While smell is still used as a secondary diagnostic tool in some illnesses, the lack of a reliable and objective analytical tool has prevented its wide spread usage in modern medicine.

虽然气味在一些疾病中仍然被用作次要的诊断手段，但是由于缺乏可靠和客观的分析工具，影响了它在现代医学中的广泛应用。

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After a while, he became aware that he could smell his hands burning.

VOA: special.2010.05.01

Radiation for example, is invisible, has no smell or odor, while it is extremely deadly for the humans.

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While many animals communicate using their sense of smell, it has long been assumed that humans lack this ability because we do not have the olfactory sensitivity of dogs for example.

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But anyone who has tried blending ice to make a smoothie will tell you that the process is loud, takes a while and usually leaves your blender emanating a strange burning smell.

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