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		HEPES-buffered Modified Steinberg's Solution (HBSt) (Zackson & Steinberg, 1986, Dev. Biol. 117: 342-353) NaCl 58.0 mM 3.40 g KCl 0.67 mM 0.0500 g CaCl2. 2H2O 0.34 mM 0.0500 g MgSO4. 7H2O 1.0 mM 0.250 g HEPES 1.10 g dH2O to 1 liter Adjust to pH 7.4 with NaOH or HCl Add 140 ml of a 50 mg/ml Gentamycin stock solution to 100 ml 100% HBSt for Operating Solution (70 mg/ml final concentration). Sterile with 0.2 mm filter.
		Operating dishes Operate in 60 mm dishes coated with 1% agarose in 1X HBSt (add 1-2% powdered charcoal for contrast for albino embryos). Right before use heat a glass rod and use to melt several small depressions in the agarose to help confine embryos during surgery.