★英語聽力頻道為大家整理的在線英語聽力材料：麻醉功效，供大家參考。更多閱讀請查看本站英語聽力頻道。
如果你曾經動過手術，你可能會記得躺下和醒來這兩個動作，但是對中間發(fā)生的事情一無所知。
If you've ever had major surgery, you probably remember lying down and waking up–but nothing inbetween.
多虧了你的麻醉師，在實際的手術過程中你對疼痛全然不知。
Thanks to the anesthesiologist, during the actual surgery you were out of it: immobilized andinsensitive to pain.
但直到最近科學家們對麻醉藥如何在細胞水平上發(fā)揮作用仍然了解甚少。
But until recently scientists had little understanding of how anesthetics actually work on the cellular level.
歸功于瑞士蘇黎世大學研究人員的最新研究，這種情況得以改變。
That's changed thanks to recent experiments performed by researchers at the University of Zurich, in Switzerland.
他們知道正如許多藥物那樣，麻醉藥讓大腦里的疼痛受體處于關閉狀態(tài)。
They knew that anesthetics caused pain receptors in the brain to turn off by acting likemost drugs do:
麻醉藥依附在神經細胞里的特定區(qū)域，并對它們進行麻醉。
麻醉功效.jpg
anesthetizing drugs attach to particular sites on nerve cells and turn them off.
問題是，這些藥物是依附在神經細胞的的哪個部位呢？
Thequestion was, where on nerve cells do these drugs attach?
神經細胞膜針對大腦產生的各種化學物質都有受體。
Nerve cell membranes have receptors for different kinds of chemicals produced by the brain.
如γ-氨基丁酸或伽馬氨基丁酸，都是可以使神經細胞關閉的化學物質。
Gamma-amino butyric acid, or GABA, for example, is a chemical thatshuts down nerve cells.
假設全身麻醉與神經細胞上的伽馬氨基丁酸受體有關，那么可以激活受體，指示細胞關閉。
The hypothesis was that general anesthesia works by binding to GABAreceptors on a nerve cell, thereby activating the receptor and instructing the cell to shut down.
因此蘇黎世大學研究人員認為應該著重研究伽馬氨基丁酸受體。
So itmade sense for the Zurich researchers to focus on GABA receptors.
為了此項研究，研究人員們用經過遺傳工程處理后的老鼠做實驗，這些老鼠的伽馬氨基丁酸受體不會對麻醉藥起反應。
To do this they worked with mice that had been genetically engineered to have nerve cells with GABA receptors that wouldn't respond to anesthetics.
果然，這些老鼠在注射了麻醉藥后并不像正常的老鼠注射了麻醉藥那樣，對疼痛免疫。
And sure enough, when such mice were givenanesthetic drugs they weren't nearly as immune to pain as regular mice that had also been given pain-blocking drugs.
顯然，在神經細胞上的伽馬氨基丁酸受體就是麻醉藥發(fā)揮作用的地方。
Clearly, GABA receptor sites on nerve cells are part of what allows anesthetics to dotheir job.
盡管蘇黎世大學的實驗只解決了謎團中的一小部分，但是研究麻醉藥是怎樣工作的以及怎樣讓它們工作的更好仍是非常重要的。
While the Zurich experiment fills in only one piece of the puzzle, it is an important step towards learning how these amazing drugs work, and how to make them even better.
如果你曾經動過手術，你可能會記得躺下和醒來這兩個動作，但是對中間發(fā)生的事情一無所知。
If you've ever had major surgery, you probably remember lying down and waking up–but nothing inbetween.
多虧了你的麻醉師，在實際的手術過程中你對疼痛全然不知。
Thanks to the anesthesiologist, during the actual surgery you were out of it: immobilized andinsensitive to pain.
但直到最近科學家們對麻醉藥如何在細胞水平上發(fā)揮作用仍然了解甚少。
But until recently scientists had little understanding of how anesthetics actually work on the cellular level.
歸功于瑞士蘇黎世大學研究人員的最新研究，這種情況得以改變。
That's changed thanks to recent experiments performed by researchers at the University of Zurich, in Switzerland.
他們知道正如許多藥物那樣，麻醉藥讓大腦里的疼痛受體處于關閉狀態(tài)。
They knew that anesthetics caused pain receptors in the brain to turn off by acting likemost drugs do:
麻醉藥依附在神經細胞里的特定區(qū)域，并對它們進行麻醉。
麻醉功效.jpg
anesthetizing drugs attach to particular sites on nerve cells and turn them off.
問題是，這些藥物是依附在神經細胞的的哪個部位呢？
Thequestion was, where on nerve cells do these drugs attach?
神經細胞膜針對大腦產生的各種化學物質都有受體。
Nerve cell membranes have receptors for different kinds of chemicals produced by the brain.
如γ-氨基丁酸或伽馬氨基丁酸，都是可以使神經細胞關閉的化學物質。
Gamma-amino butyric acid, or GABA, for example, is a chemical thatshuts down nerve cells.
假設全身麻醉與神經細胞上的伽馬氨基丁酸受體有關，那么可以激活受體，指示細胞關閉。
The hypothesis was that general anesthesia works by binding to GABAreceptors on a nerve cell, thereby activating the receptor and instructing the cell to shut down.
因此蘇黎世大學研究人員認為應該著重研究伽馬氨基丁酸受體。
So itmade sense for the Zurich researchers to focus on GABA receptors.
為了此項研究，研究人員們用經過遺傳工程處理后的老鼠做實驗，這些老鼠的伽馬氨基丁酸受體不會對麻醉藥起反應。
To do this they worked with mice that had been genetically engineered to have nerve cells with GABA receptors that wouldn't respond to anesthetics.
果然，這些老鼠在注射了麻醉藥后并不像正常的老鼠注射了麻醉藥那樣，對疼痛免疫。
And sure enough, when such mice were givenanesthetic drugs they weren't nearly as immune to pain as regular mice that had also been given pain-blocking drugs.
顯然，在神經細胞上的伽馬氨基丁酸受體就是麻醉藥發(fā)揮作用的地方。
Clearly, GABA receptor sites on nerve cells are part of what allows anesthetics to dotheir job.
盡管蘇黎世大學的實驗只解決了謎團中的一小部分，但是研究麻醉藥是怎樣工作的以及怎樣讓它們工作的更好仍是非常重要的。
While the Zurich experiment fills in only one piece of the puzzle, it is an important step towards learning how these amazing drugs work, and how to make them even better.