VARYING ACTIVITY OF THE NUTRITIVE PROCESSES. 457 



die and degenerate. The process of Granulation and Suppuration appears to 

 differ from that of simple Reparation (the modeling process of Dr. Macartney) 

 in this, that a large part of the exudation-corpuscles deposited on the wounded 

 surface degenerate into pus in the former case, whilst none are thus wasted in 

 the latter ; hut that the existence of inflammation occasions a more copious 

 supply of fibrin in the former case, and increases its tendency to become or- 

 ganized ; the filling-up of a wound with granulations being thus a much more 

 rapid process than that renewal of the completely-formed Tissues which may 

 take place in the absence of Inflammation. The imperfect character of the 

 granulation-structure is shown, by the almost complete disappearance of it, 

 after the wound has closed over. The portion of it in immediate contact with 

 the subjacent tissue, however, appears to undergo a higher organization ; for 

 it becomes the medium by which the Cicatrix is made to adhere to the bottom 

 of the wound. It is very liable to undergo changes which end in its disinte- 

 gration ; as is evident from the known tendency to re-opening, in wounds that 

 have been closed in this manner. 



VII. Varying Activity of the Nutritive Processes. 



602. Without any change in the character of the nutritive processes which 

 we have been describing, there may be considerable variations in their degree 

 of activity; and this, either as regards the entire organism, or individual parts, 

 though most commonly the latter. These variations may be so considerable 

 as to constitute Disease ; though there are some which take place as part of the 

 regular series of physiological phenomena. Thus, the Nutritive processes 

 should have a degree of activity more than sufficient to supply the waste of 

 the body, during the whole period of infancy, childhood and adolescence, until, 

 in fact, its full dimensions are attained ; whilst, on the other hand, they are 

 usually less rapid than the disintegrating processes in old age, so that the bulk 

 of the body diminishes. Now as the waste of the body, so far from being 

 more rapid in old age than in childhood, is much less so, it follows that the 

 difference in the activity of the nutritive processes in these two states must be 

 very considerable ; and this is manifested, not only in the greater demand for 

 food which exists in the child (relatively to the bulk of its body), but also in 

 the greater quickness and facility with which injuries are repaired. Local 

 variations may also occur, as part of the regular train of vital actions in the 

 adult ; thus we perceive an enormous increase in the amount of tissue con- 

 tained in the Uterus and Mammary glands during pregnancy, and a decrease 

 in the bulk of the Thymus gland after the first year of infancy. Now in these 

 cases we see, that increased nutrition is invariably connected wit'h increased 

 Functional activity, and diminished nutrition with diminished functional acti- 

 vity ; and this we shall find to be the constant rule, in regard also to those vari- 

 ations which must be considered as abnormal. 



603. Increased Nutrition, or Hypertrophy, is never known to affect the 

 whole body, to a degree sufficient to constitute disease. It cannot be produced 

 as a consequence of the ingestion of an undue supply of food ; for this does 

 not increase the formative activity of the tissues, but merely renders the blood 

 richer in nutritive materials ; a part of which the excreting organs are called 

 on to be continually removing, without its being rendered subservient to the 

 wants of the body ( 679) ; whilst another part may be employed in the nutri- 

 tion of one particular tissue, the Adipose, which has a tendency to increase 

 with the superfluity of non-azotized food, provided that the requisite amount 

 of cellular tissue be generated to hold the fatty matter ( 433). But examples 

 of Hypertrophy of particular tissues or organs are very common. Thus any 



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