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Human neurons are so small that they require a microscope in order to be seen. However, some neurons can be up to 3 feet long, such as those that extend from the spinal cord to the toes.
In 2006, a generic antinausea drug named ondansetron was approved. It is used to stop nausea and vomiting associated with surgery, chemotherapy, and radiation therapy.
People who have myopia, or nearsightedness, are not able to see objects at a distance but only up close. It occurs when the cornea is either curved too steeply, the eye is too long, or both. This condition is progressive and worsens with time. More than 100 million people in the United States are nearsighted, but only 20% of those are born with the condition. Diet, eye exercise, drug therapy, and corrective lenses can all help manage nearsightedness.
In 1835 it was discovered that a disease of silkworms known as muscardine could be transferred from one silkworm to another, and was caused by a fungus.
It is believed that humans initially contracted crabs from gorillas about 3 million years ago from either sleeping in gorilla nests or eating the apes.