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61.
分析了电气设备绝缘电阻,温度和容量对吸收比的影响,指出吸收比作为绝缘预防性试验判据有一定的局限性,提出了克服吸收比局限性的对策。  相似文献   
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BACKGROUND: The results of palliative chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil (CMF) in patients with advanced breast cancer who received adjuvant therapy with the same regimen were investigated. RESULTS: Of 47 patients, 14 (30%) achieved an objective remission (median duration 9.5, range 5-21 months) and 8 (17%) stabilisation of disease (median duration 6, range 3-17 months). Objective remissions were observed in premenopausal as well as in postmenopausal women, in patients with all categories of dominant localisation of disease and regardless of the oestradiol receptor status of the primary tumour or eventual previous endocrine therapy. One of 4 and 13 of 43 patients who started palliative chemotherapy within or later than 12 months after the last adjuvant course obtained an objective remission. The median survival time from start of therapy of all treated patients was 12 (range 1-40) months. Patients with an objective remission or stable disease and patients with progressive disease had a median survival time of 20 (range 6-40) and 6 (range 1-35) months respectively (p < 0.0001). CONCLUSIONS: Palliative treatment with CMF should not be rejected for patients who have relapsed after adjuvant chemotherapy with the same modality.  相似文献   
64.
A favourable effect of sanatorium treatment on the key body functions was found in children with thyroid hyperplasia consequent to environmental pollution due to Chernobyl accident. It is emphasized that balneofactors in the above children should be used in sparing regimens.  相似文献   
65.
The syndrome of hypoparathyroidism associated with growth retardation, developmental delay, and dysmorphism (HRD) is a newly described, autosomal recessive, congenital disorder with severe, often fatal consequences. Since the syndrome is very rare, with all parents of affected individuals being consanguineous, it is presumed to be caused by homozygous inheritance of a single recessive mutation from a common ancestor. To localize the HRD gene, we performed a genomewide screen using DNA pooling and homozygosity mapping for apparently unlinked kindreds. Analysis of a panel of 359 highly polymorphic markers revealed linkage to D1S235. The maximum LOD score obtained was 4.11 at a recombination fraction of 0. Analysis of three additional markers-GGAA6F06, D1S2678, and D1S179-in a 2-cM interval around D1S235 resulted in LOD scores >3. Analysis of additional chromosome 1 markers revealed evidence of genetic linkage disequilibrium and place the HRD locus within an approximately 1-cM interval defined by D1S1540 and D1S2678 on chromosome 1q42-43.  相似文献   
66.
In 12 subjects, a pliable, yet unbreakable, intercuspal interference (aluminum shim onlay splint; uniform height of 0.25 mm) was placed between either the right or left maxillary and mandibular second premolars and first molars. During brief and forceful biting (dynamic chewing stroke of about 20 kg force) the interference emulated a semisoft food bolus, and at the end of biting (subsequent static clenching stroke of about 20 kg force) it emulated a rigid metal interference. During dynamic/static biting, rotational electrognathography measured maximum frontal and horizontal plane torque of the right and left mandibular condyles. Eleven subjects (92%) showed frontal plane upward rotation (mean of 1.0 degree) of the condyle contralateral to the interference, and one subject (8%) showed frontal plane upward rotation (0.4 degree) of the condyle ipsilateral to the interference. Two subjects (17%) showed no horizontal plane rotation; seven subjects (58%) showed backward rotation (mean of 0.4 degree) of the condyle contralateral to the interference; and three subjects (25%) showed backward rotation (mean of 0.3 degree) of the condyle ipsilateral to the interference. It is suggested that, in the presence of an occlusal interference, mastication may have both short- and long-term detrimental effects.  相似文献   
67.
故障预测作为基于状态维修实现的关键,可以有效支持维修管理者的决策。参照国际标准化组织对故障预测的定义,划分故障预测过程,提出预测方法性能评估至少存在的两种方式,在分类和比较现有预测方法的基础上,明确预测方法的适用范围和限制条件,为工程预测系统的构建提供参考。  相似文献   
68.
Alpha稳定分布随机变量的产生   总被引:1,自引:0,他引:1  
在实际应用中遇到的大量的非高斯信号或噪声具有显著的尖峰脉冲特性,其概率密度函数的衰减过程比高斯分布要慢,表现出显著的拖尾。而基于广义中心极限定理的Alpha稳定分布描述了信号统计分布的非高斯性和重拖尾性。实现服从Alpha稳定分布随机变量的仿真是开展相关研究的基础。该文由S2参数系下的分布模型的仿真算法导出标准参数系下Alpha稳定分布随机变量的仿真算法。并通过仿真实验证实了该仿真算法的可行性。  相似文献   
69.
由于目前的电子引伸计精度不高、不快捷、智能化程度不高,对其数字智能化方向的研究十分必要。从数字智能式电子引伸计的特点、关键技术、技术指标及应用入手,制定开发的技术路线,并介绍相应的信号处理技术。  相似文献   
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