SECTION SEVEN 



3. Wash for five to ten minutes in distilled water; blot and dry 

 in air. 



Results: 



Malaria parasites : chromatin, clear red; cytoplasm, clear blue. 



Treponema pallida. 



Solutions required: 



A. Giemsa stain. 



B. Sodium carbonate, A.R. 1% in 

 distilled water. 



Technique: 



1. A lesion is rubbed roughly until it bleeds, with a swab which 

 has been damped with absolute alcohol. 



2. While bleeding is taking place, swab the chancre at intervals. 

 After a few minutes a clear fluid exudate will appear from the 

 abraded surfaces. 



3. A drop of the clear fluid exudate (free from blood) is taken 

 from the periphery of the lesion with a platinum wire loop, trans- 

 ferred to a scrupulously clean slide, and spread into a film. 



4. Allow to dry in the air ; then fix in absolute alcohol for fifteen 

 minutes. 



5. Pour off any excess alcohol, and allow the last traces to 

 evaporate away in the air. 



6. Stain for fifteen to thirty minutes in a mixture consisting of 

 10 ml. distilled water buffered to 7-2, and 0-5 ml. Giemsa stain. 



7. Rinse in running tap water for a few seconds holding the 

 slide with the film facing downwards. 



8. Blot dry, and examine. 



Results: 



The spirochaetes are stained reddish violet. Nuclei of the leuco- 

 cytes reddish purple, while the rest of the leucocytes and pus cells 

 appear similar to Leishman-stained preparation. Cytoplasm of 

 Plasmodia, blue; chromatin, red. Erythrocytes, yellowish pink. 



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