Richard Weller: Could the sun be good for your heart?

88,013 views ・ 2013-01-17

TED


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00:00
Translator: Morton Bast Reviewer: Thu-Huong Ha
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Prevoditelj: Maja Budišin Lukin Recezent: Mladen Barešić
00:15
So, before I became a dermatologist,
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Prije no što sam postao dermatolog,
00:18
I started in general medicine,
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započeo sam se baviti općom medicinom,
00:20
as most dermatologists do in Britain.
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poput većine dermatologa u Britaniji.
00:22
At the end of that time, I went off to Australia,
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Na kraju tog razdoblja, otišao sam u Australiju.
00:24
about 20 years ago.
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Prije 20-ak godina.
00:26
What you learn when you go to Australia
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U Australiji naučite
00:28
is the Australians are very competitive.
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da su Australci vrlo kompetitivni.
00:31
And they are not magnanimous in victory.
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I nisu velikodušni u pobjedi.
00:33
And that happened a lot:
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Puno se puta to događalo...
00:35
"You pommies, you can't play cricket, rugby."
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"Vi, dotepenci britanski, ne znate igrati kriket, ragbi..."
00:38
I could accept that.
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To sam mogao prihvatiti.
00:40
But moving into work --
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Ali... prijeđimo na posao...
00:42
and we have each week what's called a journal club,
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Svakog tjedna okupljamo se u tzv. znanstvenom klubu,
00:45
when you'd sit down with the other doctors
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gdje mi, liječnici, međusobno razgovaramo
00:47
and you'd study a scientific paper
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i proučavamo znanstvene radove
00:49
in relation to medicine.
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iz medicinskog područja.
00:51
And after week one, it was about cardiovascular mortality,
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Drugog tjedna... Tema je bila smrtnost od kardiovaskularnih bolesti.
00:54
a dry subject -- how many people die of heart disease,
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Suhoparno područje! Koliko ljudi umire od srčanih bolesti,
00:57
what the rates are.
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kolike su stope smrtnosti...?
00:59
And they were competitive about this:
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I u tome su bili natjecateljski raspoloženi...
01:01
"You pommies, your rates of heart disease are shocking."
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"Vi, dotepenci britanski, vaše stope srčanih bolesti su šokantne!
01:04
And of course, they were right.
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I, naravno, bili su u pravu.
01:06
Australians have about a third less heart disease than we do --
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Australci imaju oko trećinu manje srčanih bolesti od nas.
01:10
less deaths from heart attacks, heart failure, less strokes --
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Manje smrtnih slučajeva od srčanog udara, zatajenja srca, manje moždanih udara...
01:14
they're generally a healthier bunch.
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Općenito su zdravija družina.
01:16
And of course they said this was because of
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I, naravno, rekli su da je to zbog
01:17
their fine moral standing, their exercise,
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njihovih visokih moralnih gledišta, njihovog vježbanja,
01:19
because they're Australians and we're weedy pommies, and so on.
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jer oni su Australci, a mi smo pripiti britanski dotepenci,...
01:24
But it's not just Australia that has better health than Britain.
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Ali, nije Australija jedina zemlja u kojoj su ljudi boljeg zdravlja od Britanaca.
01:29
Within Britain, there is a gradient of health --
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U Velikoj Britaniji, koristimo se tzv. gradijentom zdravlja -
01:32
and this is what's called standardized mortality,
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to je ono što se naziva standardiziranom stopom smrtnosti -
01:34
basically your chances of dying.
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u osnovi, vjerojatnost da ćete umrijeti.
01:36
This is looking at data from the paper about 20 years ago,
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Ovo su podaci iz istraživanja od prije 20-ak godina,
01:39
but it's true today.
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ali vrijede i danas.
01:41
Comparing your rates of dying 50 degrees north --
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Uspoređujući stope umiranja na 50 stupnjeva sjeverne zemljopisne širine -
01:44
that's the South, that's London and places --
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to je jug... London, i obližnja mjesta -
01:46
by latitude, and 55 degrees --
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s onima na 55 stupnjeva...
01:50
the bad news is that's here, Glasgow.
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Loša vijest je da je to ovdje - Glasgow.
01:52
I'm from Edinburgh. Worse news, that's even Edinburgh.
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Ja sam iz Edinburgha. Još gora vijest - to je čak i Edinburgh.
01:55
(Laughter)
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(Smijeh)
01:59
So what accounts for this horrible space here
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Kako objasniti ovu strašnu razliku
02:02
between us up here in southern Scotland
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između nas ovdje gore, na jugu Škotske,
02:04
and the South?
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i ljudi na jugu Engleske?
02:05
Now, we know about smoking,
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O pušenju sve znamo,
02:07
deep-fried Mars bars, chips -- the Glasgow diet.
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o prženim čokoladicama, čipsu, prehrani u Glasgowu....
02:10
All of these things.
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O svim tim stvarima.
02:11
But this graph is after taking into account
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Ali, ovaj prikaz uzima u obzir
02:14
all of these known risk factors.
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sve te poznate rizične čimbenike:
02:16
This is after accounting for smoking, social class, diet,
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i pušenje, i društvenu klasu, prehranu,
02:20
all those other known risk factors.
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i sve ostale poznate rizične čimbenike.
02:21
We are left with this missing space
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No, nedostaje nam i dalje razlog
02:24
of increased deaths the further north you go.
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povećane smrtnosti što dalje idemo prema sjeveru.
02:27
Now, sunlight, of course, comes into this.
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Naravno, ne zaboravimo na Sunčevu svjetlost...
02:30
And vitamin D has had a great deal of press,
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O vitaminu D je u tisku bilo puno govora,
02:32
and a lot of people get concerned about it.
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i zainteresirano je mnogo ljudi.
02:34
And we need vitamin D. It's now a requirement that children have a certain amount.
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Nama je vitamin D potreban! Danas ga djeca moraju imati u određenoj količini.
02:38
My grandmother grew up in Glasgow,
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Moja je baka odrasla u Glasgowu,
02:41
back in the 1920s and '30s when rickets was a real problem
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1920-ih i 30-ih kada je rahitis bio istinski problem,
02:44
and cod liver oil was brought in.
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i kad je u liječenje uvedeno bakalarevo jetreno ulje.
02:46
And that really prevented the rickets that used to be common in this city.
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To je doista zaustavilo rahitis, dotad uobičajen u ovom gradu.
02:50
And I as a child was fed cod liver oil by my grandmother.
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I mene je moja baka u djetinjstvu hranila bakalarevim jetrenim uljem.
02:54
I distinctly -- nobody forgets cod liver oil.
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Jako se dobro sjećam... nitko ne zaboravlja bakalarevo jetreno ulje!
02:57
But an association: The higher people's blood levels of vitamin D are,
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Jedna asocijacija: što je viša razina vitamina D u krvi,
03:02
the less heart disease they have, the less cancer.
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rjeđe su srčane bolesti, rjeđi je rak.
03:05
There seems to be a lot of data suggesting that vitamin D is very good for you.
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Čini se da dosta podataka ukazuje da je vitamin D vrlo dobar za sve nas.
03:09
And it is, to prevent rickets and so on.
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I jest, za sprečavanje rahitisa i sličnih bolesti...
03:11
But if you give people vitamin D supplements,
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No, prepisujete li ljudima dodatke vitaminu D,
03:14
you don't change that high rate of heart disease.
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ne smanjujete tu visoku stopu srčanih bolesti.
03:18
And the evidence for it preventing cancers is not yet great.
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I dokazi da oni sprečavaju nastanak raka još uvijek nisu uvjerljivi.
03:21
So what I'm going to suggest is that vitamin D is not the only story in town.
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Zato bih naglasio da vitamin D nije jedino o čemu vrijedi govoriti.
03:26
It's not the only reason preventing heart disease.
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On nije jedino što sprečava pojavu srčanih bolesti.
03:30
High vitamin D levels, I think, are a marker for sunlight exposure,
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Smatram da je visoka razina vitamina D pokazatelj izlaganja suncu,
03:34
and sunlight exposure, in methods I'm going to show,
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a izlaganje suncu, u postupcima koje ću prikazati,
03:37
is good for heart disease.
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blagotvorno je za srčane bolesti.
03:40
Anyway, I came back from Australia,
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Kako god, vrativši se iz Australije,
03:42
and despite the obvious risks to my health, I moved to Aberdeen.
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i unatoč očitim rizicima za moje zdravlje, preselio sam se u Aberdeen.
03:45
(Laughter)
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(Smijeh)
03:48
Now, in Aberdeen, I started my dermatology training.
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U Aberdeenu sam započeo s dermatološkom izobrazbom.
03:51
But I also became interested in research,
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Međutim, zainteresirao sam se i za istraživanje,
03:53
and in particular I became interested in this substance, nitric oxide.
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i to osobito dušikovog oksida.
03:56
Now these three guys up here,
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Ova trojica ovdje,
03:57
Furchgott, Ignarro and Murad,
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Furchgott, Ignarro i Murad,
03:59
won the Nobel Prize for medicine back in 1998.
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osvojila su Nobelovu nagradu za medicinu 1998.
04:02
And they were the first people to describe
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Oni su bili prvi koji su opisali
04:04
this new chemical transmitter, nitric oxide.
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ovaj novi kemijski prijenosnik - dušikov oksid.
04:08
What nitric oxide does is it dilates blood vessels,
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Dušikov oksid proširuje krvne žile
04:11
so it lowers your blood pressure.
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snižavajući tako krvni tlak.
04:12
It also dilates the coronary arteries, so it stops angina.
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Proširuje i srčane arterije, onemogućavajući tako anginu.
04:17
And what was remarkable about it
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S time u vezi,
04:18
was in the past when we think of chemical messengers within the body,
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značajno je da smo nekoć, sjetimo li se kemijskih glasnika u tijelu,
04:22
we thought of complicated things like estrogen and insulin,
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razmišljali o kompleksnim stvarima poput estrogena i inzulina,
04:25
or nerve transmission.
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ili o živčanom prijenosu.
04:27
Very complex processes with very complex chemicals
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Vrlo složeni procesi, s vrlo složenim kemikalijama,
04:30
that fit into very complex receptors.
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što se uklapaju u vrlo složene receptore.
04:32
And here's this incredibly simple molecule,
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A ovdje je ta nevjerojatno jednostavna molekula,
04:35
a nitrogen and an oxygen that are stuck together,
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spoj dušika i kisika,
04:38
and yet these are hugely important for [unclear] our low blood pressure,
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no iznimno važna za snižavanje krvnog tlaka,
04:43
for neurotransmission, for many, many things,
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za prijenos živčanih impulsa, za mnogo toga...
04:45
but particularly cardiovascular health.
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Naročito za zdravlje krvožilnog sustava!
04:49
And I started doing research, and we found, very excitingly,
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Započeo sam s istraživanjima, i otkrili smo - vrlo uzbudljivo! -
04:52
that the skin produces nitric oxide.
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da koža proizvodi dušikov oksid.
04:55
So it's not just in the cardiovascular system it arises.
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Dakle, ne pojavljuje se on samo u krvožilnom sustavu...
04:57
It arises in the skin.
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Pojavljuje se u koži.
04:59
Well, having found that and published that,
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Pošto smo to otkrili i objavili otkriće,
05:01
I thought, well, what's it doing?
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pomislio sam: Dobro, a na što on utječe?
05:03
How do you have low blood pressure in your skin?
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Kako postići nizak krvni tlak u koži?
05:05
It's not the heart. What do you do?
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Ne radi se o srcu. Što učiniti?
05:07
So I went off to the States, as many people do if they're going to do research,
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Otišao sam u SAD, kao i mnogi ljudi koji se kane baviti istraživanjima,
05:11
and I spent a few years in Pittsburgh. This is Pittsburgh.
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i proveo sam nekoliko godina u Pittsburghu. Ovo je Pittsburgh.
05:15
And I was interested in these really complex systems.
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Zanimali su me ovi doista složeni sustavi.
05:17
We thought that maybe nitric oxide affected cell death,
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Pomislili smo da dušikov oksid možda utječe na umiranje stanica,
05:21
and how cells survive, and their resistance to other things.
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i na preživljavanje stanica, i na njihovu otpornost na razne tvari.
05:24
And I first off started work in cell culture, growing cells,
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Započeo sam raditi na staničnoj kulturi, na uzgoju stanica...
05:27
and then I was using knockout mouse models --
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Potom sam koristio mišje "knockout" modele -
05:29
mice that couldn't make the gene.
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miševe koji nisu mogli stvoriti gen...
05:31
We worked out a mechanism, which -- NO was helping cells survive.
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Otkrili smo mehanizam prema kojemu dušikov oksid pomaže stanicama preživjeti.
05:35
And I then moved back to Edinburgh.
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Onda sam se vratio u Edinburgh...
05:39
And in Edinburgh, the experimental animal we use is the medical student.
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A u Edinburghu, kao "laboratorijskog miša" koristimo - studenta medicine.
05:42
It's a species close to human,
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To je vrsta bliska ljudskoj,
05:44
with several advantages over mice:
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s nekoliko prednosti u odnosu na miševe:
05:46
They're free, you don't shave them, they feed themselves,
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besplatni su, nije ih potrebno brijati, sami se hrane,
05:49
and nobody pickets your office saying,
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i nitko ne upada u vaš ured uz riječi:
05:51
"Save the lab medical student."
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"Zaštitimo laboratorijskog studenta medicine!"
05:54
So they're really an ideal model.
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Dakle, oni su stvarno idealni predlošci.
05:57
But what we found
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Međutim, otkrili smo da
05:59
was that we couldn't reproduce in man the data we had shown in mice.
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na čovjeku ne možemo ponoviti nalaze koje smo dobili na miševima.
06:04
It seemed we couldn't turn off the production
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Čini se da nismo mogli isključiti proizvodnju
06:07
of nitric oxide in the skin of humans.
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dušikovog oksida u koži ljudi.
06:10
We put on creams that blocked the enzyme that made it,
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Stavljali smo kreme koje onemogućavaju enzim koji ga stvara,
06:13
we injected things. We couldn't turn off the nitric oxide.
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ubrizgavali smo koješta. Nismo mogli isključiti dušikov oksid.
06:17
And the reason for this, it turned out, after two or three years' work,
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Nakon dvije ili tri godine rada, ispostavilo se
06:20
was that in the skin we have huge stores
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da u koži imamo ogromne zalihe -
06:25
not of nitric oxide, because nitric oxide is a gas,
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ne dušikovog oksida, jer on je plin,
06:28
and it's released -- (Poof!) -- and in a few seconds it's away,
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i pušten... puf!... nema ga za par sekundi,
06:31
but it can be turned into these forms of nitric oxide --
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ali može se pretvoriti u oblike dušikovog oksida:
06:34
nitrate, NO3; nitrite, NO2; nitrosothiols.
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nitrate (NO3), nitrite (NO2), nitrozotiole.
06:38
And these are more stable,
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Oni su stabilniji.
06:39
and your skin has got really large stores of NO.
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U našoj koži postoje uistinu velike zalihe dušikovog oksida.
06:43
And we then thought to ourselves, with those big stores,
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Kad su već zalihe tolike, pitali smo se
06:46
I wonder if sunlight might activate those stores
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može li ih Sunčeva svjetlost aktivirati
06:49
and release them from the skin,
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i otpustiti ih iz kože
06:51
where the stores are about 10 times as big as what's in the circulation.
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u kojoj su one i 10-ak puta veće od onih u krvotoku.
06:54
Could the sun activate those stores into the circulation,
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Može li Sunce te zalihe potaknuti ka krvotoku,
06:57
and there in the circulation do its good things for your cardiovascular system?
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i tako blagotvorno djelovati na krvožilni sustav?
07:03
Well, I'm an experimental dermatologist,
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Kako sam ja eksperimentalni dermatolog,
07:05
so what we did was we thought
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pomislili smo da ćemo
07:06
we'd have to expose our experimental animals to sunlight.
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morati naše "pokusne kuniće" izlagati suncu.
07:10
And so what we did was we took a bunch of volunteers
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Uzeli smo stoga hrpu dobrovoljaca
07:14
and we exposed them to ultraviolet light.
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i izlagali ih ultraljubičastom svjetlu.
07:17
So these are kind of sunlamps.
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To su, znači, svojevrsne solarne svjetiljke.
07:18
Now, what we were careful to do was,
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Pritom smo vodili računa o tome
07:21
vitamin D is made by ultraviolet B rays
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da ultraljubičaste B-zrake potiču stvaranje vitamina D,
07:24
and we wanted to separate our story from the vitamin D story.
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a ovaj smo svoj rad željeli odvojiti od teme vitamina D.
07:28
So we used ultraviolet A, which doesn't make vitamin D.
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Zato smo upotrebljavali ultraljubičaste A-zrake koje ne stvaraju vitamin D.
07:32
When we put people under a lamp
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Kad smo ljude izložili zrakama svjetiljke
07:34
for the equivalent of about 30 minutes of sunshine in summer in Edinburgh,
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onoliko koliko je istovjetno 30-minutnom ljetnom sunčanju u Edinburghu,
07:39
what we produced was, we produced a rise
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izazvali smo porast
07:42
in circulating nitric oxide.
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dušikovog oksida u krvi.
07:44
So we put patients with these subjects under the UV,
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Onda smo uključili i pacijente i njih izlagali ultraljubičastim zrakama;
07:47
and their NO levels do go up,
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količine dušikovog oksida su i kod njih rasle,
07:49
and their blood pressure goes down.
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a krvni tlak je padao.
07:51
Not by much, as an individual level,
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Na individualnoj razini ne suviše,
07:54
but enough at a population level
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ali na razini populacije dovoljno
07:56
to shift the rates of heart disease in a whole population.
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da utječe na učestalost srčanih bolesti u cijeloj populaciji.
08:00
And when we shone UV at them,
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Kad smo ih obasjavali ultraljubičastim zrakama,
08:02
or when we warmed them up to the same level as the lamps,
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ili kad smo ih zagrijavali do temperature svjetiljki,
08:06
but didn't actually let the rays hit the skin, this didn't happen.
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ali smo onemogućili kontakt zraka i kože, to se nije dogodilo.
08:09
So this seems to be a feature of ultraviolet rays hitting the skin.
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Dakle, čini se da samo sraz ultraljubičastih zraka i kože dovodi do takvog učinka.
08:13
Now, we're still collecting data.
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Naravno, još prikupljamo podatke.
08:15
A few good things here:
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Nekoliko je dobrih vijesti...
08:16
This appeared to be more marked in older people.
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Čini se da je to izraženije kod starijih ljudi.
08:19
I'm not sure exactly how much.
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Nisam siguran točno koliko.
08:21
One of the subjects here was my mother-in-law,
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Jedna od ispitanika bila je i moja punica,
08:23
and clearly I do not know her age.
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i, očito, ja ne znam koliko joj je godina.
08:26
But certainly in people older than my wife,
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Ali, sigurno kod osoba starijih od moje supruge
08:29
this appears to be a more marked effect.
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učinak se čini izrazitijim.
08:32
And the other thing I should mention
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Moram napomenuti da
08:33
was there was no change in vitamin D.
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nije bilo promjene u razini vitamina D.
08:36
This is separate from vitamin D.
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Ovo nema veze s vitaminom D.
08:38
So vitamin D is good for you -- it stops rickets,
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Dakle, vitamin D je dobar za vas - zaustavlja rahitis,
08:39
it prevents calcium metabolism, important stuff.
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sprečava razgradnju kalcija, važnog elementa.
08:41
But this is a separate mechanism from vitamin D.
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No, ovdje se radi o procesu različitom od onoga kod vitamina D.
08:44
Now, one of the problems with looking at blood pressure
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Jedan od problema s krvnim tlakom je
08:47
is your body does everything it can
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što tijelo čini sve što može
08:49
to keep your blood pressure at the same place.
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da bi ga održalo.
08:50
If your leg is chopped off and you lose blood,
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Ostanemo li bez noge i gubimo krv,
08:52
your body will clamp down, increase the heart rate,
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tijelo će pooštriti kontrolu, ubrzati rad srca,
08:55
do everything it can to keep your blood pressure up.
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učiniti sve što može kako bi održalo naš krvni tlak.
08:57
That is an absolutely fundamental physiological principle.
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To je apsolutno temeljno fiziološko načelo.
09:00
So what we've next done
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Potom smo proučavali
09:02
is we've moved on to looking at blood vessel dilatation.
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širenje krvnih žila.
09:05
So we've measured -- this is again,
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Mjerili smo... ovo je ponovno...
09:07
notice no tail and hairless, this is a medical student.
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vidite ćelavoga i bez repa, studenta medicine.
09:12
In the arm, you can measure blood flow in the arm
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Protok krvi u ruci moguće je izmjeriti
09:15
by how much it swells up as some blood flows into it.
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po tome koliko ruka nabrekne uslijed dotoka krvi.
09:18
And what we've shown is that doing a sham irradiation --
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Pokazali smo da lažno ozračivanje -
09:22
this is the thick line here --
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to je ova debela crta ovdje -
09:23
this is shining UV on the arm so it warms up
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ovo je ultraljubičasto ozračivanje ruke, kojime ju se zagrijava,
09:25
but keeping it covered so the rays don't hit the skin.
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ali zrake ne dopiru do kože, jer je pokrivena.
09:28
There is no change in blood flow, in dilatation of the blood vessels.
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Nema promjena u protoku krvi, niti u širenju krvnih žila.
09:32
But the active irradiation,
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Međutim, pri aktivnom ozračivanju
09:34
during the UV and for an hour after it,
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ultraljubičastim zrakama i sat vremena nakon njega,
09:37
there is dilation of the blood vessels.
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vidljivo je proširivanje krvnih žila.
09:39
This is the mechanism by which you lower blood pressure,
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Na ovaj se način može sniziti krvni tlak,
09:42
by which you dilate the coronary arteries also,
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čime se proširuju i srčane arterije,
09:44
to let the blood be supplied with the heart.
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što srcu olakšava potiskivanje krvi u tijelo.
09:46
So here, further data that ultraviolet -- that's sunlight --
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Ovo je daljnja potvrda da ultraljubičaste zrake, tj. Sunčeva svjetlost,
09:51
has benefits on the blood flow and the cardiovascular system.
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imaju blagotvoran učinak na protok krvi i na krvožilni sustav.
09:55
So we thought we'd just kind of model --
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Odlučili smo uobličiti u model
09:58
Different amounts of UV hit different parts of the Earth at different times of year,
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različite količine UV-zračenja, na različitim dijelovima Zemlje, u različita doba godine.
10:04
so you can actually work out those stores of nitric oxide --
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Tako je moguće izračunati zalihe dušikovog oksida -
10:08
the nitrates, nitrites, nitrosothiols in the skin --
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nitrate, nitrite, nitrozotiole u koži -
10:10
cleave to release NO.
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koji cijepanjem oslobađaju dušikov oksid.
10:13
Different wavelengths of light have different activities of doing that.
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Različite svjetlosne valne duljine imaju pritom različite uloge.
10:17
So you can look at the wavelengths of light that do that.
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Stoga možemo promatrati koje svjetlosne valne duljine što čine.
10:19
And you can look -- So, if you live on the equator, the sun comes straight overhead,
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Dakle, ako živimo na ekvatoru, Sunce je točno iznad naših glava;
10:23
it comes through a very thin bit of atmosphere.
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probija se kroz vrlo tanak sloj atmosfere.
10:25
In winter or summer, it's the same amount of light.
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I zimi i ljeti, to je ista količina svjetla.
10:27
If you live up here, in summer
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Živimo li ovdje,
10:30
the sun is coming fairly directly down,
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ljeti sunce pada prilično izravno,
10:32
but in winter it's coming through a huge amount of atmosphere,
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ali zimi se probija kroz ogromne slojeve atmosfere,
10:36
and much of the ultraviolet is weeded out,
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i mnogo se ultraljubičastih zraka gubi,
10:39
and the range of wavelengths that hit the Earth
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a raspon valnih duljina koje dolaze do Zemlje
10:41
are different from summer to winter.
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se od ljeta do zime razlikuje.
10:44
So what you can do is you can multiply those data
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Dakle, možemo pomnožiti te podatke
10:46
by the NO that's released
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s oslobođenim dušikovim oksidom
10:48
and you can calculate how much nitric oxide
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i izračunati koliko će dušikovog oksida
10:51
would be released from the skin into the circulation.
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biti iz kože otpušteno u krvotok.
10:54
Now, if you're on the equator here --
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Nalazimo li se na ekvatoru -
10:56
that's these two lines here, the red line and the purple line --
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to su ove dvije crte ovdje, crvena i ljubičasta -
10:59
the amount of nitric oxide that's released is the area under the curve,
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količina oslobođenog dušikovog oksida odgovara površini ispod krivulje,
11:04
it's the area in this space here.
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površini u ovom području ovdje.
11:06
So if you're on the equator, December or June,
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Dakle, nađemo li se na ekvatoru, u prosincu ili u lipnju,
11:08
you've got masses of NO being released from the skin.
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koža će otpuštati gomile dušikovog oksida.
11:12
So Ventura is in southern California.
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Ventura se nalazi u južnoj Kaliforniji.
11:14
In summer, you might as well be at the equator.
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Ljeti bi nam jednako bilo i na ekvatoru.
11:16
It's great. Lots of NO is released.
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Sjajno je ondje! Oslobađaju se ogromne količine dušikovog oksida.
11:18
Ventura mid-winter, well, there's still a decent amount.
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Ventura usred zime? Još je uvijek zamjetna pristojna količina.
11:22
Edinburgh in summer, the area beneath the curve is pretty good,
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Edinburgh ljeti? Površina ispod krivulje je zadovoljavajuća.
11:26
but Edinburgh in winter, the amount of NO that can be released
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Ali, Edinburgh zimi? Količina oslobođenog dušikovog oksida
11:31
is next to nothing, tiny amounts.
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gotovo je nikakva, neznatna.
11:34
So what do we think?
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Dakle, što mi mislimo?
11:36
We're still working at this story,
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Još uvijek na ovome radimo,
11:38
we're still developing it, we're still expanding it.
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još uvijek razvijamo model, proširujemo ga.
11:40
We think it's very important.
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Smatramo ovo vrlo važnim!
11:41
We think it probably accounts for a lot of the north-south health divide within Britain,
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Ovo vjerojatno uvelike objašnjava zdravstvene razlike između britanskog sjevera i juga.
11:45
It's of relevance to us.
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Ovo je i za nas važno!
11:47
We think that the skin --
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Mislimo da koža...
11:48
well, we know that the skin has got very large stores
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Dobro, znamo da koža sadrži vrlo velike zalihe
11:51
of nitric oxide as these various other forms.
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dušikovog oksida u svim tim različitim drugim oblicima.
11:53
We suspect a lot of these come from diet,
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Pretpostavljamo da je za mnoge zaslužna prehrana -
11:55
green leafy vegetables, beetroot, lettuce
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zeleno lisnato povrće, cikla ili zelena salata
11:58
has a lot of these nitric oxides that we think go to the skin.
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bogati su dušikovim oksidima za koje vjerujemo da odlaze u kožu.
12:01
We think they're then stored in the skin,
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Potom se pohranjuju u koži,
12:03
and we think the sunlight releases this
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i mislimo da ih Sunčeva svjetlost oslobađa
12:05
where it has generally beneficial effects.
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što, općenito, ima korisne učinke.
12:08
And this is ongoing work, but dermatologists --
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Puno je još posla pred nama, ali dermatolozi...
12:11
I mean, I'm a dermatologist.
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Želim reći, ja sam dermatolog.
12:12
My day job is saying to people, "You've got skin cancer,
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Moj svakodnevni posao je govoriti ljudima: "Imate rak kože;
12:15
it's caused by sunlight, don't go in the sun."
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uzrokovan je suncem; ne izlazite na sunce..."
12:17
I actually think a far more important message
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A mislim da je, zapravo, daleko važnija poruka
12:19
is that there are benefits as well as risks to sunlight.
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da se u sunčevoj svjetlosti kriju i blagodati, kao i opasnosti.
12:23
Yes, sunlight is the major alterable risk factor for skin cancer,
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Da, Sunčeva svjetlost je glavni promjenljiv rizični uzročnik raka kože,
12:29
but deaths from heart disease are a hundred times higher
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ali smrtnost oboljelih od srčanih bolesti stoput je veća
12:31
than deaths from skin cancer.
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od smrtnosti uslijed raka kože.
12:33
And I think that we need to be more aware of,
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Mislim da moramo biti oprezniji,
12:36
and we need to find the risk-benefit ratio.
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i da trebamo naći pravu mjeru opasnosti i blagodati.
12:38
How much sunlight is safe,
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Koliko se smijemo izlagati suncu,
12:40
and how can we finesse this best for our general health?
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i kako ga možemo najbolje iskoristiti za svoje zdravlje?
12:44
So, thank you very much indeed.
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Hvala vam najljepša, doista!
12:46
(Applause)
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(Pljesak)
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