Dose-response relationships for

FIGURE 5.51 Dose-response relationships for methyl mercury.(Used with permission.)... 

Himnan DJ Tolerance and reverse tolerance to toluene inhalation effects on open-field behavior. Pharmacol Biochem Behav 21 625-631, 1984 Hinman DJ Biphasic dose-response relationship for effects of toluene inhalation on locomotor activity. Pharmacol Biochem Behav 26 65-69, 1987 Hormes JT, Filley CM, Rosenberg NL Neurologic sequelae of chronic solvent vapor abuse. Neurology 36 698—702, 1986... 

Further monitoring for birth defects in humans exposed to trichloroethylene are needed, especially in populations in which exposure concentrations could be determined. Additional studies in animals that develop dose-response relationships for particular defects and trichloroethylene exposure, as well as exposure to metabolites of trichloroethylene, are needed. 

Nomiyama K, Nomiyama H. 1977. Dose-response relationship for trichloroethylene in man. Int Arch Occup Environ Health 39 237-248. 

Stages in hazard characterization according to the European Commission s Scientific Steering Committee are (1) establishment of the dose-response relationship for each critical effect (2) identification of the most sensitive species and strain (3) characterization of the mode of action and mechanisms of critical effects (including the possible roles of active metabolites) (4) high to low dose (exposure) extrapolation and interspecies extrapolation and (5) evaluation of factors that can influence severity and duration of adverse health effects. 

Roels HA, Lauwerys R. 1987. Evaluation of dose-effect and dose-response relationships for lead exposure in different Belgian population groups (fetus, child, adult men and women). Trace Elements in Medicine 4 80-87. 

Having established a suitable timepoint for the component of interest, the researcher may find it useful to examine the dose-response relationship for the agonist under study. 

Cohen, B.L., Surveys of Radon Levels in U.S. Homes as a Test of the Linear-No Treshold Dose-Response Relationship for Radiation Carcinogenesis, this volume (1987). 

A Test of the Linear-No-Threshold Dose-Response Relationship for Radiation Carcinogenesis... 

Human Cytogenetic Dosimetry A Dose-Response Relationship for Alpha Particle Radiation from Am-241, Health Physics 37 279-289 (1979). 

Kamiguchi Y., and K. Mikamo, Dose Response Relationship for Induction of Structural Chromosome Aberrations in Chinese Hamster Oocytes After X-Irradiation, Mutation Research 103 33-37 (1982). 

Fig. 12. Dose-response relationship for the effect of l MCe on the lung and other organs after inhalation of labeled fused aluminosilicate particles (as of September, 1978)...

The available data for deriving dose-response relationships for 144Ce are relatively limited. A complicating feature is that the spectrum of diseases produced is dependent upon the form of the 144Ce entering the body and the resultant radiation dose. This is apparent from data in Table 23 in which several different and competing diseases were produced by inhaled 144CeCl3. Additional factors that confuse the interpretation of internal emitter dose-response studies in laboratory... 

Carcinogenic solvents, 23 113 Carcinogenic substances, dose-response relationship for, 25 236. See afso Carcinogens... 

Figure 4.6. Log dose-response relationships for the effects of synthetic neurotensin, synthetic brady-kinin, and various preparations of NRP on the release of histamine from isolated rat mast cells [73], Each point is the mean obtained for two separate incubations.

Ideal for studying the dose-response relationship for QT interval prolongation taking into account all the pharmacological properties of a compound The dog model is one of the most widely used anesthetized rabbits (especially female rabbits) have also been proposed for high sensitivity It provides complementary information with respect to in vitro tests (activity of metabolites, measurement of plasma drug concentrations, calculation of the volume of distribution) Possibility to induce experimental TdP... 

No information is available on the effects of intermediate-duration oral exposure in humans, but two animal studies (Boorman et al. 1986 Danse et al. 1984) provide sufficient data to identify the main target tissue (the stomach epithelium) and to define the dose-response relationship for this effect. These studies are suitable for derivation of an intermediate oral MRL, but further studies would still be helpful to search more specifically for possible subclinical neurological effects. This is important since neurological effects appear to be the most sensitive effect by the inhalation route, and people may be exposed to low levels of bromomethane in drinking water drawn from contaminated groundwater sources. No information is available on intermediate- duration dermal exposure to bromomethane. However, humans are not likely to experience significant dermal exposures to bromomethane near waste sites, so research in this area does not appear to be essential. 

Bryant CA, Farmer A, Tiplady B, Keating J, Sherwood R, Swift CG, Jackson SH. (1998). Psychomotor performance investigating the dose-response relationship for caffeine and theophylline in elderly volunteers. EurJ Clin Pharmacol. 54(4) 309-13. 

Figure 3.3 teaches some additional and important features of dose-response relationships. Such relationships are depicted for two different compounds (A and B), and responses in two different species, rats and guinea pigs, are shown for compound A. Because the dose-response relationship for compound B is to the right of that shown for A, we can conclude that B is less toxic than A, at least for the particular response plotted here (according to our principles, such a pattern could he reversed for some other manifestation of the toxicity of A and B). As seen in the figure, toxic responses to B consistently occur only at higher doses than they do for A, so B is less toxic. 

Table 6.2 Dose-response relationship for saccharin-induced bladder tumors in rats...

Dose-response relationships for two animal carcinogens, strikingly different in potency, are presented in Tables 6.2 and 6.3. The type of information presented in the tables is the usual starting point for risk assessments as we shall see, human exposures to these carcinogens are very much less than the NOAELs and LOAELs from the animal data. 

As has been emphasized so many times in the preceding chapters, these various manifestations of toxicity all display dose-response characteristics, where by response we refer to the incidence or severity of specific adverse health effects. As we demonstrated in earlier chapters, toxic responses increase in incidence, in severity, and sometimes in both, as dose increases. Moreover, just below the range of doses over which adverse effects can be observed, there is usually evidence for a threshold dose, what we have called the no-observed adverse effect level (NOAEL). The threshold dose must be exceeded before adverse effects become observable (Chapter 3). Deriving from the literature on toxic hazards, descriptions of the dose-response relationships for those hazards comprise the dose-response assessment step of the four-step process. 

As intake increases above the range of adequacy a region will be reached at which the adverse effects of excessive intake will begin to manifest themselves. Figure 9.1 depicts these interesting dose-response curves, and the curve at the right side of the figure represents a typical dose-response relationship for toxicity, in this case caused by excessive intakes of substances we cannot live without at lower doses. 

Larson et al. (1995b) further examined the dose-response relationship for chloroform-induced cytotoxicity and cell proliferation in the liver of female Fisher 344 rats via gavage. Animals received chloroform in com oil at doses of 0, 34, 100, 200, or 400 mg/kg/day for 3 weeks (5 days a week). At completion of... 

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