Resistance group

Many functional groups are stable to alkaline hydrogen peroxide. Acetate esters are usually hydrolyzed under the reaction conditions although methods have been developed to prevent hydrolysis.For the preparation of the 4,5-oxiranes of desoxycorticosterone, hydrocortisone, and cortisone, the alkali-sensitive ketol side chains must be protected with a base-resistant group, e.g., the tetrahydropyranyl ether or the ethylene ketal derivative. Sodium carbonate has been used successfully as a base with unprotected ketol side chains, but it should be noted that some ketols are sensitive to sodium carbonate in the absence of hydrogen peroxide. The spiroketal side chain of the sapogenins is stable to the basic reaction conditions. 

The radiation sensitivity of polymers and monomers is characterized by a G value the number of radicals formed per 100 e.v. (16 aJ) absorbed. Radiation sensitive groups include -COOH, C-halogen, -S02-, -NH2 and -C=C, Radiation resistant groups are aromatic rings. It appears that the presence of aromatic moieties also offers some degree of radiation protection to the polymer chain as a whole. 

Streptococcus pneumoniae Penicillin susceptible Penicillin intermediate Penicillin resistant Group B Streptococcus Staphylococcus aureus Methicillin susceptible Methicillin resistant Staphylococcus epidermidis Listeria monocytogenes... 

RADIATION-RESISTANT GROUPS. Aromatic groups have long been known to give significant radiation resistance to organic molecules. There was early work on the hydrogen yields from cyclohexane (G=5) and benzene (G=0.04) in the liquid phase, and of their mixtures, which showed a pronounced protective effect. 

The combination of radiation-sensitive and radiation-resistant groups is interesting. Halogen substitution of the phenyl group in polystyrene results in high radiation sensitivity with inter-molecular crosslinking. 

Group 1 — Fermentation and preservative resistance Group 2 — Spoilage and hygiene Group 3 - Hygiene Group 4 - Aliens... 

In 11 children with nephrotic syndrome, of whom five were glucocorticoid-sensitive, six glucocorticoid-resistant, and all resistant to other immunosuppressive drugs, levamisole 2.5 mg/kg was given every 48 hours for up to 18 months (7). Two patients were also given ciclosporin. All the patients in the steroid-sensitive group but none in the steroid-resistant group reacted favorably to levamisole, with disappearance of protein from the urine. There... 

Alan L. Devonshire Head of the Insecticide Resistance Group, JACK. Rothamsted, Harpendcn, UK, and Professor of Genetics a( Nottingham University. UK... 

This was a treatment-resistant group of patients who were substantially symptomatic despite current orthodox clinical treatment. The average 25% improvement in positive schizophrenia symptoms in the EPA group was significant not only statistically but was also clinically meaningful. Furthermore, the EPA treatment was not associated with adverse clinical side effects. 

Martin JM, Green M, Barbadora KA, et al. Erythromycin-resistant group A streptococcus in schoolchildren in Pittsburgh. N Engl J Med 2002 346 1200-1206. 

The conservation laws set is given by the stoichiometric coefficients q.., i = l,...n j = m +, ...n, representing the linear specific combinations of the number of particles which conserve the weight of the atomic species in molecules, or more generally, representing a so-called resistant group to transformations. 

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