MAST CELLS 



194 



MCILVAINE BUFFERS 



salicylic balsam or salicylic permount. 

 Spread a drop of saturated solution of 

 salicylic acid in toluol upon a cover 

 slip. Dry. The glass is then covered 

 with a thin crystalline layer of salicylic 

 acid. Put on it a drop of balsam or 

 permount and cover the section taken 

 out of the toluol (or xylol). Salicylic 

 acid instantaneously redissolves in the 

 mounting medium. This addition of 

 salicylic acid is not advantageous after 

 staining with anilin blue. 



Mast Cells, see Basophile Leucocytes and 

 Tissue Basophiles. 



Mastigophora, Techniques for given by Mc- 

 Clung, Microscopical Technique, 1950, 

 p. 469. 



Mastoid Process. Use methods for Bone. 

 Technique for measurements of size of 

 air cell system is given by Diamant, M., 

 Acta Radiol., 1940, 31, 543-548. 



Mauveine ((T, 846), a basic dj^e of light fast- 

 ness 3, the first dye made from aniline 

 in 1856. Gives stain of plant tissues 

 like Methyl violet (Emi_g, p. 57). 



Maximow (see Azure II Eosin Hematoxylin 

 method). He has advised as a fixative 

 90 cc. Zenker's fluid less acetic acid + 

 10 cc. formalin. This is essentially 

 Formalin Zenker. See Buzaglo's con- 

 nective tissue stain. 



May-Giemsa stain of Pappenheim (Folia 

 Haematol., Arch., 1917, 22, 15). This 

 is the same as Jenner-Giemsa. Fix 

 and stain air dried blood smears about 

 3 min. in May-Griinwald mixture (sat. 

 sol. methylene blue eosinate in methyl 

 alcohol). Add same amount aq. dest. 

 and leave 1 min. Pour off (but do not 

 wash) and add diluted Giemsa's solu- 

 tion. Stain in this 15-30 min. Rinse 

 aq. dest. 1 min. or until desired color 

 is reached. Blot dry. This is a good 

 modification of the ordinary Giemsa's 

 stain because it gives slightly more 

 intense colors. 



May-Griinwald combined fixative and stain 

 is a sat. sol. of methylene blue eosinate 

 in methyl alcohol (Grtibler or Holl- 

 born). If methylene blue eosinate is 

 not available make it as originally de- 

 scribed by Jenner (Lancet, 1899, No. 6, 

 370). Mix equal parts 1.25% water sol. 

 eosin and 1% methylene blue; after 24 

 hrs. filter; wash ppt. on filter_ with 

 water; dry and dissolve powder in 200 

 cc. pure methyl alcohol. It is employed 

 in the May-Giemsa and Kardos-Pap- 

 penheim methods for staining blood 

 smears. 

 May-Griinwald-Giemsa stain in one solu- 

 tion. Strumia (M. M., J. Lab. & Clin. 

 Med., 1935-36, 21, 930-934) gives di- 

 rections for combining the stains and 

 for use and notes that a standardized 

 product is prepared by Coleman and 



Bell Co. Intensity of coloration is 

 enhanced by the combination. 

 Mayer's Acid Alum Hematoxylin. The 



following formula is given by Mallory 

 (p. 73). Dissolve 1 gm. hematoxylin 

 in 1000 cc. aq. dest. with a little heat if 

 required. Add 0.2 gm. sodium iodate 

 and 50 gm. ammonium or potassium 

 alum. When latter is dissolved add 1 

 gm. citric acid and 50 gm. chloral hy- 

 drate. Color turns reddish violet. 

 Does not easily over-ripen. 



Mayer's Acid Carmine. The Bensleys 

 (p. 131) advise its preparation as 

 follows. Add 4 gm. carmine to 15 cc. 

 aq. dest. + 30 drops hydrochloric acid. 

 Boil until it is dissolved. Add 95 cc. 

 85% ethyl alcohol. Neutralize with 

 ammonia until the carmine begins to 

 precipitate as seen in a graduate against 

 white paper background. Add 4 more 

 drops ammonia after first precipitation. 

 If this acid carmine stains too quicklj^ 

 slow it down by dilution with 80-90% 

 alcohol. This gives a fine red nuclear 

 counterstain for tissues vitally stained 

 with Indigo-Carmine, Trypan Blue 

 and similar dyes. 



Mayer's Albumen, see Albumen Glycerin. 



Mcllvaine Buffers after Stitt from Lillie, 

 R. D., Stain Techn., 1941, 16, 1-6 who 

 employed them to improve Romanowsky 

 staining after various fixatives. See 

 Toluidine Blue Phloxinate Method, 

 (see Molecular Solution) To make 

 M/15 citric acid required dissolve 14.01 

 gm. mono-hydrateu crystalline citric 

 acid in 500 cc. aq. dest. and add enough 

 neutral methyl alcohol C.P. to make 

 total volume 1,000 cc. after careful 

 mixing. To make M/15 Na2HP04 dis- 

 solve 9.47 gm. anhydrous Na2HP04 

 in 500 cc. aq. dest. and make up to 

 1,000 cc. with methyl alcohol. These, 

 in following proportions listed in cc, 

 give pH values indicated. 



Since it is difficult to measure out these 



