A small, gram-negative coccobacillus is isolated from a lymp…
A small, gram-negative coccobacillus is isolated from a lymph node aspirate of a hunter with ulceroglandular symptoms after handling wild rabbits. The organism grows poorly on standard media, but appears after 48 hours on cysteine-enriched chocolate agar. The organism is oxidase negative and provides a weak postive catalase reaction. The technologist presumptively identifies the isolate as Francisella tularensis. What is the next best step?
Read DetailsA child presents with an infected finger after having been b…
A child presents with an infected finger after having been bitten by his pet cat. The culture of the wound grew a pure culture of gram negative the organism shown below on gram stain. Additional characteristics of this organism include: Indole – positive Catalase – positive Oxidase-positive Urease-negative No Growth on MAC The most likely identification is which organism?
Read DetailsA 55-year-old man is admitted with high fever, non-productiv…
A 55-year-old man is admitted with high fever, non-productive cough, and hyponatremia. A sputum gram stain shows many neutrophils but no visible organisms. Routine bacterial cultures are negative after 48 hours. The clinician suspects Legionella pneumophila infection. What is the most rapid and specific test for confirming the diagnosis?
Read DetailsThe gram stain of a pericardial fluid shows many tiny gram-n…
The gram stain of a pericardial fluid shows many tiny gram-negative coccobacilli. There is no growth on blood agar at 24 hours, but the chocolate agar shows small translucent colonies. The microbiologist performs a porphyrin test, which is positive. The organism should be identified as:
Read Details13. (WCSP[x], 6 points) Draw three constitutional isomers of…
13. (WCSP[x], 6 points) Draw three constitutional isomers of the molecular formula of C5H10O. Isomer A should include a aldehyde. Isomer B should include an alcohol. Isomer C there are no requirements! Get creative! Give the number of sigma bonds in Isomer A in the box below.
Read DetailsA pediatric patient is brought to the clinic with acute onse…
A pediatric patient is brought to the clinic with acute onset of bilateral conjunctival redness, tearing, and crusting around the eyes. Several classmates have developed similar symptoms. A conjunctival swab is collected for culture. Gram stain shows small, pleomorphic gram-negative coccobacilli. What is the most common cause of the described illness?
Read Details(WCSP25) The cross sections of three different ionic compou…
(WCSP25) The cross sections of three different ionic compounds (labeled Compound 1, 2 and 3) are displayed in the figures below. In the figures, the charge on each ion is indicated, and the diameter of each circle reflects the diameter of each ion. Rank these compounds in order of increasing melting point. lowest [drop1] < [drop2] < [drop3] highest
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