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11.
CI Henschke DF Yankelevitz A Wand SD Davis M Shiau 《Canadian Metallurgical Quarterly》1996,34(1):21-31
264 patients with cancer of larynx, 21 female and 234 male, had a testosterone and sex hormone binding globulin (SHBG) before the treatment in serum estimated. Because of dependence of levels of hormones the group of patients was divided into three following groups: "lower than standard", "standard", "higher than standard". The correlation between these groups and sex, age, localization of tumor, organs' advances, stage of morphological malignancy and type of cancer was reported. Anomalous values of testosterone were in male group more frequently reported. Anomalous values of SHBG were similar in male and female groups, but in the female group there was a significant majority of "lower than standard" values reported. The majority of abnormal values of testosterone and SHBG was described in groups of age higher than 50 years. There were no differences in testosterone and SHBG levels in different localization of tumors in larynx. In advanced stage T3 and T4 there were more frequent lower mean values of testosterone levels and higher values of SHBG levels in comparison to T2 stages. In tumors in G1 and G2 stages of histological malignancy higher levels of SHBG and higher mean levels of testosterone. The tumors in stage G3 the hormone levels were lowers were observed. The levels of SHBG in groups of carcinoma planoepitheliale keratodes were in 66% higher than in a group of carcinoma planoepitheliale akeratodes but in both groups the levels of testosterone were nearing the same. In group of patients with larynx cancer the negative correlation between the levels of testosterone and SHBG was not observed. Higher SHBG levels were not always accompanied by lower testosterone levels. 相似文献
12.
板翅式全热交换器运行条件对性能影响的研究 总被引:4,自引:1,他引:4
对板翅式全热交换器在不同运行条件下的性能进行了实验研究,分析了性能参数和运行参数之间的关系,指出了风量与阻力损失、空气温湿度差与换热效率的关系. 相似文献
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BREW是一种嵌入式开发应用平台,提供一个高效、低成本、可扩展的应用程序执行环境(AEE),在BREW平台上开发的应用程序可无缝植入任何移动设备。为使移动设备有效地支持地理信息系统的服务,提出了基于固定主机——移动设备的两级结构。通过对一款自行设计的运行于BREW平台上的系统的介绍,说明如何解决移动设备硬件的低配置与地理信息系统对硬件高需求之间的矛盾,并详细介绍了为解决这一矛盾而提出的分块技术与索引技术的思想。 相似文献
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甲玛矿床位于西藏冈底斯成矿带,其勘查和研究程度均较高,矿体由斑岩型矿体、矽卡岩型矿体、角岩型矿体及外围独立金矿体组成,具有多元矿体结构,其成矿元素为Cu、Mo、Pb、Zn、Au和Ag,呈现多金属成矿作用特征。矿区深部及外围的勘查找矿方向一直是地质学者们关注的热点。在斑岩成矿系统理论的指导下,近年来在甲玛矿区深部及外围取得了重大找矿突破。基于最新勘查成果,甲玛矿床共探获铜资源储量超过850×104 t,钼资源量达91×104 t,铅锌资源量超过150×104 t,伴生金储量为220 t,伴生银储量超过1×104 t,达到超大型矿床规模。为进一步指导区域及外围勘查找矿工作,以甲玛矿区最新勘查成果为基础,通过对矿区钻孔的详细编录,采用地表构造蚀变填图等方法,系统解剖了甲玛矿区不同矿段的矿体地质结构,并揭示了其矿床地质特征。结合甲玛矿区新发现的主矿段深部的厚大矽卡岩矿体和外围则古朗北矿段的巨厚斑岩型矿体,分析了矿区深部及外围找矿潜力,认为甲玛矿区深部仍存在厚大矽卡岩铜钼矿体和斑岩钼矿体,应进一步加强对外围则古朗北矿段新发现的斑岩矿体、矽卡岩矿体和角岩型矿体的勘查,建立新的资源储备。此外,归纳总结有效勘查找矿方法,以期为深入探究甲玛矿床成矿作用和创建综合勘查找矿模型提供参考依据,并通过系统梳理矿区已有勘查和研究资料,总结甲玛矿床的找矿标志,为区域类似矿床的地质勘查提供重要线索,也为青藏高原斑岩成矿系统的勘查和研究工作奠定坚实基础。 相似文献
17.
DF Yankelevitz D Shaham A Shah J Rademacker CI Henschke 《Canadian Metallurgical Quarterly》1998,22(6):398-403
OBJECTIVE: The aim of this study was to evaluate the feasibility and reproducibility of a novel image-scoring method of first-trimester nuchal translucency measurement as an objective tool of ongoing audit and training. DESIGN: This was an independent evaluation of nuchal translucency images by three separate reviewers unaware of the examiner. SUBJECTS: There were 105 consecutive singleton pregnancies undergoing first-trimester screening. METHODS: Each image was scored according to the following criteria: section (oblique, 0; mid-sagittal, 2), caliper placing (misplaced, 0; proper, 2), skin line (nuchal only, 0; nuchal and back, 2), image size (unsatisfactory, 0; satisfactory, 1), amnion (not visualized, 0; visualized, 1) and head position (flexion/hyperextension, 0; straight, 1). The final score was categorized into one of four quality groups: excellent (8-9), reasonable (4-7), intermediate (2-3), unacceptable (0-1). RESULTS: The distributions of the four quality groups were similar between the three reviewers: 11.4% were classified as excellent, 57.1% as reasonable, 25.7% as intermediate and 5.7% as unacceptable. Inter-reviewer agreement showed identical classification, by each pair of reviewers, from 65.7% to 74.3%, and partial agreement to neighboring quality groups from 25.7% to 34.3% of the cases. In none of the cases did the reviewers differ in categorizing cases to remarkably different quality groups. Application of the auditing method to the examiners showed similar distribution to the various quality groups and similar mean final score of 4.69 (0.39, SE), 4.54 (0.15, SE) and 4.65 (0.15, SE). CONCLUSIONS: The described image-scoring method represents a new approach towards the evaluation of ultrasound performance as a whole and nuchal translucency measurement in particular. It may be employed by every center in an independent manner with minimal resources and regardless of the method of risk assessment. More studies will be needed to determine the standards required from the examiners and to elucidate the contribution of the proposed auditing method to the examination's quality and the process of training. 相似文献
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Ragan CI 《Metal-Based Drugs》1997,4(3):125-132
Metal ions are believed to participate in many neurodegenerative conditions. In excitotoxic cell death there is convincing evidence for the participation of Ca(2+) and Zn(2+) ions although the exact molecular mechanisms by which these metals exert their effects are unclear. Only in one instance has the metal binding site of metalloenzymes been exploited for therapeutic purposes and this is the use of Li(+) in the treatment of bipolar affective disorder. Again the exact molecular target is not clear but is likely to involve a Mg(2+)-dependent enzyme of an intracellular signalling pathway. In Parkinson's disease, the selective loss of dopaminergic neurones in the substantia nigra may be caused by radical-mediated damage and there is good evidence to suggest that Fe(2+) or (3+) is important in promoting formation of radical species. The evidence that free radicals are important in mediating other neurodegenerative conditions is less strong but still substantial enough to suggest that removal of reactive oxygen species or preventing their formation may be a valid approach to therapy. 相似文献