In the family of disorders known as hemophilia, a patient can usually complete the first two steps of hemostasis just fine, but they can't make an effective fibrin clot.

在被称为友病的疾病家族中，病人通常可以很好地完成止的前两个步，他们不能制造有效的纤维蛋白块。

To prevent complications from an existing blood or bleeding disorder, such as sickle cell disease, thalassemia, or anaemia caused by kidney disease, haemophilia, or von Willebrand disease.

预防现有液或出性疾病的并发症，如镰状细胞病、地中海贫或由肾脏疾病、友病或管性友病引起的贫。

This is because the process called hemostasis, literally meaning to stop the flow of blood, is impaired.

这为友病患者的止过程受损，即其功能出现障碍。

Treatment for hemophilia A and B are done with injections of the missing or nonfunctional clotting factor.

治疗友病A和B的方法通常注射那些缺失或失活的子。

Signs and symptoms hemophilia A and B are nearly clinically identical, which makes sense since factors VIIIa and IXa work together in the coagulation cascade to activate factor X.

友病A和B的体征和症状在临床上几乎相同，也说得通，为子VIIIa和IXa在级联反应中，共同作用以激活子X。

Diagnosis of hemophilia A and B usually starts with lab tests including a platelet count which is usually normal, a prothrombin (PT) time, and a partial thromboplastic (PTT) time.

友病A和B的诊断通常进行实验检测，包括小板计数（一般正常）、酶原时间（PT），以及部分活酶时间（PTT）。

By far the most common of these are deficiencies of factor VIII which gives rise to factor VIIIa and is stabilized by another factor called von Willebrand factor.

目前为止，大多数的友病通常子VIII缺乏症；子VIII能转变为子VIIIa，并被管性友病子（vWF）固定。

Believe it or not, this is a somewhat simplified version of the coagulation cascade; but, it contains all of the key parts needed to understand hemophilia.

总之，这就简化版的级联反应，已经包含了理解友病病理所需的关键部分。

And also how he knows exactly that he's a hemophiliac.

还有他如何确切知道自己友病患者的。

Okay, so a form of hemophilia that is passed down, and it unfortunately takes, I believe, both parents to pass it on.

好的， 这一种遗传性友病，不幸的， 据我所知，需要父母双方共同遗传给孩子。

For people suffering from haemophilia at the time, even with the best doctors in the world, the disease could be fatal.

对于当时患有友病的人来说，即使有世界上最顶尖的医生，这种疾病也可能致命的。