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21.
A nuclear protein associated with human cancer cells binds preferentially to a human repetitive DNA sequence. 总被引:2,自引:1,他引:1 下载免费PDF全文
M L Law J Z Gao T T Puck 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(21):8472-8476
A protein (Rp66) of 66 kDa was shown by DNA-binding protein blot assay to bind to a human repetitive DNA sequence (low-repeat sequence; LRS) in each of 10 transformed human cell lines examined. This protein-DNA interaction was not observed in 11 normal human cell cultures or in the Chinese hamster cell line CHO-K1. Gel retardation assay confirmed the specificity of the protein-DNA binding between Rp66 and LRS. In a histiocytic lymphoma human cell line, U937, that can be induced to differentiate in the presence of phorbol ester, this binding disappeared after cell differentiation. These together with other results cited suggest a regulatory role for these repetitive sequences in the human genome, with particular application to cancer. 相似文献
22.
Expression of Anion Exchanger 1 Sequestrates p16 in the Cytoplasm in Gastric and Colonic Adenocarcinoma 下载免费PDF全文
Wei-Wei Shen Jun Wu Li Cai Bing-Ya Liu Yan Gao Guo-Qiang Chen Guo-Hui Fu 《Neoplasia (New York, N.Y.)》2007,9(10):812-819
p16INK4A (p16) binds to cyclin-dependent kinase 4/6 and negatively regulates cell growth. Recent studies have led to an understanding of additional biologic functions for p16; however, the detailed mechanisms involved are still elusive. In this article, we show an unexpected expression of anion exchanger 1 (AE1) in the cytoplasm in poorly and moderately differentiated gastric and colonic adenocarcinoma cells and in its interaction with p16, thereby sequestrating the protein in the cytoplasm. Genetic alterations of p16 and AE1 were not detectable. Forced expression of AE1 in these cells sequestrated more p16 in the cytoplasm, whereas small interfering RNA-mediated silencing of AE1 in the cells induced the release of p16 from the cytoplasm to the nucleus, leading to cell death and growth inhibition of tumor cells. By analyzing tissue samples obtained from patients with gastric and colonic cancers, we found that 83.33% of gastric cancers and 56.52% of colonic cancers coexpressed AE1 and p16 in the cytoplasm. We conclude that AE1 plays a crucial role in the pathogenesis of gastric and colonic adenocarcinoma and that p16 dysfunction is a novel pathway of carcinogenesis. 相似文献
23.
和谐是发展的条件,和谐产生动力。如何利用和谐因素消除不和谐因素,是中医发展值得重视和研究的问题。对中医发展中的和谐方面进行了探讨。 相似文献
24.
利福喷汀治疗耐利福平肺结核的疗效分析 总被引:1,自引:0,他引:1
目的分析增加利福喷汀的用药剂量对利福平耐药肺结核的疗效,以评价利福喷汀在治疗利福平耐药患者中的作用。方法根据药敏结果选取耐利福平肺结核患者101例,分为治疗1组(利福平低耐),治疗2组(利福平高耐),两组治疗方案中均含利福喷汀,对照组(利福平高耐)治疗方案中不合利福喷汀。观察治疗后3、18个月疗效。结果治疗1组在各阶段的痰菌阴转率、病灶吸收和空洞闭和情况明显优于治疗2组和对照组,两组差异有统计学意义;治疗2组的痰菌阴转率、病灶吸收和空洞闭和情况略优于对照组,两者差异无统计学意义。结论对利福平耐药的患者尤其在利福平低度耐药病例中,可以选择增加利福喷汀用药剂量的方案进行治疗,在利福平高度耐药病例中利福喷汀的作用不能确定。 相似文献
25.
Gerard J Molloy Derek W Johnston Chuan Gao Miles D Witham Joan M Gray Ishbel S Argo Allan D Struthers Marion E T McMurdo 《European journal of cardiovascular prevention and rehabilitation》2006,13(3):381-387
BACKGROUND: The impact of exercise programmes for heart failure on those close to the patient is largely unknown. We examined the effect of a hospital and home-based exercise intervention on burden, anxiety and depression of informal caregivers. DESIGN: The study was a randomized, controlled trial. Heart failure patients were randomized to a seated 12-week hospital-based exercise programme. Caregiver measures were gathered at baseline, 3 months later and 6 months following baseline. METHODS: Sixty caregivers (mean age 63.4 years, 65% female) of heart failure patients (n = 82, mean age 80.5 years, 44% female) participating in a trial of an exercise intervention were recruited. Caregiver burden, anxiety and depression were assessed. RESULTS: There were no differences in caregiver burden, depression or anxiety between the two groups of caregivers at baseline (caregiver burden, patient control 33.1 versus patient exercise 34.1; anxiety 4.1 versus 5.5; depression 2.8 versus 3.8). At 3 months there were no differences between caregivers in the two groups on outcomes. At 6-month follow-up caregivers of heart failure patients in the exercise group had burden scores that were significantly worse than the control group. There were no differences between the carers of exercise and control groups in anxiety and depression. Levels of anxiety and depression in the entire carer sample were marginally higher than reference values in a healthy non-clinical sample. CONCLUSION: The present exercise interventions for frail older patients did not benefit caregivers and was associated with an increase in caregiver burden. We suggest that future exercise interventions for heart failure patients should actively incorporate informal caregivers into research designs. 相似文献
26.
[目的]探讨颅脑损伤病人应用亚低温治疗仪时具体间隔多长时间翻身不发生压疮.[方法]随机选择45例颅脑损伤应用亚低温治疗的病人,采取3 h后开始翻身,侧卧位时每次均为1 h,以后平卧位时间每次逐渐递增1/2 h.[结果]在应用亚低温治疗期间除3例病人在不同时段内发生轻微紫色冻伤外,所有病例均未发生压疮,平均翻身间隔时间为11.31 h,应用单样本统计学处理,有统计学意义(t=8.867,P<0.005).[结论]颅脑损伤病人在使用亚低温治疗过程中翻身间隔时间可以延长至8 h不发生压疮. 相似文献
27.
Advanced age has been associated with a wide range of defects in both the innate and adaptive immune systems including diminished specific antibody responses that increase the risk of invasive pneumococcal disease (IPD) and limit the effectiveness of vaccines. However, the elderly are a heterogeneous group and measures of overall frailty may be a better indicator of disease susceptibility (or vaccine response) than chronological age alone. 相似文献
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