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JM Buesa A López-Pousa J Martín A Antón J García del Muro J Bellmunt F Arranz V Valentí P Escudero D Menéndez A Casado A Poveda 《Canadian Metallurgical Quarterly》1998,9(8):871-876
BACKGROUND: The agent Ifosfamide (IFOS) is active against soft tissue sarcomas (STS), and patients who progress to IFOS at doses < or = 10 g/m2 show remissions when exposed to high-dose ifosfamide (HDI) (i.e., doses > 10 g/m2), which supports a dose-response relationship for this drug. Because of a lack of first-line studies in adult STS patients, we decided to test the activity and toxicity of HDI in a phase II trial. PATIENTS AND METHODS: Forty-eight patients were enrolled in the study. IFOS was administered at a dose of 14 g/m2 by continuous infusion over six days every four weeks. Granulocyte-macrophage colony-stimulating factor (GM-CSF) at 5 micrograms/kg/day for 10 consecutive days was systematically administered after an episode of neutropenic fever or a delay in hematologic recovery. Patients were treated until progression or the occurrence of severe toxicity, and surgical rescue was attempted when possible. RESULTS: Six pathology-established complete remissions and 11 partial remissions were observed in 45 assessable patients with a response rate of 37.7% (95% CI: 25.5%-50%). Grade 3-4 toxicity (% of cycles) was noted by hemoglobin (17%), leukocyte (75%), granulocyte (75%) and platelet (13%) counts in 158 evaluable cycles. GM-CSF was administered to 28 patients, and 25 suffered one or more episodes of neutropenic fever. Renal toxicity was mild and reversible with some degree of tubular and glomerular dysfunction detected in up to 60% of patients. Grade 3 CNS toxicity was observed in 32% of patients but only one required interruption of therapy. Sixty-four per cent of the patients had asthenia grade 2-3 and 20% were excluded from the study due to excessive toxicity. There was one treatment-related death. CONCLUSIONS: HDI is an active drug in first-line therapy against adult STS. Different administration schedules should be evaluated in an attempt to improve its therapeutic index. 相似文献
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I. J. Ferrer C. De Las Heras N. Menéndez J. Tornero C. Sánchez 《Journal of Materials Science》1993,28(2):389-393
Mössbauer spectroscopy has been used to analyse FeS2 thin films obtained by sulphidation of 57Fe evaporated layers. Complementary characterization of the films has been carried out by X-ray diffraction and optical absorption measurements. It is concluded that the two processes (formation and crystallization of FeS2) which lead to polycrystalline FeS2 films are strongly influenced by the temperature at which sulphidation is accomplished. The composition of the films drastically changes at temperatures which depend on the thickness of the Fe film to be sulphidated, and their crystallization seems to show a critical temperature at which the crystallization process is severely altered. Optical properties of the pyrite films seem to depend strongly on their stoichiometry. 相似文献
137.
标准气体微流量计的性能测试 总被引:1,自引:1,他引:0
主要介绍标准微流量计的性能测试。测试结果表明;气体流量的测量范围为17.1×10-5~1.22×10-5pa·L/s,不确定度小于2%。 相似文献
138.
门乃姣 《水利水电工程设计》2006,25(1):10-12,19
龙口水利枢纽工程设计过程中,充分考虑了各方面因素,合理利用地形和地质条件,解决了狭窄河道多建筑物枢纽总体布置、多泥沙河流排沙及大流量泄洪消能设施设计等问题,并经整体水工模型试验验证设计方案合理、切实可行。 相似文献
139.
本文详细分析了现有输入噪声模型和输出噪声模型的抗噪声原理,提出了一种能同时抑制输入噪声和输出噪声的无偏差估计模型,它利用二次互功率谱代替通常估计中的自功率谱。使得由于噪声引起的误差可以通过多次平均完全消除。新估计模型的精度与输入噪声和输出噪声的水平无关,仅与统计次数有关。在输入、输出噪声不相关条件下,即使相干函数很低仍能通过多次平均获得具有足够精度的频响函数值。文章最后给出了不同噪声干扰下的(?)估计值、(?)估计值以及本文模型的(?)估计值,并与没有噪声干扰下的H_o 值进行比较。 相似文献
140.
P Johansen Y Men R Audran G Corradin HP Merkle B Gander 《Canadian Metallurgical Quarterly》1998,15(7):1103-1110
PURPOSE: Tetanus toxoid (Ttxd) encapsulated in polyester microspheres (MS) for single injection immunization have so far given pulsatile in vitro release and strong immune response in animals, but no boosting effect. This has been ascribed to insufficient toxoid stability within the MS exposed to in vivo conditions over a prolonged time period. This study examined the effect of co-encapsulated putative stabilizing additives. METHODS: Two different Ttxd were encapsulated in poly(D,L-lactic-co-glycolic acid) (PLGA 50:50) and poly(D,L-lactic acid) (PLA) MS by spray-drying. The influence of co-encapsulated additives on toxoid stability, loading in and release from the MS, was studied by fluorimetry and ELISA. RESULTS: Co-encapsulated albumin, trehalose and gamma-hydroxypropyl cyclodextrin all improved the toxoid encapsulation efficiency in PLGA 50:50 MS. Albumin increased the encapsulation efficiency of antigenic Ttxd by one to two orders of magnitude. Further, with albumin or a mixture of albumin and trehalose ELISA responsive Ttxd was released over 1-2 months following a pulsatile pattern. CONCLUSIONS: Optimized Ttxd containing MS may be valuable for a single-dose vaccine delivery system. 相似文献