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

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Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.

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Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.

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Stevens-Johnson syndrome and Toxic Epidermal Necrolysis syndrome are life-threatening reactions that can result in death. Complications include permanent blindness, dry-eye syndrome, lung damage, photophobia, asthma, chronic obstructive pulmonary disease, permanent loss of nail beds, scarring of mucous membranes, arthritis, and chronic fatigue syndrome. Many patients' pores scar shut, causing them to retain heat.

Figure 7.1 shows the rapid decline in the trust of Americans in government since the 1960s. This de Figure 7.1 shows the rapid decline in the trust of Americans in government since the 1960s. This de
Unemployment and Federal Action, 1929–1941 Unemployment and Federal Action, 1929–1941
Adjusting a valve takes both hands—one to hold the wrench to loosen and tighten the lock nut and ... Adjusting a valve takes both hands—one to hold the wrench to loosen and tighten the lock nut and ...
Hold baby’s hands and (A) cross arms over chest and then (B) open out to the sides. Repeat several ... Hold baby’s hands and (A) cross arms over chest and then (B) open out to the sides. Repeat several ...
Main body cavities that hold human organs Main body cavities that hold human organs
Flowering plants such as papayas hold on to their spores and disperse by releasing seeds enclosed in Flowering plants such as papayas hold on to their spores and disperse by releasing seeds enclosed in
Video: Photosynthesis and Van Helmont Experiment

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