现代细菌学研究的方法学始于19世纪晚期，包括建立细菌染色方法和在培养基中进行微生物分离的技术，当时的培养基是用明胶和琼脂固化的营养物质。

The modern methods of bacteriological technique began in the late 19th century with the use of stains and the development of methods of cultivating organisms on plates of nutrients.

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You've probably seen agar plates, if you smear a solution that's contaminated with bacteria on it, then that bacteria will grow on this agar rich medium and you'll get many, many copies of the bacteria that you've smeared at low density onto the plate.

你们大概见过琼脂培养基,如果将有细菌的溶液涂抹在培养基上,细菌就会在富含琼脂的培养基上生长,你会得到许多许多细菌,即使你只涂抹了低浓度溶液

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