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The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.

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Chronic marijuana use can damage the white blood cells and reduce the immune system's ability to respond to disease by as much as 40%. Without a strong immune system, the body is vulnerable to all kinds of degenerative and infectious diseases.

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The shortest mature adult human of whom there is independent evidence was Gul Mohammed in India. In 1990, he was measured in New Delhi and stood 22.5 inches tall.

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More than one-third of adult Americans are obese. Diseases that kill the largest number of people annually, such as heart disease, cancer, diabetes, stroke, and hypertension, can be attributed to diet.

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About 3.2 billion people, nearly half the world population, are at risk for malaria. In 2015, there are about 214 million malaria cases and an estimated 438,000 malaria deaths.

A comparison of monophyletic, paraphyletic, and polyphyletic taxonomic groups. A comparison of monophyletic, paraphyletic, and polyphyletic taxonomic groups.
A soil surface crust that includes nitrogen-fixing, soil-enriching cyanobacteria. A soil surface crust that includes nitrogen-fixing, soil-enriching cyanobacteria.
Funeral Rituals and Practices among U.S. Cultural Groups Funeral Rituals and Practices among U.S. Cultural Groups
A typical fuel-pump module assembly, which includes the pickup strainer and fuel pump, as well as ... A typical fuel-pump module assembly, which includes the pickup strainer and fuel pump, as well as ...
Maze-dull rats did not make significantly more errors than maze-bright rats when both groups were ... Maze-dull rats did not make significantly more errors than maze-bright rats when both groups were ...
Energy Use by Different Country Groups Energy Use by Different Country Groups
Video: Types of energy transfer reactions: oxidation-reduction reactions and ATP generation reactions

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