Effects of increasing bupivacaine concentrations on spinal cord. Experimental study in dogs - Ganem, Eliana Marisa [UNESP]; Vianna, Pedro Thadeu G. [UNESP]; Marques, Mariangela [UNESP]; Castiglia, Yara M. M. [UNESP]; Vane, Luis Antonio [UNESP] (My University, 1993)