《那些古怪又讓人憂心的問題》第50期:消失的DNA(3)
The frightening thing about Amanita poisoning is the “walking ghost” phase-the period where you seem to be fine (or getting better), but your cells are accumulating irreversible and lethal damage.
This pattern is typical of DNA damage, and we'd likely see something like it in someone who lost their DNA.
這是典型的DNA損傷症狀，從中我們可以一窺丟失所有DNA的人的悲慘後果。The picture is even more vividly illustrated by two other examples of DNA damage: chemotherapy and radiation.
如果再看看化療和放療這兩種DNA損害的例子，你就會有更真實的認識。
Radiation and chemotherapy
放療和化療Chemotherapy drugs are blunt instruments. Some are more precisely targeted than others, but many simply interrupt cell division in general. The reason that this selectively kills cancer cells, instead of harming the patient and the cancer equally, is that cancer cells are dividing all the time, whereas most normal cells divide only occasionally.
化療藥物非常粗暴。雖然一些藥物的靶向性比其他一些藥物要好，但許多藥物就是粗暴地干擾一切細胞分裂。這種藥物能夠選擇性地殺死癌細胞，而不是給病人和癌細胞以相同傷害的原因在於，癌細胞每時每刻都在分裂，而絕大多數正常的細胞都只是間歇性地分裂。Some human cells do divide constantly. The most rapidly dividing cells are found in the bone marrow, the factory that produces blood.
一些人體細胞確實會時常分裂。分裂最頻繁的細胞位於骨髓這個人體造血工廠內。Bone marrow is also central to the human immune system. Without it, we lose the ability to produce white blood cells, and our immune system collapses. Chemotherapy causes damage to the immune system, which makes cancer patients vulnerable to stray infections.
骨髓對於人類免疫系統也是至關重要。沒有了骨髓，我們就失去了製造白細胞的能力，我們的免疫系統也會隨之崩潰。化療會對免疫系統造成損害，使得癌症病人無法抵禦遊離感染。There are other types of rapidly dividing cells in the body. Our hair follicles and stomach lining also divide constantly, which is why chemotherapy can cause hair loss and nausea.
我們體內還有其他幾種頻繁分裂的細胞。我們頭髮的發囊和胃黏膜都在持續分裂，這也是爲什麼化療會造成脫髮和噁心。Doxorubicin, one of the most common and potent chemotherapy drugs, works by linking random segments of DNA to one another to tangle them. This is like dripping superglue on a ball of yarn; it binds the DNA into a useless initial side effects of doxorubicin, in the few days after treatment, are nausea, vomiting, and diarrhea-which makes sense, since the drug kills cells in the digestive tract.
阿黴素是最常用也是最強力的化療藥物之一，它可以隨機把DNA不同片段連接到一起，纏住它們，這就像你往一個毛線球上滴超級膠水一樣，它能把DNA粘成無用的一團。阿黴素在使用幾天後就會表現出早期副作用，包括噁心、嘔吐以及腹瀉，這也不難理解，因爲這種藥物殺死了消化道中的細胞。A loss of DNA would cause similar cell death, and probably similar symptoms.
全身DNA丟失也會類似地造成細胞死亡，症狀也很有可能和上面說的相似。
