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891.
The effect of foetal liver cells on GVH reaction with the parental lymphocytes in F1 hybrid mice was studied. The GVH reaction was induced in newborn (CBA X C3H)F1 and in 10-day-old (CBA X C57BL/6)F1 hybrid mice. Foetal liver cells did not induce a GVH reaction. The GVH reaction of CBA spleen cells in (CBA X C3H)F1 hybrid mice was demonstrable, although weak. Foetal liver cells suppressed the GVH reaction, in dependence on cell concentration, in (CBA x C3H)F1 but not in (CBA X C57BL/6)F1 hybrid mice. The possibility to induce transplantation tolerance with foetal liver cells is discussed. 相似文献
892.
GC Gast TH The H Schraffordt Koops AM Snijder HA Huiges 《Canadian Metallurgical Quarterly》1976,23(3):491-498
The primary immune response to Helix pamatia haemocyanin (HPH) was investigated in sixty-one patients with various clinical signs of malignant melanoma and compared to that of controls. Anti-HPH antibody response was only found abnormal in patients with widespread disease and visceral metastases, apparent from decreased 7S and increased 19S antibody levels. In vitro HPH-induced lymphocyte transformation, in contrast, was not only decreased in this late stage, but also in part of the patients in the beginning of the disease and was then correlated with subsequent tumour recurrence within 6 months. Generally, patients with positive lymphocyte transformation showed significantly higher 7S anti-HPH titres (mean 3-3 +/- 2-4 than patients without (1-7 +/- 1-6). In contrast to the lymphocyte transformation reaction, anti-HPH antibody response was not correlated with subsequent tumour recurrence. The same phenomenon of decreased 7S and increased 19S antibody response as in the melanoma patients with far advanced disease was observed to a less extent in controls with ageing. Anamnestic antibody responses to diphtheria and tetanus toxoid and serum IgG and IgA levels were found normal. Elevated serum IgM levels were more frequently observed in patients with localized (19/31) and disseminated disease (11/29) than in controls (2/31). These results suggest that melanoma patients develop impaired T-lymphocyte functions in final stages with visceral metastases. A previous study showed that minor defects in lymphocyte function in an early stage as measured by HPH-induced lymphocyte transformation have predictive value for subsequent tumour recurrence. 相似文献
893.
The key theorem and the bounds on the rate of uniform convergence of learning theory on Sugeno measure space 总被引:1,自引:0,他引:1
In the 1970s, Vapnik[1―3] proposed the Statistical Learning Theory (SLT), which deals mainly with the statistical learning principles when samples are limited. SLT is an im- portant development and supplement of traditional statistics, whose kernel idea … 相似文献
894.
Clancy Susan A.; McNally Richard J.; Schacter Daniel L.; Lenzenweger Mark F.; Pitman Roger K. 《Canadian Metallurgical Quarterly》2002,111(3):455
False memory creation was examined in people who reported having recovered memories of traumatic events that are unlikely to have occurred: abduction by space aliens. A variant of the Deese/Roediger-McDermott paradigm (J. Deese, 1959; H. L. Roediger III & K. B. McDermott, 1995) was used to examine false recall and false recognition in 3 groups: people reporting recovered memories of alien abduction, people who believe they were abducted by aliens but have no memories, and people who deny having been abducted by aliens. Those reporting recovered and repressed memories of alien abduction were more prone than control participants to exhibit false recall and recognition. The groups did not differ in correct recall or recognition. Hypnotic suggestibility, depressive symptoms, and schizotypic features were significant predictors of false recall and false recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
895.
Persons with chronic pain often report a range of physical symptoms beyond their primary pain complaint itself. We predicted that non-specific physical symptom complaints would correlate more strongly with pain-related distress than with general measures of distress, and that they would contribute directly to disability. Results from 210 adults with chronic pain showed that collateral physical complaints are common in persons with chronic pain. Correlational analyses showed that greater reporting of physical complaints was associated with reports of higher pain severity, higher levels of depression, more cognitive, escape/avoidance, fearful appraisal, and physiological symptoms of pain-related anxiety and more physical and psychosocial disability. Regression analyses showed that, with pain-related anxiety variables entered either before or after depression, physiological symptoms of pain-related anxiety significantly predicted physical complaints. In comparison with cognitive and somatic depression symptoms physiological symptoms of pain-related anxiety were the stronger predictor. 相似文献
896.
897.
铝双层板结构撞击损伤的板间距效应实验研究 总被引:1,自引:0,他引:1
为了研究空间碎片对航天器防护结构的超高速撞击损伤特性,采用二级轻气炮发射球形弹丸,对铝双层板结构进行了超高速撞击实验研究.弹丸直径为3.97 mm,撞击速度分别为(2.58±0.08)km/s、(3.54±0.25)km/s和(4.35±0.11)km/s,板间距为10~100 mm.实验得到了铝双层板结构在不同撞击速度区间的后板损伤模式.结果表明,弹丸撞击速度一定时,后板弹坑分布随前后板间距的不同而不同.前板背面返溅影响区和后板弹坑分布区随板间距的增大而增大,各弹坑分布区扩散角随板间距的增大而减小. 相似文献
898.
自动造型生产线附线运动平稳性研究 总被引:1,自引:0,他引:1
机械化和自动化是铸造生产的重要课题,而作为机械系统的组成部分,附线的输送系统的运动功能和运动平稳性对生产过程影响较大.基于Solidworks软件建立了附线各部件的参数化三维几何模型,根据Hertz接触模型和恢复系数模型建立了附线系统的接触动力学模型.在ADAMS环境中,将液压系统简化为直线驱动单元和阻尼器,并根据系统的拓扑结构建立了附线的多体系统动力学模型.提出了临界阻尼系数和参数匹配的策略,并进行动力学仿真计算.仿真结果表明合理的阻尼系数能够保证台车运动平稳、冲击减小、并提高运动过程中和最终定位的位置精度.这对于提高生产效率和铸件质量具有重要意义.该方法与结果已应用于实际附线系统的运动功能调试. 相似文献
899.
900.
峰前围压卸荷条件下岩石的应力-应变全过程分析和变形局部化研究 总被引:10,自引:2,他引:10
地下工程和边坡工程开挖一般处于卸荷条件。岩石在加载和卸荷条件下的力学特性不同,研究岩石在卸荷条件下的强度特性具有重要的理论和现实意义。根据损伤断裂力学知识建立了岩石处于卸荷条件下的全过程应力-应变关系,包括线弹性阶段、非线性强化阶段、应力跌落和应变软化阶段。理论和试验研究发现,岩石卸荷破坏所需要的应力比连续加载破坏时小,且卸荷破坏时的变形比连续加载时大,其主要原因是卸荷时存在裂纹张开,裂纹张开导致了无摩擦滑动和变形模量的减少,岩石的无摩擦滑动必定比摩擦滑动所需的应力小。通过和试验结果的比较验证了该理论的有效性和正确性,该理论对边坡工程和地下工程开挖具有重要的参考价值。 相似文献