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Did you know?

Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.

Did you know?

The horizontal fraction bar was introduced by the Arabs.

Did you know?

Over time, chronic hepatitis B virus and hepatitis C virus infections can progress to advanced liver disease, liver failure, and hepatocellular carcinoma. Unlike other forms, more than 80% of hepatitis C infections become chronic and lead to liver disease. When combined with hepatitis B, hepatitis C now accounts for 75% percent of all cases of liver disease around the world. Liver failure caused by hepatitis C is now leading cause of liver transplants in the United States.

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Patients who cannot swallow may receive nutrition via a parenteral route—usually, a catheter is inserted through the chest into a large vein going into the heart.

Did you know?

Not getting enough sleep can greatly weaken the immune system. Lack of sleep makes you more likely to catch a cold, or more difficult to fight off an infection.

Absorption of light energy by an electron Absorption of light energy by an electron
Phytochrome controls germination by responding to red/far red light signals. Phytochrome controls germination by responding to red/far red light signals.
Which wavelengths of light are most effective at photosynthesis? Which wavelengths of light are most effective at photosynthesis?
Supernova Light Curves Supernova Light Curves
Gravitational Redshift The color of light from the same object located at diffe Gravitational Redshift The color of light from the same object located at diffe
Endangerment sites of the head and face. Use only light to moderate pressure on head and face. Endangerment sites of the head and face. Use only light to moderate pressure on head and face.
Video: Origin of organelles Animation

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