Gram negative


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Gram negative

Used of a micro-organism that when stained by Gram's method does not retain the purplish dye, methyl violet, but only the red counter-stain carbol fuchsin. Stained Gram negative organisms appear red. The whole class of medically important bacteria can be divided into a large GRAM POSITIVE group and a smaller Gram negative group. This division is an important step in identification. (Hans Christian Joachim Gram, 1853–1938, Danish physician).
References in periodicals archive ?
Isolation and identification: Gram negative bacteria were isolated and identified following Bergey's Manual of Determinative Bacteriology (1994).
1 Enterobacter species were the most common nosocomial pathogen among Gram negative bacteria and was the cause of pneumonia in 11% of pneumonia cases.
8 A panel of 13 drugs was applied for Gram negative organisms and a panel of 12 drugs for Gram positive organisms (Table 1).
Based on morphological characteristics, PL 13 was confirmed as a bacteria because it have coccus shaped and gram negative characteristic.
However, endospores were not visualized initially, and the organisms persistently stained gram negative.
Use of the limulus amebocyte lysate test as a cost effective screen for Gram negative agents of meningitis.
Additional 5 cases which included 4 cases of culture negative pneumococcal meningitis and 1 case of culture negative Gram negative bacillary meningitis could be detected by their typical morphology in the centrifuged Gram smear (Table 2 and 3).
Hospitalized patients greater than 15 years of age with gram negative bacteraemia were included and followed for a period of 2 weeks for in hospital mortality.
Detection of ESBL producing nosocomial gram negative bacteria from a tertiary care hospital in Bangladesh.