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991.
Neurophysiological evidence of auditory channel anomalies in developmental dysphasia 总被引:2,自引:0,他引:2
Steady-state auditory evoked responses to frequency-modulated tones were obtained from normal children and two groups of children with developmental language disorders (developmental dysphasia). Children with predominantly expressive language impairment produced responses not different from normal children, while children with primary receptive language impairment produced responses that were markedly diminished, even absent. This occurred in recordings from either cerebral hemisphere and at mean frequency-modulation depths ranging from +/- 20 to +/- 100 Hz. Pathophysiology of auditory mechanisms concerned with frequency-modulation analysis are particularly associated with receptive developmental language impairment and may underlie associated difficulties in speech perception. 相似文献
992.
993.
The role of infection and vaccination in the genesis of optic neuritis and multiple sclerosis in children 总被引:2,自引:0,他引:2
R. Riikonen 《Acta neurologica Scandinavica》1989,80(5):425-431
This article describes the association between previous infection and/or vaccination and the development of optic neuritis (ON) in 18 children. Ten of these children subsequently developed clinically definite multiple sclerosis (MS), while in 8 patients a clinically definite etiology could not be confirmed. Vaccination preceded the first ON attack in 6 patients, all but one of whom subsequently developed MS. It also preceded subsequent demyelinating events in 6 patients. Ten of the patients had a bacterial or viral infection within the 2 weeks prior to the first symptoms of ON. Intrathecal antibody synthesis against 2 or more viruses could be shown in 5 out of 8 patients studied; 5 out of 6 patients had oligoclonal antibodies in CSF and 12 out of 16 patients a high IgG index. Neither intrathecal antibody synthesis against 2 or more viruses nor elevated IgG indexes could be found in the control patients. Measles and mumps occurred at a significantly later age in the children who subsequently developed MS than in the control children, and these patients had significantly more events that might have impaired the blood-brain barrier than the controls. These results indicate that immunological events leading to MS may be triggered during childhood. Vaccination and infection often precede ON in childhood. Intrathecal viral antibody production can occur already in childhood at the time of the first symptoms of MS. 相似文献
994.
J A Scatina D R Hicks M Kraml M N Cayen 《Xenobiotica; the fate of foreign compounds in biological systems》1989,19(9):991-1002
1. The disposition of AY-30,068 (I), a new tetrahydrocarbazole analgesic drug, was studied in mice, rats, dogs, rhesus monkeys, and man. 2. Oral doses of the 14C-labelled drug in aqueous solution were well absorbed in rodents, but absorption of oral doses of the crystalline drug in dogs was poor. Due to the virtual absence of serum metabolites in rats and dogs, the bioavailability of I was nearly identical to the extent of absorption. Although a small first-pass effect was observed in mice, unchanged I represented a major portion of serum radioactivity. 3. A linear increase in the serum concentrations of I occurred at doses between 0.05 and 25 mg/kg in rats, 0.1 and 50 mg/kg in dogs, and 1-160 mg in man. In rhesus monkeys given a 0.5 mg/kg oral dose, the Cmax and AUC of I were similar to values obtained following a corresponding dose in dogs. 4. After i.v. administration of a 1.0 mg/kg dose the terminal elimination half-life (t1/2 beta) of I was 4 h in mice and 9-10 h in rats and dogs. In rodents, dogs, and several human subjects, the elimination of I was interrupted by secondary peaks. Enterohepatic circulation was confirmed in bile duct cannulated rats, where the t1/2 beta of I was decreased to 2.4 h. In rodents the serum clearance and apparent volume of distribution of I were 0.04-0.2 l/kg.h and 0.5-0.8 l/kg, respectively, and 0.6 l/kg.h and 9.8 l/kg in dogs. 5. In rodents and dogs dosed with 14C-labelled I, radioactivity was excreted almost entirely in the faeces. No unchanged I was detected in rat bile, while about 70% of the radioactivity corresponded to conjugates of parent drug. 相似文献
995.
Dermal absorption of the insecticide lindane was determined following topical application of ring 14C-labeled lindane to the tail of Sprague-Dawley rats. The tail was tested as a practical alternative to the rat mid-dorsal (back) region, and the data obtained were compared to those with rat back and with those of rhesus monkeys in our previous reports. There was no significant difference between total percentage urinary 14C recovery for rats dosed on the tail with occlusive tail covers (52 +/- 6.2%; t1/2 = 2.7 d) compared to those with nonocclusive covers (55 +/- 4.4%; t1/2 = 2.9 d). Neither the total percentage urinary recovery nor the t1/2 values obtained for the rat tail and rat back models differed significantly. Carbon-14 activity was still detectable in urine samples taken after 72 d post-treatment. However, an extensive tissue analysis failed to demonstrate 14C activity persisting at 72 d, with the exception of trace levels detected in blood serum and tail tissue. Advantages of the rat tail model are highlighted. 相似文献
996.
G D Johnston 《Drugs》1989,37(5):577-582
997.
European Surgery - Es werden in einer retrospektiven Studies die Ergebnisse von 101 Patienten, welche wegen einer komplizierten Kolondivertikulitis in den Jahren 1965 bis 1978 operiert wurden, den... 相似文献
998.
999.
1000.