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1.
Temporal lobe epilepsy with varying severity: MRI study of 222 patients   总被引:2,自引:0,他引:2  
MRI was performed in 222 consecutive adult patients with temporal lobe epilepsy of varying severity from January 1991 to May 1993. The diagnosis of hippocampal sclerosis was established visually by three independent observers. The accuracy of visual assessment of hippocampal asymmetry was compared with volumetric measurements. Neuropathological correlations were obtained in 63 patients with refractory seizures. Temporal lobe abnormalities were observed in 180 patients (81 %) as follows: hippocampal sclerosis in 122 (55 %); developmental abnormalities in 16 (7.2 %); tumours in 15 (6.8 %); scars in 11 (5 %); cavernous angiomas in 10 (4.5 %); miscellaneous lesions in 6. MRI was normal or showed unrelated changes in 42 patients (19 %). Visual assessment correctly lateralised hippocampal sclerosis in 79 of the 84 patients measured (94 %). Temporal lobectomy confirmed the MRI data (side and aetiology) in all 63 operated patients. Patients with normal MRI had an older age of seizure onset and were more often drug-responsive than patients with hippocampal sclerosis. MRI showed temporal lobe abnormalities in 81 % of epileptic patients with varying severity with good neuropathological correlation. Patients with normal MRI had a less severe form of the disease. Received: 19 August 1996 Accepted: 13 November 1996  相似文献   
2.
The synaptic connections established by grafted noradrenergic (NA) neurons into the lesioned adult rat spinal cord were analysed using immunocytochemistry at the electron microscopic level. An embryonic cell suspension of the locus coeruleus region from E-13 rat embryos was transplanted into the spinal cord following either: (1) spinal cord transection or (2), partial selective denervation by 6-hydroxy dopamine (6-OH DA). One month after grafting, the NA-neurons established, in the two models, an innervation pattern similar to that found in the intact spinal cord. In both models, the transplanted NA-immunoreactive neurons formed extensive synaptic contacts with dendrites, spines and perikarya. The proportion of axodendritic and axospinous contacts was inverse in the two models. The first model thus reproduced more closely the normal synaptic pattern prefering dendritic targets, which could correspond to a better integration of the graft. In the second model, a partially NA-denervated spinal cord, there existed a competition between residual intrinsic and grafted neuron-derived fibres, which presumably affects synaptogenesis. In conclusion, the present study illustrate the complexity of cell interations conducting to the formation of a specific circuitry. Recognition phenomenon are likely modulated by space constraints, which ultimately shape-up the geometry of synaptic contacts.  相似文献   
3.
Phonological representations in children with SLI: a study of French.   总被引:1,自引:0,他引:1  
The present research examined the quality of the phonological representations of French children with specific language impairment (SLI) and those with normal language development (NLD). Twenty-five children with SLI and 50 children with NLD matched on lexical age level participated in an auditory lexical decision task. The observations gathered in our study can be summarized as follows. First, children with a higher receptive lexical level performed better, and this was true both for children with NLD and children with SLI. Second, both children with NLD and those with SLI were more likely to reject pseudowords resulting from a modification affecting the number of syllables of a word than pseudowords resulting from a slight modification with the number of syllables unchanged. This difference, however, was greater for the children with SLI, who appeared to have much difficulty rejecting pseudowords resulting from slight modifications. Finally, the performance of children with SLI was particularly poor when presented with pseudowords resulting from a slight modification at the beginning or the end of a word. These findings are interpreted as supporting the hypothesis of an under-specification of phonological representations in children with SLI.  相似文献   
4.
The process of mononuclear cell extravasation from the blood into the islets of Langerhans in nonobese diabetic (NOD) mice is dependent on the expression of a set of molecules, most of which remain to be defined. The observation that vascular addressins are expressed in inflamed islets raises the issue of the involvement of one of their ligands, L-selectin, in the pathogenesis of autoimmune diabetes. Treatment of NOD females with Mel-14, an antibody specific for L-selectin, reduced the spontaneous development of both insulitis and diabetes. Pretreatment of diabetic donors with Mel-14 decreased the capacity of their splenocytes to transfer the disease. However, the treatment of recipients had no effect on the transfer of diabetes by untreated diabetogenic splenocytes. To reconcile these apparently conflicting results, we fractionated spleen T cells from diabetic mice according to L-selectin expression. Diabetogenic cells were found only in the L-selectin subpopulation. Thus, diabetogenic cells in adult mice share phenotypic characteristics with activated/memory cells, and enter the pancreas using L-selectin-independent migratory pathways.  相似文献   
5.
Subpopulations of lymphoid cells were compared with respect to their ability to migrate into peripheral lymphoid organs of nonobese diabetic (NOD) mice and various strains of control mice. In short-term, in vivo homing studies, no major differences in the pattern of homing of B and T cells were observed among all mouse strains studied. On the other hand, CD4 cells localized consistently more efficiently than CD8 cells in both PP and LN of adult NOD and BALB/c mice, whereas both populations migrated roughly equivalently in LN of adult DBA/2, CBA, and C57BL/6 mice. No age-dependent differences in the homing of CD4 and CD8 cells were observed in BALB/c mice. On the contrary, in 2-week-old NOD mice, CD4 and CD8 cells migrated equally well. The preferential entry of CD4 cells in adult NOD and BALB/c did not result from increased blood transit time of CD8 cells. On the other hand, the preferential migration of CD8 cells was observed in the liver, whereas the two T-cell subsets migrated equally well in the lungs. The differences in the homing characteristics of CD4 and CD8 cells among NOD, BALB/c, and C57BL/6 mice were not related to modifications in the level of expression of adhesion molecules such as MEL-14, LFA-1, and Pgp-1.  相似文献   
6.
The clinical and radiological spectrum of spondylocostal dysostosis syndromes encompasses distinctive costo‐vertebral anomalies. RIPPLY2 biallelic pathogenic variants were described in two distinct cervical spine malformation syndromes: Klippel–Feil syndrome and posterior cervical spine malformation. RIPPLY2 is involved in the determination of rostro‐caudal polarity and somite patterning during development. To date, only four cases have been reported. The current report aims at further delineating the posterior malformation in three new patients. Three patients from two unrelated families underwent clinical and radiological examination through X‐ray, 3D computed tomography and brain magnetic resonance imaging. After informed consent was obtained, family‐based whole exome sequencing (WES) was performed. Complex vertebral segmentation defects in the cervico‐thoracic spine were observed in all patients. WES led to the identification of the homozygous splicing variant c.240‐4T>G in all subjects. This variant is predicted to result in aberrant splicing of Exon 4. The current report highlights a subtype of cervical spine malformation with major atlo‐axoidal malformation compromising spinal cord integrity. This distinctive mutation‐specific pattern of malformation differs from Klippel–Feil syndrome and broadens the current classification, defining a sub‐type of RIPPLY2‐related skeletal disorder. Of note, the phenotype of one patient overlaps with oculo‐auriculo‐vertebral spectrum disorder.  相似文献   
7.
The sleeping brain differs from the waking brain in its electrophysiological and molecular properties, including the expression of growth factors and immediate early genes (IEG). Sleep architecture and homeostatic regulation of sleep in neonates is distinct from that of adults. Hence, the present study addressed the question whether the unique homeostatic response to sleep deprivation in neonates is reflected in mRNA expression of the IEG cFos, brain-derived nerve growth factor (BDNF), and basic fibroblast growth factor (FGF2) in the cortex. As sleep deprivation is stressful to developing rats, we also investigated whether the increased levels of corticosterone would affect the expression of growth factors in the hippocampus, known to be sensitive to glucocorticoid levels. At postnatal days 16, 20, and 24, rats were subjected to sleep deprivation, maternal separation without sleep deprivation, sleep deprivation with 2 h recovery sleep, or no intervention. mRNA expression was quantified in the cortex and hippocampus. cFos was increased after sleep deprivation and was similar to control level after 2 h recovery sleep irrespective of age or brain region. BDNF was increased by sleep deprivation in the cortex at P20 and P24 and only at P24 in the hippocampus. FGF2 increased during recovery sleep at all ages in both brain regions. We conclude that cortical BDNF expression reflects the onset of adult sleep-homeostatic response, whereas the profile of expression of both growth factors suggests a trophic effect of mild sleep deprivation.  相似文献   
8.
The European Journal of Health Economics - Cancer patients have one of the highest health care expenditures (HCE) at the end of life. However, the growth of HCE at the end of life remains poorly...  相似文献   
9.
Eribulin is widely used in the treatment of metastatic breast cancer, with a manageable toxicity profile. This aggressive disease often requires systemic and local treatments, comprising surgery or radiotherapy. However, eribulin is usually discontinued during radiation therapy due to the lack of data concerning the safety of this combination, especially in the setting of repeat locoregional radiation therapy. Our patient was diagnosed with ER positive invasive ductal carcinoma of the left breast initially treated by surgery, radiation therapy, chemotherapy, and hormone therapy. She then received various lines of chemotherapy for multiple triple-negative relapses in the left axillary region. Since October 2020, she has been treated by eribulin. In order to improve local control, it was decided to add local radiation therapy to the region of recurrence in addition to systemic therapy. She underwent radiation therapy concomitantly with eribulin from February to March 2021. Treatment was very well tolerated, and no acute toxicity was reported. This is the first published case of repeat locoregional radiation therapy in combination with eribulin.  相似文献   
10.
Language hemispheric dominance can be assessed by the Wada test before temporal lobectomy, in patients with refractory epilepsy of the mesial temporal lobe. Functional MR is a less invasive technique which recently demonstrated the ability to localize some language areas. The aim of this study was to determine if functional MR can be substituted to the Wada test in the determination of language dominance. Seven patients with a refractory epilepsy of the mesial temporal lobe were included. The MR protocol was carried out using a 1.5 T system including 12 axial gradient echo BOLD EPI images. A semantic fluency task, interspersed with rest periods, was used as activation paradigm. An activation of middle and inferior frontal region was found in all patients. It predominated in the left hemisphere in 6 cases and in the right hemisphere in 1 case. The hemispheric and frontal lobe lateralization of the functional MR activation was correlated with the hemispheric language dominance as assessed by the Wada test. In conclusion, functional MR is a promising technique in the determination of language dominance.  相似文献   
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