Researchers have been looking for the cause or causes of attention deficit hyperactivity disorder.

VOA: special.2009.09.29

The tension of stress can interfere with sleep or cause anger or sadness.

VOA: special.2009.03.24

Such medicines may produce headaches or cause them to worsen, the Clinic says.

VOA: special.2010.03.30

Aviation analysts say the sharp volcanic particles can damage a jet engine or cause it to shut down in mid air.

VOA: standard.2010.04.15

We can start now to focus our attention on the real cause or causes of autism.

VOA: standard.2010.03.23

Too much time inside the house using a computer or watching television can cause someone to get cabin fever.

VOA: special.2010.03.28

Clots can block the flow of blood to the heart or brain and cause a heart attack or stroke.

VOA: special.2009.10.20

Studies support the theory that there are several causes, instead of a single environmental cause or genetic problem.

VOA: special.2009.01.06

And any argument between us would not cause me to lose heart or feel a sense of loss.

VOA: special.2010.07.11

But a drop in oxygen levels can cause a health emergency in people with heart or lung problems.

VOA: special.2009.07.14

They say their findings show that even low levels of smoke may cause behavior problems in children with asthma or others at risk.

VOA: special.2009.01.13

If hoarseness continues or the cause is unknown, doctors should perform an examination called a laryngoscopy.

VOA: special.2009.09.02

Or,they said, it would cause freed slaves to move north and take away jobs from whites.

VOA: special.2009.10.08

Any new heat or fire could cause the leaking well and the surrounding area to explode.

VOA: special.2009.03.22