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Did you know?

Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.

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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.

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Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.

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Every flu season is different, and even healthy people can get extremely sick from the flu, as well as spread it to others. The flu season can begin as early as October and last as late as May. Every person over six months of age should get an annual flu vaccine. The vaccine cannot cause you to get influenza, but in some seasons, may not be completely able to prevent you from acquiring influenza due to changes in causative viruses. The viruses in the flu shot are killed—there is no way they can give you the flu. Minor side effects include soreness, redness, or swelling where the shot was given. It is possible to develop a slight fever, and body aches, but these are simply signs that the body is responding to the vaccine and making itself ready to fight off the influenza virus should you come in contact with it.

Did you know?

Most women experience menopause in their 50s. However, in 1994, an Italian woman gave birth to a baby boy when she was 61 years old.

The vocal cords within the larynx, superior view from the pharynx. The vocal cords within the larynx, superior view from the pharynx.
The major skeletal muscles—anterior superficial view. The major skeletal muscles—anterior superficial view.
Worldwide Variations in Population and Income Levels Worldwide Variations in Population and Income Levels
Levels of Anxiety Levels of Anxiety
Aerial View of the Ruins Of PompeII Aerial View of the Ruins Of PompeII
Artist’s depiction of the view inside the uterus, showing a fetus connected by an umbilical cord ... Artist’s depiction of the view inside the uterus, showing a fetus connected by an umbilical cord ...
Video: Medullary osmotic gradient - influencing factors

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