|
|
A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
A recent study has found that following a diet rich in berries may slow down the aging process of the brain. This diet apparently helps to keep dopamine levels much higher than are seen in normal individuals who do not eat berries as a regular part of their diet as they enter their later years.
It is widely believed that giving a daily oral dose of aspirin to heart attack patients improves their chances of survival because the aspirin blocks the formation of new blood clots.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
![the comet Encke riding along its pebbly trail of debris (long diagonal line) between the orbits of M](https://biology-forums.com/gallery/47/medium_12359_13_01_13_5_28_45.jpeg)
![Field research on free-living primates allows primatologists to study patterns of behavior in the se](https://biology-forums.com/gallery/47/medium_269691_26_01_15_5_55_23_204322151.jpeg)