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21.
目的 检测黑龙江省2019—2021年肾综合征出血热(hemorrhagic fever with renal syndrome, HFRS)疑似患者血清标本中的汉坦病毒急性期和恢复期抗体水平,为该疾病防控提供科学依据。方法 应用酶联免疫吸附法对采集到的肾综合征出血热疑似患者急性期血清样本进行汉坦病毒IgM抗体检测,对恢复期血清标本进行IgM单抗体、IgG单抗体检测,使用SPSS 19.0软件对各年份间患者急性期血样IgM抗体阳性率进行χ2检验分析,使用EpiData 3.1和Excel2003软件对患者性别、职业、年龄、发病日期及初诊间隔时间数据进行整理分析。结果 共检测肾综合征出血热疑似患者急性期血清351份,恢复期血清208份。急性期血清标本IgM抗体阳性317份,阳性率为90.31%,各年份之间患者急性期IgM抗体阳性率差异无统计学意义(χ2=0.895,P=0.639)。患者恢复期血清IgM单抗体阳性32份(15.39%);血清IgG单抗体阳性28份(13.46%);IgM、IgG抗体双阳性148份(71.15%)。男女患者性别比4... 相似文献
22.
Barabas AZ Cole CD Barabas AD Cowan JM Yoon CS Waisman DM Lafreniere R 《International journal of experimental pathology》2004,85(4):201-212
Summary Diffuse distribution of small, faintly staining, beaded deposits of rat immunoglobulin M (IgM) around the glomerular capillary blood vessels, and a more intensely staining larger deposition in the mesangium, were observed on the kidney sections of normal rats. As glomerular-fixed nephritogenic antigens are known to be present on the epithelial aspect of the glomerular basement membrane (GBM), especially at the soles of foot processes and at the slit pores, it was assumed that the IgM antibodies were directed against these antigens. Investigation by immunofluorescent antibody double-staining techniques of rat kidney sections obtained from normal and rabbit anti-FX1A-injected rats stained for the nephritogenic antigen showed that a number of antigenic sites in the glomeruli and in the mesangium shared antibody hits by heterologous rabbit IgG and autologous rat IgM antibodies. Most sites in the glomeruli stained specifically for rat IgM or rabbit IgG, but preferentially for the latter. The intensely fluorescent mesangial deposits stained mainly for rat IgM, indicating that at these sites the antigenic material was virtually saturated, while areas at the entry to the mesangial space also stained for rabbit IgG, indicating that at these locations free nephritogenic epitopes were still available for reaction with the anti-FX1A antibody. Western blot analysis have shown that the rabbit anti-rat FX1A IgG and the rat anti-rat KF3 IgM antibodies are directed against the same renal tubular-derived antigen with a molecular weight of 70,000. These experimental findings collectively demonstrate that the heterologous IgG and autologous IgM antibodies are directed against the same nephritogenic antigen, which is found in the glomeruli, the mesangium and the proximal convoluted tubules. Thus, the IgM autoantibody has a possible physiological role but, in addition, there is evidence of active immunophagocytic events, manifested in a rapid and continuous entrapment and expulsion of macromolecules after their processing by the mesangial cells of normal and passive Heymann nephritis rats. 相似文献
23.
散发性戊型肝炎病毒感染的诊断 总被引:4,自引:4,他引:4
用基因工程重组的戊型肝炎病毒基因结构区第二码框架和第二读码框架具有免疫表位的嵌合抗原,建立了间接酶联免疫法,检测散发性急性肝炎病人血清中抗-HEVIgG和IgM抗体。在46例急性肝炎病人中出抗-HEVIgG抗体阳性7例,阳性率为15.22%,7例IgG抗体阳性中,有5例IgM抗体也阳性,占71.4%。 相似文献
24.
Mutations in activation-induced cytidine deaminase in patients with hyper IgM syndrome 总被引:7,自引:0,他引:7
Minegishi Y Lavoie A Cunningham-Rundles C Bédard PM Hébert J Côté L Dan K Sedlak D Buckley RH Fischer A Durandy A Conley ME 《Clinical immunology (Orlando, Fla.)》2000,97(3):203-210
Recent studies have shown that mutations in a newly described RNA editing enzyme, activation-induced cytidine deaminase (AID), can cause an autosomal recessive form of hyper IgM syndrome. To determine the relative frequency of mutations in AID, we evaluated a group of 27 patients with hyper IgM syndrome who did not have defects in CD40 ligand and 23 patients with common variable immunodeficiency. Three different mutations in AID were identified in 18 patients with hyper IgM syndrome, including 14 French Canadians, 2 Lumbee Indians, and a brother and sister from Okinawa. No mutations were found in the remaining 32 patients. In the group of patients with hyper IgM syndrome, the patients with mutations in AID were older at the age of diagnosis, were more likely to have positive isohemagglutinins, and were less likely to have anemia, neutropenia, or thrombocytopenia. Lymphoid hyperplasia was seen in patients with hyper IgM syndrome and normal AID as well as the patients with hyper IgM syndrome and defects in AID. 相似文献
25.
Shobha D. Chitambar Vaishali S. Tatte Ram Dhongde Vijay Kalrao 《Journal of medical virology》2008,80(12):2169-2176
Recently, rotavirus antigenemia and viremia have been identified in patients with acute gastroenteritis. This study examined rotavirus viremia in children hospitalized for acute gastroenteritis in order to establish its association with fecal shedding of rotavirus, infecting genotypes and antibody marker of acute infection. Thirty‐one pairs of stool–serum specimens were collected from November 2004 to February 2005 together with clinical information. All paired specimens were screened for rotavirus RNA by RT‐PCR using the VP6 gene primers. All stool and serum specimens were tested for rotavirus antigen and anti‐rotavirus IgM respectively by ELISA. Sixteen of 31 stool–serum pairs showed the presence of rotavirus RNA. Nine stool and two serum specimens were positive only by RT‐PCR. The total positivity in rotavirus RNA was significantly higher in both stools (80.6%) and sera (58.1%) than that of stool antigen (38.7%) and anti‐rotavirus IgM (25.8%) (P < 0.01). All PCR positive paired specimens were typed for the VP7 (G) and VP4 (P) genes. Five of sixteen pairs could be typed for both genes. Three of the five pairs showed concordance (G2P[4]/G2P[4]) while two showed discordance (G12P[8]/G2P[4], G8P[4]/G2P[4]) in the genotypes detected in stool and serum specimens respectively. The study documents a high frequency of rotavirus viremia in patients with acute diarrhea. The discordance of rotavirus strains at the genotypic level in the serum and stool of individual patients with diarrhea suggests the susceptibility of extra‐intestinal sites for rotavirus infection and the possibility of differential dissemination of rotavirus strains from the intestine. J. Med. Virol. 80:2169–2176, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
26.
PENA方法的建立及与ELISA IgM检测CMV的比较 总被引:1,自引:0,他引:1
目的 介绍一种敏感、稳定、快速、简便的实验室检测CMV的方法 ,同时探讨该种新方法与ELISA检测CMV方法的优、缺点。方法 对 5 5 2例病人应用间接荧光免疫法测定细胞核中的特异病毒早期抗体 (PENA)和ELISA法测定IgM抗体。结果 PENA方法 :强阳性 88例 ,阳性率 15 4 9% ,弱阳性 2 73例 ,阳性率 5 9 4 6 % ;ELISA -IgM方法 :阳性 34例 ,阳性率6 16 %。结论 PENA方法操作简便 ,与ELISA方法相比较 ,可对CMV感染进行早期测定及诊断 ,并可区分既往感染和即时感染 ,具有敏感性和稳定性 ,是测定小儿CMV感染的一种较好的方法 相似文献
27.
本文用自制CMV抗原和生物素-链霉亲和素系统试剂,通过最适条件的对比,建立了检测人血清中抗巨细胞病毒IgM、IgA类抗体的BSA-ELISA,并与普通ELISA作比较,结果表明,BSA-ELISA的非特异性吸附明显低于普通ELISA,与普通ELISA相比,抗体效价分别提高5和7倍,阳性率分别提高68%和153.5%。在实际工作中曾用BSA-ELISA检测临床样品165份,就所得结果进行分析。表明BSA-ELISA检测CMVIgM和IgA可提高特异性和灵敏度,值得推广应用。 相似文献
28.
A solid-phase radioimmunoassay (RIA) has been developed for the detection of human rotavirus-specific IgA, IgG, and IgM antibodies. Nebraska calf diarrhea virus grown in LLC-MK2 cell cultures in the presence of trypsin was directly adsorbed onto polystyrene balls, and antibodies that attached to the virus-coated balls were detected by subsequent binding of 125I-labeled antibodies specific to human alpha, gamma or mu chains of human Iga, IgG, or IgM immunoglobulins. A total of 116 serum specimens from 58 adult patients were tested. Binding ratios between the positive and the negative serum varied between 5 and 15, occasionally being 20 or more in the IgA and IgG assays, but rarely exceeding 3 in the IgM assay. The RIA was found to be more sensitive in detecting antibodies to rotavirus than the complement fixation (CF) test, the RIA titers obtained being 50--100 times as high as the CF titers. The method described offers a possibility of evaluating the immune response to human rotavirus and of detecting recent infection. 相似文献
29.
Airway hyper-reactivity mediated by B-1 cell immunoglobulin M antibody generating complement C5a at 1 day post-immunization in a murine hapten model of non-atopic asthma 下载免费PDF全文
Kawikova I Paliwal V Szczepanik M Itakura A Fukui M Campos RA Geba GP Homer RJ Iliopoulou BP Pober JS Tsuji RF Askenase PW 《Immunology》2004,113(2):234-245
Contact skin immunization of mice with reactive hapten antigen and subsequent airway challenge with the same hapten induces immediate airflow obstruction and subsequent airway hyper‐reactivity (AHR) to methacholine challenge, which is dependent on B cells but not on T cells. This responsiveness to airway challenge with antigen is elicited as early as 1 day postimmunization and can be adoptively transferred to naïve recipients via 1‐day immune cells. Responses are absent in 1‐day immune B‐cell‐deficient JH?/? mice and B‐1 B‐cell‐deficient xid male mice, as well as in recipients of 1‐day immune cells depleted of cells with the B‐1 cell phenotype (CD19+ B220+ CD5+). As B‐1 cells produce immunoglobulin M (IgM), we sought and found significantly increased numbers of anti‐hapten IgM‐producing cells in the spleen and lymph nodes of 1‐day immune wild‐type mice, but not in xid mice. Then, we passively immunized naive mice with anti‐hapten IgM monoclonal antibody and, following airway hapten challenge of the recipients, we showed both immediate airflow obstruction and AHR. In addition, AHR was absent in complement C5 and C5a receptor‐deficient mice. In summary, this study of the very early elicited phase of a hapten asthma model suggests, for the first time, a role of B‐1 cells in producing IgM to activate complement to rapidly mediate asthma airway reactivity only 1 day after immunization. 相似文献
30.
Detection by ELISA of IgA and IgM antibodies in secretion and IgM antibodies in serum in primary lower respiratory syncytial virus infection 总被引:3,自引:0,他引:3
Twenty-six infants and children with primary lower RS virus infection, diagnosed by the detection of RS virus in nasopharyngeal secretion (NPS) by use of immunofluorescent antibody (FA) technique, were studied with respect to the presence of IgA and IgM antibodies. Samples of NPS and serum obtained during the first 3-4 months following the beginning of illness, were investigated. Employing a reverse ELISA technique, we found IgM antibodies in the acute, but not during the convalescent, phase of illness in NPS from 20 of the patients and in serum from 21 of the patients. The majority of the IgM antibody conversions observed occurred in NPS as well as in serum on days 5-8 following the illness. RS virus IgA antibodies, also detected by a reverse ELISA technique, were demonstrated in NPS in 22 of the patients, with antibody conversions being found in 19 of the patients on days 5-8 following the beginning of the illness. Two patients still had IgA antibodies in NPS approximately 3 months FSOI. By comparison, RS virus was detected in acute-phase NPS by double-antibody sandwich ELISA in 25 of the 26 patients investigated. 相似文献