RESUMO
Transient potential changes evoked in response to light stimuli, and presumably arising from rhabdomeric eye-spots in the cercarial body, were recorded for the first time, to our knowledge, in helminth parasites. Pigmented Cercaria caribbea LXXI gave a very slowly adapting response to maintained light stimulus, while a non-pigmented variety appeared to emit a stronger, rapidly adapting response to light onset. Swimming towards a directional light source is disrupted by several neurophamacological agents, which presumably disturb synaptic transmission in the nerve/muscle system. The light evoked potentials were unaffected by these same agents and therefore, appeared to be directly recorded receptor potentials.(AU)
Assuntos
21003 , Caramujos/fisiologia , Células Fotorreceptoras/fisiologia , Eletrofisiologia , Potenciais Evocados , Movimento , Estimulação Luminosa , Valores de ReferênciaAssuntos
21003 , Crustáceos/anatomia & histologia , Crustáceos/fisiologia , Sistema Digestório/anatomia & histologia , Ecologia , Evolução Biológica , Extremidades/anatomia & histologia , Comportamento Alimentar , Locomoção , Mandíbula/anatomia & histologia , Mandíbula/fisiologia , Boca/anatomia & histologia , Movimento , Músculos/anatomia & histologiaRESUMO
We reviewed the cases of all patients with slipped capital femoral epiphysis at the University Hospital of the West Indies. Forty-seven hips in thirty-six Black patients were evaluated, and in 40 per cent of those hip chondrolysis developed. The appearance of roentgenographic changes of chondrolysis was predictable. There was a high percentage occuring within one year of diagnosis of slipped epihysis and within six months of closure of the proximal femoral growth plate. The persistent absence of motion in all planes following slipping of the capital femoral epiphysis was a constant finding in patients with chondolysis. This loss of motion can be diagnostic of impending chondrolysis and is usually present before the appearance of the roentgenographic changes. The microscopic changes suggest that the primary lesion is not necrosis of cartilage but a replacement of articular cartilage by pannus formation (Summary)