TRANSPLANTATION OF TISSUES 



"45 



grafts succeed (Marine and Manley) . It is not as yet known what 

 the circumstances are which so modify the usual adverse condi- 

 tions that a homceograft can take, grow and permanently survive. 



Fig. 487. Suturing Bloodvessels: Preliminary Fixation of Ends of Divided Vessels 

 (after Guthrie). Three fixing ligatures arc placed at equidistant points on the 

 circumference of the cut ends, each ligature being passed through corresponding 

 points of the two vessels. The ends of the vessels are approximated by drawing 

 on the ligatures, which are then tied, and the margins of the vessels sewed together 

 by continuous stitches in the intervals between the fixing ligatures, as in Fig. 488. 

 (Carrel's method). 



But there is reason to believe that the solution of this problem would 

 be a long step towards answering the immensely important practical 

 question what the conditions are which permit the development 

 of malignant tumours. 



Fig. 488. Suturing Bloodvessels: Method of approximating Ldges aid putting in 

 Continuous Suture (after Guthrie). The needles are very hut ca ubric sewing- 

 needles, and the threads single strands of Chinese twist silk or human hair. 

 Needles and threads are sterilized in paraffin-oil. (Method of Carrel and Guthrie. ) 



Transplantation of organs may also be done with anastomosis oi 

 bloodvessels. The main vessels of the engrafted organ are sutured 

 to suitable arteries and veins in the ' host,' so that the circulation 

 is at once effective. Consequently there is practically no limit to 

 the size of the grafts. The kidney, spleen, and even a limb, have 



