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Did you know?

In the ancient and medieval periods, dysentery killed about ? of all babies before they reach 12 months of age. The disease was transferred through contaminated drinking water, because there was no way to adequately dispose of sewage, which contaminated the water.

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Looking at the sun may not only cause headache and distort your vision temporarily, but it can also cause permanent eye damage. Any exposure to sunlight adds to the cumulative effects of ultraviolet (UV) radiation on your eyes. UV exposure has been linked to eye disorders such as macular degeneration, solar retinitis, and corneal dystrophies.

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Parkinson's disease is both chronic and progressive. This means that it persists over a long period of time and that its symptoms grow worse over time.

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The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.

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The Food and Drug Administration has approved Risperdal, an adult antipsychotic drug, for the symptomatic treatment of irritability in children and adolescents with autism. The approval is the first for the use of a drug to treat behaviors associated with autism in children. These behaviors are included under the general heading of irritability and include aggression, deliberate self-injury, and temper tantrums.

Periodic Table of the Elements Periodic Table of the Elements
Knead the calf muscles with both hands. Place the foot flat on the table, knee bent. Reach behind ... Knead the calf muscles with both hands. Place the foot flat on the table, knee bent. Reach behind ...
Pipeline markers are used to mark the location of underground pipelines containing hazardous ... Pipeline markers are used to mark the location of underground pipelines containing hazardous ...
Right Lateral View of Vertebral Column Right Lateral View of Vertebral Column
table table
table table
Video: New DNA Strand Replication

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