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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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Health & Medicine News
February 21, 2026
Feb. 21, 2026 Living at high altitude appears to protect against diabetes, and scientists have finally discovered the reason. When oxygen levels drop, red blood cells switch into a new metabolic mode and absorb large amounts of glucose from the blood. This helps ...
Feb. 21, 2026 Running extreme distances may strain more than just muscles and joints. New research suggests ultramarathons can alter red blood cells in ways that make them less flexible and more prone to breakdown, potentially interfering with how they deliver ...
Feb. 21, 2026 Researchers tested whether generative AI could handle complex medical datasets as well as human experts. In some cases, the AI matched or outperformed teams that had spent months building prediction models. By generating usable analytical code from ...
Feb. 21, 2026 A common bacterium best known for causing pneumonia and sinus infections may also play a surprising role in Alzheimer’s disease. Researchers found that Chlamydia pneumoniae can invade the retina and brain, where it sparks inflammation, nerve cell ...
Feb. 20, 2026 Exercise may sharpen the mind by repairing the brain’s protective shield. Researchers found that physical activity prompts the liver to release an enzyme that removes a harmful protein causing the blood-brain barrier to become leaky with age. In ...
Feb. 20, 2026 A groundbreaking clinical trial is testing whether specially engineered stem cells can help the brain restore its own dopamine production in people with Parkinson’s disease. Because the condition is driven by the gradual loss of dopamine-producing ...
Feb. 20, 2026 Breathing polluted air may do more than harm your lungs — it could also increase your risk of Alzheimer’s disease. In a sweeping study of nearly 28 million older Americans, researchers found that ...
Feb. 19, 2026 A sweeping new study has uncovered a troubling mix of hazardous chemicals in popular hair extensions, including products made from human hair. Researchers detected dozens of substances linked to cancer, hormone disruption, reproductive harm, and ...
Feb. 19, 2026 A new human study has uncovered how the body naturally turns off inflammation. Researchers found that fat-derived molecules called epoxy-oxylipins rein in immune cells that can otherwise drive chronic disease. Using a drug to boost these molecules ...
Feb. 19, 2026 A newly discovered bacterial duo may be the hidden cause of chronic constipation. The two microbes break down the colon’s protective mucus layer, leaving stool dry and hard — a problem traditional laxatives don’t fix. Parkinson’s patients, ...
Feb. 19, 2026 Myopia is skyrocketing around the world, often blamed on endless screen time — but new research suggests the real culprit may be something more subtle. Scientists at SUNY College of Optometry ...
Feb. 18, 2026 Northwestern researchers have shown that when it comes to cancer vaccines, arrangement can be just as important as ingredients. By repositioning a small fragment of an HPV protein on a DNA-based nanovaccine, the team dramatically strengthened the ...
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Feb. 18, 2026 Sugary drinks may be linked to more than just physical health problems in teens. A new review of multiple studies found a consistent association between high consumption of beverages like soda, ...
Feb. 18, 2026 Intermittent fasting has become one of the most talked-about weight loss trends in recent years, promising dramatic results with simple changes to when you eat. But a major Cochrane review suggests ...
Feb. 18, 2026 A major new study has spotlighted three familiar medicines that could take on an unexpected new role in the fight against Alzheimer’s disease — with a shingles vaccine emerging as the ...
Feb. 18, 2026 Antibiotic resistance is racing toward a global crisis, with “superbugs” projected to cause over 10 million deaths annually by 2050. Now, scientists at UC San Diego have unveiled a powerful new ...
Feb. 17, 2026 A new University at Buffalo study suggests cannabis-infused beverages could help some people cut back on alcohol. In a survey of cannabis users, those who drank cannabis beverages reported cutting ...
Feb. 17, 2026 Scientists in China have unveiled a breakthrough way to mass-produce powerful cancer-fighting immune cells in the lab. By engineering early-stage ...
Feb. 17, 2026 Researchers investigating crops grown in soil contaminated by the 2015 mining disaster in Brazil discovered that toxic metals are moving from the earth into edible plants. Bananas, cassava, and cocoa ...
Feb. 17, 2026 An Ice Age double burial in Italy has yielded a stunning genetic revelation. DNA from a mother and daughter who lived over 12,000 years ago shows that the younger had a rare inherited growth ...
Feb. 17, 2026 Researchers have identified two brain receptors that help the brain clear away amyloid beta, a hallmark of Alzheimer’s disease. By stimulating these receptors in mice, scientists increased levels ...
Feb. 17, 2026 A mysterious RNA found in breast cancer led scientists to uncover an entire hidden class of cancer-specific RNAs across dozens of tumor types. These molecules form unique molecular signatures that ...