Compensatory effect

Compensatory effects or early effects of dubious significance, without adverse health consequences... 

In this scheme, OELs should be a dose somewhere between compensatory effects, in which the organism is able to detoxify, metabolize, or excrete the substance, and early impairment. Although there may be profound differences of opinion as to what constitutes this dose, this approach leads to the conclusion that available scientific data permits identification of a clear threshold dose below which exposure to the substance in question is not expected to lead to adverse effects. 

The observed contradictions are down to variations in catalyst purity, the level of oxygen contamination, and compensatory effects from the presence of excess phosphine. Hence, freshly... 

Due to the superposition of various other biological, physiological and physical parameters used in modelling, the published exposure-dose conversion factors range from 2 to 120 mGy per WLM. However, a sensitivity analysis indicated that for most indoor exposure situations compensatory effects can reduce this range to about 5 to 10 mGy/WLM for the indoor situations occurring most frequently (OECD/NEA, 1983). 

It is seen that the rate constant ks is lower for compounds with electron-accepting substituents than with electron-donating substituents, which implies a dependence of the rate of Ar20 and R02 recombination on the electron density at the para- and ort/zo-positions of the benzene ring of the phenoxyl radical. The activation energies of this reaction vary from -33 to 10 kJ mol-1 however, the concurrent variation in the pre-exponential factor from 103 to 1010 L mol-1 s-1 causes a strong compensatory effect. It can also be seen that phenoxyl radicals readily react with peroxyl radicals k= 10s—109 L mol-1 s-1), whereas the disproportionation of peroxyl radicals is sufficiently slower (see Chapter 2). Hence, during the oxidation of hydrocarbons in the presence of phenols when k7[ArOH] > /c2[RH], the recombination reaction of ArO with R02 is always faster than the reaction of disproportionation of peroxyl radicals. 

Noradrenalin turnover is decreased with antidepressant treatment. This is a compensatory effect of elevated intra-synaptic noradrenalin causing feedback inhibition of tyrosine hydroxylase. This effect has been consistently observed with noradrenergic-specific antidepressants, as expected, but has also been reported with serotonergic-specific... 

The compensatory effect of cholesterol observed in D407 cells have also been demonstrated in other cell lines (Cho et al. 1998 Holleran et al. 1998) and may well be a consequence of tamoxifen-induced severe inhibition of lanosterol (to cholesterol)-converting enzymes. In rat liver preparations and CHO cells, sterol A8-isomerase (IC50 0.21-0.15. iM) was the most sensitive... 

Poor translation of in vitro to in vivo activity (e.g., due to poor accessibility of the target, up-/downregulation of target or endogenous ligand or compensatory effects). 

Finally, one should note that all of the agents that lower blood pressure by altering sympathetic function can elicit compensatory effects through mechanisms that are not dependent on adrenergic nerves. Thus, the antihypertensive effect of any of these agents used alone may be limited by retention of sodium by the kidney and expansion of blood volume. For this reason, sympathoplegic anti hypertensive drugs are most effective when used concomitantly with a diuretic. 

The large number of derivatives of 1 and 2 in which the ruthenium core is preserved indicates that the presence of a carbide atom makes a significant contribution to the stability of the cluster.24 Single crystal X-ray diffraction studies of some derivatives of 1 and 2 reveal that the carbide atom is located slightly closer to the new ligand. This has been attributed to an electronic compensatory effect of the carbide atom when the carbonyl ligands are replaced by poorer 77-acceptor ligands.25... 

A basic understanding of the interactions of autonomic nerves with each other and with their effector organs is essential for an appreciation of the actions of autonomic drugs, especially because of the significant reflex (compensatory) effects that may be evoked by these agents. 

Knockout systems ethylnitrosourea induced uterine tumors in p53 knockout mice. susceptible to methylcholanthrene-induced tumorigenesis. [113] well studied. Can be created for most cytokines or effector cells. May provide strong proof of concept. genes. Compensatory effects may mask deficit. All or nothing effect may overestimate hazard. 

Given the fact that the cooperativity, both positive and negative, amounts to only small amounts, and coupled with the compensatory effects of positive vs negative... 

Less stable structural isomers of a fluxional process are isolated thanks to the compensatory effect of external interactions in the solid Ordered and disordered crystals of the same molecules may show different crystallographic symmetry, e.g. crystallize in different space groups The same (chemically relevant) molecular ion is crystallized in different crystals with a different type/number of counterions The same network ligand yields different... 

Increase in blood volume this occurs with any drug that reduces peripheral resistance (increases intravascular volume) or cardiac output (reduces glomerular flow) due to activation of the renin-angiotensin system. The result is that cardiac output and blood pressure rise. Adding a diuretic in combination with the other drug can prevent this compensatory effect. 

Z2. Zuckerkandl, E., Compensatory effects in the synthesis of hemoglobin polypeptide chains. Cold Spring Harbor Symp. Quant. Biol. 29, 357-374 (1964). 

Compensatory effect This effect maintains overall function without enhancement or significant cost. Increased respiration due to metabolic acidosis is an example of a compensatory effect. 

The most common approach to this problem is to run only one experiment with each reagent under "standardized" conditions in which 1, 2 and 3 are maintained at fixed levels. A moment of reflexion reveals that this may be misleading. The type of reagent can interact with the variables and give compensatory effects e.g. one reagent may be useful at a low temperature but may have a poor selectivity at ambient temperature, while another reagent may be insensitive to temperature variation. 

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