Gram-positive microorganisms

These antibiotics are effective in die treatment of infections caused by a wide range of gram-negative and gram-positive microorganisms. The tetracyclines are used in infections caused by Rickettsiae (Rocky Mountain spotted fever, typhus fever, and tick fevers). Tetracyclines are also used in situations in which penicillin is contraindicated, in the treatment of intestinal amebiasis, and in some skin and soft tissue infections. Oral... 

Rifaximin selected resistant Gram-positive cocci mutants more easily under aerobic conditions than in an anaerobic atmosphere [46, 48]. In comparison with Gram-positive microorganisms, drug-resistant Gramnegative bacilli were rarely detected [46, 48],... 

The answer is b. (Hardman, p 1077.) Unlike the other listed drugs, oxacillin is resistant to penicillinase. The other four agents are broad-spectrum penicillins, while oxacillin is generally specific for Gram-positive microorganisms Use of penicillinase-resistant penicillins should be resewed for infections caused by penicillinase-producing staphylococci... 

Another type of semisynthetic penicillin that should undoubtedly be considered is penicillin derivatives of heteroylcarboxylic acids (as a rule an isoxazol) in the third position of which is present a substituted or nonsubstituted phenyl radical (oxacillin, cloxacilhn, dicloxaciUin), which plays the role of the radical in the acyl side group. These penicillins (oxacilhn, cloxacilhn, dicloxacilhn), which are resistant to penicillinase, are active with respect to peniciUin-G-resistant staphylococci. Their antimicrobial spectrum is restricted to Gram-positive microorganisms. 

Second-generation cephalosporins (cefuroxime, cefamandole, cefoxitin, cefotetan, cefaclor, and others) are characterized by high activity with respect to Gram-positive microorganisms that are resistant to beta-lactamase action. They do not have a noticible effect on enterococci. 

Norfloxacin possesses a broad spectrum of bactericidal action. It is highly active with respect to most Gram-negative and a few Gram-positive microorganisms. Anaerobic... 

In addition, the antibiotics and other bacteriocins were originally detected in lactic acid bacteria, but were later also found in other Gram-positive microorganisms [28]. Lactic acid bacteria are a group of non-spore-forming, anaerobic fermentative bacteria within the Gram-positives with low GC content. 

Is specific for Gram-positive microorganisms Is a potent inhibitor of cell-wall transpeptidase Inactivates bacterial P-lactamases Has a spectrum of activity similar to that of penicillin G... 

It is resistant to degradation by penicillinase. Mainly it exhibits activity against gram positive microorganisms and is useful against penicillinase producing Staph. 

Anaerobic gram-positive microorganisms Clostridium perfringens... 

Mass Spectrometry Usage of analytical devices that can determine the mass (or molecular weight) of proteins and nucleic acids, the sequence of protein molecules, the chemical organization of almost all substances and the identification of gram-negative and gram-positive microorganisms. 

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