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91.
广东地区肝炎患者血清中庚型肝炎病毒RNA的检测   总被引:1,自引:0,他引:1  
目的了解庚型肝炎病毒(HGV)感染在不同临床类型肝炎患者中的存在状况。方法用逆转录-聚合酶链反应(RT-PCR)技术对721例肝炎患者血清进行了HGVRNA检测。结果发现80例HGVRNA阳性,以非甲、乙、丙、丁或戊型肝炎中阳性率为高;慢性丙型肝炎(HCV)和慢性乙型混合丙型肝炎(HBV+HCV)次之;在慢性重型肝炎和肝硬化时较低。结论庚型肝炎病毒在广东地区现症肝炎患者中有一定程度的流行  相似文献   
92.
目的 基于Lasso回归和列线图构建并验证川崎病患儿对丙种球蛋白耐药的预测模型,以期为临床诊疗提供帮助。方法 回顾性收集2014年7月—2020年7月西南医科大学附属医院收治的474例川崎病患儿的临床资料,采用Lasso回归分析筛选重要的临床因素构建Nomogram模型,通过绘制受试者工作特征(ROC)曲线、Calibration校准曲线及DCA曲线验证模型的区分度、校准度及临床有效性。结果 共纳入474例患儿资料,其中339例作为训练集,135例作为验证集。Lasso回归分析显示,心脏表现、心外并发症、首剂静脉注射免疫球蛋白使用时间、中性粒细胞比例、红细胞分布宽度-标准差、血小板压积、白蛋白、系统性免疫-炎症指数及C反应蛋白/白蛋白是川崎病患儿丙种球蛋白耐药的预测因素。基于上述预测因素构建Nomogram模型,并分别在训练集与验证集人群中进行验证。训练集ROC曲线下面积(AUC)为0.784(95%CI:0.701,0.867),当最佳阈值取0.045时,相应的特异性和敏感性分别为0.490(95%CI:0.434,0.546)和0.935(95%CI:0.849,1.000);验证...  相似文献   
93.
目的 探讨血脂水平与IgA肾病(IgAN)患者临床病理特征及补体3、4(C3、C4)水平的关系。方法 选取2018年1月—2021年12月在蚌埠医学院第一、二附属医院肾脏内科行肾活检诊断为IgAN的119例患者为研究对象,根据血脂水平将其分为异常组(84例)[甘油三酯(TG)≥ 2.26 mmol/L和/或总胆固醇(TC)≥ 6.22 mmol/L和/或高密度脂蛋白(HDL)< 1.04 mmol/L]、正常组(35例),比较两组患者临床病理特征,采用Pearson法分析血脂(TG、TC、HDL)与C3、C4水平的相关性。结果 异常组与正常组患者年龄、性别构成、收缩压、舒张压、血红蛋白、白蛋白、血肌酐、eGFR、血尿素氮、血尿酸、24 h尿蛋白、尿红细胞计数、CKD分期、肾小球球性硬化、肾小管萎缩面积、小球新月体、间质血管损伤程度、炎症细胞浸润及Lee氏分级比较,差异均无统计学意义(P >0.05)。异常组BMI、C3、C4水平高于正常组(P <0.05)。IgAN患者血清TG与C4呈正相关(r =0.247,P <0.05),与C3无相关性(r =0.102,P >0.05);血清TC与C4呈正相关(r =0.240,P <0.05),与C3无相关性(r =0.029,P >0.05);血清HDL与C3、C4无相关性(r =0.080和0.171,均P >0.05)。结论 部分IgAN患者存在血脂水平异常,且其血清TG、TC与C4水平呈正相关。  相似文献   
94.
High-resolution two-dimensional gel electrophoresis (2-DGE) was used to analyse plasma samples and partially purified cold agglutinins (CA) obtained from two selected patients. Both presented an acute hemolytic anemia with CA of high thermal amplitude, normal immunoglobulin levels, no detectable paraproteinemia, and no clinical evidence of a malignant B-cell disorder. The electrophoretograms of their plasma showed evident alternations of the "normal" protein profile, which were directly related to hemolysis (absence of the spots of haptoglobin and in one case of those of hemopexin), but no monoclonal gammopathy. The electrophoretograms of their purified CA revealed two clearly different spot patterns respectively corresponding to a monoclonal IgM and to polyclonal IgM. These results show that the clonality of CA associated with hemolytic anemia can be easily determined by 2-DGE. This technique may be very useful to discriminate chronic cold agglutinin disease in the early phase from "parainfectious" CA.  相似文献   
95.
Immunoglobulin mimicry by Hepatitis C Virus envelope protein E2   总被引:4,自引:0,他引:4  
Hu YW  Rocheleau L  Larke B  Chui L  Lee B  Ma M  Liu S  Omlin T  Pelchat M  Brown EG 《Virology》2005,332(2):538-549
Hepatitis C virus (HCV) establishes persistent infection in the majority of infected individuals. The currently accepted hypothesis of immune evasion by antigenic variation in hypervariable region 1 (HVR1) of glycoprotein E2 does not however, explain the lack of subsequent immune recognition. Here, we show that the N-terminal region of E2 is antigenically and structurally similar to human immunoglobulin (Ig) variable domains. E2 is recognized by anti-human IgG antibodies and also possesses common amino acid (aa) sequence features of the conserved v-gene framework regions of human Ig light chains in particular but also heavy chains and T cell receptors. Using a position specific scoring system, the degree of similarity of HVR1 to Ig types correlated with immune escape and persistence in humans and experimentally infected chimpanzees. We propose a unique role for threshold levels of Ig molecular mimicry in HCV biology that not only advances our concept of viral immune escape and persistent infection but also provides insight into host-dependent disease patterns.  相似文献   
96.
The incidence of upper respiratory tract infections (URTI) and salivary immunoglobulin A concentrations [IgAs] of nine individuals were examined during 12 weeks of moderate exercise training, and compared to ten sedentary controls. Changes in maximal oxygen uptake were assessed at initial, mid-point and final evaluations (T1–3), while changes in [IgAs] and salivary immunoglobulin concentration-salivary albumin concentration ratio ([IgAs]:[Albs]) were monitored at T1 and T3. During the 12 week period, symptoms of URTI were self-recorded daily. During the period of training the level of fitness significantly increased (P<0.05) in the exercise group. The number of days recording symptoms of influenza, but not of cold, and total light URTI symptoms was significantly reduced in the exercise group during the last weeks of training. A significant increase in [IgAs] and in [IgAs]:[Albs] was found in the exercise group after training. Both [IgAs] and [IgAs]:[Albs] were significantly related to the number of days showing symptoms of influenza (P<0.01) and the total number of days of sickness (P<0.05). These data provide quantitative support for the belief that regular, moderate exercise results in an increased [IgAs] at rest and [IgAs]:[Albs], which may contribute to a decreased risk of infection. Electronic Publication  相似文献   
97.
We have identified an autoantigen that is recognized by antibodies from an 18-year-old female with a history of recurrent infections who later in her clinical course developed Raynaud's phenomenon and telangiectasias. By indirect immunofluorescence (IIF), the index serum produced a unique cytoplasmic discrete speckled (CDS) staining pattern that partially colocalized with early endosome antigen 1 (EEA1) but not Golgi complex or other cytoplasmic organelles in HEp-2 cells. When HEp-2 cells were treated with 0.1 N HCl, the cytoplasmic speckled staining of the index serum was markedly decreased, suggesting that the reactive antigen was soluble. Western blot analysis showed a reactive approximately 97 kDa protein in a saline soluble protein preparation from HeLa cells. Mass spectrometric analysis of the excised 97 kDa band that was immunoprecipitated from HeLa cell extracts identified GRASP-1 as a possible target. The index serum and anti-GRASP-1 antibodies colocalized to structures in the cytoplasm of HEp-2 cells. Synthetic peptides representing the full-length GRASP-1 protein were used to identify reactive epitopes. Like many other cytoplasmic autoantigens, GRASP-1 has numerous coiled-coil domains throughout the protein with the exception of short segments at the amino and carboxyl terminus.  相似文献   
98.
临床诊断为非甲~戊型肝炎患者的病原学研究   总被引:8,自引:0,他引:8  
目的探讨临床诊断为非甲-戊型肝炎患者的病原学。方法 采用巢式PCR(nPCR)检测HBV、TTV、B19、和SENV DNA;用逆转录巢式PCR(RT-nPCR)检测HGV和HCV RNA。结果 60例临床诊断为非甲-戊型肝炎患者中,单独HBVDNA阳性30例(阳性率为50.0%),HBV和TTVDNA阳性10例(16.7%),HBV和B19DNA阳性6例(10.0%),HCVRNA、HBV和SENVDNA阳性1例(1.7%),单独HCVRNA阳性1例(1.7%),HCVRNA和B19DNA阳性1例(1.7%),HGVRNA无一例阳性,单独B19DNA阳性2例(3.3%)。单独TTVDNA阳性1例(1.7%),另8例(13.3%)上述病毒核酸均为阴性。HBV合并感染TTV或B19对其血清学生化指标无影响。结论HBV是临床诊断为非甲-戊型肝炎的主要病原,HGV、TTV、B19和SENV与非甲-戊型肝炎无关。  相似文献   
99.
We evaluated phenotypic and functional parameters of immune restoration of 27 HIV-infected patients on highly active antiretroviral therapy (HAART) (HIV-cases) with HIV-RNA levels below detectable limits at least during 18 months, and CD4+ cell per microliter higher than 500 at the moment of the study and lower than 300 anytime before. These patients were compared with 11 HIV-controls that never had less than 500 CD4+ cell per microliter and 20 healthy-controls (HIV seronegative subjects) in a cross-sectional study. HIV-cases had lower counts of naïve CD4+ than HIV-controls and healthy-controls. HIV-patients (both HIV-cases and HIV-controls) showed higher values of naïve and memory CD8+ counts than healthy-controls. TREC-bearing cell levels were significantly lower in HIV-cases than in healthy-controls. Peripheral blood mononuclear cells (PBMC) cultures, HIV-cases had lower values in proliferation to streptokinase (SK) and tetanus toxin (TT) than in healthy-controls. HIV-cases had lower IFN-γ and higher IL-5 production with pokeweed than healthy-controls (P < 0.01). However, IL-5 production of HIV-cases after TT stimulation was lower than in HIV-controls and healthy-controls. Total IgG and IgG1 levels were significantly higher in HIV-cases than in HIV-controls and healthy-controls. Also, IgM levels were significantly higher in HIV-cases than in healthy-controls. Nevertheless, IgG2 levels were significantly lower in HIV-cases and HIV-controls than in healthy-controls. The levels of specific Igs antipneumococcal capsular polysaccharide and TT were significantly lower in HIV-cases than in healthy-controls. HIV-patients with a previous state of severe-moderate immunosuppression normalizing their CD4+ counts have a incomplete immune reconstitution after HAART. Long-term consequences of this subclinical immune deficiency remain to be determined.  相似文献   
100.
目的 探讨新生儿C6PD缺陷病和晚发性维生素K缺乏症的危害与预防措施。方法 回顾分析1995-2000年儿内科住院的1周-2月(不含2月)的婴儿3104例次,其中病死56例。结果 1周-2月的小婴儿占住院患儿的19.34%,其中新生儿G6PD缺陷病239例,占7.70%;晚发性维生素K缺乏症92例,占2.96%。死因的第2、3位分别是晚发性维生素K缺乏症(13例,占23.21%)和新生儿C6PD缺陷病(12例,占21.43%),两者的病死率分别为14.13%和5.02%,极显著高于(x^2=17.59,P<0.01)或相近于(x^2=0.88,P>0.05)肺炎的3.57%。新生儿G6PD缺陷病合并感染占38.49%、低氧血症占23.35%、低血糖占19.25%、酸中毒占15.90%,继发胆红素脑病占13.81%。晚发性维生素K缺乏症出现抽搐占90.22%、胃肠、注射部位出血占60.89%;CT证实颅内出血占98.91%。结论 1周-2月的小婴儿约占住院患儿的两成,新生儿G6PD缺陷病和晚发性维生素K缺乏症的病死率均很高,两者是除肺炎外最主要的死因。提议制定并推广预防这2种疾病的常规措施,并参照国内外相应的现状拟出其具体内容。  相似文献   
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