avian paramyxovirus type i infection in pigeons clinical observations an outbreak of a neurological disease in pigeons caused by avian paramyxovirus type i occurred in the new york metropolitan area in 1984 it was characterized clinically by head tremors paresis of the wings and legs ataxia torticollis and loose droppings clinical pathologic evaluation revealed anemia and elevated plasma transaminase enzymes mortality was virtually 100 in juvenile pigeons whereas the adults generally experienced much lower morbidity and mortality ring uncemented hip replacements the results of revision since 1964 3573 uncemented ring total hip replacements of all types have been performed 194 54 have required revision for infection loosening or breakage of these 102 were available for review 81 had satisfactory results five years after operation these results are better than many of those reported after revision of cemented hip replacements it is suggested that the absence of cement makes revision easier because bone erosion rarely occurs