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1.
习洋  陶泽璋 《疑难病杂志》2020,(2):207-211,216
慢性鼻窦炎(CRS)是一种常见的慢性非特异感染性鼻部疾病,病理分型主要分为Th2细胞介导的嗜酸性粒细胞性鼻窦炎(ECRS)和Th1细胞介导的非嗜酸性粒细胞性鼻窦炎(非ECRS)2种表型。欧洲国家CRS患病人群主要表现为ECRS,而随着亚洲国家的急剧工业化发展,其ECRS的比例也在急剧增加。ECRS发病机制复杂,涉及多种免疫细胞和相关因子相互作用。其治疗方法包括抗生素、激素药物治疗及手术治疗等,但仍有部分患者症状难以改善或存在复发的风险。Ⅱ型固有淋巴样细胞(ILC2s)是一种非B、非T的新型淋巴细胞,与Th2免疫应答关系密切。文章就ILC2s在ECRS发病机制中的作用进行综述,以期为ECRS的诊断和治疗提供理论参考。  相似文献   
2.
Granuloma annulare possibly triggered by antitetanus vaccination   总被引:4,自引:0,他引:4  
We report the case of a 6-year-old girl with granuloma annulare (GA) possibly related to antitetanus vaccinations. The first episode occurred 2 months after the girl had been vaccinated but the lesions were not located at the vaccination site. After 1 year of being free of lesions, she had a second episode unrelated to vaccination. After another 6-month lesion-free period, the girl was administered another antitetanus vaccination and a solitary lesion developed at the vaccination site within 3 days. A few lesions developed on her legs in the 2 months following the appearance of the initial plaque. The literature includes two reports of cases with papular lesions limited to the hepatitis B vaccination site, both histopathologically consistent with necrobiotic granuloma, but clinically not suggestive of GA. To the best of our knowledge, GA following antitetanus vaccination and occurring at the vaccination site has not been reported before. Either the trauma alone from the injection or a vaccine-induced immunological reaction might have triggered the necrobiosis of collagen through some unexplained mechanisms.  相似文献   
3.
We report the case of a 25-year-old male patient who presented with complaints of redness, photophobia, and decreased vision in the right eye of a week's duration. Slit-lamp biomicroscopic examination revealed a cream-colored, irregular elevated inferior iris mass, extending on to the anterior lens surface. Differential diagnoses of a fungal granuloma, a medulloepithelioma, and an amelanotic melanoma were considered. An excisional biopsy of the mass was performed through a superior clear corneal incision. Polymerase chain reaction analysis of the aqueous humor showed a positive pan fungal genome. Histopathology of the biopsied mass showed a giant cell granuloma with surrounding numerous branching, septate hyphae. Culture growth revealed Aspergillus fumigatus We report this case because of the rarity of Aspergillus iris granuloma as a primary presentation of endogenous Aspergillosis and review the relevant literature. Absence of a significant systemic history compounded the diagnostic dilemma in our patient. Definitive differentiation of this rare entity from a foreign body, amelanotic melanoma, and other inflammatory conditions such as sarcoidosis and tuberculosis, may be possible only on microbiological and histo-pathological evaluation.  相似文献   
4.
Deep granuloma annulare (DGA) is one of several lesions of skin and superficial soft tissues whose histologic character is a palisading granuloma with a small central focus of necrosis or necrobiosis. Unlike the other palisading necrobiotic lesions, DGA has a predilection for children in the first 5 to 6 years of life. A painless subcutaneous nodule(s) in the lower anterior tibial region or foot and the scalp, typically in the occiput, was the most common presenting feature in this study of 35 cases. Additional or recurrent lesions were reported in approximately 70% of cases with clinical follow-up. All lesions showed the presence of necrobiosis; however, one of the characteristic features was the multinodular character of the predominantly mononuclear cellular aggregates. The presence of vascular spaces at the periphery of the nodular profiles served as a clue to the diagnosis of DGA. The palisading arrangement of the mononuclear cells was evident only in those foci with central necrobiosis. A histiocytic disorder or fibrohistiocytic process was a common consideration in the differential diagnosis, especially in those cases with less apparent foci of necrosis. Palisading histiocytes with prominent eosinophilic cytoplasm and some nuclear atypism were problematic with regard to possible epithelioid sarcoma. Our study failed to identify any underlying or predisposing factors in the development of DGA. Despite the fact that DGA is a well-documented lesion in children, it occurs sufficiently infrequently that it is often not considered clinically when it presents as a subcutaneous mass or masses in a child. Its recognition by the pathologist is especially important as the occurrence of additional lesions in a high proportion of children can be anticipated without undue concern. Received June 16, 1997; accepted October 28, 1997.  相似文献   
5.
A 72-year-old fisherman who was positive for the HCV antibody developed an annular, erythematous, infiltrated lesions on sun-exposed areas. The lesions were diagnosed as annular elastolytic giant cell granuloma both clinically and histologically. Topical corticosteroid and cryotherapy with liquid nitrogen for several months failed to improve the lesions. We then started dapsone, a known anti-oxidant, at 50 mg/day. A month later, the margins of the erythematous lesions faded, and the infiltration gradually decreased. No recurrence has been observed for one year after the start of the therapy. Anti-oxidative therapy appears to be effective for annular elastolytic giant cell granuloma and could be an alternate therapy for refractory granulomatous disease.  相似文献   
6.
Schistosoma mansoni infection, both in humans and in animal models, is known to induce granulomas in the liver and intestine. It has also been reported that in humans the eggs of this parasite can reach the brain, causing psychiatric and neuropathological disorders. Whether this also occurs in rodents is unknown. To answer this question, mice were infected with this parasite and the central nervous system (CNS) examined at various time intervals. The results show that schistosomiasis induced granulomas in several regions of the CNS and increased nerve growth factor (NGF) levels in the cortex, hypothalamus and brain stem, but not in the hippocampus. The infection also caused paw hyperalgesia, as determined by the hot-plate test, and a local increase in NGF, but not in substance P. These findings indicate that the murine model of infection can be used for studying mechanisms leading to human neuroschistosomiasis and suggest that the neuropathological disorders and the sensory deficits observed in human schistosomiasis are associated with impaired levels of NGF in the peripheral and central nervous system. Received: 18 January 1996 / Revised, accepted: 16 April 1996  相似文献   
7.
Summary Sarcoidosis is a multisystem disease characterized by enhanced immune responses at sites of involvement. To elucidate the immunopathogenesis of ophthalmic lesions, cell infiltrates in biopsies from conjunctiva and other tissues involved (lungs, lymph nodes, skin) were studied in 26 patients with active sarcoidosis in order to define the surface phenotype and the distribution of cells in granulomatous lesions. Biopsy specimens were also stained for detection of immunoglobulins, complement and fibrinogen deposits. The data demonstrate a lymphocytes/macrophages interaction in the central core of granulomatous areas as the crucial event that initiates the maintains the state of inflammation: at all sites of disease activity is present a compartmentalization of T-cells expressing a helper-related phenotype which account for the great majority of infiltrating cells both in the early lesions (aggregate of macrophages surrounded by lymphocytic infiltrate) and in well-organized sarcoid granulomata. The presence of plasma cells and immunoglobulin deposits may represent an epiphenomenon in line with the helper infiltration, suggesting a local hyper-reactivity of the B-cells immune system. This study suggests some immunopathogenetic mechanisms leading to the formation and growth of conjunctival sarcoid granulomata.  相似文献   
8.
9.
本文首次报导了螨类接种豚鼠气管所引起的肺部病变。螨类接种后的第6天发现肺部已形成典型的结节性病灶。结节呈圆锥形,淡黄色,直径1~5mm之间。镜下主要表现为细支气管和细支气管周围的病变。和早年报导的猴肺螨病肺部病变比较,有以下不同,肺实质内有明显的异物肉芽肿形成,炎症反应中嗜酸性细胞浸润不明显,而有更多的异物巨细胞形成;细支气管周围的小动脉受到损害:部分小动脉壁平滑肌明显增厚,以致腔隙变窄,部分小动脉腔内可见到虫体。根据我们实验研究证明,螨类接种豚鼠气管可引起肺部的典型病变.因而认为用豚鼠作为肺螨病的动物模型是有希望的。  相似文献   
10.
Summary An unusual case of a woman with primary biliary cirrhosis and cutaneous sarcoidosis is described. The factors that allow a specific diagnosis of each condition are presented and the literature pertaining to such complex and unusual cases is presented.This work was supported in part by a grant from the Gastroenterology Medical Research Foundation of Southwestern Pennsylvania.  相似文献   
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