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51.
N-Hydroxy-2-acetylaminofluorene (N-OH-AAF) is the proximate carcinogenic metabolite of the powerful rat liver carcinogen 2-acetylaminofluorene. In this study, transgenic Big Blue(R) rats were used to examine the relationship between in vivo mutagenicity and DNA adduct formation by N-OH-AAF in the target liver compared with that in nontarget tissues. Male rats were given one, two, or four doses of 25 mg N-OH-AAF/kg body weight by i.p. injection at 4-day intervals, and groups of treated and control rats were euthanized up to 10 weeks after beginning the dosing. Mutant frequencies were measured in the spleen lymphocyte hprt gene, and lacI mutant frequencies were determined in the liver and spleen lymphocytes. At 6 weeks after beginning the dosing, the hprt mutant frequency in spleen lymphocytes from the four-dose group was 16.5 x 10(-6) compared with 3.2 x 10(-6) in control animals. Also at 6 weeks, rats given one, two, or four doses of N-OH-AAF had lacI mutant frequencies in the liver of 97.6, 155.6, and 406.8 x 10(-6), respectively, compared with a control frequency of 25.7 x 10(-6); rats given four doses had lacI mutant frequencies in spleen lymphocytes of 55.8 x 10(-6) compared with a control frequency of 20.4 x 10(-6). Additional rats were evaluated for DNA adduct formation in the liver, spleen lymphocytes, and bone marrow by (32)P-postlabeling. Adduct analysis was conducted 1 day after one, two, and four treatments with N-OH-AAF, 5 days after one treatment, and 9 days after two treatments. N-(Deoxyguanosin-8-yl)-2-aminofluorene was the major DNA adduct identified in all the tissues examined. Adduct concentrations increased with total dose to maximum values in samples taken 1 day after two doses, and remained essentially the same after four doses. In samples taken after four doses, adduct levels were 103, 28, and 7 fmol/microg of DNA in liver, spleen lymphocytes, and bone marrow, respectively. The results indicate that the extent of both DNA adduct formation and mutant induction correlates with the organ specificity for N-OH-AAF carcinogenesis in the rat. Environ. Mol. Mutagen. 37:195-202, 2001. Published 2001 Wiley-Liss, Inc.  相似文献   
52.
Inflammatory pseudotumors (IPTs) of the lymph node and spleen are an uncommon, benign cause of lymphadenopathy and/or splenomegaly that often bear striking clinicopathologic similarities to the inflammatory myofibroblastic tumors (IMTs) found in soft tissues. These tumors have classically been grouped together under the umbrella category of "inflammatory pseudotumor." Recent evidence shows that IMTs are in fact neoplastic processes that often harbor balanced chromosomal translocations involving the ALK kinase gene. These translocations result in expression of ALK kinase in IMTs as assessed by immunohistochemical studies. However, the relationship between IMT and IPT of the lymph node and spleen is uncertain. To determine if ALK tyrosine kinase expression is also present in IPT, 13 cases of IPT (9 involving lymph nodes, 4 splenic lesions) were examined for the presence of ALK tyrosine kinase by immunohistochemical staining on paraffin-embedded tissue. In addition, in situ hybridization studies for Epstein-Barr virus--encoded RNAs (EBER) and immunoperoxidase studies for human herpesvirus-8 (HHV8)--specific proteins were performed. All cases had clinical, morphologic, and immunophenotypic findings typical of IPT and had varying proportions of fibroblastic and inflammatory components. Age ranged from 11 to 75 (median, 40) years; 8 subjects were male, and 5 were female. None of the cases (0 of 13) had positive staining for ALK kinase or HHV8, and in 1 a lymph node (1 of 13) was focally positive for EBV (EBER) by in situ hybridization. The absence of ALK kinase as detected by immunohistochemical studies in IPT of the lymph node and spleen suggests that this entity is biologically distinct from the histologically similar IMT.  相似文献   
53.
A method is described for accurately determining the frequency of precursors of hapten specific cytotoxic T cells. The method is based on a standard Poisson analysis of limit dilution cultures, but makes a correction of 'anti-self' reacting clones and for spontaneously arising clones that recognise modified self. These corrections are shown to be especially important when low hapten densities are used, where there may be more than a 10-fold difference between the corrected and uncorrected frequency estimates. Determined levels of antigen specificity and of H-2 restriction are significantly enhanced by application of this method.  相似文献   
54.
An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts.  相似文献   
55.
目的探讨多器官功能障碍综合征(MODS)病程中脾脏树突状细胞(DC)变化对炎症因子的影响与作用。方法采用腹腔注射酵母多糖的方法复制小鼠MODS模型,分为正常对照组和MODS组。采用流式细胞技术检测脾脏DC免疫表型,运用免疫组化技术检测脾脏中促炎因子IL-1β与抗炎因子IL-10的表达,计量观察DC与炎症因子在病程中的变化并做相关分析。结果伤后6h组,脾脏中CD11c^+/MHC-Ⅱ’DC数目与IL-18’细胞数目均明显增多,至24h组达峰值。自48h组,CD11c^+/MHC-Ⅱ’DC与IL-1β’细胞含量开始下降,在6天组和10~12天组降至正常组或低于正常组含量;而同时CD11c^+/MHC-Ⅱ^-DC和IL-10阳性细胞含量则相对增多,至10~12天组阳性细胞含量显著升高达到峰值。结论DC的活性在MODS病程早期与IL-1β表达呈正相关性,在病程晚期与IL-10表达呈负相关,提示脾脏DC活性变化与促炎因子和抗炎因子均有密切的相关性。  相似文献   
56.
AIMS: Diffuse haemangiomatosis of the spleen is a rare benign vascular condition occurring as a manifestation of systemic angiomatosis or, less commonly, confined to the spleen. It is sometimes accompanied by severe disturbance of blood coagulation. The goal of this study was to characterize an additional case of isolated diffuse haemangiomatosis of the spleen and to determine the histogenesis of this lesion which remains obscure. METHODS AND RESULTS: We describe a case of isolated diffuse haemangiomatosis of the spleen in which histological and immunohistological findings suggested the possibility of a malformative tumour-like lesion. The pathological cavernous vessels were distributed randomly through the red pulp, without continuity with sinuses. The endothelial cells expressed vimentin, factor VIII related antigen and CD34, but not CD8. Some cells lining the sinus lumen expressed CD68, lysozyme and myeloperoxidase. In addition, trabecular veins presented with intimal thickening. These results allow making a diagnosis between diffuse haemangiomatosis and other tumours/tumour-like lesions of the spleen, especially littoral cell angioma, splenoma and peliosis. CONCLUSION: If diffuse haemangiomatosis is usually classified as a benign proliferation of endothelial cells, we suggest that diffuse haemangiomatosis, when confined to the spleen, could be a tumour-like vascular lesion. In this hypothesis, the aetiology may be hamartomatous or malformative as is suspected in arterio-venous haemangioma of the lower extremities. The histogenesis is still questionable and no definitive proof in favour of one or the other hypothesis has been reported.  相似文献   
57.
Cells bearing the form of the TCR make up only 1–3% ofT cells in the adult murine thymus and peripheral lymphold organs.Evidence from studies of nude mice suggests that the developmentof at least some T cells is thymus dependent; however, untilnow it has not been directly demonstrated that cells are exportedfrom the thymus. In this paper we have used the technique oflabelling thymocytes in vivo with FITC, followed by flow cytometrlcanalysis to trace cells emigrating from the thymus to the spleen.Using this approach we have been able to demonstrate for thefirst time that T cells are exported from the adult murinethymus to the spleen. We also demonstrate that the cells emigratingto the spleen are a selected subset of thymocytes being heatstable antigen positive, Thy-1+, and expressing low levels ofCD44 (Pgp-1). In addition, investigation of TCR V; gene usageamong adult + thymocytes, recent emigrants, and spleen cells,indicated a selective emigration of cells expressing certainVgenes.  相似文献   
58.
为探讨补肾健脾方药对卵巢切除大鼠骨密度、骨矿含量的影响,取10月龄SD雌性大鼠40只,随机分为模型组、正常对照组、E3阳性对照组、中药组,每组10只,正常对照组行假手术,其余3组行完整双侧卵巢除术。术后第3天开始灌胃给药,连续用药满12周后处死,分离L3腰椎体及左侧股骨,进行骨矿密度、骨矿含量、表观骨密度测定。结果显示补肾健脾方药能明显维持切除卵巢大鼠椎体及股骨的骨矿密度、骨矿含量和表观密度。  相似文献   
59.
慢性乙型肝炎病因病机探讨   总被引:10,自引:0,他引:10  
慢性乙型肝炎的病因与湿热疫毒密切相关,湿热毒邪是乙肝发生的始动因素,脾运不健是乙肝发生发展的内在基础,肝络瘀阻是病变发展的重要病理环节,肝肾亏扣则病变发展的必然结果,病机特点为正虚邪恋,本虚标实,致病热缠绵,病情反复波动,治疗上必须有的效矢,才能取得满意的效果。  相似文献   
60.
目的:通过应用中医传承辅助平台(V 2.5)挖掘中医药治疗小儿湿疹的组方用药规律,并对高频药物、用药模式及治疗思路进行探讨。方法:搜集国家知识基础设施数据库(CNKI)、中国学术期刊数据库(CSPD)及中文科技期刊数据库(CCD)中2000—2021年应用中医药治疗小儿湿疹的相关文献,经过筛选后建立方药数据库,运用中医传承辅助平台(V 2.5)集成的改进互信息法、关联规则Apriori算法、复杂系统熵聚类与无监督熵聚类等算法对药物频次、性味归经、用药模式、规则分析及新处方等结果进行输出,并进行网络可视化展示。结果:纳入处方200首,共涉及206味中药,高频药物包括甘草、白鲜皮、薏苡仁、茯苓、生地黄、金银花、蝉蜕、地肤子、防风、牡丹皮等,药性以寒性(52.76%)居多,药味以甘(38.89%)、苦(33.37%)、辛(21.96%)味为主,归经以胃经(1 138次)、脾经(1 088次)、肝经(1 061次)居多,并且得到药物之间的关联规则,以及新处方6个。结论:小儿湿疹用药以补虚药、利水渗湿药、清热药、清热解毒药、解表药为主,治疗以疏风清热,燥湿健脾,养血活血为主要大法,分析结果与本病诊疗指南较为吻合,可为小儿湿疹的临床治疗及新药开发提供参考。  相似文献   
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