|
|
Parkinson's disease is both chronic and progressive. This means that it persists over a long period of time and that its symptoms grow worse over time.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
Nearly all drugs pass into human breast milk. How often a drug is taken influences the amount of drug that will pass into the milk. Medications taken 30 to 60 minutes before breastfeeding are likely to be at peak blood levels when the baby is nursing.
Human neurons are so small that they require a microscope in order to be seen. However, some neurons can be up to 3 feet long, such as those that extend from the spinal cord to the toes.
Drugs are in development that may cure asthma and hay fever once and for all. They target leukotrienes, which are known to cause tightening of the air passages in the lungs and increase mucus productions in nasal passages.
![The path of blood flow through the chambers of the left and right side of the heart, including the v](https://biology-forums.com/gallery/47/medium_14755_10_09_12_7_22_09_8519715.jpeg)
![In the summer of 1793, a yellow fever epidemic struck Philadelphia, killing nearly 4,000. Tens of th](https://biology-forums.com/gallery/47/medium_374628_16_08_15_9_52_07_222511109.jpeg)