SECTION SIX 



B. Haematoxylin . . . . . . i gm. 



Ethyl alcohol 95% . . . . . . 100 ml. 



C. Ferric chloride hydrated 50% 

 aqueous . . . . . . • • 5 "nl* 



Distilled water . . . . . . 95 ml. 



D. Solution B . . . . . . . . i volume 



Solution C . . . . . . . . I volume 



Mix well, and allow to stand for two or three 

 weeks before use. Filter immediately be- 

 fore use. 



Note: The fresh solution must not he used as it darkens the emulsion 

 gelatine ; 60 ml. of this solution is sufficient for about twenty radio- 

 autographs. 



E. Acetone and Xylol, equal volumes 



Technique: 



1. Surgical and post-mortem specimens from patients having 

 recently received radioiodine (P^^) and tissues from laboratory 

 animals to which radioiodine, radiosulphur (S^^) or radiophos- 

 phorus (P22) has been administered, are fixed in Bouin's fluid. 



2. Embed in paraffin wax, using the Dioxan technique. 



3. Cut sections 7 to lo/x in thickness. 



4. Transfer the section ribbons to the darkroom, place in a 

 waterbath, and float them onto a photographic plate. (X-ray film, 

 Kodak Medium lantern slides or Kodak nuclear track plates, are 

 suitable for this purpose.) 



5. Allow the sections to dry on the plate, when they will 

 become permanently attached to the photographic emulsion. 



Note: For each isotype the processing fluids should be examined 

 by a Geiger counter to ensure that there is no significant loss of the 

 radioactive material from the tissue. 



6. After proper photographic exposure, removal of the paraffin 

 wax, development, fixation, washing and drying, the autograph is 

 stained as follows: 



7. Stain with metanil yellow (solution A) for five to fifteen 

 seconds. 



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