Gram-positive bacteria show blue or purple after Gram-staining in a laboratory test. They have thick cell walls. Gram-negative bacteria show pink or red on staining and have thin walls.

This bacterium is a common cause of infections in hospitals, and now researchers are a step closer to understanding why.

Bacterial vaginosis is confined to an asymptomatic ... solution (positive whiff or sniff test). As an alternative, Gram-stain-based microbiological diagnosis of BV has been proposed.

Meningitis is a life-threatening condition caused by a bacterial or viral ... include a Gram stain test on cerebrospinal fluid to determine white blood cell count (total and differential), protein ...

All the pure bacterial isolates were characterized as Gram-positive or Gram-negative by the standard Gram staining method ... C overnight and then adjusted O.D. to 0.5 at 600 nm; the cells were ...