|
|
Signs of depression include feeling sad most of the time for 2 weeks or longer; loss of interest in things normally enjoyed; lack of energy; sleep and appetite disturbances; weight changes; feelings of hopelessness, helplessness, or worthlessness; an inability to make decisions; and thoughts of death and suicide.
Though methadone is often used to treat dependency on other opioids, the drug itself can be abused. Crushing or snorting methadone can achieve the opiate "rush" desired by addicts. Improper use such as these can lead to a dangerous dependency on methadone. This drug now accounts for nearly one-third of opioid-related deaths.
Many of the drugs used by neuroscientists are derived from toxic plants and venomous animals (such as snakes, spiders, snails, and puffer fish).
Amoebae are the simplest type of protozoans, and are characterized by a feeding and dividing trophozoite stage that moves by temporary extensions called pseudopodia or false feet.