Did you know?

The horizontal fraction bar was introduced by the Arabs.

Did you know?

Asthma attacks and symptoms usually get started by specific triggers (such as viruses, allergies, gases, and air particles). You should talk to your doctor about these triggers and find ways to avoid or get rid of them.

Did you know?

Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.

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Prostaglandins were first isolated from human semen in Sweden in the 1930s. They were so named because the researcher thought that they came from the prostate gland. In fact, prostaglandins exist and are synthesized in almost every cell of the body.

Did you know?

Ether was used widely for surgeries but became less popular because of its flammability and its tendency to cause vomiting. In England, it was quickly replaced by chloroform, but this agent caused many deaths and lost popularity.

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