curve for a slug input, the downstream concentration vs. time curve is proportional to the function f(t). Response curves for different modes of input theoretically convey equivalent information, although certain inputs are experimentally convenient to carry out. Thus, redoing tracer experiments for different inputs gives no added information about the flow. 

In several runs the adsorption stage was followed by a desorption stage, using dry nitrogen, that was carried out at the adsorption operating conditions. Typical normalized concentration vs. time curves for both adsorption and desorption are shown in Figure 2. 

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