It was proved by tests that it can stain a lot of the samples each time. It can stains the samples quickly and have them well distributed.

实验证明，利用该装置一次可以染色较多的样品，而且能使样品的染色均匀、快速。

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Attempts to carry out scientific tests on the semen stain on Mrs Gregson's clothing in 1977, 1988 and 1995 had proved unsuccessful.

BBC: DNA catches killer 23 years on