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11.
目的 进一步证实 P P D 实验在监测结核免疫力中的应用价值。方法 用卡介苗接种879名儿童,12 周后进行 P P D 试验并查验卡痕反应,计算评价筛选试验的指标。结果 卡痕试验的敏感度、特异度、正确指数均低,而误诊率、漏诊率均高。结论  P P D 实验是目前尚未开展人体内测定结核免疫力前唯一有效的监测结核免疫力的方法。  相似文献   
12.
用免疫酶法分析了糖尿病患者及甲状腺疾病患者血清中胰岛细胞抗体(ICA)的水平。结果为经胰岛素吸收后,IDDM组阳性率为46.7%(最高),NIDDM组阳性率为13.3%,甲状腺疾病组(其中1例Graves’病伴糖尿病ICA阳性)阳性率为4%,健康组0。统计学分析,P〈0.05,具有显著性差异,表明ICA是Ⅰ型糖尿病的特异性免疫标志物,ICA检测作为对IDDM与NIDDM的鉴别诊断,特别是对LADA  相似文献   
13.
论阿是穴与穴位特异性   总被引:9,自引:1,他引:9  
喻晓春  高俊虹  付卫星 《针刺研究》2005,30(3):183-186,190
中医理论认为,阿是穴是体表具有按之快然或疼痛等特点的位点。从理论上来说,阿是穴包含有具有特异性的经穴和其它常用穴;从功能上来讲,阿是穴实际上与现代医学的牵涉痛的体表部位类似。因此,阿是穴乃是在反映病邪和治疗疾病等两大穴位功能方面具有明显特异性的穴位,本文就此进行了论述。  相似文献   
14.
ROC analysis of alcoholism markers – 100% specificity   总被引:1,自引:0,他引:1  
A combination of 4 so-called markers of alcoholism, i. e. methanol, aceton + 2-propanol, γ-glutamyl-transferase and carbohydrate deficient transferrin, was investigated in 341 blood samples from alcoholics and non-alcoholics. From the history of alcohol consumption, four defined subgroups were formed: non-alcoholics divided into (A) 33 persons with no ethanol consumption during the past year and (B) 60 persons with daily consumption less then 40 g ethanol. Alcoholics were divided into (C) 177 persons with no ethanol at the time of admission/first blood sampling (withdrawal therapy) and (D) 71 persons with positive ethanol levels on admission/first blood sampling. All markers showed different extents of overlap between the collectives of alcoholics and non-alcoholics. By logistic regression, a formula was developed combining these markers with different mathematical weights. Thus an “Alc-Index” could be calculated for each individual. The ROC curve connecting all individual values gives an ideal form with 100% specificity and nearly 93% sensitivity. The threshold between the collectives of alcoholics and non-alcoholics was defined by the Alc-Index value 1.7. This was associated with no false positives among the non-alcoholics while nearly 93% of the alcoholics exceeded this index. The ROC-based calculation of the Alc-Index thus seems to be the most effective method for the diagnosis of alcoholism. Received: 24 June 1999 / Received in revised form: 1 November 1999  相似文献   
15.
The purpose of this study was to determine the sensitivity, specificity, positive and negative predictive values for Corah's Dental Anxiety Scale (DAS) and two modified versions of it (MDAS; MDAS/4). A questionnaire was mailed to a simple random sample of 1,190 25-year-old residents in the west of Norway in 1997. Half the sample received DAS, the other half MDAS. The response rate after one reminder was 62%. The respondents completed the scales, gave demographic particulars and answered one question about dental visiting habits during the last 5 years plus an open-ended question about reasons for nonattendance. Using the answers to the latter question as validating criterion, it was found that, for all scales, sensitivity decreased while specificity improved when changing from a liberal to a stringent cut-off point. The scales gave low positive predictive values (≤0.26), but high negative predictive values (≥0.98). Since DAS and MDAS/4 gave almost identical findings, the two samples were combined. At a cut-off point ≥13 sensitivity was 0.83, specificity 0.84, positive predictive value 0.18 and negative predictive value 0.99. The corresponding estimates when the cut-off point was ≥15 were 0.67, 0.90, 0.22 and 0.98. It is concluded that, in this test, DAS and the two versions of MDAS gave acceptable, or near acceptable sensitivity, specificity and negative predictive values, but far too low positive predictive values to be useful for prediction at the individual level.  相似文献   
16.
17.
《Injury》2016,47(12):2769-2771
Non-displaced hip fractures can be difficult to diagnose on plain film radiographs. When there is ongoing clinical suspicion of an occult fracture, further imaging is obtained. We investigated the sensitivity of computed tomography (CT) scans in detecting these fractures and the delays to surgery that three-dimensional imaging causes. We identified 78 CT scans performed for possible hip fractures over the past 3 years with the presence and absence of a fracture recorded. Based on subsequent imaging, the accuracy of CT scans was determined. CT scanning yielded sensitivity was 86% and specificity 98% for occult hip fracture (OHF). The median delay to definitive diagnosis was 37 h. Our results demonstrate that CT scan does not bear sufficient sensitivity to detect all OHFs. We therefore recommend that MRI should be offered when a fracture is suspected. CT scans should be reserved for when MRI is not available, but a negative scan should be confirmed with subsequent MRI.  相似文献   
18.
目的:探讨产时胎心监护减速区面积在新生儿酸中毒预测中的价值。方法:分析2011年2月至2013年10月在北京大学第三医院住院分娩足月单胎孕产妇204例的分娩前30分钟的胎心监护图形的减速区面积,根据p H7.20和(或)碱剩余-12.00 mmol/L分为酸中毒组(26例)和对照组(178例),探讨胎心监护图形的减速区面积与新生儿脐动脉血气的关系,并绘制受试者工作特性曲线(ROC曲线),计算曲线下面积(AUC),预测酸中毒的敏感性和特异性。结果:酸中毒组减速区面积(18.00 cm~2)明显大于对照组(10.50 cm~2),差异有统计学意义(P0.05)。分娩前30分钟图形的减速区面积的AUC为0.663(95%CI 0.541~0.785),预测酸中毒的敏感性为61.5%,特异性为72.5%。结论:产时胎心监护减速区面积对预测新生儿酸中毒有一定价值,特异性较高,而敏感性欠佳,建议结合更多图形指标解读图形对新生儿酸中毒的预测。  相似文献   
19.
The pandemic influenza A/H1N1 outbreak resulted in 18,449 deaths in over 214 countries. In Taiwan, the influenza rapid test, an in vitro diagnostic device (Flu-IVD), only requires documented reviews for market approval by the Taiwan Food and Drug Administration. The purpose of this study was to investigate the analytical sensitivity and specificity of Flu-IVDs used in Taiwan. Analytical sensitivity and specificity tests were performed for influenza antigens A/California/7/2009 (H1N1) virus, A/Victoria/210/2009 (H3N2) virus, B/Brisbane/60/08 virus, and human coronavirus OC43. A total of seven domestic and 31 imported Flu-IVD samples were collected, of which, 20 samples had inadequate labeling, including those with removed package inserts or incorrect insert information. The analytical sensitivity of Flu-IVDs for A/H1N1, A/H3N2, and Flu B was 500–1000 ng/mL, 1000 ng/mL, and 1000 ng/mL, respectively. For the 50% cell culture infective dose (CCID50) label, the average A/H1N1 and A/H3N2 sensitivity for Flu-IVDs was log10 5.8 ± 0.5 and log10 6.6 ± 0.5 CCID50/mL, respectively. As to the specificity test, no product cross-reacted with human coronavirus OC43. This study provides important information on the Flu-IVD regulation status and can thus help the government formulate policies for the regulation of in vitro diagnostic devices in Taiwan.  相似文献   
20.
The performance of enzyme linked immunosorbent assays (EAST) for identifying six indoor allergens was evaluated using skin prick test (SPT) as reference tests in 154 children with allergic rhinitis. Sensitivity of EAST ranged from 9% (cat) to 54% (HDM) with specificity of 74%(cockroach) to 100% (cat) with an agreement ranged from 58 to 86%. Cut off values ?> ?0.35 kU/L showed best sensitivity and specificity. Our findings agree with extant literature which suggests that the ability of EAST to determine the precipitating allergen is moderate. Assays for definitively identifying the inhalant allergen are currently not available.  相似文献   
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