SECTION SEVEN 



C. Papanicolaou stain, powder . . 07 gm. 



Alcohol 95% . . . . . . 100 ml. 



Place in a flask, plug the neck lightly with 

 cotton- wool; then heat, on a waterbath until 

 dissolved. Cool, then filter. 



Technique: 



1 . Wet smears are fixed in a mixture of equal volumes of ether 

 and absolute alcohol for five to fifteen minutes. • 



2. Rinse successively in 90%, 70% and 50% alcohols and dis- 

 tilled water. 



3. Stain in Ehrlich's haematoxylin for five to ten minutes. 



4. Rinse in distilled water; differentiate in 0-5% hydrochloric 

 acid. 



5. Rinse in distilled water; then leave for one minute in dilute 

 lithium carbonate solution (three drops saturated lithium carbon- 

 ate to 100 ml. distilled water). 



6. Rinse thoroughly in distilled water and wash successively in 



50%, 70%, 95% alcohol. 



7. Stain for one minute in Orange G solution (prepared as 

 above). 



8. Rinse thoroughly in 95% alcohol to remove all excess stain. 



9. Stain for two minutes in Papanicolaou stain; then rinse five 

 to ten times in each of three jars of 95% alcohol. 



10. Rinse in absolute alcohol; clear in xylol and mount. 



Results: 



Nuclei, red. Erythrocytes, orange. Cornified cells, red, pink 

 or orange. Basophile cells, blue or green. 



PEROXroASE REACTION (Cowdry's method) 



For blood films 



Solutions required: 



A. Copper sulphate crystals . . 0*5 gm. 



Distilled water . . . . . . 100 ml. 



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