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41.
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目的 :探讨淋巴细胞性胃炎 (LCG)的内镜、病理特点 ,以及根除幽门螺杆菌 (Hp)后对其的影响。方法 :分析 50例LCG的电子胃镜表现和病理所见 ,应用分级法评价淋巴细胞的浸润程度 ,应用PPI三联疗法根除Hp。结果 :LCG多见于中年男性 ,Hp感染率为84%。内镜特点 :90 %以上的病变位于胃窦和胃体的下段 ,特征性表现为多发性或弥漫性隆起样糜烂或脐样糜烂 ,共占 70 % ,可并发十二指肠球部病变 ,占 40 %。病理特点 :全部组织均有淋巴细胞浸润 ,淋巴滤泡形成占 58%。Hp根除后 ,41 .7%患者的胃镜表现胃黏膜大致正常 ;33 .3 %患者表现为黏膜稍充血水肿和花斑样改变 (P <0 .0 5) ;2 5%患者的糜烂灶明显减少 ,主要为散在的平坦性糜烂 (P <0 .0 5) ,而隆起样糜烂消失 ,淋巴滤泡完全消失 ;66.7%患者无淋巴细胞浸润 ,33 .3 %患者为 1级改变。根除Hp后 ,淋巴细胞分级为 0 .33± 0 .49级 (P <0 .0 0 1 )。结论 :LCG有一定的内镜和病理特点。根除Hp后 ,可明显减少淋巴细胞的浸润 ,且可治愈LCG。 相似文献
43.
显微镜下结肠炎(MC)是一种容易被错过的慢性腹泻的原因,多见于老年人,主要包括胶原性结肠炎和淋巴细胞性结肠炎两种亚型。最近报道MC的发病率呈上升趋势,其病因及机制尚未明确,但与免疫因素、药物特别是NSAID、感染、胆汁吸收障碍等有关。临床诊断需要病理活组织检查来明确。MC的治疗目的主要是缓解病情,应用氨基水杨酸、水杨酸亚铋、皮质类固醇类如布地奈德等治疗有效。 相似文献
44.
Foster ES Signs KA Marks DR Kapoor H Casey M Stobierski MG Walker ED 《Emerging infectious diseases》2006,12(5):851-853
We summarize the first reported case of acquired lymphocytic choriomeningitis virus (LCMV) infection in Michigan to be investigated by public health authorities and provide evidence of the focal nature of LCMV infection in domestic rodents. Results of serologic and virologic testing in rodents contrasted, and negative serologic test results should be confirmed by tissue testing. 相似文献
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46.
Summary The ultrastructure and the blood-brain-barrier (BBB) permeability were studied in mice suffering from lymphocytic choriomeningitis (LCM). Brains and meninges from mice suffering from LCM virus-induced lymphocytic choriomeningitis were studied by investigating the BBB function and by electron and light microscopy.The cellular exudate in the leptomeninges was located in the subarachnoid space, in arachnoidea and pia, and it was dominated by proliferated pial cells and mononuclear cells, most of which were lymphocytes, while there were only a few neutrophil granulocytes. Many intravascular lymphocytes were seen adhering to as well as penetrating the vessel walls. Many of these lymphocytes were morphologically compatible with T cells. Lymphocytes and larger mononuclear cells were also accumulated in the choroid plexus, and lymphocytes were present in the ventricular system with a tendency to adhere to ependymal epithelial cells. Inspection of the ultrathin sections incubated for horseradish peroxidase (HRP)-activity revealed that the overwhelming part of the peroxidase activity was localized in the extracellular space of the meningeal vessel walls and especially in the abundant intercellular fluid which, like the inflammatory cells, was found in the subarachnoid space in arachnoidea and in pia. In the neuropil, only very small quantities of reaction product were seen intercellularly in the most superficial layers of the cortex. The tight junctions were always intact, but the possibility of a non-demonstrable opening is discussed. Evaluation of the BBB permeability for 2-amino[1-14C]isobutyric acid (AIB) was made by quantitative autoradiography, and it was demonstrated convincingly that AIB concentrations in the subpial and perichoroidal tissues were markedly increased in diseased animals as compared to the controls.Our results seem to contradict previous theories on the cause of death resulting from the LCM disease. The findings presented here do not speak in favor of a pronounced brain edema, just as results obtained by us and others do not speak for the possibility of the death being caused by convulsive seizures with subsequent brain anoxia. However, our observations are compatible with the hypothesis that cytotoxic T cells may interact in vivo with virus-infected targets, which are essential for the regulation of the composition of the cerebrospinal fluid. On the other hand, the dysfunction of the BBB demonstrated adds a new element to the pathologic mechanism in a model for the study of virus-induced meningitis.Supported by grants from the Danish Medical Research Council (nos. 12-3142, 12-3597) and from the Foundation of Consul Ehrenfried Owesen and spouse 相似文献
47.
Lang KS Recher M Navarini AA Harris NL Löhning M Junt T Probst HC Hengartner H Zinkernagel RM 《European journal of immunology》2005,35(3):738-745
Persistence is a hallmark of infection by viruses such as HIV, hepatitis B virus, hepatitis C virus and LCMV. In the case of LCMV, persistence may often be associated with exhaustion of CD8(+) T cells. We demonstrate here that persistent antigen suppressed IL-7Ralpha expression and this correlated with T cell exhaustion and reduced expression of the anti-apoptotic molecule B cell leukemia/lymphoma 2 (Bcl-2). In contrast, exposure to short-lived antigen only temporarily suppressed IL-7Ralpha expression, failed to induce T cell exhaustion, and primed T cells. Persistent antigen also suppressed IL-7Ralpha expression on primed T cells and this correlated with exhaustion of a previously stable primed T cell population. These findings suggest that antigen longevity regulates T cell fate. 相似文献
48.
Maleki S Schlecht NF Keller C Diaz J Moss J Prystowsky MB Macian F Brandwein-Gensler M 《Head and neck pathology》2011,5(2):117-122
Lymphocytic host response (LHR) in the Risk Model is histologically quantified as the density of lymphocytes at the tumor interface (Brandwein-Gensler in Am J Surg Pathol, 34:676–688, 1; in, Am J Surg Pathol 29:167–178, 2). It is classified as strong, intermediate or weak, and is inversely associated with the risk of decreased time to disease progression. In this study, we test the hypothesis that strong LHR corresponds to a greater degree of adaptive cytotoxic T cell response as compared to moderate LHR. We studied resection specimens of primary oral squamous carcinoma classified as having either strong (n = 16), intermediate (n = 20) or weak (n = 4) LHR. CD20+, CD4+, & CD8+ cells were detected by immunohistochemistry and quantified at 40× with a grid; counting the 10 fields with the most lymphocytes at the tumor interface and within tumors. Mean counts/tumor were analyzed by the 2-sided T-test. Statistically significant differences were observed for interface CD8 cells with respect to strong versus moderate LHR, strong versus weak LHR, and moderate versus weak LHR, and tumor infiltrating CD8 cells with respect to strong versus weak LHR. Statistically significant differences were also observed for interface CD4 cells with respect to strong versus weak LHR, and moderate versus weak LHR. Statistically significant differences in interface B cell counts were seen with respect to strong versus weak LHR, and moderate versus weak LHR. Decreased CD8+ T cells were significantly associated with higher stage at presentation (P = 0.005); a direct, but nonsignificant correlation was seen between decreased CD8+ T cells and decreased survival time. Immune response at the tumor interface correlates with an adaptive T cell response; the degree of cytotoxic CD8+ cells infiltrate can distinguish between strong and intermediate LHR at the interface of oral carcinomas. 相似文献
49.
Gene transfer to the central nervous system provides powerful methodology for the study of gene function and gene–environment interactions in vivo, in addition to a vehicle for the delivery of therapeutic transgenes for gene therapy. The aim of the present study was to determine patterns of tropism exhibited by pseudotyped lentiviral vectors in the rat substantia nigra, in order to evaluate their utility for gene transfer in experimental models of Parkinson's disease. Isogenic lentiviral vector particles encoding a GFP reporter were pseudotyped with envelope glycoproteins derived from vesicular stomatitis virus (VSV), Mokola virus (MV), lymphocytic choriomeningitis virus (LCMV), or Moloney murine leukemia virus (MuLV). Adult male Lewis rats received unilateral stereotactic infusions of vector into the substantia nigra; three weeks later, patterns of viral transduction were determined by immunohistological detection of GFP. Different pseudotypes gave rise to transgene expression in restricted and distinct cellular populations. VSV and MV pseudotypes transduced midbrain neurons, including a subset of nigral dopaminergic neurons. In contrast, LCMV- and MuLV-pseudotyped lentivirus produced transgene expression exclusively in astrocytes; the restricted transduction of astroglial cells was not explained by the cellular distribution of receptors previously shown to mediate entry of LCMV or MuLV. These data suggest that pseudotyped lentiviral vectors will be useful for experimental gene transfer to the rat substantia nigra. In particular, the availability of neuronal and astrocytic-targeting vectors will allow dissociation of cell autonomous and cell non-autonomous functions of key gene products in vivo. 相似文献
50.
JS Jeong HK Kim CR Lee S Park JH Park SW Kang JJ Jeong KH Nam WY Chung CS Park 《Journal of Korean medical science》2012,27(8):883-889
The study aimed to identify the clinical characteristics of coexisting chronic lymphocytic thyroiditis (CLT) in papillary thyroid carcinoma (PTC) and to evaluate the influence on prognosis. A total of 1,357 patients who underwent thyroid surgery for PTC were included. The clinicopathological characteristics were identified. Patients who underwent total thyroidectomy (n = 597) were studied to evaluate the influence of coexistent CLT on prognosis. Among the total 1,357 patients, 359 (26.5%) had coexistent CLT. In the CLT group, the prevalence of females was higher than in the control group without CLT (P < 0.001). Mean tumor size and mean age in the patients with CLT were smaller than without CLT (P = 0.040, P = 0.047, respectively). Extrathyroidal extension in the patients with CLT was significantly lower than without CLT (P = 0.016). Among the subset of 597 patients, disease-free survival rate in the patients with CLT was significantly higher than without CLT (P = 0.042). However, the multivariate analysis did not reveal a negative association between CLT coexistence and recurrence. Patients with CLT display a greater female preponderance, smaller size, younger and lower extrathyroidal extension. CLT is not a significant independent negative predictive factor for recurrence, although presence of CLT indicates a reduced risk of recurrence. 相似文献