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1.
J C Ho M Chan-Yeung S P Ho J C Mak M S Ip G C Ooi M P Wong K W Tsang W K Lam 《The European respiratory journal》2007,29(2):273-278
The present study aimed to determine the alterations of antioxidant activities in erythrocytes from patients with nonsmall cell lung carcinoma (NSCLC). A comparative study of the systemic antioxidant activities in red blood cell lysate from subjects with NSCLC and healthy control subjects was conducted. The antioxidants catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured using chemical kinetic reactions under spectrophotometry. In total, 189 cases of mostly advanced-stage IIIB or stage IV NSCLC and 202 healthy controls were studied. In subjects with lung cancer, there was similar catalase activity, lower SOD activity (median (interquartile range) 13.4 (9.0-27.2) versus 48.7 (27.0-64.3) U x (ghaemoglobulin(Hb)(-1)), and higher GPx activity (175.2 (126.6-288.3) versus 49.2 (39.5-59.2) mU x (gHb)(-1)) compared with controls. The antioxidant activities in lung cancer subjects were not associated with age, sex, smoking status, or tumour cell types. However, more advanced disease (stage IV compared with stage IIIB) was associated with lower SOD activity. Using multivariable analysis, the presence of lung cancer independently predicted SOD and GPx activities. In conclusion, nonsmall cell lung carcinoma in Chinese subjects is associated with alterations in systemic antioxidant activities, which may play an important role in carcinogenesis. 相似文献
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A 44-year-old female with Cushing's disease associated with a pituitary macroadenoma was treated with cyproheptadine, 24 mg per day, after partial surgical resection of the tumor. A large residual tumor remained. There was no clear suppression of serum and urinary cortisol during therapy, but both levels rose markedly to beyond pre cyproheptadine levels, on withdrawal of the drug. This is the first report on the use of cyproheptadine in Cushing's disease associated with a pituitary macroadenoma. The response in this patient indicates an influence of cyproheptadine on ACTH secretion by the macroadenoma. 相似文献
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目的 大量富集三裂叶蟛蜞菊倍半萜内酯A,B(WTA,WTB)。方法 采用气相色谱法测定WTA和WTB,并以WTA和WTB的含量、洗脱率、精制度为考察指标,研究D101大孔树脂吸附WTA和WTB的工艺条件及参数。结果 通过大孔树脂吸附后,WTA和WTB的洗脱率达90%,50%乙醇洗脱部分中WTA和WTB的含量为总固物的4.01%~4.09%。结论 可以采用大孔树脂富集WTA和WTB。 相似文献
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The proliferative activity of gastric cancer cells with endocrine features was evaluated in five cases by means of a double-immunostaining procedure. The endocrine cells were recognized by a monoclonal antibody to chromogranin A (CGA) and the proliferative activity by a monoclonal antibody to proliferating cell nuclear antigen (PCNA). With the use of two different chromogens it was easy to determine whether CGA was located in the cytoplasm and whether PCNA was located in the nucleus of the same section. The CGA-positive endocrine cells of the normal gastric antral mucosa could be readily distinguished from the PCNA-positive cells scattered in the mucosal neck zones. Over 1,000 CGA-positive cancer cells were counted per case. A few cells (average, less than 1.0%) exhibited faint nuclear staining with anti-PCNA; in no instance was unequivocal PCNA reactivity demonstrable in the gastric cancer cells with endocrine differentiation. By contrast, the PCNA reaction was positive in one fourth to one third of the other cancer cells. These observations suggest that gastric cancer cells with endocrine features are differentiated and do not participate in the cell cycle. 相似文献
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