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Hemolytic Streptococcus Toxins and Antitoxins
[摘要] The medium and method described here for the preparation of streptococcus toxin has been employed by us since October, 1931. The medium is a modification of the one used for some time for diphtheria toxin production. The streptococcus medium differs chiefly in that Pfanstiehl or Witte peptone has been substituted for Difco Proteose peptone, and it contains dextrose. The adjustment of the reaction during the growth period is considered essential.Method.1. (a) Fresh veal (leg) infusion. One part meat in 2 parts water by weight. Care should be taken to have the meat as free as possible of fat and connective tissue.2. (b) Refrigerate overnight.3. (c) Place in double boiler—raise temperature very slowly to 80°C. (Should require between four and five hours.)4. (d) Filter through one layer of cheesecloth. (Let drain, do not press.)5. (e) Weigh and make up to the original weight of the water and meat, minus the weight of the cooked meat.6. (f) Let stand five or ten minutes to settle, and then syphon off the supernatant.
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[效力级别]  [学科分类] 生物科学(综合)
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