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81.
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   
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83.
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   
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85.
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   
86.
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   
87.
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   
88.
TUVP手术时间对血红蛋白及电解质的影响   总被引:2,自引:0,他引:2  
目的 了解经尿道前列腺汽化电切手术时间对血红蛋白及血清电解质的影响。方法 对64例经尿道前列腺汽化电切术患按手术时间分组,观察手术前后血红蛋白及血清电解质的变化。结果 手术时间对血清电解质的降低有的影响,对血红蛋白降低的影响不显。结论 减少TUR综合征的关键是要操作熟练,缩短手术时间及手术中注意止血。  相似文献   
89.
武翠凤  李敏 《中国全科医学》2004,7(19):1382-1384
目的 观察穴位注射丹参合并小剂量抗精神病药物与单用抗精神病药物治疗精神分裂症的疗效。方法16 0例患者随机分为治疗组 10 0例 ,对照组 6 0例 ;辨证分为 5型 ,用阴阳经相配取穴的方法 ,根据疾病的虚实 ,用迎随和徐疾补泻手法 ,治疗组每日注射 1次 ,10次为 1疗程 ,共治疗 3个疗程 ;用简明精神症状量表 (BPRS)和药物副反应量表 (TESS)评定疗效和副反应 ,治疗结束后随访两年。结果 治疗组痊愈率、显效率与对照组间差异有显著性意义 (P <0 0 5 )。BPRS和TESS量表于每疗程结束后两组评分比较差异均有显著性意义 (P <0 0 5 ) ;复发率与对照组间差异有显著性意义 (P <0 0 5 )。结论 穴位注射丹参具有见效快、副作用少、远期疗效好的特点。实施有效的护理 ,适时的健康教育是提高患者依从性 ,保证有效治疗、取得良好效果的重要手段。  相似文献   
90.
A method has been derived for calculating the mean absorption time of an oral drug and its interconversion metabolite which is generated from the drug systemically and presystemically. The method evolves from the convolution integral and requires plasma AUC and AUMC values after separate intravenous administration of the drug and its interconversion metabolite and oral administration of the drug. It can also be used to calculate the mean input time of a drug undergoing reversible metabolism and administered by any other extravascular route. Results of a simulation study using both errorless and errant data indicate that, when the absorption rate constant of a drug or its interconversion metabolite is not much larger than the apparent elimination rate constant, the proposed method performs satisfactorily. However, when the absorption rate constant of a drug or its interconversion metabolite is much larger than the apparent elimination rate constant, the proposed method appears to be inaccurate.  相似文献   
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