中級 163 分類 收藏
開始影片後,點擊或框選字幕可以立即查詢單字
字庫載入中…
回報字幕錯誤
Hi this is David from MinuteEarth.
Throughout history, the biggest threat to humans has been physical harm either through
injury or infection.
So it's not surprising that our bodies have developed a bunch of internal systems that
respond once our external defenses have been breached.
One of those systems is led by a special enzyme called COX that lives in tissues throughout
our bodies.
When we get injured, the nearby COX makes a chemical that triggers the production of
lots of extra sticky platelets, which rush to stop the bleeding by clotting the wounds.
And when we get an infection, the nearby COX makes a different chemical that helps dilate
our blood vessels, so that a rush of fluid brings our tough immune cells to fight the
intruders.
But the world has changed; not only are pathogens and violence no longer our biggest threats,
but we also have other - sometimes better - ways to deal with them.
Our COX enzymes don't know that, though.
And in an ironic twist, we may be more likely to be harmed by our COX's response to perceived
threats than we are from the actual injuries and infections it's supposed to protect
us from.
That's because in the modern world, COX is often triggered into action unnecessarily,
and the ensuing response can have disastrous results.
For example, compared to our ancestors, modern humans - with our sedentary lifestyles and
fatty diets - are far more likely to build up cholesterol deposits in our blood vessels
- including the ones in our hearts and in our brains.
If one of the globs happens to break open, COX gets confused and initiates the same sticky
platelet response that it does when you actually rupture a blood vessel.
Except that this time the resulting clot can stop blood flow altogether.
If this happens near the heart, you get a heart attack.
And when this happens in the brain, the clot can cause a stroke.
And to make things even worse, those same sedentary lifestyles, fatty diets and other
modern behaviors seem to make our bodies think that we have infections in certain places
when we don't.
But COX helps flood our system with fluid and immune cells anyway.
And with no actual infection to fight, some of those excited immune cells start attacking
the body instead, which can result in autoimmune disease, depression, and even certain types
of cancers.
As a result, even as our chance of dying from injuries and infections has decreased, our
chances of dying from COX-related problems has actually increased.
We don't want to totally eliminate COX - we still want it around in case we do get a serious
injury or infection, and because it also helps protect our stomach lining.
But for certain parts of the population - like older folks with more cholesterol deposits
- it makes sense to deliberately lower COX's ability to react to any threats, real or perceived.
And it turns out that Aspirin - yep, that little pain pill in your cupboard - actually
ties up any COX it comes across, thus decreasing your chances of getting certain COX-related
problems.
Taking Aspirin regularly has some risks: by blocking COX, we're more prone to internal
bleeding and stomach ulcers.
But even so, studies show that when people over 50 with high risk of heart problems regularly
take low-dose Aspirin, they on average have reduced health care costs and longer lifespans.
For modern humans, it seems, one of the best ways to save lives is to deliberately stop
our bodies from trying to save their own lives.
This video was sponsored by the University of Minnesota, where students, faculty and
staff across all fields of study are working to solve the Grand Challenges facing society.
One of these challenges is advancing health through tailored solutions, which includes
improving our understanding of the risks and benefits of the COX enzyme.
Dr. Jeffrey Chipman, of the Department of Surgery, was part of the team that discovered
a second form of COX and changed its story.
And Dr. Russell Luepker leads the Minnesota Heart Health Program and its "Ask About Aspirin"
campaign.
Thanks University of Minnesota!
提示:點選文章或是影片下面的字幕單字,可以直接快速翻譯喔!

載入中…

How The Modern World Tricks Our Bodies Into Hurting Themselves

163 分類 收藏
林宜悉 發佈於 2019 年 11 月 10 日
看更多推薦影片
  1. 1. 單字查詢

    在字幕上選取單字即可即時查詢單字喔!

  2. 2. 單句重複播放

    可重複聽取一句單句,加強聽力!

  3. 3. 使用快速鍵

    使用影片快速鍵,讓學習更有效率!

  4. 4. 關閉語言字幕

    進階版練習可關閉字幕純聽英文哦!

  5. 5. 內嵌播放器

    可以將英文字幕學習播放器內嵌到部落格等地方喔

  6. 6. 展開播放器

    可隱藏右方全文及字典欄位,觀看影片更舒適!

  1. 英文聽力測驗

    挑戰字幕英文聽力測驗!

  1. 點擊展開筆記本讓你看的更舒服

  1. UrbanDictionary 俚語字典整合查詢。一般字典查詢不到你滿意的解譯,不妨使用「俚語字典」,或許會讓你有滿意的答案喔