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Did you know?

For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.

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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.

Did you know?

Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.

Did you know?

According to the CDC, approximately 31.7% of the U.S. population has high low-density lipoprotein (LDL) or "bad cholesterol" levels.

Did you know?

Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.

Bones of the Face and Skull (Lateral View) Bones of the Face and Skull (Lateral View)
Palatine bones Palatine bones
Zygomatic bones Zygomatic bones
The cranium of a young infant changes dramatically in shape with age. Initially the child has severa The cranium of a young infant changes dramatically in shape with age. Initially the child has severa
Adolescent girls reach adult height sooner than boys because their bones grow more rapidity Adolescent girls reach adult height sooner than boys because their bones grow more rapidity
The Facial Bones The Facial Bones
Video: Major Elements in Biological Molecules: Nucleic acids

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