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Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.

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

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A recent study has found that following a diet rich in berries may slow down the aging process of the brain. This diet apparently helps to keep dopamine levels much higher than are seen in normal individuals who do not eat berries as a regular part of their diet as they enter their later years.

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Illicit drug use costs the United States approximately $181 billion every year.

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If all the neurons in the human body were lined up, they would stretch more than 600 miles.

The process of mitosis in an animal cell. The process of mitosis in an animal cell.
Comparison of the steps of two viral reproductive cycles. Comparison of the steps of two viral reproductive cycles.
A hypothetical model of the process of cell-wall expansion. A hypothetical model of the process of cell-wall expansion.
Process flow diagram for Acetic Anhydride Plant Process flow diagram for Acetic Anhydride Plant
The transition between steps usually occurs at a temperature that would not interfere with cold ... The transition between steps usually occurs at a temperature that would not interfere with cold ...
Wearing a pedometer, like the one shown here, can help you track your steps Wearing a pedometer, like the one shown here, can help you track your steps
Video: Cognitive development by Piaget (Preoperational stage or intelligence)

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