Extinction _____. only happens above the species level cannot happen to more than one species at a time has happened to over 99% of species that ever lived on earth happens when a species or population dies out.
Nivolumab, marketed as Opdivo, is a medication used to treat cancer.
6 Reviews. 6 Reviews. Macrobid is the brand name for nitrofurantoin, an antibiotic used to treat or prevent urinary tract infections. Macrobid works by killing the bacteria that cause the infection or by preventing the bacteria from growing.he recommended dose of Macrobid is different depending on whether it is being used to treat a urinary tract infection or prevent one. In general, here are the ranges of oral doses given: 1  50 to 100 milligrams (mg) at bedtime for adults and teens to prevent infections.