Physiological classifications

Physiological Classifications of Contaminants. The physiological classification of air contaminants is difficult, because the type of action of many gases and vapors depends on concentrations (55). For example, a vapor at one concentration may exert its principal effect as an anesthetic but, at a lower concentration, the same vapor may iujure the nervous system, the hematopoietic (blood-forming) system, or some visceral organ (see Toxicology). 

The rate of action of a chemical agent is the rate at which the body reacts to or is affected by that agent. The rate varies widely, even to those of similar tactical or physiological classification. For example, blister agent HD causes no immediate sensation on the skin. Skin effects usually occur several hours later (some cases result in delays of 10-12 days before symptoms appear). In contrast, lewisite produces an immediate burning sensation on the skin upon contact and blistering in about 13 h. Decontamination immediately (within 4-5 min) will prevent serious blister agent effects. 

R11. Rixen, S., Siegel, J. H., and Friedman, H. P Sepsis/SIRS, physiologic classification, severity stratification, relation to cytokine elaboration and outcome prediction in posttrauma critical illness. J. Trauma 41,581-598 (1996). 

The term prodrug (see section 2.7.1 and 9.8) is often used for drugs whose active form is produced by enzyme or chemical action at or near to its site of action. However, it is emphasized that other classifications, such as the nature of the illness and the body system on which the drug acts (physiological classification),... 

A detailed analysis of coding properties of ORNs in B sensilla of palps and antennae has revealed 22 functional types of sensilla, most with two ORNs and one with four (de Bruyne et al, 1999,2001). Hierarchical cluster analysis indicates that populations of ORNs can be categorized in distinct classes, with differences between classes larger than within (de Bruyne et al, 1999). The physiological classification of this large set of neurons, representing more than half of all... 

This classification arranges chemical agenfs according to the effiHTts they produce upon the living body. Both during and. iiiice the late war, the physiological classification sy. tems of the prineipa) countries ha.s differed considerably in order to coiu >are these. y.stems, we shall review briefly the salient point.s of eacli. 

On comparing the oeveral World War physiological classification with those of the postwar period, we find that there wa.s much greater divergence among the various systems during the war than since then. 

In addition to the above classes of gases, there are also the smoke and incendiary agents but, as they produce only slight or incidental physiological effects, they are usually omitted from the physiological classifications. 

About 6000 chemical entities can be used, in various pharmaceutical formulations, to treat human or animal diseases all attempts towards their classification represent arbitrary procedures. The first reason for that is that not a single drag has ever been encountered which exhibits only one biological activity. The antimalarial drug chloroquine is also active on some inflammatory processes, the anxiolytic benzodiazepines possess antiepileptic properties, etc. On the other hand, the scientific communities have different needs a chemical classification may sometimes be very useful to medicinal chemists but strictly of no interest to a social security employee. Conversely pharmacologists and physicians will probably prefer the physiological classification. 

The therapeutical action of diuretics has been attributed to their hydrophobic character, among other properties. As commented, the therapeutical and physiological classifications of diuretics are correlatoi. The site of action for high efficacy diuretics is the loop of Henle, for intermediate efficacy diuretics is the distal tubule and for low efficacy diuretics is the proximal and distal tubules and the collecting duct. It has been shown that MLC with SDS mobile phases and C18 colurrms offers a scale for hydrophobicity, which leads to a further correlation between the retention and the sites of action of diuretics within the nephron. The site of action of those diuretics showing the lower retention in MLC is the proximal... 

Physiological Classification This extensive method of classification uses potential human injury as a means of categorizing certain agents. Below are several physiological classifications. 

Physiological classification systems examine the way body parts move. 

Krimer LS, Zaitsev AV, Czanner G et al (2005) Cluster analysis-based physiological classification and morphological properties of inhibitory neurons in layers 2-3 of monkey dorsolateral prefrontal cortex. J Neurophysiol 94 3009-3022... 

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