The body's natural defenses presumably can destroy low levels of exposure.

But, while Europe s defenses have been considerably strengthened, the threat of terrorism has not diminished.

The presence of Spain's enemies in the Straits prompted the Spanish king Philip IV to order Gibraltar's defences to be strengthened.

As a result, governments now probe one another s defenses every day, increasing the risk of accidental hostilities.

Banks defenses need to be fortified during excessive upswings in asset prices so that they are able to weather the inevitable reversals.

In 1973, Dimona s defenders downed a wayward Libyan civilian airliner heading for the reactor, killing 108 people.

It was not until 1309 when Gibraltar's defences were put to the test for the first time in the First Siege of Gibraltar.

Fitting with an immunological explanation, the inflammatory process is caused by T cells, a kind of lymphocyte that plays an important role in the body's defenses.

The second project, that comprises space based ballistic missile defences, requires a very large scale constellation of assets in space to be effective.

Expressing concern that the development of missile defences could impact negatively on nuclear disarmament and non proliferation and lead to a new arms race on earth and in outer space,

Russian officials intimate that the US is using the threat of a North Korean or Iranian attack on the US with nuclear armed ballistic missiles as a pretext to erect defenses against Russia (and probably China).

Expressing concern that the development of missile defences could impact negatively on nuclear disarmament and non proliferation and lead to a new arms race on earth and in outer space,

During 19 April, the fourth day, the 1st Belorussian Front broke through the final line of the Seelow Heights and nothing but broken German formations lay between them and Berlin.

The idea was that Russia would protect NATO from attacking missiles traveling over its territory, with the expectation that the alliance would then forego developing defenses capable of engaging missiles over Russia.

This enabled the town to grow as a seaport but the need for additional defences was shown when it was attacked by Welsh forces in 1187 and again in 1260 by Llewelyn the Great.

Moreover, Sharon now agreed that a security fence, which historically was favored by the Israeli left, would enhance Israel s defenses.

By the end of the day there was no prospect that the German defence of the city could do anything but temporarily delay the capture of the city by the Soviets, as the decisive stages of the battle had already been fought and lost by the Germans outside the city.

In the early days of the crisis, it was argued that, given the strength of the regime s air defenses and ground forces, even these limited objectives could not be achieved without fighting an all out war and thus causing a net increase in human suffering.