这种设备仍处于试验阶段。

The equipment is still at the experimental stage.

《牛津词典》

然而，目前免疫疗法还处于试验阶段。

For the time being, however, immunotherapy is still in its experimental stages.

《柯林斯英汉双解大词典》

当他在自己身上试验还处于初级阶段的疫苗时，有些人说他的行为是莽撞的。

When he tested an early vaccine on himself, some described the act as foolhardy.

《柯林斯英汉双解大词典》

Another approach which is still investigational, in that it's being tried for many diseases but not yet clinically used in any particular one, is maybe you don't need to introduce a whole virus or pieces of a protein at all.

另一种方法目前仍处于试验阶段,该方法即将试用于许多疾病,但还没有对某一特定疾病进行临床试验,那就是无需引入整个病毒,或者根本不用引入蛋白质片段

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