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31.
Neuroblastoma, along with rhabdomyosarcoma, Ewing's sarcoma, and acute lymphoblastic leukemia/lymphoma, is one of the small, round-cell tumors of childhood. All of these malignancies show a propensity to metastasize to bone marrow. Occasionally when the clinical picture is unclear and the tumor is particularly anaplastic, it can be difficult to arrive at a diagnosis by conventional histological and biochemical procedures. In the present study, a panel of nine monoclonal antibodies was used to undertake a detailed analysis of seven bone marrows contaminated with tumor cells: six cases of stage IV neuroblastoma, and one case of stage IV-S neuroblastoma. The antibody profiles obtained were compared with those deduced from the studies of over 20 marrows from patients with acute lymphoblastic leukemia. A comparison of these data with those obtained from the studies of rhabdomyosarcoma and Ewing's sarcoma cell lines and tissues suggests that when high levels of tumor cells are present in the marrow, it is possible to obtain a confident diagnosis of either neuroblastoma or acute lymphoblastic leukemia. In addition, the immunocytological identification of neuroblasts in bone marrow enables accurate staging without histological examination.  相似文献   
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The prenyl-phenol antibiotics ascochlorin-related compounds, are known to reduce serum cholesterol and triglyceride, suppress hypertension, and ameliorate types-I and II diabetes. However, little is known about the molecular mechanism for these physiological effects. Here we report that the ascochlorin derivative, 4-O-carboxymethyl ascochlorin (AS-6) acts as a potent activator of the nuclear hormone receptor, PPARgamma, although it does not activate the related receptors, PPARalpha, PPARdelta or RARalpha. AS-6 interacts directly with the PPARgamma molecule in vitro, and induces differentiation of the mouse preadipocyte cell line 3T3-L1. Our results suggest that AS-6 is a partial agonist for PPARgamma with a novel chemical structure.  相似文献   
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BACKGROUND: There are two main lymphatic routes from the lower extremity: the fibular route to the popliteal node and the tibial route to the distant groin node. However, little is known about lymphatics from the sole. OBJECTIVE: We attempted to obtain detailed knowledge of the lymphatics from the sole. METHODS: Eight patients with lymphangitis were examined and compared with the drainage patterns visualized by blue-dye injection in 7 cases of melanoma. RESULTS: Six lymphangitic streaks started from the lateral edge of the plantar surface, 2 from the heel, and 1 each from the center of the sole and the little toe. All streaks ran to the tibial side and went up along the foot branch of the great saphenous vein. These findings were similar to those of the dye-injected melanoma cases. CONCLUSION: Lymphangitis makes visualization of lymphatic routes possible and may provide useful information about drainage.  相似文献   
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Human T-cell-leukemia-virus-type-1 (HTLV-I) infection is associated with adult T-cell leukemia/lymphoma (ATL) and HTLV-1 -associated myelopathy (HAM)/tropical spastic paraparesis (TSP). The T-cell-targeting immunosuppressants, FK506 and cyclosporin A (CsA), suppressed proliferation of the HAM/TSP-derived T-cell lines, H89–59, H89–79 and H109. FK506 and CsA also reduced expression of the proto-oncogenes, c-myc and c-fos, but not c-jun and interleukin-2-receptor-α (IL-2Rα) gene in H109 cells. The growth-inhibitory effects of FKS06 and CsA were not abrogated by interleukin 2 (IL-2). These results suggest that the inhibitory effects of FK506 and CsA are independent of IL-2, and are associated with the reduction of c-myc and c-fos gene expression.  相似文献   
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Methyl n-butyl ketone (MBK) is known to produce a giant axonal neuropathy in man and experimental animals characterized pathologically by a gradual increase in the number of neurofilaments which become associated with focal areas of axonal swelling and thinning of the myelin sheath. Fast axoplasmic transport was studied in rats exposed to MBK. In 10 severely paralyzed rats exposed to MBK there was a significant impediment of fast axoplasmic transport following dorsal root ganglion injections (x +/- S.D. = 283.2 +/- 20.34 mm/day) compared to normal controls (417.6 +/- 23.78 mm/day). In rats undergoing injections into the ventral horn of the spinal cord there was a gradual impairment of the mean down flow rate for transport of [3H]leucine which correlated with the severity of the MBK induced neuropathy. Quantitative morphological determinations showed that the total number of neurotubules per unit cross-sectional myelin area and the number of neurotubules associated with mitochondria in swollen axons was unchanged from normal. The total number of mitochondria in randomly sampled axons varied significantly from controls but the absolute number of mitochondria associated with neurotubules was unchanged from normal. The results of these studies suggest that the impediment of fast axoplasmic transport may be related to the increased neurofilaments producing focal areas of axonal blockage.  相似文献   
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In order to elucidate the differences between systemic and central nervous system (CNS) immunity that are relevant to exacerbations of multiple sclerosis (MS), paired peripheral blood and cerebrospinal fluid (CSF) samples obtained from 36 non-treated patients with relapsing-remitting MS (RRMS) were simultaneously examined using flow cytometry to determine the percentages of functional lymphocyte subsets, as well as enzyme-linked immunosorbent assays for measuring soluble immune mediators.Active RRMS patients (n = 27) were characterized by an increase in CD4+ CXCR3+ Th1 cells in blood as compared with inactive patients (n = 9), and this parameter was inversely correlated with plasma levels of IL-10 and IL- 12p70. In contrast, an increase in the percentage of CD4+ CD25+ cells and a decrease in the percentage of CD8+ CD11a(high) cells were features of CSF samples from those with active RRMS. Further, CSF CD4+ CD25+ cells had a close association with leukocyte counts as well as albumin and CXCL10 levels in the CSF, and, thus, could be useful as a measure for inflammatory reactions in the CNS. On the other hand, CD8+ CD11a(high) cells may function as immunoregulatory cells, as their percentage in the CSF showed a positive correlation with CSF levels of the anti-inflammatory cytokine IL-4. These findings suggest that MS relapses occur in a combination with altered cell-mediated immunity that differs between the peripheral blood and CSF compartments, while measurement of lymphocyte subsets may be helpful for monitoring disease status.  相似文献   
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