Stress is more likely to be harmful if you feel helpless to deal with the problem or situation that causes the stress.

VOA: special.2009.03.24

He says normally a protein in healthy immune cells causes the cells to die after they attack an invading virus or bacteria.

VOA: special.2010.05.19

Swaziland is said to have the highest known rate of infection for the virus that causes the disease.

VOA: special.2009.05.04

To move an arm, the brain sends a message that causes the chest muscles to tighten.

VOA: special.2009.03.10

Chronic stress causes the body to produce too much of two hormones, cortisol and adrenalin.

VOA: special.2010.10.12

Carbon dioxide is one of the gases that causes the warming of Earth's atmosphere.

VOA: special.2009.05.22

Warm air rising from below causes the wind tube to reach toward the ground.

VOA: special.2010.05.11

There is some debate about exactly what causes the brain to release endorphins.

VOA: special.2010.06.08

He discovered he had the virus that causes the disease AIDS.

VOA: special.2010.02.07

This causes the rock to break, or fracture,releasing the gas.

VOA: special.2009.10.23

The mucous causes the airways to close even more.

VOA: special.2009.07.28

This causes the tissues to die.

VOA: special.2010.08.09

The standard flu vaccine causes the body to produces antibodies, which target parts of the virus that frequently mutate.

VOA: standard.2010.07.21

Our inability to prevent weapons from being illegally smuggled across the border to arm these criminals causes the death of police officers, soldiers and civilians.

VOA: standard.2009.03.25