Many diseases present with the same symptoms and signs, making them tricky to tell apart.

许多疾病都有相同的症状和体征，很难区分。

What's more, a single disease may have variable presentation, meaning that the symptoms and signs they cause vary from patient to patient.

此外，一种疾病可能有不同的表现，这意味着它们引起的症状和体征因人而异。

After recording the particular symptoms and signs from a patient, we're ready to make an educated guess as to why the patient might be ill.

在记录了病人的特殊症状和体征后，我们准备好对病人可能生病的原因进行有根据的猜测。

Hundreds of different diseases exist. Each has its own particular set of symptoms and signs, clues that enable a physician to diagnose the problem.

症状是病人自己就能觉察到的，比如，高烧、流血，或是疼痛。体征则是医生检测出的的，比如，血管扩张或是体内器官肿大。

Many diseases cause a variety of effects and involve more than one body system. A characteristic group of symptoms and signs that accompanies a disease is called a syndrome.

通常，医生使用实验室检查来帮助确定诊断。一般的诊断方法包括影像学，血液检查和组织活检。