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71.
Cytogenetic examinations were carried out in 40 children with acute leukaemia. In 18 cases karyotype changes were demonstrated, in 8 cases the karyotype was normal, in 14 cases no cell division was obtained and these patients were excluded from further analysis. In the group with karyotype changes in most cases poor prognosis indices were found, including high number of blasts, extramedullary presence of leukaemic infiltrations and FAB L2 or L3. Chromosomal abnormalities included presence of aberrations in the form of translocation, mosaicism of karyotypes with nearly tetraploidy line, accessory marker chromosomes and other anomalies. In this group 8 children died (30% of all observed cases), while in the group without karyotype changes 2 children died (about 8%). In summary the authors stress the correlation between the presence of clinical prognostic factors (risk factors) and karyotype changes and worse prognosis in cases with chromosomal abnormalities. Attention is called to the great usefulness of cytogenetic examinations in the prognosis and treatment of leukaemias in children.  相似文献   
72.
In six young and two senile MS cases perivascular astrocytes within demyelination lesions were evaluated immunocytochemically. The peroxidase-antiperoxidase method of Sternberger et al. (1970) was used for visualization of glial fibrillary acidic protein (GFAP). In all cases very weak immunoreactivity of perivascular astrocytes was noted. Accumulation of perivascular glial fibers, and infrequently their fragmentation were observed both within active and old demyelination plaques. Clasmatodendrosis, Rosenthal's fibers and prominent regressive changes of astrocyte perikarya were found only in old plaques. A lack of immunoreactivity of perivascular astrocytes was noted within old demyelination lesions. The background of the latter was often immunonegative to GFAP. It is suggested that secondary damage of perivascular astrocytes influences vascular permeability within demyelination lesions including old plaques.  相似文献   
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Alprazolam, a new benzodiazepine from triazolobenzodiazepine group, produced anxiolytic action in the conflict test with potency similar to that of diazepam. The myorelaxant activity of the drug was relatively weak. Unlike desipramine, alprazolam failed to reduce the immobility of rats in the forced swim test and was unable to prevent clonidine-induced hypothermia. Alprazolam, unlike desipramine, failed also to potentiate behavioral effect of noradrenaline injected into the hippocampus. Alprazolam after acute but not chronic administration antagonized the synchronizing effect of clonidine on EEG pattern. On the other hand, alprazolam similarly to tricyclic antidepressants, prevented the suppression of dominance behavior by clonidine in rats competing for food. The results indicate that alprazolam acts only weakly upon noradrenergic mechanisms related to depression and to antidepressant action of drugs.  相似文献   
75.
A case of primary malignant lymphoma of the eye in a 78-year-old woman is reported. A centroblastic non-Hodgkin lymphoma showed prominent involvement of the retina with massive serous retinal detachment. A review of the literature is given.  相似文献   
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OBJECTIVES: To develop an immune-competent animal model for mucosally derived squamous cell carcinoma (SCCA). STUDY DESIGN: Fifteen Fischer 344 rats were inoculated with 1, 2, 5, 10, or 20 x 10(6) FAT7 cells in their flanks. The animals were observed for tumor growth and metastasis. RESULTS: All animals developed tumors that grew exponentially. Pulmonary metastases developed in all animals and 13% developed lymph node metastases. CONCLUSION: The FAT7 flank tumor in Fischer 344 rats is a new animal model that closely resembles the behavior of human mucosal head and neck cancer. SIGNIFICANCE: The existence of an immune-competent, mucosally derived, and reliable animal model of SCCA that somewhat resembles human head and neck SCCA gives the opportunity to perform immune-modulating experiments on head and neck cancer in these animals. EBM rating: B-3.  相似文献   
80.
Early results (12 weeks after surgery) of the lumbar spinal stenosis operative treatment were assessed in the group of 36 patients (aged 40-65 years). In 72% of patients posterior fusion was applied. In the results evaluation lumbar pain, low extremities pain, neurogenic claudicat ion, sensory disturbances and functional status were taken in account. A significant decrease in low extremities and lumbar pain was observed. Some sensory disturbances after operative treatment did not affect general high patients assessment of the performed surgical procedures (positive 80.5% cases).  相似文献   
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