With this test, tuberculin is injected between layers of the dermis.

在这个试验中，结核菌素注射于两层真皮之间。

Positive tuberculin test simply means that the patient's been exposed at some point to TB.

阳性结核菌素试验仅仅意味着患者曾暴露于TB。

Testing for TB often starts with a purified protein derivative or PPD intradermal skin test, sometimes known as a tuberculin skin test, Mantoux test or simply TB test.

为检测TB的存在，我们通常从纯蛋白衍生物（PPD）皮内试验开始，也称为结核菌素试验、芒图试验，或就简称为TB皮试。

And if a person has previously been exposed to TB, the immune system reacts to the tuberculin and produces a small localized reaction within 48 to 72 hours.

如果一个人曾经接触过TB，免疫系统就会对结核菌素发生反应，并且在48-72小时内产生局部反应。

As an alternative to tuberculin skin test, there are also interferon gamma release assays or IGRAs which look for evidence in the blood of previous exposure to TB proteins.

作为结核菌素试验的替代性试验，γ-干扰素体外释放试验分析技术（IGRA）是寻找在血液中曾经接触过TB蛋白的证据。