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This study examined the maturation of cortical auditory event-related potentials (ERPs) from birth until 12 months of age. In the 15 infants studied, all ERP peaks observable at 12 months of age, the P150, N250, P350, and N450 were identifiable already at birth, As in previous studies, the amplitudes of the ERP peaks increased and latencies shortened with increasing age. In addition, the time courses of the amplitude growth of these peaks differed from each other. It was concluded, that the generators of all the infantile ERP peaks are functional already at birth, and that the maturational changes in the waveform morphology can mostly be accounted for by the changing relative strengths of the different generators.  相似文献   
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Objective: To study neurodevelopmental outcome in a two year cohort of extremely low birthweight (ELBW) infants at 18 months corrected age, to compare the development of the ELBW infant subcohort with that of control children, and to find risk factors associated with unfavourable outcome. Study design: All 211 surviving ELBW infants (birth weight < 1000 g) born in Finland in 1996–1997 were included in a national survey. The ELBW infants (n = 78) who were born and followed in Helsinki University Hospital belonged to a regional subcohort and were compared with a control group of 75 full term infants. A national follow up programme included neurological, speech, vision, and hearing assessments at 18 months of corrected age. Bayley infant scale assessment was performed on the subcohort and their controls at 24 months of age. Risk factors for unfavourable outcome were estimated using logistic and linear regression models. Results: The prevalence of cerebral palsy was 11%, of all motor impairments 24%, of ophthalmic abnormalities 23%, and of speech delay 42%. No impairment was found in 42% of children, and 18% were classified as severely impaired. The prevalence of ophthalmic abnormalities decreased with increasing birth weight and gestational age, but the prevalence of other impairments did not. In the subcohort, a positive correlation was found between the date of birth and Bayley scores. Conclusion: Ophthalmic abnormalities decreased with increasing birth weight and gestational age, but no other outcome differences were found between birthweight groups or in surviving ELBW infants born at 22–26 weeks gestation. The prognosis in the regional subcohort seemed to improve during the short study period, but this needs to be confirmed.  相似文献   
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OBJECTIVE: To compare the safety and intraocular pressure (IOP)-lowering efficacy of once-daily travoprost (0.0015% and 0.004%) to twice-daily timolol 0.5%. DESIGN: Prospective, 6-month, randomized, controlled, multicenter, double-masked, phase III study. PARTICIPANTS: Six hundred five patients with open-angle glaucoma or ocular hypertension. METHODS: Patients with an 8 AM IOP between 24 to 36 mmHg in at least one eye (the same eye) at two eligibility visits received either travoprost 0.0015%, travoprost 0.004% (dosed every day), or timolol 0.5% (dosed twice daily). MAIN OUTCOME MEASURES: Mean IOP at 8 AM, 10 AM, and 4 PM in the patient's eye with the higher baseline IOP. RESULTS: The mean IOP was significantly lower for both concentrations of travoprost compared with timolol. Travoprost was statistically superior to timolol at 9 of 13 visits, with differences in IOP reductions ranging from 0.9 to 1.8 mmHg (0.0015%) and 10 of 13 visits with differences in IOP reductions from 0.9 to 2.4 mmHg (0.004%). Mean IOP changes from baseline ranged from -6.0 to -7.5 mmHg (0.0015%), -6.5 to -8.0 mmHg (0.004%), and -5.2 to -7.0 mmHg for timolol. Hyperemia was experienced at rates of 29.2% (59 of 202) for travoprost 0.0015%, 42.8% (86 of 201) for travoprost 0.004%, and 8.9% (18 of 202) for timolol. Iris pigmentation changes were observed in 1.0% (2 of 200) of patients receiving travoprost 0.004% with no changes noted in the travoprost 0.0015% group or the timolol group. A decrease in pulse and systolic blood pressure was observed in the timolol group. There were no other clinically relevant or statistically significant changes from baseline in ocular signs or laboratory values, and no serious, related, unexpected adverse events were reported for any group. CONCLUSIONS: Travoprost (0.0015% and 0.004%), dosed once daily in the evening, is statistically superior or equal to timolol 0.5% dosed twice daily at all treatment visits during this 6-month study. IOP reductions of up to 2.0 mmHg greater than timolol were found in the travoprost 0.004% pooled data group. Travoprost is safe and well tolerated in patients with open-angle glaucoma or ocular hypertension.  相似文献   
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Oxygen toxicity is thought to be an important factor involved in development of bronchopulmonary dysplasia (BPD) in the very preterm infant. Glutathione (GSH) plays a major role in the antioxidant defense system in the preterm lung and there are theoretical implications that N-acetylcysteine (NAC) treatment could improve its function. The purpose of this study was to investigate whether NAC treatment during the first week of life to preterm infants improved neonatal lung function as a measure of lung injury. The study was part of a multi-center Nordic controlled trial with prophylactic intravenous NAC treatment (16-32 mg/kg/day) for 6 days in newborn infants with birth weights 500-999 g. Lung mechanics, with calculations of compliance and resistance of the respiratory system, together with measurements of functional residual capacity and indices of gas mixing efficiency in the lung, were performed in 33 preterm infants (18 received NAC and 15 placebo) before discharge from the NICU. Median (range) gestational age was 25 (24-28) weeks in the NAC-treated infants and 25 (24-29) in the placebo group. Corresponding mean (SD) birth weights were 0.774 (0.11) and 0.761 (0.12) kg respectively. Lung function measurements did not show any significant differences between NAC-treated infants compared to placebo when examined before discharge from the NICU. We conclude that prophylactic NAC treatment to extremely low birth weight infants during the first week of life does not improve lung function at term.  相似文献   
48.
Magnetic brain responses to speech sounds were measured in 10 healthy neonates. The stimulation consisted of a frequent vowel sound [a:] with a steady pitch contour, which was occasionally replaced by the vowel [i:] with a steady pitch, or the vowel [a:] with a rising pitch, manifesting a change of intonation. The magnetic mismatch-negativity response (MMNm) was obtained and successfully modelled to the speech sound quality change in all infants and to the intonation change in 6 infants. The present results indicate that auditory-cortex speech-sound discrimination may well be studied with magnetic recordings as early as in newborn infants.  相似文献   
49.
OBJECTIVE: The authors compared the new extended-release and standard preparations of divalproex sodium. METHOD: Twelve patients with DSM-IV bipolar disorder or schizoaffective disorder who were clinically stable while taking the standard form of divalproex participated in the study. These patients were given a single daily dose of the extended-release preparation of divalproex in an open 6-week trial. Clinical symptoms and adverse effects were rated weekly. Doses were adjusted to maintain steady serum valproate concentrations. RESULTS: The medication change was associated with negligible changes in clinical status and tolerability. To maintain serum drug levels, however, 21% higher doses of the extended-release preparation were required. CONCLUSIONS: Use of extended-release divalproex once a day was as well tolerated as the standard preparation, with no change in efficacy within 6 weeks, but the daily dose needed to maintain stable serum valproic acid concentration was 21% higher.  相似文献   
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