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Modified by future laboratory results fluorescent ab

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modified by future laboratory results. Fluorescent Ab detection of an organism in sputum is more specific than gramstaining. Here specific known Abs (single or in a mixture) are used to identify organisms present.A 30-year-old male presents to the emergency room with high fever and malaise which he reports began 4 days ago and gotprogressively worse each day. He appears underweight and very ill. Physical examination reveals needle marks in bothantecubital fossae. Listening for heart sounds, you hear a distinctive systolic heart murmur. You order blood cultures andmake a presumptive diagnosis of acute bacterial endocarditis. Following is the growth curve of the organism growing in anutrient medium at 35°C with both O2and added CO2present.On which of the following growth phases would treatment with gentamicin have a maximal effect?A. Lag phaseB. Log phaseC. Stationary phaseD. Death phaseThe answer is B.EXPLANATION:Bacterial growth curves are multiphasic. The lag phase is characterized by lack of growth but notnecessarily metabolic activity. The bacteria are "adjusting" to their new environment. Depending on the bacteria, thetemperature, nutrients, and pH, the microorganisms start dividing after a few hours and grow logarithmically for 12 to 18hours. Toxins accumulate in the medium and nutrients become limiting. Oxygen and carbon dioxide are usually notlimiting, as the gases freely diffuse into the growing culture. When death and growth of cells are equal, the stationary phaseoccurs. The death phase is characterized by a death rate that is more rapid than the growth rate. An antibiotic that inhibitsprotein synthesis would be optimally active in a rapidly dividing culture, where proteins are being rapidly synthesized, thatis, the logarithmic phase. Bacteria introduced into the human host may undergo similar phases of growth. However, otherfactors such as host defenses play a major role in limiting logarithmic growth, as do accumulation of toxic by-products asmight occur in a closed-space infection such as an abscess.
At least 15 species ofMycoplasmaare of human origin, and five are of primary importance. Which of the followingorganisms normally inhabits the female genital tract and is strongly associated with salpingitis and ovarian abscesses?
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E.Ureaplasma urealyticumThe answer is B.EXPLANATION:The only other species ofMycoplasmaassociated with human disease isM hominis.A normalinhabitant of the genital tract of women, this organism has been demonstrated to produce an acute respiratory illness that isassociated with sore throat and tonsillar exudate, but not with fever.Mycoplasma hominiscan cause disease outside theurinary tract in immunosuppressed patients or immunocompetent patients after trauma of the genitourinary tract. Otheropportunistic infections known to be caused byM hominisincludes wound infections, osteomyelitis, brain abscess,

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Term
Spring
Professor
NEWSOME
Tags
Hepatitis A, A Age

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