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81.
The purpose of this study was to define, in a phase I study in leukemia, the maximally tolerated dose (MTD), major toxicities, and possible antitumor activity of Topotecan, a new topoisomerase I (topo I) inhibitor. Topotecan was delivered by a 5-day continuous infusion every 3 to 4 weeks to patients with refractory or relapsed acute leukemia, at doses ranging from 3.5 mg/m2 to 18 mg/m2 per course. Twenty-seven patients were treated, including 17 patients with acute myelogenous or undifferentiated leukemia, 7 with acute lymphocytic leukemia, and 3 with chronic myelogenous leukemia in blastic phase. Severe mucositis was the dose-limiting toxicity occurring in two of five patients treated with Topotecan 11.8 mg/m2 per course; a third patient had prolonged myelosuppression. At the MTD of 10 mg/m2 per course, 1 of 12 patients had severe mucositis and 5 had mild-to- moderate mucositis. Nausea, vomiting, diarrhea, and prolonged myelosuppression were uncommon. Three patients (11%) achieved a complete response, two (7%) had a partial response, and one (4%) had a hematologic improvement. The overall complete plus partial response rate was 19%, and 24% in acute myelogenous or undifferentiated leukemia. A novel in vitro assay that quantifies Topotecan-stabilized topo I-DNA complexes in patient samples was used, which demonstrated heterogeneity in the ability of Topotecan to interact with topo I, the intracellular target of Topotecan. This phase I study defined the MTD of Topotecan to be 10 mg/m2 by continuous infusion over 5 days every 3 to 4 weeks in patients with refractory or relapsed acute leukemia. Severe mucositis was the dose-limiting toxicity. Future studies will define the precise activity of Topotecan in different leukemia subsets, its efficacy in combination with other antileukemic drugs, and correlations between Topotecan-induced topo I-DNA complex formation and individual patient response to Topotecan.  相似文献   
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In the present study, we investigated the effect of interferon-alpha (IFN-alpha) on the expression of interleukin-10 (IL-10) mRNA and protein synthesis in human monocytes and CD4+ T cells. In mononuclear cells, IFN-alpha induced expression of IL-10 mRNA and further enhanced lipopolysaccharide (LPS)-stimulated IL-10 expression. In purified monocytes, a strong expression of IL-10 mRNA induced by LPS was not further enhanced by IFN-alpha. In highly purified CD4+ T cells, IFN- alpha upregulated IL-10 mRNA upon activation with phytohemagglutinin and phorbol myristate acetate. In purified monocytes, an effect of IFN- alpha on IL-10 protein synthesis was dependent on costimulation with LPS. Maximal stimulation of IL-10 protein by IFN-alpha was seen after prolonged incubation periods of 48 to 96 hours, whereas IFN-gamma reduced IL-10 production in the early incubation period. Similar effects of IFN-alpha were observed in CD4+ T cells activated with CD3 and CD28 monoclonal antibodies. Addition of IFN-alpha caused an increase of IL-10 in culture supernatants of activated T-helper cells of more than 100% after 96 hours of incubation. In contrast, other cytokines, including IFN-gamma and IL-4, had no influence on IL-10 secretion stimulated by CD3 and CD28 in CD4+ T cells. In serum samples of IFN-alpha-treated individuals, we failed to detect an influence of cytokine treatment on IL-10 serum levels, confirming the requirement of additional activating signals for IFN-alpha-mediated effects on IL-10 synthesis. In conclusion, IFN-alpha enhances the late induction of IL- 10, which physiologically occurs upon stimulation of monocytes and T cells. Biologically, this effect might enhance the negative-feedback mechanism ascribed to IL-10, which limits inflammatory reactions.  相似文献   
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Extramedullary multiple myeloma (EMM) involving the liver as a focal space‐occupying lesion is very rare, especially in the patients with cirrhosis. Here, we report a case of EMM in the liver and periportal lymph node, diagnosed by endoscopic ultrasound guided‐fine‐needle aspiration (EUS‐FNA). A 57‐year‐old male patient, with history of cirrhosis, presented with abdominal pain and pancytopenia. The abdominal magnetic resonance imaging (MRI) demonstrated a 6.5 cm left hepatic mass with a 1.1 cm malignant‐appearing periportal lymph node and diffuse osseous lesions. The cytology specimens from the hepatic mass and the periportal lymph node were obtained through EUS‐FNA without rapid on‐site evaluation (ROSE). The thin‐layer preparations (ThinPrep) showed abundant plasmacytoid cells, which were confirmed to be Kappa‐restricted neoplastic plasma cells by the cell block preparations. Later, his serum level of Kappa light chain was found significantly elevated by flow cytometry, which was identified as monoclonal IgA Kappa light chain by serum protein electrophoresis (SPEP) with immunofixation. The patient was diagnosed as IgA multiple myeloma with extramedullary involvement of the liver and periportal lymph node. This is the first case showing the ThinPrep cytomorphologic features of EMM in the liver and periportal lymph node. This case highlights the importance of distinguishing plasma cells from being hepatocytes and lymphocytes on the ThinPrep and also emphasizes the utility of the cell block in the diagnosis of plasma cell neoplasm.  相似文献   
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目的 与开腹胆囊切除术相比,腹腔镜胆囊切除术(LC)有减少术后不适和较少的创作,但仍有改进的余地。方法:为进一步减轻手术创伤,我们引进了针式腹间胆囊切除术,共29例。结果 平均手术时间为75分钟,19例当天出院,10例隔天出院,其中1例是胆总管探查。结论 针式航空 镜胆囊切除术是一种可靠的技术。  相似文献   
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0引言白血病免疫分型是指用已知的单克隆抗体(单抗)鉴定细胞表面或胞质内的分化抗原的方法.该方法的临床应用有利于白血病的鉴别及诊断.我们采用单人份免疫分型试剂盒对128例白血病患者进行了免疫分型.  相似文献   
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