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991.
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Cooperative role of telomerase activity and p16 expression in the prognosis of non-small-cell lung cancer. 总被引:4,自引:0,他引:4
Rosa González-Quevedo Pilar Iniesta Alberto Morán Carmen de Juan Andrés Sánchez-Pernaute C Fernández Antonio Torres E Díaz-Rubio Jose-Luis Balibrea Manuel Benito 《Journal of clinical oncology》2002,20(1):254-262
PURPOSE: Telomerase activity and p16 expression can be considered two of the most important molecular markers implicated in tumorigenesis. Our main aim was to study the cooperative role of both molecular alterations in the prognosis of patients surgically resected for non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: We have determined telomerase activity and p16 expression in a series of 98 prospectively collected NSCLC specimens obtained from patients who had undergone surgery without other treatment. Telomerase activity was investigated by a telomeric repeat amplification protocol enzyme-linked immunosorbent assay-based procedure, and p16 expression was examined by Western blot. Associations with survival were evaluated. RESULTS: Positive results for telomerase activity were found in 82% of the cases, and this variable correlated with poor differentiation and recurrence of tumors. Lack of p16 expression was observed in 61% of tumors, and a significant association with tumor recurrence was also observed. By univariate analysis, both negative telomerase activity and p16-positive expression were significantly correlated with a better prognosis. Moreover, statistics for equality of survival distributions for telomerase, adjusted for p16, indicated a positive interaction between both parameters. For telomerase-positive tumors, p16 expression emerged as a significant independent protective variable, as indicated by Cox multivariate analysis (relative risk [RR], 0.214; P =.014). This protective effect was maintained only for stage I and II tumors (RR, 0.108; P =.046). CONCLUSION: These results suggest that the combined telomerase activity and p16 expression analyses may be of prognostic importance in NSCLC, especially for patients affected by stage I and II tumors. 相似文献
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Diana González-Espinosa Miguel A. Jiménez Ríos Andrés A. Gutiérrez-López 《Clinical & translational oncology》2002,4(5):241-249
The recombinant DNA technology has been an invaluable tool for understanding the mechanisms of carcinogenesis. For example, we have been able to know that in our own genome there are genes with the capacity to induce transformation (oncogenes) or with the capacity to block it (tumor suppresor genes). This technology has also helped to develop new strategies for the diagnosis and treatment of cancer. Unfortunately none of the genetic changes described to date for prostate cancer (CaP), has been accepted as a universal molecular marker for clinical use. On the other hand the restitution, blockade or the acquisition of certain genetic activities have been used to control local or locally advanced CaP, by means of gene therapy. The toxicity generated by the viral vectors used in the first gene therapy-clinical trials (phases I/II) has been moderate and the results encouraging. For these reasons, gene therapy could be used as an adjuvant treatment for the management of these cases in the near future. 相似文献
994.
Jensen E Sandström K Andréasson S Nilsson K Berggren H Larsson LE 《Paediatric anaesthesia》2000,10(3):297-302
The aim of this study was to evaluate changes in concentrations of the neurospecific protein S-100 in relation to cardiac surgery with cardiopulmonary bypass (CPB) and noncardiac general surgery in children below 3 years of age. Seventeen children underwent surgery for congenital heart disease and all survived without clinical signs of neurological complications. Samples for plasma concentrations of S-100 in these patients were taken on three occasions in connection with surgery: before the start of surgery, after CPB and finally 16-20 h after CPB. In the noncardiac group of 31 children, S-100 concentrations were measured on two occasions: before surgery and during surgery. In both groups, a significant increase in S-100 concentrations was observed during surgery, although the increase in the CPB group was significantly higher than in the noncardiac group. The CPB group included four children with Down's syndrome who had higher mean S-100 concentrations on all sampling occasions compared to the remaining patients. The peak S-100 concentrations after cardiac surgery were related to the duration of CPB, the time from the termination of CPB to the first post-CPB sample, as well as mean arterial pressure and cerebral arteriovenous lactate difference during rewarming. All the children studied (Down's patients excluded) had age-dependent plasma concentrations of S-100 measured before surgery. It can be concluded that CPB initiates a marked but transient release of S-100 into the systemic circulation during open heart surgery in children who are not developing clinical signs of neurological sequelae. 相似文献
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Andréa D Bertoldi Aluísio JD Barros Anita Wagner Dennis Ross-Degnan Pedro C Hallal 《BMC health services research》2008,8(1):222
Background
Studies carried out in the community enable researchers to understand access to medicines, affordability, and barriers to use from the consumer's point of view, and may stimulate the development of adequate medicines policies. The aim of the present article was to describe methodological and analytical aspects of quantitative studies on medicine utilization carried out at the household level. 相似文献999.