Bernardo Ramazzini, a 17th century occupational physician actually recognized the health hazards associated with prolonged sitting, especially among writers who developed fatigue in their upper extremities.

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They'll look for fatigue cracks often, especially with heavy traffic, especially trucks.

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Some common side effects, like nausea, dizziness or slight fatigue, are manageable--especially if the end result is pneumonia or tuberculosis, diseases that were once deadly but now can be treated with antibiotics.

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Caution is especially warranted in the market this year because prices have shown signs of fatigue since late 2011.

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They argue that Lyme, especially if left untreated, can spiral into a chronic condition characterized by neurological and fatigue symptoms.

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