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White blood cell

White blood cells (also called leukocytes or immune cells) are cells which form a component of the blood. They help to defend the body against infectious disease and foreign materials as part of the immune system. There are normally between 4x109 and 11x109 white blood cells in a litre of healthy adult blood - about 7,000 to 25,000 white blood cells per drop. In conditions such as leukaemia this may rise to as many as 50,000 white blood cells in a single drop of blood. As well as in the blood, white cells are also found in large numbers in the lymphatic system, the spleen, and in other body tissues.

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February 2, 2026

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Researchers studying nearly 2 million older adults found that cerebral amyloid angiopathy sharply raises the risk of developing dementia. Within five years, people with the condition were far more likely to be diagnosed than those without it. The ...
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Lowering salt in everyday foods could quietly save lives. Researchers found that modest sodium reductions in bread, packaged foods, and takeout meals could significantly reduce heart disease and stroke rates in France and the U.K. The key advantage ...
People who naturally stay up late may be putting their hearts under added strain as they age. A large study tracking more than 300,000 adults found that middle-aged and older night owls had poorer overall heart health and a higher risk of heart ...
Men start developing heart disease earlier than women, with risks rising faster beginning around age 35, according to long-term research. The difference is driven mainly by coronary heart disease, not stroke or heart failure. Traditional risk ...
A new drug developed by Australian researchers has shown promising results in reducing sepsis in a Phase II clinical trial involving 180 patients. The carbohydrate-based treatment works by calming a dangerous immune reaction that can cause organ ...

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