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1.
Waseem Raza Hafiza Anum Mohy-u-Din Sajid Shaeen Malik Iqra Manzoor Baby Nadeem 《Ultrasound in medicine & biology》2019,45(1):21-25
The objective of the study was to evaluate the reliability of sonoelastography in ductal carcinoma in patients in primary and secondary health care settings. Google Scholar, PubMed, Medline, Medscape, Wikipedia and NCBI were searched in January 2018 for all original research and review articles to identify relevant studies. Two reviewers selected the articles independently for based on the title and abstract. The selection criteria were sonoelastography accuracy for diagnosing ductal carcinoma as index text, B-mode sonography, and micropure imaging; surgery and histologic findings were used as reference text; and benign and malignant breast abnormalities and ductal carcinoma were used as target conditions. Two reviewers extracted the data on selected study characteristics, and the results were used to construct the tables and figures. Fifteen studies on ductal carcinoma were found. The overall sensitivity of sonoelastography in diagnosing ductal carcinoma was 85.7%, and the specificity, 79.8%. On the basis of the literature review, it was concluded that sonoelastography has high sensitivity and specificity in diagnosing ductal carcinoma. 相似文献
2.
Probabilistic genotyping approaches are increasingly used for the interpretation of DNA mixtures. To explore the specificity of one of these systems (STRmix™), we conducted an extensive study using 24 complex mixtures: all were known or apparent 4-person mixtures with at least one contributor representing less than 20% of total DNA, and all mixtures had at least one contributor with suboptimal DNA quantity. Those mixtures were either generated in-house or from casework. All the mixtures were compared to 300,000 virtual non-contributors, resulting in a dataset of 7.2 million comparisons. The great majority of the non-contributor comparisons led to a LR lower than 1 for a specificity of 99.1%. The effect of using replicate amplifications to calculate the LR of non-contributors was also assessed as triplicates were used and led to an increased specificity of 99.8%. The very large extent of the analyzed data shows that STRmix™ has an excellent ability to discriminate non-contributors from complex DNA mixtures. 相似文献
3.
In the study of monozygotic twins relative to disease and risk factors, particular interest focuses on the subset who are discordant for some suspected risk factor (for example, smoking), since such twins constitute a natural case-control pair. In such studies, questionnaires designed to identify the status of all twin pairs are sometimes error prone and can yield misleading estimates of the concordance-discordance ratios. Greater efforts to verify the characteristics of apparently discordant pairs than to verify those of apparently concordant pairs can result in the 'unequal ascertainment' fallacy. Using the results of a questionnaire with known error rates and the 'apparent' frequencies yielded, we present unbiased, maximum likelihood estimates of the 'true' proportions of concordant and discordant pairs. concordant and discordant pairs. We also present approximate covariances among these estimates. 相似文献
4.
近年来,随着类风湿性关节炎发病机制及某些致炎因子的发现,出现了一系列新药。环氧合酶-Ⅱ特异性抑制剂与传统的非甾体类抗炎药相比具有疗效好、副作用小的优点;早期联合使用改变病情性抗风湿药在近期内有较好的临床疗效。此外重组可溶性肿瘤坏死因子受体融合蛋白 (etanercept)、人体抗肿瘤坏死因子-α单克隆抗体(adalimumab)和阿那白滞素(anakinra)等生物学治疗及中药治疗均显示了新的治疗前景。 相似文献
5.
Psychophysiology is just as closely related to internal medicine as it is to psychiatry. “Psychological variable” has two distinct meanings: a) an external sensory stimulus, or b) an organismic state described in psychological language. “Psychological” and “Physical” are names of two different languages. There is no such thing as a non-physical illness. Asking whether emotions cause diseases, or diseases cause emotions, leads to many difficulties and is unprofitable. It is far more useful to ask about stimulus-response relationships. There are more kinds of specificity relations in psychophysiology and psychosomatic medicine than are usually recognized, and the usual specificity statements in psychosomatic medicine are not concerned with I-R or S-R specificity. There are many problems in medicine which psychophysiology could help to solve. 相似文献
6.
A protamine sulphate (PS) pretreated solid phase coated with different amounts of dsDNA has been used to develop a sensitive, specific and reproducible anti-dsDNA ELISA. Using low concentrations of a dsDNA coat 50% of SLE sera were found to be positive and false positive reactivity due to anti-PS reactivity was found in 3/40 patients with other auto-immune diseases (OAID). In contrast, when PS was saturated with higher concentrations of dsDNA 80% of SLE sera were detected, the reproducibility of the results was better and anti-PS reactivity of OAID patients with an anti-PS reactivity disappeared. The sera of three other OAID patients contained low avidity anti-dsDNA, measured after a salt elution step in the ELISA procedure, and 2/60 patients with non-auto-immune disease exhibited a false positive anti-dsDNA reactivity since they reacted with the solid phase even in the absence of PS and dsDNA. Thus an ELISA procedure using a PS pretreated solid phase permits the sensitive, specific and reproducible measurement of anti-dsDNA antibodies only if a high concentration of dsDNA is coated on the PS and appropriate controls are performed. 相似文献
7.
吗啡和甲基安非他明单克隆抗体联合胶体金检测试卡的研制 总被引:1,自引:0,他引:1
目的:研制吗啡-甲基安非他明单克隆一步法毒品二合一胶体金检测试卡,用于毒品的检测和可疑人群的筛查。方法:应用杂交瘤技术制备抗吗啡-甲基安非他明的单克隆抗体(McAb);ELISA方法检测McAb效价;免疫胶体金技术制备二合一胶体金检测试卡。结果:①ELISA法检测McAb的效价:抗吗啡McAb的效价为1∶3.2×103,抗甲基安非他明McAb的效价为1∶1.6×103。②检测试卡的灵敏度:检测尿中吗啡的最低浓度为300ng/ml,甲基安非他明的最低浓度为1000ng/ml;③检测试卡的特异性:7天以上未吸毒者饮用可口可乐、口服感冒药及吸烟等其尿中未检出阳性反应。④与Pan Probe Biotech公司的单一检测吗啡和甲基安非他明试纸灵敏度对比实验显示出吸毒后4~5天的尿样仍呈阳性反应。结论:由于具有高度敏感性和特异性,以及快速、直观等优势,本试卡在毒品滥用筛查工作中有重要的定性判别意义。 相似文献
8.
两种新的HCC抗原的特异性 总被引:1,自引:1,他引:0
目的:检测两种新的人肝细胞癌(HCC)抗原(编号为HCC-1-8a和HCC-3-13)对HCC的特异性。方法:应用重组克隆表达抗原的血清学技术(SEREX),用异体HCC血清和非HCC血清检测两种新的HCC抗原的特异性。结果:相应的抗体主要见于HCC患者,检测10例HCC血清,阳性反应例数分别为8例及9例;胃癌5例,阳性反应分别为0例及1例;正常人28例各有阳性2例;乳癌10例,无阳性例数。结论:两种新的HCC抗原对HCC有高度特异性,可考虑作为HCC血清学诊断的指标之一。 相似文献
9.
Arend Mosaterd Jaap W. Deckers Arno W. Hoes Angelique Nederpel Albert Smeets David T. Linker Diederick E. Grobbee 《European journal of epidemiology》1997,13(5):491-502
Several scores based on symptoms and signs have been developed to assess the presence of heart failure. The goal of this study was to compare six heart failure scores in non-hospitalised subjects and to determine their usefulness in population based research. The scores were applied to 54 participants of a population based study. All underwent a complete medical examination, including chest X-ray, electrocardiography and Doppler echocardiography. Using all information available, a cardiologist, unaware of the results of the scores, clinically classified participants as having no, possible or definite heart failure. Sensitivity, specificity, predictive values and receiver operating characteristics were calculated, using the cardiologist's assessment as a gold standard. The cardiologist judged definite or possible heart failure to be present in 17 persons. All scores had a high sensitivity for the detection of definite heart failure, whereas the study of men born in 1913 and Walma's score had the highest sensitivity for the combination of possible and definite heart failure. Gheorgiade's and the Boston score had the highest positive predictive values. In conclusion, five of the six scores we studied are broadly similar in the detection of heart failure. The men born in 1913 score relies heavily on the assessment of dyspnea, resulting in a relatively large number of false positives. Although the scores are useful in detecting manifest heart failure, objective measurements of cardiac function appear necessary to reduce the false positive rate and accurately detect early stages of heart failure. 相似文献
10.
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