凝集素美洲商陆和IL-2共同激活的单核细胞抗白血病作用的研究

采用MTT法研究了美洲商陆(PWM)和IL-2共同激活的单核细胞对人类白血病原代培养细胞的体外杀伤作用。结果表明,激活的单核细胞对白血病细胞具有明显的杀伤作用,其杀伤活性可达73.39％-83.73％。杀伤活性的强弱与白血病的细胞类型没有必然的联系;此外,来源于不同个体的白血病细胞对单核细胞杀伤作用的敏感性不同。采用激活的单核细胞对自体骨髓进行净化,用于造血干细胞移植,具有干细胞损失少,净化效果好,毒副作用小等特点,其应用前景良好。     

模糊-PI控制在血液透析机温度控制中的应用

目的:设计一种应用于血液透析机的温度控制系统。方法:提出了一种基于模糊控制和PI控制相结合的方法,在偏差较大时采用模糊控制算法,偏差较小时采用PI控制算法来调节PWM的占空比,从而调节加热棒的功率,实现对血液透析机的温度控制。结果:模糊-PI控制下系统温度超调为0.5%,稳态误差为±0.2℃,控制调整时间约为2 min。结论:该控制方法响应速度快、超调量小、稳态精度高,具有良好的动态性能和稳定度,实现对透析液温度的精确控制。     

Evaluation of T and B lymphocyte function in clinical practice using a flow cytometry based proliferation assay

The golden standard for functional evaluation of immunodeficiencies is the incorporation of [³H]-thymidine in a proliferation assay stimulated with mitogens. Recently developed whole blood proliferation assays have the advantage of parallel lymphocyte lineage analysis and in addition provide a non-radioactive alternative. Here we evaluate the Flow-cytometric Assay for Specific Cell-mediated Immune-response in Activated whole blood (FASCIA) in a comparison with [³H]-thymidine incorporation in four patients with severe combined immunodeficiency. The threshold for the minimum number of lymphocytes required for reliable responses in FASCIA is determined together with reference values from 100 healthy donors when stimulated with mitogens as well as antigen specific stimuli. Finally, responses against PWM and SEA + SEB stimuli are conducted with clinically relevant immunomodulatory compounds. We conclude that FASCIA is a rapid, stable and sensitive functional whole blood assay that requires small amounts of whole blood that can be used for reliable assessment of lymphocyte reactivity in patients.     

旋转式组织工程生物反应器检测控制及驱动系统

目的 生物反应器是组织工程的重要载体,旋转式生物反应器是目前研究的热点.本文探讨了可提供优良环境条件的可控生物反应器系统的设计与实践.方法 系统采用PWM可调驱动直流电机等;同时可对温度等物理量进行检测,并反馈控制调节反应器;测控系统与PC连接,可实现远程视频监测控等,使整个组织生物反应器系统初步实现了分步式、自动化.结果 经实验系统培养所得到的细胞相对于一般培养细胞其生物学特性有相当的改善.结论自动化旋转式生物反应器驱动控制的实践具有较大的应用推广价值.     

消化道无创诊疗微系统的无线供能技术的研究

报道了一种消化道微创诊疗微系统的无线体外供能装置,它主要由利用锁相环的自动频率跟踪电路和采用移相的调功电路构成。实验表明,该供能装置能自动频率跟踪和调节输出功率,使接收能量稳定。     

Toll-like receptor signaling in neonatal sepsis and inflammation: a matter of orchestration and conditioning

Altered neonatal Toll-like receptor (TLR) function is hypothesized to contribute to the heightened susceptibility to infection and perpetuated inflammation in term and preterm neonates, clinically evident in neonatal sepsis and increased rates of inflammatory disorders. Current data indicate that basal TLR expression in term neonates equals adult expression patterns, while expression in preterm infants seems to increase, depending on gestational age. Regarding TLR signaling, some studies suggest TLR incompetence in neonates associated with impaired pro-inflammatory responses, others describe neonatal TLR function well developed and allude to its hyper-inflammation tendency. We discuss the competing positions and considerable limitations of research approaches and conclude that neonatal innate immunity is not generally less able to respond to TLR stimulation. Moreover, we describe pre-conditioning factors other than immaturity having a comparable impact. In the long term, better understanding of the complex interplay of pre- and postnatal conditions and maturation-dependent neonatal TLR function may provide new therapeutic approaches.     

Temperature prediction in high speed bone grinding using motor PWM signal

This research explores the feasibility of using motor electrical feedback to estimate temperature rise during a surgical bone grinding procedure. High-speed bone grinding is often used during skull base neurosurgery to remove cranial bone and approach skull base tumors through the nasal corridor. Grinding-induced heat could propagate and potentially injure surrounding nerves and arteries, and therefore, predicting the temperature in the grinding region would benefit neurosurgeons during the operation. High-speed electric motors are controlled by pulse-width-modulation (PWM) to alter the current input and thus maintain the rotational speed. Assuming full mechanical to thermal power conversion in the grinding process, PWM can be used as feedback for heat generation and temperature prediction. In this study, the conversion model was established from experiments under a variety of grinding conditions and an inverse heat transfer method to determine heat flux. Given a constant rotational speed, the heat conversion was represented by a linear function, and could predict temperature from the experimental data with less than 20% errors. Such results support the advance of this technology for practical application.     

柯达DR7500悬吊系统独立PC与气弹簧的应用研究

目的：对柯达DR7500悬吊系统独立PC与气弹簧进行应用研究,准确快速制定安全有效的平衡方案。方法：利用数字技术,将运动力学信号转化成电信号,通过电路参数调整平衡。结果：减少了气弹簧衰减或失效对控制系统的损坏及医疗纠纷。结论：改进后提高了其临床检查的准确性,减轻了放射技术人员的负担,降低了维修费用,促进了医院的发展。     

Antibody producing human-human hybridomas. I. Technical aspects

Technical aspects of generation of antibody-secreting human-human hybridomas are evaluated as based on 100 human-human fusions with a human B-lymphoma cell line (RH-L4) or the SKO-007 myeloma cell line as malignant fusion partners, and compared with similar fusion conditions in the mouse hybridoma system. The yield of hybrids was significantly lower when normal peripheral blood lymphocytes were used as fusion partners as compared with spleen lymphocytes, but could be substantially improved by increasing the amount of mitotic active B-lymphocytes by mitogen stimulation of the lymphocytes, preferably in HAT medium, prior to fusion. Furthermore, human hybrids grew slower and had a higher degree of chromosomal instability than usually observed in the mouse hybridoma system. Thus, out of 72 fusions, only 3 stable hybrids with antibody production against a predefined antigen were established. The importance of improved sources of human B-lymphocytes for human-human hybridoma production is discussed and methods of obtaining such improvement suggested.     

Induction of immunoglobulin-producing human peripheral blood lymphocytes in serum-free medium

Induction of immunoglobulin-secreting cells from human peripheral blood lymphocytes in a serum-free culture medium was studied. Albumin, transferrin, insulin and fibronectin can replace serum entirely for support of pokeweed mitogen (PWM)-stimulated B lymphocytes, measured by a reverse hemolytic plaque assay using protein A-coated red cells. In this serum-free system, growth and maturation to IgM and IgG secretion occur at the same or higher efficiency as in conventional serum-containing medium, with maximum numbers of plaque-forming cells on day 6 at optimal dose of PWM, 0.5 ～ 5 μg/ml. This system can be used to avoid the interference from undefined serum components.