158 PHYSIOLOGY FOR DENTAL STUDENTS. 





The process of lymph absorption is rather slow except when it 

 is aided by the massage produced by the movements of the sur- 

 rounding parts. The rapid action of poisons, or drugs intro- 

 duced by a hypodermic syringe, is due to their absorption from 

 the intra-cellular or lymph spaces directly into the blood. Col- 

 ored solutions as india ink are absorbed by the lymphatics, and 

 by using a substance like this it is possible to trace the lymphat- 

 ics of a portion of the body. Micro-organisms, such as the strep- 

 tococcus, which causes one of the familiar forms of what is known 

 as blood poisoning, are taken up by the lymphatics, and it is 

 easy to trace the channels traversed by the organism by the in- 

 flamed lymphatic walls which appear as red lines under the skin. 

 Since all these vessels pass through a lymphatic gland on their 

 way to the subclavian vein, these glands are often very much 

 swollen, and may even be destroyed as the result of the infection. 

 It is probable that one of the functions of the lymph gland is to 

 catch and render non-toxic, poisons which are being carried into 

 the circulation by way of the lymphatics. One of the most 

 dreaded diseases, carcinoma, is carried by the lymphatic system 

 to other parts of the body. For this reason we most often see the 

 metastatic growths of cancer in the region of the lymph glands 

 which have caught the straying cancer cell and have been infect- 

 ed by it. 



The increased exudation of lymph in the tissues which occurs 

 in inflammatory conditions is no doubt of great advantage to the 

 tissues, since, by this means, a greater supply of nourishment is 

 provided for the repair of the damaged cells, and the defensive 

 substances (antibodies, etc.) are brought into play. 



