Gram positive, definition

The mechanism of antibacterial activity is through inhibition of gram-positive bacterial cell-wall synthesis thus, the penicillins are most effective against actively multiplying organisms. Because mammalian cells do not have a definitive cell-wall stmcture as do bacteria, the mammalian toxicity of the penicillins is low. Allergic phenomena in patients following sensitization may occur. 

Almost all antibacterial agents have been observed to cause diarrhea in a variable proportion of patients (114,115). The proportion depends not only on the antibiotic, but also on the clinical setting (in-patient/out-patient), age, race, and the definition of diarrhea. Severe colonic inflammation develops in a variable proportion of cases, and in some cases pseudomembranous colitis occurs (116-121). Since 1977, much evidence has accumulated that the most important causative agent in antibiotic-associated diarrhea is an anaerobic, Gram-positive, toxin-producing bacterium, C. difficile (122-124). 

The fight against bacterial infection is one of the great success stories of medicinal chemistry. The topic is a large one and there are terms used in this chapter which are unique to this particular field. Rather than clutter the text with explanations and definitions, Appendices 4 and 5 contain explanations of such terms as antibacterial, antibiotic, Gram-positive, Gram-negative, cocci, bacilli, streptococci, and staphylococci. 

Amphomycin is mainly active against gram-positive bacteria, with little or no activity against gram-negative bacteria or yeast . As its sodium salt, amphomycin has definite therapeutic effects against experimental Tr. gambiense and Tr. rhodesiense infections in mice and a curative value for fatal avian spirochetosis in chicks . It has successfully protected mice infected by intraperitoneal inoculation with 100 ISD oi Diplococcus pneumoniae ". It has been reported that the antibacterial activity of crystallomycin and amphomycin is lower in the presence of phosphates, but is completely restored after their removal (Table 1.7). 

Fluoroquinolones designate distinctly an improvement of the earlier structural analogues, such as cinoxacin, nalidixic acid, oxolinic acid, and pipemidic acid, for being relatively much more potent in vitro. Besides, the fluoroquinolones do exhibit a definitely broader antibacterial spectrnm, the essentially consist of both Gram-positive and Gram-negative microorganisms. 

The matrix U was eliminated from equations (see the text before Eq. 12.6) by using Gram-Schmidt orthonormalization. This orthonormalization can be performed in R supposing that the operator V is positive definite and that the norm i V j) exists. If we keep the norm of radial projectors fixed and just V-ortogonalize the basis (and so diagonalize U), we obtain the solution also for non-positive definite pseudopotential. Using the coefficients... 

In the Trauzl test, the mixture produced an expansion of 24 cc./gram, which is indicative of a high energy reaction. Card gap tests were also positive the value at room temperature is approximately 25 cards. From these results it was concluded that a mixture of methylene chloride with nitrogen tetroxide constitutes a definite explosive hazard. This conclusion was not immediately apparent as a result of compatibility and impact testing alone. Methylene chloride was not recommended as a solvent for cleaning N2O4 systems instead, a water flush is used for this operation. 

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