Twenty centres in the network are already doing an observational study on the patients who will be in the trial, to get a baseline from which to judge improvement from the therapy.

医疗网相关的二十个医疗中心已经对受试者进行了检测，以便于以后判断治疗的效果。

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Williams was trailing Clijsters 4-6, 5-6 and serving at 15-30 when the baseline judge called a foot-fault on a second serve.

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Those are obviously personal preferences but they will give you a baseline by which to judge the following.

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