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71.
Non-invasive tear break-up time (NITBUT) has been proposed as a measure of tear film integrity which is superior to the more commonly used tear break-up time (TBUT), since it does not alter the volume or the physicochemical properties of the tear layer by the addition of fluorescein. We measured NITBUT by measuring the time taken for distortions or discontinuities to appear in the reflected image of a grid pattern which covered about 80 per cent of the corneal surface. NITBUT measures were made 100 times on seven Hong Kong Chinese subjects with up to 20 consecutive measures being made on a single day. We also measured NITBUT on one occasion on an unselected population of 52 Hong Kong Chinese subjects. NITBUT shows a skewed distribution in all subjects, with many shorter values and some extremely long values. There are statistically significant variations in NITBUT from day to day, and from subject to subject. The group of 52 subjects also had a skewed NITBUT distribution with many short values and some very long values. The arithmetic mean does not adequately represent NITBUT data, either for individual subjects or for this group of subjects. As many as five to eight measures may be necessary to gain a stable estimate of the NITBUT and stability of the measure is improved if extreme values are omitted. We recommend the use of nonparametric statistics to compare NITBUT values from day to day in or between subjects. 相似文献
72.
73.
A. BACCARELLI† A. ZANOBETTI I. MARTINELLI‡ P. GRILLO† L. HOU§ S. GIACOMINI† M. BONZINI† G. LANZANI¶ P. M. MANNUCCI‡ P. A. BERTAZZI† J. SCHWARTZ 《Journal of thrombosis and haemostasis》2007,5(2):252-260
BACKGROUND: Consistent evidence has indicated that air pollution increases the risk of cardiovascular diseases. The underlying mechanisms linking air pollutants to increased cardiovascular risk are unclear. OBJECTIVES: We investigated the association between the pollution levels and changes in such global coagulation tests as the prothrombin time (PT) and the activated partial thromboplastin time (APTT) in 1218 normal subjects from the Lombardia Region, Italy. Plasma fibrinogen and naturally occurring anticoagulant proteins were also evaluated. METHODS: Hourly concentrations of particulate (PM10) and gaseous pollutants (CO, NO2, SO2, and O3) were obtained from 53 monitoring sites covering the study area. Generalized additive models were applied to compute standardized regression coefficients controlled for age, gender, body mass index, smoking, alcohol, hormone use, temperature, day of the year, and long-term trends. RESULTS: The PT became shorter with higher ambient air concentrations at the time of the study of PM10 (coefficient = -0.06; P < 0.05), CO (coefficient = -0.11; P < 0.001) and NO2 (coefficient =-0.06; P < 0.05). In the 30 days before blood sampling, the PT was also negatively associated with the average PM(10) (coefficient = -0.08; P < 0.05) and NO2 (coefficient = -0.08; P < 0.05). No association was found between the APTT and air pollutant levels. In addition, no consistent relations with air pollution were found for fibrinogen, antithrombin, protein C and protein S. CONCLUSIONS: This investigation shows that air pollution is associated with changes in the global coagulation function, suggesting a tendency towards hypercoagulability after short-term exposure to air pollution. Whether these changes contribute to trigger cardiovascular events remains to be established. 相似文献
74.
75.
非霍奇金淋巴瘤85例临床及预后分析 总被引:3,自引:0,他引:3
目的:分析多种因素对非霍奇金淋巴瘤(NHL)预后的影响。方法:通过SABC法进行免疫分型,采用Kaplan—Meier法分析患者治疗后的生存期,采用Cox比例风险模型分析影响预后的因素。结果:B细胞来源-NHL(B-NHL)发病率为63.3%。T细胞来源-NHL(T—NHL)为36.7%;低度恶性占17.6%,中、高度恶性占74.1%。1、2、3、5年生存率:低度恶性患者为92.1%、84.5%、65.1%、45.1%;中、高度恶性患者为84.9%、67.5%、47.6%、28.4%。I、Ⅱ期患者为98.8%、91.5%、87.5%、70.3%;Ⅲ期、Ⅳ期患者为62.1%、55.5%、40.1%、23.8%。T—NHL为70.8%、53.5%、47.7%、30.2%;B-NHL为82.1%、70.5%、61.1%、50.1%。结论:年龄、乳酸脱氢酶水平、恶性程度、临床分期、免疫分型、身体状况评分(PS)是影响NHL预后的重要因素。 相似文献
76.
一次阿扑吗啡注射对大鼠视觉辨别学习和工作记忆的影响 总被引:3,自引:1,他引:2
目的探讨多巴胺受体激动剂 -阿扑吗啡对大鼠视觉辨别学习和工作记忆的影响。方法利用旋转T迷宫装置 ,通过食物强化 ,分别训练大鼠正常和逆反的视觉辨别学习任务。动物达到规定的标准次数后 ,腹腔注射 2mg/kg体重的阿扑吗啡 ,3 0分钟后观察药物对工作记忆的影响。 结果对于正常学习 ,阿扑吗啡注射组动物的正确次数与生理盐水对照组相比无显著性差异 ,且两组动物继续进行逆反学习训练 ,达到学习标准所需的总次数亦无显著性差异 ;对于逆反学习 ,阿扑吗啡注射组动物的正确次数较对照组显著降低。结论单独一次阿扑吗啡注射可能干扰大鼠逆反学习的工作记忆 ,但不影响正常学习的工作记忆和逆反学习的过程。 相似文献
77.
Among British-qualified doctors of 1974 and 1977, about 80% held postgraduate qualifications of some kind. The commonest qualifications were DRCOG, MRCP and MRCOG. There were considerable differences between medical schools in the numbers of qualifiers taking various examinations. Apart from the MRC Psych, DRCOG and Family Planning Certificate, qualifications were more commonly held by men than women. Tables show the type of work being done 9-13 years after leaving medical school by holders of various postgraduate qualifications; e.g. 60% of MRCP holders were working in medicine or a medical specialty and 84% of FRCS holders in general surgery or a surgical specialty. Discussion deals with the plurality, specificity, variability, perceived necessity, sufficiency, international utility and career significance of British postgraduate qualifications. 相似文献
78.
目的:探讨数学障碍儿童的工作记忆状况。方法:采用智力测睑、成就测验、教师提名、学业成绩相结合的综合标准甑选数学障碍儿童,在长沙市三所小学随机选取4~6年级共12个班,从中抽取24名数学障碍儿童和24名学习正常儿童。采用工作记忆成套测验对2组被试进行评估。结果:数学障碍组除空间排序、空间后退以及数字划销3个分测验外,在工作记忆成套测验其它各分测验及各维度上的成绩均显著低于学习正常组(P〈0.001~0.05)。结论:数学障碍儿童工作记忆存在普遍缺陷。 相似文献
79.
目的:评价自制不透X线标志物的临床应用价值,并确定正常人胃排空及胃肠道通过时间的正常值。方法:采用X线法对60例健康志愿者餐后1 h、2 h3、h的胃排空及24 h4、8 h肠道标志物排出情况进行观察。结果:正常人标准餐后3 h胃排空率为41.1±30.0%,24 h和48 h肠道标志物排出率分别为73.5±29.8%、99.0±20.9%。结论:自制的标志物具有良好的屏蔽功能;X线法胃排空及胃肠通过时间测定方法简单实用,值得临床推广。 相似文献
80.
额叶外伤后早期数字工作记忆的fMRI研究 总被引:5,自引:1,他引:4
目的:利用功能磁共振成像技术研究额叶外伤后,执行工作记忆任务时脑结构损伤与脑激活功能区的改变。材料和方法:对10例额叶外伤后早期患者(伤后平均31d,其中男性7例,女性3例;平均年龄30.1年)和12例正常志愿者作为对照组(男性7例,女性5例;平均年龄26.9年)分别进行2位和4位数字的正反序工作记忆的实验,使用single-trial设计方法;GE3.0T磁共振机扫描、采集图像,运用AFNI软件包进行数据分析。结果:①正常对照组反序4位数字任务大于正序4位数字脑区有辅助运动区SMA,双侧背外侧前额叶,左侧顶叶,右侧角回;②患者组反序4位数字任务大于正序4位数字的脑区有左侧枕叶;③正常对照组反序4位数字任务大于患者组的部位有左侧DLPFC,左侧角回;正序4位数字大于患者组的部位有左侧枕叶,右侧角回;④患者组反序4位数字任务时大于对照组的部位有楔状回,右侧Broca区;正序4位数字大于对照组的部位有右侧初级运动区MA,右侧额极区。结论:前额叶在脑工作记忆网络中处于重要节点,大脑右侧半球在工作记忆系统中起到巨大代偿作用的脑资源,fMRI提供认知功能损伤的影像学依据,应在临床上发挥更大作用。 相似文献