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941.
Rapid detection of soluble F1 capsular antigen in serum, bubo fluid or urine of patients proved to be a valuable tool in the presumptive diagnosis of plague. We evaluated a F1 capsular antigen capture ELISA resembling a commercially available test kit. The minimal detectable concentration was 4 ng/ml. The specificity was 100% when investigating 47 sera from healthy Malagasy subjects and 98.4% when 365 sera from German blood donors were studied. Sensitivity was determined on sera (n=11) and buboes (n=18) from bacteriologically confirmed Malagasy plague patients. Sensitivity was 90.1% for serum and 100% for buboes. A standardized F1 capsular antigen capture ELISA test kit might be well suited for the early detection of plague particularly in non-endemic areas where clinical microbiological laboratories have only limited access to alternative techniques for rapid identification of Yersinia pestis.  相似文献   
942.
Formann AK 《Biometrics》2003,59(1):189-196
This is in response to Garrett and Zeger (2000, Biometrics 56, 1055-1067) who, within the Bayesian framework, developed mainly graphical methods for latent class model diagnosis. Possible problems with this approach, and with its application to both generated and empirical data, are pointed out. The impact of the proposed tools cannot be understood by their reader, as no comparisons are made to results obtainable using established methods for latent class model diagnosis; this applies especially to overall goodness-of-fit tests, for which alternatives (bootstrap, Rudas-Clogg-Lindsay index of fit) are mentioned. Further, in one case of generated data, the methods proposed by Garrett and Zeger seem to give problematic results as to identifiability; in the case of the empirical data on major depression, they lead to accepting a suboptimal three-class model. In the latter case, one can be rather sure that an identifiable, well-fitting latent class model could have been identified--if Garrett and Zeger had also considered restricted latent class models.  相似文献   
943.
Over a one year period (November 2000-December 2001), clinical specimens from 189 dogs and 38 cats, from the city of Fortaleza, Ceará, Brazil, were examined at the Specialized Medical Mycology Center at the Federal University of Ceará to detect animals with dermatophytoses. The mycological analyses were conducted by direct microscopy and by fungal culture on Sabouraud agar, Sabouraud chloramphenicol agar and Mycosel agar. Dermatophytes were isolated from 27 of the 189 (14.3%) canine specimens and 14 of the 38 (36.8%) feline specimens. The identified dermatophytes were Microsporum canis (95%), M. gypseum (2.5%) and Trichophyton mentagrophytes var. mentagrophytes (2.5%). Microsporum canis was the most common species isolated (92.6% and 100%, for dogs and cats respectively). The percentage of positive direct microscopic examinations of clinical specimens and positive cultures was 61%. There was a high proportion of positive cultures from cats less than 1 year of age, but in dogs no significant differences were detected. There were no significant differences between the sexes. Dermatophytes were more frequently isolated in March, April and May, but no significant differences were detected in the seasonal distribution of canine and feline dermatophytoses.  相似文献   
944.
We developed a microscopy method for the detection of fungal cells in peripheral blood, termed blood lysate staining, using an approximately 5x5 mm dotted blood lysate. This method was able to detect the emerging fungal pathogen Trichosporon asahii in murine models of systemic fungal infection and fungemia in patients quickly and at minimal cost. Pathogenic yeasts were successfully detected in 6 of 8 blood samples which were taken from feverish immunocompromised patients who were clinically suspected of having fungal infections. Fungal cells were observed as ovoid to elongated, 3x3 to 7x10 microm, and occurred singly, budding, and in short chains and clusters in a periodic acid-Schiff-stained blood smear. The yeast cells were easily distinguished from blood-cell debris by their size, shape and smooth yet rigid outline.  相似文献   
945.
黄滨  唐慰萍 《病毒学报》2000,16(3):258-261
以Epstein-Barr病毒(EBV)DNA聚合酶为抗原,建立了简便、快速、敏感和特异的鼻咽癌诊断方法。构建原表达载体pRSET-DNA聚合酶及其亚克隆PRSET-A1和BL21(DE3)中表达的产物,经Western-blot检测其抗原性并用于检测鼻咽癌(nasopharyngeal carcinoma,NPC)病人血清中的抗体。在DPC病人血清中存在抗EB病毒DNA聚合酶的IgG抗体,并证明  相似文献   
946.
947.
IntroductionMonitoring early diagnosis is a priority of cancer policy in England. Information on stage has not always been available for a large proportion of patients, however, which may bias temporal comparisons. We previously estimated that early-stage diagnosis of colorectal cancer rose from 32% to 44% during 2008–2013, using multiple imputation. Here we examine the underlying assumptions of multiple imputation for missing stage using the same dataset.MethodsIndividually-linked cancer registration, Hospital Episode Statistics (HES), and audit data were examined. Six imputation models including different interaction terms, post-diagnosis treatment, and survival information were assessed, and comparisons drawn with the a priori optimal model. Models were further tested by setting stage values to missing for some patients under one plausible mechanism, then comparing actual and imputed stage distributions for these patients. Finally, a pattern-mixture sensitivity analysis was conducted.ResultsData from 196,511 colorectal patients were analysed, with 39.2% missing stage. Inclusion of survival time increased the accuracy of imputation: the odds ratio for change in early-stage diagnosis during 2008–2013 was 1.7 (95% CI: 1.6, 1.7) with survival to 1 year included, compared to 1.9 (95% CI 1.9–2.0) with no survival information. Imputation estimates of stage were accurate in one plausible simulation. Pattern-mixture analyses indicated our previous analysis conclusions would only change materially if stage were misclassified for 20% of the patients who had it categorised as late.InterpretationMultiple imputation models can substantially reduce bias from missing stage, but data on patient’s one-year survival should be included for highest accuracy.  相似文献   
948.
摘要 目的:探讨超声在完全与不完全川崎病(Kawasaki Disease,KD)患儿冠状动脉病变(Coronary artery lesions,CAL)评估中的应用价值。方法:2019年6月到2021年5月选择在西安医学院第二附属医院住院诊治的83例川崎病患儿,其中完全川崎病患儿43例(完全组),不完全川崎病患儿40例(不完全组)。所有患儿都给予超声检查,评估两组的临床表现、血液学指标、冠状动脉病变情况以及超声的诊断价值。结果:完全组的球结膜充血、皮疹、口唇破裂、手足硬肿、颈部淋巴结肿大等发生率高于不完全组(P>0.05)。两组的白细胞计数、血红蛋白对比差异有统计学意义(P<0.05),C反应蛋白、血小板、白蛋白对比差异无统计学意义(P>0.05)。完全组的冠状动脉病变发生率为60.5 %,高于不完全组的27.5 %(P<0.05)。在83例患儿中,超声诊断为完全川崎病42例,不完全川崎病41例,超声对完全与不完全川崎病患儿的鉴别诊断敏感性与特异性为97.7 %(42/43)和100.0 %(40/40)。结论:完全与不完全川崎病患儿在临床表现、冠状动脉病变与实验室检测指标上都存在一定的差异,超声能鉴别诊断完全与不完全川崎病患儿的敏感性与特异性都比较好。  相似文献   
949.
摘要 目的:探讨血清嗜酸性粒细胞(EOS)表达水平与鼻腔鼻窦内翻性乳头状瘤(SNIP)病理的相关性。方法:选取我院2016年1月至2020年1月收治的63例SNIP患者作为研究对象,依照所有患者EOS水平将其分为低EOS组、中EOS组、高EOS组,对比三组患者的临床病理特征,并分析EOS表达水平与SNIP病理的相关性。行手术治疗后将63例患者分为预后不良组与预后良好组,对比两组患者的临床相关指标,并分析EOS表达水平对SNIP的预后预测价值。结果:三组患者临床分期、病理诊断对比差异显著(P<0.05);以EOS表达水平进行分级:高水平:>300个/μL,中水平:100-300个/μL,低水平:<100个/μL。Spearman相关分析结果显示:性别、年龄、病灶位置与EOS表达水平无明显相关性(P>0.05),临床分期、病理诊断与EOS水平呈负相关(P<0.05);预后良好组与预后不良组患者PLT水平对比无明显差异(P>0.05),预后两组患者L、EOS水平明显高于预后不良组,N、PLR、NLR低于预后不良组(P<0.05);logistic回归分析结果表明:NLR、EOS为SNIP的预后独立预测因素(P<0.05)。结论:SNIP患者的临床分期、病理诊断与EOS表达水平呈负相关,且应用NLR和EOS可对SNIP术后复发情况进行预测,因此,可以考虑应用EOS表达水平对SNIP进行诊断与治疗效果判定。  相似文献   
950.
摘要 目的:探讨计算机断层扫描(CT)增强结合多b值弥散加权成像(DWI)对胆总管炎性狭窄与肿瘤性病变所致狭窄的鉴别诊断价值。方法:回顾性分析2017年4月-2021年10月于我院经手术病理或逆行胰胆管造影(ERCP)证实为胆总管炎性或肿瘤性狭窄的106例患者的临床资料,术前均行CT增强、多b值(200、400、600、800、1000 s/mm2)DWI的磁共振成像(MRI)检查并测量其多b值DWI下的ADC值,分析胆总管炎性狭窄与肿瘤性狭窄的影像表现,比较CT增强、多b值DWI单独及结合对胆总管炎性狭窄与肿瘤性狭窄的鉴别诊断效能。结果:106例患者中胆总管炎性狭窄共43例,肿瘤性狭窄患者共63例。当b值分别为200、400、600、800、1000 s/mm2时,胆总管肿瘤性病变ADC值均显著低于胆总管炎性狭窄,差异均具统计学意义(P<0.05),随着b值增加,其ADC值均减小。当b值分别取200、400、600、800、1000 s/mm2时,对应曲线下面积(AUC)分别为0.574、0.705、0.715、0.781、0.726,b值为800 s/mm2时诊断胆总管炎性狭窄与肿瘤性狭窄的效能最佳。CT增强结合多b值DWI对比CT增强或多b值DWI对胆总管炎性狭窄与肿瘤性狭窄的诊断效能最佳。结论:当多b值DWI取800 s/mm2时,CT增强结合多b值DWI可以显著提高胆总管炎性狭窄与肿瘤性狭窄的鉴别诊断价值,具有一定的临床应用价值。  相似文献   
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