|
|
People who have myopia, or nearsightedness, are not able to see objects at a distance but only up close. It occurs when the cornea is either curved too steeply, the eye is too long, or both. This condition is progressive and worsens with time. More than 100 million people in the United States are nearsighted, but only 20% of those are born with the condition. Diet, eye exercise, drug therapy, and corrective lenses can all help manage nearsightedness.
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
Liver spots have nothing whatsoever to do with the liver. They are a type of freckles commonly seen in older adults who have been out in the sun without sufficient sunscreen.
The types of cancer that alpha interferons are used to treat include hairy cell leukemia, melanoma, follicular non-Hodgkin's lymphoma, and AIDS-related Kaposi's sarcoma.
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.
![Lymphatic vessels pick up excess tissue fluid, purify it in the lymph nodes, and then return it to t](https://biology-forums.com/gallery/47/medium_14755_01_10_12_7_59_21_92301561.jpeg)
![Pericardial effusion: A, normal pericardial sac; B, pericardial sac with excess fluid possibly causi](https://biology-forums.com/gallery/47/medium_18099_24_10_12_3_03_45.jpeg)