Milieu interieur

As multicellular life forms reached a sufficient degree of complexity, they improved their physical separation from the water medium, allowing migration to land and continued evolution in novel environments. In terrestrial plants and animals, water is no longer both external and internal, but solely the internal milieu, the milieu interieur, in constant flux with the environment yet carefully separated from it Such, in a nutshell, is the biophysical role of water as a medium. 

The somatic nervous system is composed of sensory afferents and motor efferents and serves to perceive external states and to modulate appropriate body responses. The autonomic nervous system (ANS), together with the endocrine system, controls the milieu interieur. It adjusts internal organ functions to the changing needs of the organism. The ANS operates largely autonomously, beyond voluntary control, at the subconscious level. Its central components reside in the hypothalamus, brain stem, and spinal cord. The ANS has sympathetic and parasympathetic branches. Both are made up of afferent, mainly in the vagus nerve, and efferent fibers. 

The concept of two compartments, the external medium and the milieu interieur, which undergo mixing (Weber and Woodhead, 1970) is almost certainly an oversimplification and has been brought into question by Land et al. (1977) and by Goreau (1977). Many factors, both environmental and internal, affect the relative amounts of C and fixed in the coral skeleton with the result that precise interpretations of the ratios are not... 

The systemic responses that accompany trauma and inflammation are known as the acute phase response (D16). The present evidence supports the idea that this is an adaptive response conditioning the milieu interieur so that inflammation and healing may progress optimally. A complex array of hormones and cytokines induces and controls the components of this response and it is rapidly becoming clear that these and the nervous system are closely integrated. 

A number of studies of the mucosal mechanisms of lithium absorption in the gastrointestinal tract have shown that lithium [28,29], and indeed other metals [30-32], transfers across the tract not by passage through the cell but by paracellular transport via the tight junctions and pericellular spaces. Cellular transport mechanisms and carriers identified in cells may thus exist only for the domestic requirements of the intestinal cells themselves, which in turn protect their own milieu interieur by, as far as practicable, avoiding accumulation of externally derived metals [33]. 

Polymers entering the milieu interieur of an organism cannot move randomly but their movement is controlled by anatomical and physiological barriers. In pharmacokine-... 

Maintenance of a constant composition of the extracellular fluid is important because it provides a stable environment for the cells of the body. This was first recognized by Claude Bernard, who described the extracellular fluid as the milieu interieur or the internal environment . 

Claude Bernard (1813-1878) was bom of a modest family in the town of Saint Julien on the Rhone he attended a Jesuit college at Villefranche and then became a pharmacist s assistant in Lyon. Bernard is best known for his book on experimental physiology, in which he outlined a number of the major concepts that he felt were critical to the pursuit of physiologic sdence. In particular, his delineation of the milieu interieur has remained one of the critical physiologic observations ever made. 

Kidney maintenance of milieu interieur, fluid and electrolytes, acid-base balance... 

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