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41.
Lethal midline granuloma (LMG) is associated with Epstein-Barr virus (EBV). The latter has at least two subtypes with different biological properties. The subtypes can be identified by their genomic configuration. Using EBV-RNA (EBER) in situ hybridization and EBV polymerase chain reaction (PCR), we have looked for the presence of EBV in six LMGs and six non-Hodgkin's lymphomas (NHLs) located in the nasopharyngeal region, and determined the subtype of EBV. Six of six LMGs were positive by PCR and EBER in situ hybridization, whereas NHLs were either negative or, in three of six cases, showed few EBER- positive cells considered to be nonneoplastic lymphocytes. The subtype 2 was found in LMG lesions of three of six patients; the remaining three of six patients with LMG had the generally occurring subtype 1. The results indicate that the association of EBV with NHL may depend more on tumor type than on its localization. The occurrence of the rare subtype 2 in LMG may relate to a covert immune defect. 相似文献
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High levels of committed erythroid and granulocytic/monocytic progenitor cells have been demonstrated in fresh blood obtained at fetoscopy. The fetal progenitor cells were more sensitive to appropriate stimuli (erythropoietin and colony-stimulating factor) than adult progenitor cells grown under the same conditions, and this was shown to be due to intrinsic differences in the progenitor cells at the different developmental stages. 相似文献
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THOMAS MODÉER GÖRAN DAHLLÖF JOHAN KARSTEN PER OTTESKOG 《European journal of oral sciences》1989,97(2):186-187
Abstract – Human mononuclear cells purified by Lymphoprep flotation were incubated with phenytoin (PHT) (20 μg/ml) or its metabolite p-HPPH (2 μg/ml) in the presence of Concanaval-in A (10 μg/ml) in vitro. The results indicate that phenytoin and its metabolite p-HPPH induce the release of a mononuclear cell factor(s) that activates quiescent human gingival fibroblast to synthesize DNA. 相似文献
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Digital subtraction angiography (DSA) of the spinal cord was performed in 6 patients using selective intra-arterial injections of contrast material. Two arteriovenous malformations of the spinal cord, 1 dural fistula, and 1 case of multiple hemangioblastomas were studied. Contrast and spatial resolution were satisfactory for defining normal and abnormal vascularity while reducing examination time, contrast dosage, patient discomfort, and film cost. The only significant limitation was misregistration artifacts seen on lateral views encompassing the diaphragm. 相似文献
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EN Smit JM Dijkstra TA Schnater E Seerat FAJ Muskiet ER Boersma 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(7):690-695
Abstract Erythrocyte fatty acids and plasma vitamin E concentrations were determined in 47 grade 2 and 21 grade 3 malnourished Pakistani children (ages 4–56 months). Data were compared with those of 26 age- and sex-matched apparently healthy controls. Evaluation with three statistical approaches revealed that both grade 2 and grade 3 malnourished children had decreased erythrocyte ω6 fatty acids and to a lesser extent decreased ω3 fatty acids. These decreases were compensated for by increased ω9 fatty acids. The patients tended to have lower plasma vitamin E concentrations. We conclude that malnourished Pakistani children have low essential fatty acid status, notably those of the ω6 series. The combination of low erythrocyte 22:6ω3 and a low 22:5ω6/22:4ω6 ratio in grade 2 patients suggests low Δ4-desaturation activity, which may be due to impaired peroxisomal β-oxidation. 相似文献
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