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Biomedical subjects

R W Middleton

Publications and source records attributed to R W Middleton.

26 records · Page 2Linked to original sources

The mutagenicity of some novel phenyl-imidazopyridines.

The mutagenicity of some novel 2-phenyl-imidazopyridines was investigated by the Ames test. Those with nitro substituents, and 2 related nitrophenylpurines, were frame shift mutagens without liver activation. Similar compounds without nitro groups had no activity. The mutagenic compounds were more active against TA1538 than against TA98, and were also active against TA100, a base-pair substitution mutant. This unusual pattern of activity is similar to that of 2-nitrosofluorene and related compounds. Calculations of molecular size showed a relationship between the 2 groups of compounds, suggesting similar modes of action. The more potent mutagens were toxic at high concentrations. Many of the non-mutagenic compounds were toxic, depending upon their substituents. In general, the imidazol[4,5-c]pyridines were more biologically active than the imidazo [4,5-b]pyridines.

Animals↗

The place and efficacy of operative management of fractured clavicle.

A study of 22 cases of operative fixation of the fractured clavicle has been made. This has shown that with internal fixation and onlay bone grafting, highly successful results can be attained. There were no cases of non-union and there have been no significant complications. The indications for such surgery are presented from the literature. It is clear that the operation is not commonly indicated, but when performed is safe and highly successful.

Adolescent↗

Larsen's syndrome;.

Three cases of Larsen's syndrome with retospective diagnoses have been described. All of them had both the clinical and radiographic signs characteristic for the syndrome, namely flat, hyperteloric facies, multiple dislocations of the joints, club foot deformity, and long cylindrical fingers. The radiographic findings were generalized and diagnostic in all of the cases. Our patients had additional ossification centers for the body of calcaneus.

Abnormalities, Multiple↗