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A.
The Number One Killer of American Women
Narrator:
This is Science Today. In the year 2000, among all
deaths of American women, thirty percent was attributed
to heart disease. Another nine percent of women
died of stroke, so cardiovascular disease as a whole
accounts for about forty percent of deaths among
women. Deborah Lindes, a professor of medicine at
the University of California, San Francisco, says
although heart disease is a huge problem for women,
it's not recognized as such. Instead, Lindes says
women are more concerned about breast cancer, which
in comparison, accounts for three percent of female
deaths in this country.
Lindes:
Cardiovascular disease is the number one killer of
women in the U.S. One in ten women in the middle-aged
years have heart disease and that goes up dramatically
as women age. One in four women over sixty-five have
some form of heart disease.
Narrator:
And yet,
Lindes says women with heart disease don't report
their symptoms as readily as men do, so they tend
to delay seeing a doctor until later in the course
of their disease.
Lindes:
Partly because women when they have symptoms, tend
to think that - well, this is probably not a heart
attack, I'm a woman isn't this a problem for men and
attribute their symptoms to other causes.
Narrator:
For Science Today, I'm Larissa Branin.
B.
Dispelling the Myth of a 'Rootless' Society
Narrator:
This is Science Today. There's a tendency to regard
today's society as being more on the move and less
rooted, geographically, than our great-grandparents
were. But historical records indicate the opposite.
Claude Fischer, a sociologist at the University of
California, Berkeley, says the major reason people
moved in the past was because of financial constraints.
Fischer:
Farm failed or there were too many people trying to
live off the same farm or factory closed down or somebody
got flooded out - or people just had economic hard
times. They would move from place to place - whether
it's from Europe to the United States or within the
United States.
Narrator:
But Fischer says a lot of those economic
pressures have eased as we've become a more affluent
and mobile society.
Fischer:
Back
in the 19th Century, when commuting meant walking
basically, if your new job was more than two miles
away, you probably would move. Today somebody can
change jobs, fifty miles may not make a difference
one way or the other, so it's easier to go from job
to job today if you stay in the same metropolitan
area and stay in the same neighborhood.
Narrator:
For Science Today, I'm Larissa Branin.
C.
How Menopausal Women Can Keep Their Estrogen Levels
Narrator:
This is Science Today. About two-thirds of women who
get breast cancer after menopause can trace the disease
to higher-than-normal levels of estrogen. Previous
studies have shown a close link between high levels
of estrogen and a higher risk for breast cancer. Dr.
Steven Cummings of the University of California at
San Francisco is trying to find ways to prevent the
onset of estrogen-related breast cancer. Some scientists
have recommended a low-fat diet.
Cummings:
Unfortunately, most studies have shown no benefit
to reducing fat unless you also reduce your weight.
Weight loss may reduce your risk so if you reduce
the fat level in your diet you may lose weight and
that may cause a reduction in your risk of breast
cancer.
Narrator:
Cummings says women should concentrate on keeping
their estrogen levels very low. Since higher estrogen
levels are found in heavier women, weight loss is
one possibility.
Cummings:
So, it can't be explained entirely by the effects
of hormones but it's one rational explanation-that
by losing weight you might reduce your estrogen level.
Narrator:
For Science Today, I'm Larissa Branin.
D.
An Asthma Study with Major Public Health Implications
Narrator:
This is Science Today. Since the late 1980s, rates
of asthma - especially in children - have been greatly
rising. Kathleen Mortimer, an epidemiologist at the
University of California, Berkeley has recently found
children born prematurely or of low birth weight,
are the most susceptible to smog-induced asthma.
Mortimer:
This was the first study that identified that
as a susceptible subgroup as far as I know. I mean,
there's been lots of evidence that in general, children
of low birth weight have more respiratory problems
throughout life and it lasts even until adulthood.
But this was the first one that looked particularly
at air pollution.
Narrator:
This study may have major public health implications
because this higher susceptibility doesn't just affect
asthmatic children….
Mortimer:
It may be that in the general population, children
who were born low birth weight or premature also show
this greater response and that has a bigger public
health impact because in general, only less than ten
percent of the population has asthma. But if worldwide
or nationwide, children even without asthma are greater
responders if they're premature, then it hits a bigger
population.
Narrator:
For Science Today, I'm Larissa Branin.
E.
Technology that Detects Tooth Decay in Early Stages
Narrator:
This is Science Today. The tools dentists most commonly
use to detect early tooth decay are the metal probe
and the x-ray. Daniel Fried of the University of California,
San Francisco's Department of Preventive and Restorative
Dental Sciences, says these procedures are effective,
but they don't detect decay in its earliest stages.
Fried:
What I mean by the very early stages is when it's
confined to the outer enamel layers because once it
penetrates down to the underlying dentin, the dentin
dissolves very fast and so the decay just blooms out
underneath the enamel. So it can cause what a dentist
would call hidden caries.
Narrator:
Fried and his colleagues are working on various types
of laser technologies to provide a tool that can detect
decay in these early stages.
Fried:
One of the tools that we're working on is called optical
coherence tomography. This is a tool that uses optical
fiber technology - so, it basically has a fiber probe
that you could stick into one of these pit and fissure
areas or scan across the surface of the tooth and
it measures changes in light scattering.
Narrator:
For
Science Today, I'm Larissa Branin.
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