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991.
Shimizu T  Saito N  Aihara M  Kurihara H  Nakazato Y  Ueki K  Sasaki T 《Surgical neurology》2004,61(1):77-81; discussion 81
BACKGROUND: Primary oligoastrocytomas of the spinal cord are rare, and the treatment options for low-grade intramedullary tumors are controversial. DESCRIPTION: A 10-year-old girl presented with thoracic scoliosis. Magnetic resonance imaging (MRI) revealed an enhancing intramedullary mass lesion extending from C-5 to T-5, associated with whole spine syringomyelia and syringobulbia. (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET) showed high uptake in the lesion. The patient underwent C-5 to T-5 laminoplastic laminotomy and subtotal removal of the tumor. Histologic examination revealed that the tumor was an oligoastrocytoma without anaplastic findings. Genetic analysis revealed loss of heterozygosity of 1p and 19q but not 10q, which is characteristic of oligodendroglial tumors. CONCLUSIONS:To our knowledge, this is only the second report describing primary oligoastrocytoma of the spinal cord. Genetic analysis may provide a clue in selecting optimal adjuvant therapies.  相似文献   
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993.
PURPOSE: To determine whether latanoprost lowers IOP in prostaglandin FP receptor knockout mice. METHODS: Mean IOP difference between treated and untreated fellow eyes was measured on three separate occasions, 2 hours after a 200-ng dose of latanoprost to the right eye of homozygous (n = 9) and heterozygous (n = 15) FP knockout mice. C57BL/6 (n = 10) and NIH Swiss white mice (n = 17), which have normal FP receptor expression, provided the control population. The investigator was masked to the genotype of the FP knockout mice at the time of IOP measurement. RESULTS: Latanoprost had no effect on IOP in the homozygous FP knockout mice, with an average difference in IOP between treated and untreated fellow eyes of +0.25 mm Hg and a 95% confidence interval (CI) for the difference between means of -0.019 to +0.69. In contrast, latanoprost reduced IOP in the treated eye of the heterozygous FP knockout, C57BL/6, and Swiss white mice with mean differences and 95% CI of the difference in means of -0.52 (-0.91 to -0.14), -1.38 (-2.1 to -0.70), and -1.29 (-1.78 to -0.79) mm Hg, respectively. CONCLUSIONS: FP receptor signaling plays a crucial role in the early IOP response to latanoprost in the mouse eye.  相似文献   
994.
BACKGROUND: The diagnosis of mucosa-associated lymphoid tissue (MALT) lymphoma in the intestine is occasionally difficult from histological examination on small biopsy specimens obtained by endoscopy. This study focused on unusual cases of reactive lymphoproliferative disorders in the intestine in order to make a differential diagnosis of MALT lymphoma. MATERIALS AND METHODS: Five patients were examined with regards to clinical symptoms, endoscopic findings and multiparameter analysis (the morphological examination using routine hematoxylin and eosin staining by light microscopy, immunophenotyping by flow cytometry (FCM), immunohistochemistry and genotyping of extracted DNA). RESULTS: All cases showed an aggregation of lymphocytes and one case showed similar features to lymphoepithelial lesions. Analyses of FCM and genetic rearrangements denied the monoclonality in all cases. Consequently, we considered that all cases should be diagnosed as reactive lymphoid hyperplasia and inflammatory change. CONCLUSION: Multiparameter analysis is useful in making an exact diagnosis of MALT lymphoma and therefore contributes to prevent unnecessary overtreatment.  相似文献   
995.
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997.
We examined the effects of neonatal treatment with MK-801 on 1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI)-induced head shaking as well as [(3)H]ketanserin binding in adult rats. Neonatal rats were injected with MK-801 (0.25 mg/kg, s.c., twice daily) or with saline from postnatal days (PND) 7-18. At PND 60, a statistically significant increase in the frequency of head shaking induced by DOI (1.0 mg/kg, s.c.) was observed in the rats neonatally treated with MK-801, compared to saline-treated rats, without any change in the specific [(3)H]ketanserin binding in the frontal cortex. These results suggest that repeated NMDA receptor blockades during the critical period of brain development produce a long lasting hyper-responsiveness in the 5-HT(2A) receptor-mediated behavior, interfering with the development of neural circuits related to the behavior.  相似文献   
998.
Individuals with inflammatory bowel disease (IBD) are at increased risk of developing gastrointestinal cancer. Here, we have tested the possibility that chronic inflammation could trigger mutations. For this, we have used IL-10-deficient (IL-10-/-) mice, which spontaneously develop intestinal inflammation, in combination with a transgenic gpt gene and red/gam gene (gpt+IL-10-/-), which is a well-characterized mutation reporter locus. The total mutation frequency in the colon of gpt+IL-10-/- mice was about five times higher than that in normal gpt+IL-10+/+ mice. In the particular case of G:C to A:T transitions, the frequency of mutations in gpt+IL-10-/- mice was 4.1 times higher than that in control mice. Interestingly, the frequency of small deletions and insertions was also strikingly increased (approximately 10 times). The majority of the deletion or insertion mutations were observed in the monotonous base runs or adjacent repeats of short tandem sequences. In contrast, the frequency of large deletions, detected by loss of the Spi marker present in the red/gam transgene, was similar among the mouse strains. Finally, as a control, the mutation frequency in non-inflamed tissues, such as the liver, were similar between gpt+IL-10-/- mice and gpt+IL-10+/+ mice. Our data demonstrate that the chronic inflammatory environment in the colon promotes the generation of mutations.  相似文献   
999.
Cerebral infarction results in multiple symptoms including hemiplegia and cognitive disturbances. The central nervous system has a limited capacity for self-repair, thus there is a great interest in the possibility of repairing the central nervous system by neural transplantation. Two different types of cerebral infarction model are well investigated for neural transplantation. Several kinds of donor cells have been used to try to restore the brain damage after ischemic insult. Reconstruction of neural circuits by transplantation is an ideal goal for the treatment of cerebral infarction, but trophic action of transplantation is also expected. Amelioration of ischemia-induced brain damage and recovery of neural dysfunction are documented. However, there are several factors and problems to be solved for clinical application.  相似文献   
1000.
Spur cell anemia, a hemolytic anemia observed in patients with alcoholic cirrhosis, is characterized by unusual erythrocyte morphology and an increased ratio of free cholesterol to phospholipid in the erythrocyte membrane. The prognosis of spur cell anemia is usually extremely poor, however, we describe here a patient with spur cell anemia who was successfully treated with combination therapy consisting of flunarizine, pentoxifylline, and cholestyramine. Initial therapy with flunarizine alone for 6 weeks did not significantly decrease the number of spur cells on peripheral blood smears. So pentoxifylline was added to the regimen. The patient recovered from the anemia, showed remarkable improvement with regard to the hyperbilirubinemia, and the changes were accompanied by a significant decrease in the number of spur cells in peripheral blood smears. To correct the hypercholesterolemia, cholestyramine was added to the regimen, which resulted in a reduction in the serum level of free cholesterol and an increase in the molar ratio of free cholesterol to phospholipid in erythrocyte membrane. However, 6 months later a skin eruption developed that was considered an adverse reaction to the drugs, so the flunarizine and pentoxifylline were discontinued. With cholestyramine therapy alone, the remission of spur cell anemia was maintained for more than 11 months. These observations suggest that non-invasive combination therapy with flunarizine, pentoxifylline, and cholestyramine is effective and valuable in the treatment of patients with spur cell anemia.  相似文献   
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