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91.
SJL/J mice challenged with myelin basic protein (MBP) in complete Freund's adjuvant (CFA) developed only mild chronic-relapsing experimental allergic encephalomyelitis (EAE) with very low incidence. However, treatment of challenged mice with anti-infeferonγ (IFN-γ) monoclonal antibody (mAb) determined severe disease in all cases. Similarly, in passive EAE, the addition of anti-IFN-γ to the in vitro MBP-activated cells at the time of transfer led to significant disease exacerbation in all recipients. The disease enhancing effect was observed only when the mAb was given at the time of active challenge or of passive transfer, but not at later times. Anti-interleukin-2 (IL-2) antibody had only a marginal effect in the active induction, but drastically reduced the manifestations of passive EAE, even when mixed with a disease-enhancing dose of anti-IFN-γ. These findings support the notion that IL-2 is required for disease induction whereas IFN-γ plays a disease-limiting role early in the development of EAE.  相似文献   
92.
Summary This is obviously the first report on a case with a spontaneous sensu strictu relapsing variant of human immunodeficiency virus (HIV)-related polyneuropathy. Its manifestation preceded LAS. Intrathecal HIV-antibodies developed between the most severe third and fourth episode. Analysis of sural nerve biopsy was consistent with a multifocally accentuated chronic inflammatory demyelination, characterized by unusual onion bulb-like Schwann cell formations with irregular voluminous layers, electron density, aggregation of filaments, multiple indented nuclei, and numerous enclosed collagen pockets. A direct or immune-mediated indirect specific influence on Schwann cell morphology by HIV might be discussed. Virus-like particles and ultrastructural markers of HIV were not detectable.  相似文献   
93.
94.
This study was undertaken to explore whether intervention withheparin and aspirin (H/A) in selected patients undergoing in-vitrofertilization (TVF) and embryo transfer could improve fecundityrates. Specifically, it explored the possibility that womendiagnosed with organic pelvic disease who demonstrated antiphospholipidantibodies (APA) could benefit from H/A administration in asimilar manner to that used in patients with recurrent pregnancyloss. We used an enzyme–linked immunosorbent assay forsix different phospholipids to identify patients who expressedAPA before they underwent IVF/embryo transfer. This study wasconfined to the first IVF/embryo transfer cycle that followedassessment of APA status and accordingly, the number of IVF/embryotransfer cycles corresponds with the number of patients treated.APA seropositive patients were treated with aspirin, 81 mg orallyq.d., and heparin 5000 IU s.c. b.i.d., beginning on day 1 ofcontrolled ovarian stimulation. The endpoint for success wasa live birth or an ultrasound confirming fetal cardiac activity(a viable pregnancy). The prevalence of APA in patients diagnosedwith organic pelvic disease (53%) was much higher than in thosewithout female pathology (14%). The administration of H/A toAPA seropositive patients significantly (P < 0.05) improvedthe viable pregnancy rate (49%) compared to the untreated APAseropositive group (16%). The viable pregnancy rate for APAseropositive women treated with H/A was also significantly (P< 0.001) higher than for untreated APA seronegative patients(27%). We conclude that all women undergoing IVF/embryo transfershould be tested for APA prior to initiating ovarian stimulation,and those with APA seropositivity should be treated with H/A.  相似文献   
95.
目的探讨抗磷脂综合征(APS)患者治疗前后的抗心磷脂抗体(ACA)的定性定量水平及其对妊娠结局的影响,比较ACA定量与定性的准确性和灵敏度。方法对我院门诊APS孕妇40例,用定性定量方法监测治疗前后ACA的变化及对治疗后妊娠结局的影响。结果(1)定量方法检测治疗前的ACA-IgG和ACA-IgM滴度分别为(67.63±2.53)U和(49.40±3.64)U;治疗后的ACA-IgG和ACA-IgM滴度分别为(23.87±1.54)U和(21.60±2.59)U,两者比较,治疗后的ACA滴度水平显著低于治疗前水平(P<0.01)。定性方法检测APS孕妇,治疗后ACA转阴率为75%。(2)40例孕妇经治疗均娩出正常新生儿,ACA定量转阴组的妊娠并发症发生率(0.6%)较未转阴组(14.3%)显著降低(P<0.01)。ACA定性定量同时阴性组的妊娠并发症发生率(0.9%)较定性阴性而定量阳性组(7.1%)显著降低(P<0.05)。(3)治疗后30例孕妇ACA定性转阴,但其ACA-IgG和ACA-IgM滴度分别为(27.63±6.05)和(20.13±5.60)U/ml。结论ACA定性与定量均能准确有效的监测ACA水平,反映疗效及预测预后;ACA定量是一种较定性更准确灵敏的诊断监测方法。  相似文献   
96.
We report the case of a woman with refractory celiac disease who developed abnormal spontaneous movements of the extremities and face consistent with myorhythmia. Investigation led to a diagnosis of encephalitis, confirmed by postmortem examination. The movements were likely caused by nonparaneoplastic encephalitis associated with refractory celiac disease. Etiologic and diagnostic considerations and treatment options are discussed.  相似文献   
97.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a genetically transmitted cerebrovascular disease. Typically, the first clinical manifestation is migraine and the full clinical spectrum of the disease with recurrent strokes of the subcortical type, cognitive, and mood disorders is seen during the fourth and fifth decades of life. Vascular risk factors are usually absent in CADASIL patients and the diagnosis of the disease is particularly suspected in young adults with cerebrovascular events of unknown cause, diffuse leukoencephalopathy on computed tomography or magnetic resonance imaging, and a history of cerebrovascular diseases or dementia in many family members. We describe three Italian CADASIL patients who presented to medical attention for cerebrovascular events occurred after the age of 55 and had, in addition to hypertension and hyperlipidemia, thrombophilic risk factors such as hyperhomocysteinemia, elevated levels of lipoprotein(a), and antiphospholipid antibodies. Symptoms possibly related to cortical involvement, such as dysphasia and visual field deficits, were reported by two of these patients. We conclude that a diagnosis of CADASIL should not be disregarded in patients with vascular risk factors and presenting with symptoms not immediately referable to subcortical damage at ages more advanced than commonly reported.  相似文献   
98.
抗心磷脂抗体与脑血管病关系的研究   总被引:2,自引:0,他引:2  
目的:探讨抗心磷脂抗体(aCL)与脑血管病(CVD)的关系。方法:检测266例缺血性脑血管病(ICVD)患者和73例脑出血(CH)患者血清aCL。结果:ICVD患者aCL阳性率高于对照组(P<0.01),且IgG型aCL比IgM型aCL阳性率升高(P<0.01)。CH患者aCL阳性率高于对照组(P<0.01)。ICVD组aCL阳性率与CH组比较无显著性差异(P>0.05),ICVD组、CH组和对照组不同性别间aCL阳性率无显著性差异(P>0.05)。结论:aCL可作为CVD危险性增加的指标,对CVD的预测有一定意义,包括ICVD和CH患者,aCL阳性率男女性别之间无差异。  相似文献   
99.
Autoimmune mechanisms are postulated to play a role in the development and progression of dysimmune neuropathies (DN). We investigated the relation between lymphocyte number and marker expression, and disease activity in 20 patients with DN under intravenous immunoglobulins (IVIg) treatment. B- and T-lymphocyte markers were studied by flow cytometry of the expression of CD5, CD25, CD23 and CD38 markers on B cells and of CD3, CD4 and CD8 markers, respectively. These parameters were compared with those obtained from matched healthy volunteers. The proportions of CD38+ B cells were higher in patients compared with those of controls. Proportions of activated CD4+ and CD8+ T cells were comparable in peripheral blood mononuclear cells of patients and controls, but a significant reduction of the absolute numbers of CD3+, CD4+ and CD8+ cells were observed in DN patients. The percentages of CD25+ memory T cells were instead significantly increased in DN patients. Lastly, T-cell reduction and the CD19/CD38 ratio over total B (CD19+) cells directly correlated with a poor response to IVIg therapy. In DN, whereas T-cell number is reduced, activated T and B cells are increased, thus suggesting an intrinsic defect of the immune response.  相似文献   
100.
作者应用免疫细胞化学法研究了HFRS尸检内分泌及其有关组织中病毒抗原的分布,病毒抗原阳性细胞与病变的关系,病变的类型及病毒感染对胰腺内胰岛素表达的影响,所用的一抗有抗肾综合征出血热(HFRS)病毒糖蛋白(G_2),核蛋白(NP)及血凝素(HA)抗原的单克隆抗体(15种)和多克隆抗体(PAb)以及抗胰岛素(INS)单克隆抗体。结果显示,内分泌组织中有两种染色形态的病毒抗原,一种是胞浆弥漫染色的抗原,为G_2,NP或HA阳性,阳性细胞弥漫分布,另一种是以病毒包涵体(IB)形式出现的颗粒性抗原,MAbs染色多为实性,PAb染色多为空泡状。在9例胰腺组织中,有4例几乎在所有腺上皮细胞和少数胰岛细胞均为IB阳性,但PAb染色可在胰岛细胞中显示出空泡状IB。在其它内分泌组织中,IB只在少数细胞中出现。抗原阳性细胞很少出现坏死,但在脑垂体及肾上腺灶性或片状凝固性坏死区域也有弥漫性抗原阳性及IB存在。胰腺组织的胰岛素染色显示,除1例胰岛INS强阳性,其余8例均有明显的INS染色减弱及阳性细胞减少的表现。结果提示,内分泌组织中有两种病变,即以IB为特征的病毒直接感染引起的细胞病变,是病毒的弱致病变作用,该病变可能对细胞的内分泌功能产生影响;另一种病变是组织的灶性或大片性同步性凝固性坏死,是继发于病毒感染后的出血和休克,该病变会  相似文献   
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