Oncology & Cancer

A promising new treatment for recurrent pediatric brain cancer

Two pediatric brain cancers that are challenging to treat if they recur, medulloblastoma and ependymoma, are the target of a clinical trial using a new type of therapy. A multi-institutional, international team led by researchers ...

Medical research

Schistosomiasis research: New hope for a neglected disease

It's a disease that's hard to pronounce and even harder to eradicate, but schistosomiasis is worth the effort. Caused by parasitic worms carried by freshwater snails, schistosomiasis leads to about 280,000 deaths each year, ...

Oncology & Cancer

Tracking tumor cells and unraveling hidden information

tumor cells circulating in the blood of cancer patients are important markers for early diagnosis, treatment success and patient prognosis. But since so few circulate, identifying them is a challenge. Thanks to artificial ...

Medical research

Targeting cancers' surroundings to prevent or limit metastasis

Cancer depends on blood. Just like the rest of the body, tumors need blood vessels to supply them with nutrients and oxygen to grow. But cancer uses these vessels in another way as well—to spread to other parts of the body.

Psychology & Psychiatry

Imbalance between serotonin and dopamine in social anxiety disorder

The balance between the neurotransmitters serotonin and dopamine may affect whether a person develops social anxiety disorder. Previous research has mainly focused on either the serotonin or the dopamine system individually. ...

Oncology & Cancer

New drug limits cancer spreading

A research team that recently invented a drug to stop blood vessels from forming a treatment resistant barrier around some cancers has now discovered the drug can be used to prevent the cancer from spreading.

Ophthalmology

New cell models for ocular drug discovery

Researchers at the University of Eastern Finland have developed two new cell models that can open up new avenues for ocular drug discovery. The new cell models are continuously growing retinal pigment epithelial cells, which ...

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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