Evidence shows that extended periods of cortisol in the body weakens bones, damages nerve cells in the brain and weakens the body's defense system against disease.

VOA: special.2009.03.24

For many years, researchers have studied why the space environment weakens bones.

VOA: special.2009.03.10

It weakens the body's natural defense system against disease.

VOA: special.2009.09.08

Alzheimers weakens or destroys memory and reasoning.

VOA: special.2010.03.09

Analysts say the biggest problem is high unemployment, which weakens demand and makes banks reluctant to lend.

VOA: standard.2009.12.20

In South Africa the virus, which weakens the immune system, is transmitted primarily through unsafe sex.

VOA: standard.2010.04.26

According to two men who are working to counter Islamic militants, the death of Noordin Top last week seriously weakens the country's terrorist network.

VOA: standard.2009.09.21