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41.
目的:研究PTEN抑癌基因在乳腺癌组织中的表达,探讨其与乳腺癌病人的外周血、骨髓及前哨淋巴结微小转移灶之间的关系。方法:选择53例乳腺癌病人的组织标本,用免疫组织化学方法检测原发肿瘤PTEN蛋白的表达;用定量RT鄄PCR法测定原发肿瘤PTENmRNA的表达。以免疫细胞化学法检测外周血和骨髓中的微小转移灶;HE染色和免疫组织化学法检测前哨淋巴结中的微小转移灶。结果:外周血、骨髓及前哨淋巴结中微小转移灶的检出率分别是24.5%,56.6%,26.4%和41.5%。乳腺癌组织中PTEN蛋白表达呈丢失者占35.8%,后者与外周血和骨髓微小转移灶间无显著关系,而与前哨淋巴结中的微小转移密切相关(P≤0.001)。PTENmRNA的表达与外周血、骨髓及前哨淋巴结中的微小转移灶之间均无显著相关性。结论:乳腺癌组织中PTEN蛋白表达的丢失与前哨淋巴结中的微小转移有密切关系,可作为预测其早期转移的重要指标。  相似文献   
42.
To study the activation of T lymphocytes in hyperthyroid Graves' disease, the serum concentrations of soluble interleukin 2 receptors (sIL2R) were determined during active thyrotoxicosis and following the return to a euthyroid state with carbimazole therapy. Serum sIL2R was measured by an enzyme linked immunoassay. The mean +/- SD serum sIL2R concentration during untreated hyperthyroidism was elevated as compared with controls (919.1 +/- 523.4 vs 374.2 +/- 189.4 U/ml, P less than 0.005). However, after carbimazole therapy the serum sIL2R in euthyroid patients fell to 377.9 +/- 90.3 U/ml, which did not differ from healthy controls. Serum sIL2R correlated significantly with the serum free T3 only during hyperthyroidism (r = 0.678, P less than 0.01). Our study suggests that in vivo measurement of serum sIL2R released from activated T lymphocytes is a useful immunological indicator of disease activity.  相似文献   
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A patient is described who has recurrent pericardial effusion and in whom a pericardial window created by balloon dilatation was directly identified by echocardiography. Echocardiography represents an additional useful means for confirming the immediate success of the procedure.
pericardial effusion, balloon dilatation, echocardiography  相似文献   
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We report a patient with a disease characterized by proliferation of T cells with Fc receptors for IgG (TG). However, unlike lymphoid cells from normal individuals or from patients with other lymphoid malignancies, the patient's lymphocytes spontaneously produced gamma interferon (IFN-gamma) in vitro. The peripheral lymphocytes consisted of 95% TG cells, which exhibited the morphological characteristics of T- cell chronic lymphocytic leukemia (CLL) and were normal on cytochemical and chromosome analysis. The majority of TG cells were OKT3+, OKT8+, and OKT4-, 3A1-. These cells failed to express suppressor cell activity and displayed depressed levels of natural killer activity, but mediated antibody-dependent cell-mediated cytotoxicity. The spontaneous production of IFN-gamma by human peripheral lymphoid cells as demonstrated in this study may serve as a probe for studying the relationship between IFN-gamma and the proliferation of human T-cell subsets.  相似文献   
47.
Blastomyces dermatitidis is a dimorphic fungus endemic to northwestern Ontario, Manitoba and some parts of the United States. The fungus is also endemic to parts of Africa. Pulmonary and extrapulmonary findings of a 24-year-old African man who presented with weight loss, dry cough and chronic pneumonia not resolving with antibiotic treatment are presented. The unusual occurrence of pulmonary blastomycosis associated with skin lesions and a moderate pleural effusion is reported.  相似文献   
48.
淋巴丝虫病为东南亚、西太平洋及南太平洋的重要公共卫生问题。此为慢性病,丝虫之成虫寄生于淋巴管或淋巴结,长达10-18年之久,致淋巴循环受阻塞而形成象皮病。根据微丝蚴在人体末梢血液之出现时间,分为日间和夜间之周期型与亚周期型。媒介多达40余种。防治方法主要赖药物治疗,世界卫生组织预期以现有的药物可于2020年消灭全球之淋巴丝虫病。本将班氏丝虫、马未丝虫及旁汶丝虫发现之经过,微丝蚴定期性,病媒蚊种及防治原则,作了相当完整的综述。笔曾在中所提及的多数国家实地防治丝虫病。  相似文献   
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DNA methyltransferase (MTase) activity in nuclear extracts from neoplastic and preneoplastic livers of rats fed a methyl-deficient diet (MDD) is elevated compared with that seen in the livers of control rats. Nuclear proteins were prepared in the presence of protease inhibitors including trans-epoxy succinyl-L-leucylamido-(4- guanido)butane and were fractionated by isoelectric focusing. In normal, control liver, two distinct MTase fractions were observed. In MDD-induced malignant liver, a third fraction, in addition to the previous two, was also seen. Both the DNA substrate and the cytosine site specificities of the third MTase fraction differ from those of the other two fractions. The distinct MTase activity in liver tumor has significantly more de novo MTase activity than do the MTase fractions of normal, control liver. Thus, normal and neoplastic rat livers differ in DNA MTase fractionation patterns and site specificities. The altered DNA MTase activity observed in rat liver tumors caused by MDDs may be one of the critical factors contributing to cancer formation through abnormal DNA methylation.   相似文献   
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