Diabetes

Routine blood tests could predict diabetes

Random plasma glucose tests could be used to predict which patients will develop diabetes, according to a study of Veterans Affairs treatment data. Researchers from several VA systems showed that levels of glucose found during ...

Cardiology

New approach to reducing damage after a heart attack

Researchers in the Medical Sciences Division have established a key cause of micro blood vessels constricting during surgery to reopen a blocked artery, and identified a potential therapeutic target to block the mechanism ...

Cardiology

Hypertension poorly managed in low- and middle-income countries

Health systems in low- and middle-income countries (LMICs) are poorly prepared for the increasing number of people with high blood pressure, with more than two-thirds of people affected going without treatment, according ...

Surgery

A better avenue for neurosurgery to improve outcomes

For years cardiologists have threaded hair-like surgical instruments through arteries in the wrist, as an access point to perform procedures on the heart. For procedures in the brain, however, neurosurgeons more commonly ...

Medical research

Antimicrobial protein implicated in Parkinson's disease

An immune system protein that usually protects the body from pathogens is abnormally produced in the brain during Parkinson's disease, scientists from Sanford Burnham Prebys report. The discovery, published in Free Radical ...

Diabetes

Diabetes medications masking surgical complication

A new class of diabetes medications is masking the potentially dangerous condition of ketoacidosis at the time of surgery. Testing for acid load in the blood of diabetes sufferers who are taking gliflozin medications is needed ...

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Blood

Blood is a specialized bodily fluid that delivers necessary substances to the body's cells — such as nutrients and oxygen — and transports waste products away from those same cells.

In vertebrates, it is composed of blood cells suspended in a liquid called blood plasma. Plasma, which comprises 55% of blood fluid, is mostly water (90% by volume), and contains dissolved proteins, glucose, mineral ions, hormones, carbon dioxide (plasma being the main medium for excretory product transportation), platelets and blood cells themselves. The blood cells present in blood are mainly red blood cells (also called RBCs or erythrocytes) and white blood cells, including leukocytes and platelets. The most abundant cells in vertebrate blood are red blood cells. These contain hemoglobin, an iron-containing protein, which facilitates transportation of oxygen by reversibly binding to this respiratory gas and greatly increasing its solubility in blood. In contrast, carbon dioxide is almost entirely transported extracellularly dissolved in plasma as bicarbonate ion.

Vertebrate blood is bright-red when its hemoglobin is oxygenated. Some animals, such as crustaceans and mollusks, use hemocyanin to carry oxygen, instead of hemoglobin. Insects and some molluscs use a fluid called hemolymph instead of blood, the difference being that hemolymph is not contained in a closed circulatory system. In most insects, this "blood" does not contain oxygen-carrying molecules such as hemoglobin because their bodies are small enough for their tracheal system to suffice for supplying oxygen.

Jawed vertebrates have an adaptive immune system, based largely on white blood cells. White blood cells help to resist infections and parasites. Platelets are important in the clotting of blood. Arthropods, using hemolymph, have hemocytes as part of their immune system.

Blood is circulated around the body through blood vessels by the pumping action of the heart. In animals having lungs, arterial blood carries oxygen from inhaled air to the tissues of the body, and venous blood carries carbon dioxide, a waste product of metabolism produced by cells, from the tissues to the lungs to be exhaled.

Medical terms related to blood often begin with hemo- or hemato- (also spelled haemo- and haemato-) from the Ancient Greek word αἶμα (haima) for "blood". In terms of anatomy and histology, blood is considered a specialized form of connective tissue, given its origin in the bones and the presence of potential molecular fibers in the form of fibrinogen.

This text uses material from Wikipedia, licensed under CC BY-SA