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21.
SM Kornblau E Estey T Madden HT Tran S Zhao U Consoli V Snell G Sanchez-Williams H Kantarjian M Keating RA Newman M Andreeff 《Canadian Metallurgical Quarterly》1997,15(5):1796-1802
PURPOSE: Expression of the multidrug resistance gene (MDR1) p170 protein is frequent in leukemic blasts from patients with relapsed acute myelogenous leukemia (AML). A phase I study using the nonimmunosuppressive MDR1 blocker SDZ PSC-833 (PSC) in combination with mitoxantrone (MITO) and etoposide (VP) was performed. PATIENTS AND METHODS: Starting doses (LVL0) of MITO (3.25 mg/m2/d on days 1 and 3 to 6) and VP (210 mg/m2/d on days 1 and 3 to 5) were 40% of the maximal-tolerated dose (MTD) from a prior study. A 1.5-mg/kg loading dose of PSC was followed by a 120-hour continuous infusion of 10 mg/kg/d on days 2 to 6. Blood samples for PSC, MITO, and VP pharmacokinetics (PK) were taken on days 1 and 3, and samples for MDR1 expression were taken on day 0. RESULTS: Severe mucositis developed in all patients at LVL0; therefore, MITO and VP doses were reduced to 2.5 and 170 mg/m2 (LVL-1) for the next seven patients, and this dose proved to be MTD. All LVL0 and three LVL-1 patients had transient elevations in the serum bilirubin level to > or = 4 mg/dL. Serum creatinine level increased to greater than 2 mg/dL in one case. There were no other grade 3 or 4 nonhematologic toxicities observed. The peripheral blood was cleared of leukemia in three LVL0 and four LVL-1 patients. The marrow was cleared of leukemic cells in one LVL0 and five LVL-1 patients, and a significant reduction in marrow leukemic infiltrate was observed in eight of 10. No patient achieved complete remission (CR), and all died of progressive disease (n = 8) or infection (n = 2). MDR1 expression was detected by fluorescent-activated cell sorter (FACS) analysis in five of seven cases. An elevated MDR1 mRNA level was detected by quantitative polymerase chain reaction (Q-PCR) in six of eight cases studied. Clearing of leukemia cells from the marrow occurred in four of six MDR1-positive and one of three MDR1-negative patients. Despite the fact that LVL0 doses had to be reduced due to toxicity, coadministration of PSC did not produce a consistent effect on MITO PK; however, it did repeatedly lead to increased levels of VP in the serum. CONCLUSION: We conclude that PSC-MITO-VP is a tolerable regimen with antileukemic activity. Addition of PSC necessitated a 66% reduction in MITO and VP doses from a prior study without PSC. 相似文献
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Restless legs syndrome affects millions, but most healthcare providers don't know it exists. Its sleep-deprived victims are plagued by indescribable crawling sensations in their legs that occur at night and that are only relieved by moving the legs. Many home healthcare clients, already challenged by their primary illness, are also affected by the persistent symptoms of Restless Legs Syndrome. It is important that home care nurses learn about Restless Legs Syndrome-what it is, how to assess it, and what can be done about it. 相似文献
24.
本文基于静态相关性分析和动态调整相结合的方法,提出了一种逻辑程序的执行模型,它不仅开发了“与“并行,同进也开发了一定的“或“并行,从而有效地加速了逻辑程序的执行。 相似文献
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重馏分油加氢脱氮反应动力学模型的研究 总被引:10,自引:1,他引:9
简要地介绍了一些典型的模型氮化物的HDN反应规律。根据胜利VGO在3722B催化剂上的大量HDN实验数据,提出了如下的HDN基本反应动力学方程:dCNdt=-k1+K*CNCNPH2为了扩大上式的应用范围,详细分析了各种因素(如原料油种类和馏程及H2S等)对HDN的影响,并开发了相应的经验关联式,从而得到了一个较完整的馏分油HDN反应动力学模型。验证实验表明,该模型是成功的。 相似文献
27.
HE Montgomery P Clarkson CM Dollery K Prasad MA Losi H Hemingway D Statters M Jubb M Girvain A Varnava M World J Deanfield P Talmud JR McEwan WJ McKenna S Humphries 《Canadian Metallurgical Quarterly》1997,96(3):741-747
PURPOSE: To determine the radiologic characteristics of cystic dystrophy of the duodenal wall. MATERIALS AND METHODS: Ten patients with cystic dystrophy of the duodenal wall and chronic pancreatitis underwent ultrasonography (US) (n = 10), computed tomography (CT) (n = 10), endoscopic US (n = 5), and endoscopic retrograde cholangiopancreatography (ERCP) (n = 9). Cystic dystrophy of the duodenal wall was classified as either cystic or solid. The imaging findings were retrospectively analyzed and compared with findings at pancreatoduodenectomy (n = 10). RESULTS: The more frequent cystic type (n = 7) of cystic dystrophy of the duodenal wall was characterized by the presence of easily recognizable cystic lesions (diameter, more than 1 cm), located within the thickened wall of the second portion of the duodenum. The solid type (n = 3) of cystic dystrophy of the duodenal wall demonstrated fibrous thickening of the duodenal wall within which small cysts (diameter, less than 1 cm) were present. The intraduodenal cysts were usually elongated or bilobate with a thick wall. The thickening of the duodenal wall appeared as a solid layer between the duodenal lumen and the pancreas, hypoechoic at US, isoattenuating at unenhanced CT, and hypoattenuating in the early phase (after initiation of infusion of contrast material) and isoattenuating in the late phase (after completion of infusion) at contrast material-enhanced CT. Findings at retrospective analysis of CT and endoscopic US images were characteristic. CONCLUSION: Imaging modalities, notably CT and endoscopic US, helped establish the diagnosis of cystic dystrophy of the duodenal wall. 相似文献
28.
潘家口小水电群在建设中需要在原有建筑物上拆除混凝土,须克服场地窄小,交通不便、设备安全、环保问题等困难。采用了行之有效的静、动态爆破方案,成功地从54个部位拆除钢筋混凝土1200多立方米,从而保证了小水电群建设投产。 相似文献
29.
A novel, heat-resistant and Pronase-sensitive, inhibitor of eukaryotic DNA topoisomerase I has been purified from Xenopus laevis ovaries. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the most purified fraction revealed three bands with apparent molecular masses of 25, 28.5, and 33.5 kDa. The 25- and 33.5-kDa peptides recovered from an SDS-PAGE gel inhibited X. laevis DNA topoisomerase I. The purified inhibitor was specific to DNA topoisomerase I and did not inhibit other DNA enzymes tested. The inhibitor blocked the catalytic activity of DNA topoisomerase I by interacting with the enzyme, rather than by competing for binding sites on substrate DNA. Binding of DNA topoisomerase I to substrate DNA was blocked by the inhibitor, as was the cleavage reaction catalyzed by DNA topoisomerase I. Inhibition of DNA topoisomerase I was relieved by divalent cations Ca2+, Mg2+, or Mn2+. 相似文献
30.