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Only one in 10 cancer deaths is caused by the primary tumor. The vast majority of cancer mortality is caused by cells breaking away from the main tumor and metastasizing to other parts of the body, such as the brain, bones, or liver.

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Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.

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According to the National Institute of Environmental Health Sciences, lung disease is the third leading killer in the United States, responsible for one in seven deaths. It is the leading cause of death among infants under the age of one year.

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Certain topical medications such as clotrimazole and betamethasone are not approved for use in children younger than 12 years of age. They must be used very cautiously, as directed by a doctor, to treat any child. Children have a much greater response to topical steroid medications.

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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.

(a) Initial mtDNA results suggested modern humans and Neadertals were equally distantly related to D (a) Initial mtDNA results suggested modern humans and Neadertals were equally distantly related to D
Fossil remains of anatomically modern humans from the Czech Republic and from China (center crania) Fossil remains of anatomically modern humans from the Czech Republic and from China (center crania)
How Axis Tilt Affects the Intensity of Solar Radiation How Axis Tilt Affects the Intensity of Solar Radiation
Radiation Radiation
Earth emits radiation back out to space from all surfaces, both day and night Earth emits radiation back out to space from all surfaces, both day and night
Chart showing average yearly dose of radiation from natural and human-made sources Chart showing average yearly dose of radiation from natural and human-made sources
Video: DNA Replication

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