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THE CELLULAR DOCTRINE IN
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THE CELLULAR See also:DOCTRINE IN See also:PATHOLOGY The cellular pathology is the pathology of to-See also:day; indeed, See also:protoplasm—its vital characteristics under abnormal influences and its decay—will be regarded most likely as the basis of pathology in all See also:time. According to our See also:present knowledge of physiological and pathological processes, we must regard the See also:cell as the ultimate biological unit—a unit of structure and a unit of See also:function; this was first put forward by See also:Schleiden in 1838, and by See also:Schwann in 1839, but we owe to See also:Virchow the full recognition of the fundamental importance of the living cell in all the processes of See also:life, whether in See also:health or disease. When Virchow wrote, in 185o, " every See also:animal presents itself as a sum of vital unities, every one of which manifests all the characteristics of life," he expressed a doctrine whose sway since then has practically been uninterrupted. The somatic cells represent communities or republics, as it were, which we name See also:organs and tissues, but each cell possesses a certain See also:autonomy and See also:independence of See also:action, and exhibits phenomena which are indicative of vitality. Still, it must be See also:borne in mind that this alleged autonomy of action is said to be founded upon an erroneous supposition, on the supposition that each cell is structurally, and it may be said functionally, separated from those in its neighbourhood. It is well known that in the See also:vegetable See also:kingdom the protoplasm of one cell frequently overflows into that of cells adjacent—that there is, as it were, a continuous network of protoplasm (idioplasm of Nageli) prevailing throughout vegetable tissues, rather than an See also:aggregation of isolated See also:units. The same inter-communication prevails between adjacent cells in some animal tissues, and more particularly in those which are pathological, as in the See also:case of the See also:epithelial cells of See also:cancer. Assuming, with See also:Sedgwick and others, this amassed and See also:bound See also:condition of the tissues to be true, it would be necessary to reject the cell-doctrine in pathology altogether, and to regard the living basis of the organism as a continuous substance whose parts are incapable of living independently of the whole. Until, however, further See also:evidence is forthcoming in support of this syncytial theory of structure, it would be unwise to regard it as established sufficiently to constitute a serviceable working See also:hypothesis; hence, for the time being, we must accept the assertion that the cell represents the ultimate See also:tissue-unit. Our present day See also:definition of a cell is a See also:minute portion of living organized substance or protoplasm. The cells met with in morbid parts which are in a See also:state of active vitality are built up of the same components as those found in normal tissues (PI. I.).1 Thus they are See also:pro- Structure of vided with a See also:nucleus which is the centre of cell activity; Pathological both of the reproductive and chemical (metabolic) pro- Cells. cesses which occur in the cell protoplasm. The executive centre 1 DESCRIPTION OF See also:PLATE I. Additional information and CommentsThere are no comments yet for this article.
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