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1.
Three patients aged 5 1/2 to 9 years old with mutism after posterior fossa surgery are presented. The entity is discussed with a review of 15 additional previously reported cases in children aged 2 to 11 years. In all 18 patients, a large midline tumor of the posterior fossa (medulloblastoma in nine cases, astrocytoma in five, and ependymoma in four), often attached to one or both lateral recesses of the fourth ventricle, was removed. Mutism developed 18 to 72 hours after the operation (mean 41.5 hours) in patients with no disturbance of consciousness and no deficits of the lower cranial nerves or of the organs of phonation. All of these children had spoken in the first hours after surgery. The disorder lasted from 3 to 16 weeks (mean 7.9 weeks). Speech was regained after a period of dysarthria in six of the 10 cases for whom this information was available. The various hypotheses advanced to explain the pathogenesis of this speech disorder are analyzed. 相似文献
2.
Salvatore Serra Giuliana Brunetti Giovanni Vacca Carla Lobina Mauro A M Carai Gian Luigi Gessa Giancarlo Colombo 《Alcohol》2003,29(2):101-108
Results of a recent study have demonstrated that exposure to multiple ethanol concentrations and repeated ethanol deprivation periods in Indiana ethanol-preferring (P) rats resulted in the development of an alcohol deprivation effect (ADE; the temporary increase in voluntary ethanol intake after a period of deprivation from ethanol) characterized by consumption of intoxicating amounts of ethanol. The current study was designed to possibly extend these results to Sardinian alcohol-preferring (sP) rats, generated with the same selective program previously used for P rats. To this aim, ethanol-naive sP rats were exposed initially to the home cage four-bottle choice [10%, 20%, and 30% (vol./vol.) ethanol solutions and water] for eight consecutive weeks. Subsequently, rats were divided into two groups: The first group had continuous access to the four-bottle regimen (nondeprived rats), and the second group was exposed to five cycles of 14-day periods of deprivation from ethanol and 14-day periods of reexposure to the four-bottle regimen. An ADE developed after each deprivation period. However, the extra intake of ethanol was limited to the first hour of each reaccess period. Magnitude of ADE did not change with repeated periods of deprivation. However, a shift in preference toward the two highest concentrations of ethanol solutions was evident from the first reexposure to ethanol and was maintained throughout the study. These results provide further evidence on the heterogeneity of ethanol-drinking behavior among rat lines selectively bred for high ethanol preference and consumption. 相似文献
3.
Serum immunoglobulins including IgG subclasses were measured in 73 unselected children with asthma. The results showed that 22 (30%) had partial IgA and/or IgG4 subclass deficiency. Clinical assessment showed that 21 children were infection-prone, and 52 were not. Further analysis showed that infection-prone children were significantly different from non-infection-prone children with regard to familial history of allergy (29% vs 60%, p = 0.015), elevated IgE (62% vs 33%, p = 0.021), IgA deficiency (38% vs 15%, p = 0.38) and IgG subclass deficiency (24% vs 4%, p = 0.018). These results suggest that there may be subgroups of children with asthma who are also immunodeficient. 相似文献
4.
In rats bled to hypovolemic shock, the intracerebroventricular injection of hemicholinium-3 (20 micrograms/rat) completely prevented the shock reversal induced by the intravenous injection of ACTH (1-24) (160 micrograms/kg), but had no influence on the shock reversal induced by the intravenous injection of physostigmine (70 micrograms/kg). These data indicate that brain cholinergic neurons are involved in the anti-shock effect of ACTH-peptides, but not in that of centrally acting cholinergic drugs. 相似文献
5.
6.
D N Louis S M Meehan R J Ferrante E T Hedley-Whyte 《Journal of neuropathology and experimental neurology》1992,51(2):150-157
Because the distinction between gliosis and low-grade astrocytoma may prove difficult by routine light microscopy, we evaluated the silver nucleolar organizer region (AgNOR) technique in making this distinction. The AgNOR impregnation was performed on formalin-fixed, paraffin-embedded tissue from 49 central nervous system (CNS) biopsies: eight normal brain, 14 gliosis, 14 grade 2 astrocytoma (Daumas-Duport scale), two grade 4 astrocytoma, nine medulloblastoma, one metastatic carcinoma, and one choroid plexus papilloma. Quantitative and qualitative differences were found between gliosis and low-grade astrocytomas. In gliosis, AgNOR counts averaged 1.18 +/- 0.11 (SD) AgNOR/nucleus, while in low-grade astrocytomas AgNOR counts averaged 2.22 +/- 0.39 (p less than 0.001). Compound AgNOR were frequent in 9/14 grade 2 astrocytomas and in both grade 4 astrocytomas, whereas compound AgNOR were extremely rare in cases of gliosis. Quantitative and qualitative differences were also found between normal cerebellar internal granular cells and medulloblastoma cells. Cerebellar granular cells averaged 0.90 +/- 0.10 AgNOR/nucleus whereas medulloblastoma cells had an average of 4.52 +/- 0.95 (p less than 0.001). Compound AgNOR were seen in all medulloblastomas but not in internal granular cells. These findings suggest that the AgNOR technique may be a useful adjunct in the diagnosis of CNS neoplasia. 相似文献
7.
Characterization of the major neutrophil-stimulating activity present in culture medium conditioned by Staphylococcus aureus-stimulated mononuclear leucocytes. 总被引:1,自引:0,他引:1
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Culture medium conditioned by stimulating human mononuclear leucocytes (MNL) with killed Staphylococcus aureus (Scm) was found to contain a substantial amount of tumour necrosis factor-alpha (TNF-alpha) but no detectable tumour necrosis factor-beta (TNF-beta). Culture medium conditioned by MNL in the absence of bacteria contained no TNF-alpha activity. When Scm was fractionated by high-performance liquid chromatography (HPLC) on Bio-Sil TSK 250, TNF-alpha co-eluted with neutrophil-stimulating activity measured by chemiluminescence. Similarly, the ability of neutrophils to kill opsonized S. aureus was enhanced in fractions that contained this neutrophil-stimulating activity. The stimulating activity could be almost completely removed by pretreatment of the Scm with a TNF-alpha-specific monoclonal antibody (mAb). The ability of neutrophils to kill S. aureus in response to Scm was also substantially reduced by mAb to TNF-alpha. These results demonstrate that bacterial interaction with MNL leads to the release of neutrophil-stimulating activity that consists predominantly of TNF-alpha. 相似文献
8.
9.
Four species of Naegleria were tested for their ability to migrate under agarose. Pathogenic N. fowleri strains exhibited rapid locomotion at 37 degrees C. Environmental isolates of N. fowleri moved faster than clinical isolates which had been kept in axenic culture for longer periods, and this result was confirmed by using the 84-2205-7 strain kept in axenic culture for 1 or 5 months. Nonpathogenic N. gruberi strains migrated actively at 28 degrees C but not at 37 degrees C; moreover, even at 28 degrees C, active amoebae constituted only a small proportion of the whole. The temperature-tolerant, nonpathogenic species N. lovaniensis moved more slowly than N. fowleri at 37 degrees C. In contrast, N. australiensis, which is temperature tolerant as well as pathogenic for mice, migrated at a rate comparable to that of N. fowleri. There appears to be a direct correlation between the locomotive ability of free-living amoebae and their pathogenic potential. 相似文献
10.
G Pezzoli S Tesei C Ferrante E Cossutta A Zecchinelli G Scarlato 《Movement disorders》1988,3(1):37-45
In an open-label study, we substituted conventional levodopa plus benserazide: 100/25 (Madopar) with a controlled-release form (HBS) in 18 fluctuating parkinsonian patients for 24 months. Significantly positive results were obtained in both peak-dose and diphasic dyskinesias up to 12 months of treatment; morning akinesias were also improved up to 6 months. A general trend of deterioration, compared to the first 3-6 months of HBS treatment, was observed in "off" fluctuations after 1 year: akinesias due to a delayed response worsened after 1 year of treatment also when compared with the conventional treatment. Positive results were obtained with new HBS on standard Madopar-related psychiatric disorders. 相似文献