Ralph Michaelis

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The results of a collaborative study of bilateral spastic cerebral palsy (BSCP) between south-west Germany and western Sweden are reported, comprising 249 children in south-west Germany and 264 children in western Sweden. A severe gross motor disability was present in 65 per cent of the German and 62 per cent of the Swedish children; learning difficulties(More)
Acquisition and retention of tolerance to ethanol's rate-decreasing effects on operant performance were examined in rats which received a 52-day regimen of ethanol or saline injections prior to and/or after each daily session. Eight groups of rats differed on: (a) number of days with intoxicated practice (pre-session ethanol); (b) intermittent (spaced) or(More)
MRI of the brain was performed on 56 children with bilateral spastic cerebral palsy (CP) at a mean age of 10.7 years. Specific pathology was found in 91 per cent; periventricular leukomalacia was present in 42 per cent of term- and 87 per cent of preterm-born children. Parasagittal subcorticocortical injury, multicystic encephalomalacia and basal ganglia(More)
Thirty eight children with bilateral spastic cerebral palsy underwent MRI at the age of 5 years and more. Twenty nine showed correlates of periventricular leucomalacia, which were found especially in preterms (20 out of 21) but also in 9 of 15 fullterms without birth asphyxia. These findings suggest compromising events in the peri- and neonatal period(More)
Twelve male Sprague-Dawley rats were trained in a standard two-choice Drug 1-Drug 2 discrimination task utilizing 3.0 mg/kg chlordiazepoxide (CDP, an anxiolytic drug) and 20 mg/kg pentylenetetrazol (PTZ, an anxiogenic drug) as discriminative stimuli under a VR 5-15 schedule of food reinforcement. Saline tests conducted at specific time points after acute(More)
Pregnant rats were intubated during days 10-14 of gestation with equal volumes of isocaloric ethanol-sucrose solutions. Groups 8g, 4g, and 0g received one-half these amounts of ethanol per kg body weight twice each treatment day. Although these maternal treatments did not significantly affect offspring birth weights, activity levels during classical(More)
The effects of caffeine upon the discriminative and rate-altering effects of cocaine were examined in rats. Using a food-reinforced two-lever operant procedure, 12 Sprague-Dawley male rats were trained to discriminate between 10 mg/kg cocaine and saline. Stimulus generalization tests with both cocaine and amphetamine resulted in a dose-related increase in(More)
Although caffeine-phenylethylamine combinations are widely available as over-the-counter medications or as "legal" stimulants, little information is available concerning their behavioral pharmacology or abuse potential. In the present study, rats were trained in a food-reward, two-lever operant drug discrimination paradigm to differentially respond after(More)
The phenotype of severe congenital hydrocephalus secondary to neural cell adhesion molecule L1 (L1CAM) gene mutations includes the distinct finding of brainstem corticospinal tract hypoplasia. Using diffusion-weighted imaging (DWI), we failed to demonstrate anisotropy in the corticospinal tracts of the basis pontis in 4 affected boys with L1CAM mutations.(More)