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51.
BACKGROUND: Non-myeloablative allogeneic stem cell transplantation followed by immunomodulatory therapies is considered a potentially curative approach in the treatment of multiple myeloma and most effective in a minimal residual disease setting. PATIENTS AND METHODS: The aim of this study was to find the most sensitive real-time PCR assay (TaqMan), based on the IGH rearrangement, to quantify the tumour load of 11 patients with multiple myeloma after non-myeloablative allogeneic transplantation. Patient-allele specific primers (ASO) and the TaqMan probe were derived from CDR2 and CDR3 hypervariable regions of IGH, while consensus primers were located within the FR3 and FR4/JH regions. Four different approaches of primer combinations were tested. RESULTS: ASO-forward and -reverse primers together with the clone-specific TaqMan probe were the most sensitive approach compared with the JH (P=0.071) or the FR3 consensus primer (P <0.001). The detection limit amounted to 1/10(4)-1/10(5) cells. Consecutively, 120 samples from 11 patients prior and post allogeneic transplantation were analysed. Three patients reached complete clinical remission accompanied by molecular remission. Disease progression or relapse was seen in six patients. In five, molecular progressive disease was detected prior to the clinical diagnosis of progression or relapse. CONCLUSION: Patient-specific real-time IGH-PCR provides the opportunity for earlier treatment intervention.  相似文献   
52.
细辛脑中有机溶剂残留的固体顶空毛细管GC测定   总被引:20,自引:0,他引:20  
建立了固体顶空毛细管气相色谱法测定细辛脑中有机溶剂残留量.采用DB-1大口径毛细管柱,以正丙醇为内标.甲醇、乙醇、二氯甲烷、正己烷、甲苯的回收率分别为102.5%、103.7%、96.1%、91.4%和92.9%,检测限分别为0.02、0.02、0.02、0.01和0.02μg/g.  相似文献   
53.
建立了毛细管气相色谱法测定乙酸奥曲肽中有机溶剂乙醚、甲醇、二氯甲烷、N,N-二甲基甲酰胺的含量.用HP-Innowax毛细管柱,程序升温的方法.各组分的线性范围分别为25~300、25~300、15~180和25~300μg/ml(r均大于0.999).平均回收率分别为99.7%、99.5%、99.3%和99.2%.检测限分别为1、1、0.6和1ng.  相似文献   
54.
建立了毛细管气相色谱法测定兰索拉唑中甲醇、丙酮、乙腈、氯仿的残留量.采用RTX-50毛细管柱,程序升温.各溶剂检测限分别为18、50.4、1.46和0.4ng,平均回收率分别为102.3%、100.4%、101.8%和1013%.  相似文献   
55.
顶空气相色谱法检测百乐眠胶囊中树脂残留物   总被引:6,自引:2,他引:6  
张玉斌  徐玉凤 《中国药事》2004,18(4):236-237
建立气相色谱法检测百乐眠胶囊中树脂残留物的方法.采用气相色谱法对百乐眠胶囊中苯、甲苯、二甲苯、正己烷、苯乙烯、1,4-二乙苯的残留量进行检测,气相色谱条件为:色谱柱HP-5,载气为高纯氮气,柱前压为10Psi,气化室温度200℃,柱温60℃(5min),以30℃*min-1的速率升至90℃(3.5min),再以30℃*min-1的速率升至140℃(4min),最后以30℃*min-1的速率升至190℃(3min),检测器为FID,温度为220℃.正己烷在1.815~29.060μg*ml-1,苯在0.0128~0.1966μg*ml-1内,甲苯在0.685~11.125μg*ml-1内,二甲苯在1.698~27.170μg*ml-1内,苯乙烯在1.695~27.125μg*ml-1内,1,4-二乙苯在1.699~27.140μg*ml-1内均有良好的线性关系,相关系数分别为0.9996、0.9991、0.9996、0.9998、0.9966、0.9980.本法简便、快速、准确度高,适于测定百乐眠胶囊中树脂残留物,可作为百乐眠胶囊的质量监控方法.  相似文献   
56.
顶空气相色谱法测定盐酸依匹斯汀中溶剂残留   总被引:26,自引:3,他引:26  
建立顶空气相色谱法分析盐酸依匹斯汀中溶剂残留.采用DB-1大口径毛细管柱,以正丙醇为内标进行定量.甲醇、乙醚、三氯甲烷、四氢呋喃的线性范围分别为7.9 ~ 317.0μg·ml-1 (r=0.9996),0.7~35.5μg·ml-1(r=0.9998),1.5~73.5μg·ml-1 (r=0.9992),0.9~44.4μg·ml-1(r=0.9994),回收率分别为101.64%,97.18%,99.32%,101.12%,RSD分别为1.97%,1.10%,2.40%,0.84%.本方法简单、准确、灵敏度高、重现性好.  相似文献   
57.
58.
The laser shock peening (LSP) process using a Q-switched pulsed laser beam for surface modification has been reviewed. The development of the LSP technique and its numerous advantages over the conventional shot peening (SP) such as better surface finish, higher depths of residual stress and uniform distribution of intensity were discussed. Similar comparison with ultrasonic impact peening (UIP)/ultrasonic shot peening (USP) was incorporated, when possible. The generation of shock waves, processing parameters, and characterization of LSP treated specimens were described. Special attention was given to the influence of LSP process parameters on residual stress profiles, material properties and structures. Based on the studies so far, more fundamental understanding is still needed when selecting optimized LSP processing parameters and substrate conditions. A summary of the parametric studies of LSP on different materials has been presented. Furthermore, enhancements in the surface micro and nanohardness, elastic modulus, tensile yield strength and refinement of microstructure which translates to increased fatigue life, fretting fatigue life, stress corrosion cracking (SCC) and corrosion resistance were addressed. However, research gaps related to the inconsistencies in the literature were identified. Current status, developments and challenges of the LSP technique were discussed.  相似文献   
59.
Depression is increasingly prevalent in Western countries. It has severe consequences and is associated with increased rates of disability, morbidity, and mortality. Despite numerous therapeutic options, a great number of depressed patients do not achieve full remission. In addition, despite good short-term outcomes, long-term therapeutic results remain disappointing and associated with a poor prognosis, raising significant concern in terms of public health. Impaired sleep – especially insomnia – may be at least partly responsible for this problem. Very close relationships between major depressive disorder (MDD) and sleep disorders have been observed. In particular, residual symptoms of sleep disturbance in a remitted patient may predict a relapse of the disease. However, most currently available antidepressants do not always take into consideration the sleep disturbances of depressed patients; some agents long used in clinical practice even appear to worsen them by their sleep-inhibiting properties. But some other new medications were shown to relieve early sleep disturbance in addition to alleviating other depression-related symptoms. This positive impact should promote compliance with medication and psychological treatments, and increase daytime performance and overall functioning. Complete remission of MDD appears therefore to depend on the relief of sleep disturbances, a core symptom of MDD that should be taken into consideration and treated early in depressed patients.  相似文献   
60.
Friction Stir Welding (FSW) is a solid-state joining process; i.e., no melting occurs. The welding process is promoted by the rotation and translation of an axis-symmetric non-consumable tool along the weld centerline. Thus, the FSW process is performed at much lower temperatures than conventional fusion welding, nevertheless it has some disadvantages. Laser Assisted Friction Stir Welding (LAFSW) is a combination in which the FSW is the dominant welding process and the laser pre-heats the weld. In this work FSW and LAFSW tests were conducted on 6 mm thick 5754H111 aluminum alloy plates in butt joint configuration. LAFSW is studied firstly to demonstrate the weldability of aluminum alloy using that technique. Secondly, process parameters, such as laser power and temperature gradient are investigated in order to evaluate changes in microstructure, micro-hardness, residual stress, and tensile properties. Once the possibility to achieve sound weld using LAFSW is demonstrated, it will be possible to explore the benefits for tool wear, higher welding speeds, and lower clamping force.  相似文献   
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