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51.
Cell proliferation of 174 specimens obtained from the primary gastric cancers using endoscopic biopsy was investigated by immunohistochemical analysis with the monoclonal antibody PC10, which recognizes a proliferating cell nuclear antigen (PCNA) in formalin-fixed and paraffin-embedded material. All the examined samples showed nuclear staining for PCNA in cancer cells. The investigation was to test the correlation between PCNA labeling and lymph node metastasis. DNA aneuploidy was often encountered in tumors with nodal involvement and lymphatic invasion. The logistic regression analysis identified PCNA labeling rates (LRs), tumor size, and macroscopic type as independent significant factors for lymph node metastasis. When the PCNA LRs and clinicopathologic parameters were entered into the Cox regression analysis, PCNA LRs and DNA ploidy emerged as independent significant prognostic factors. In addition, combination assay of PCNA LRs and DNA ploidy yielded a powerful prognostic indication for patients with gastric cancer. 相似文献
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AJ Ferreira WP Elias JS Pelayo R Giraldi MZ Pedroso IC Scaletsky 《Canadian Metallurgical Quarterly》1997,19(4):285-288
In the present study, in order to get a better insight into the mechanism of action of cyclophosphamide (CY) in rheumatoid arthritis (RA), we monitored the changes in lymphocytes' expression of leukocyte function associated antigen 1 (LFA-1). A group of 28 patients with refractory severe RA were treated with CY and methylprednisolone (MO) intravenously. Using flow cytometry we evaluated the changes in LFA-1 molecule expression on peripheral lymphocytes. In the analyzed group of patients the proportion of LFA-1 "dim" cells was reduced. After the treatment the ratio was partly normalized. Twelve months after cessation of the therapy high proportion of LFA-1 "dim" was observed only among CY/MP treated patients. The changes were related to clinical improvement. Based on the obtained data, it seems, that the treatment affecting the expression of LFA-1 may slow down lymphocyte migration and by that limit chronic inflammation within the synovium. 相似文献
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BACKGROUND: It has been suggested that tumors respond differently after irradiation with 10 or more fractions than with less fractionated regimens and that extrapolation from experiments with only a few fractions to "curative" regimens may be invalid. To test this hypothesis, we compared hypofractionated-accelerated treatments with "curative" fractionation schedules in human squamous cell carcinoma in nude mice. MATERIAL AND METHODS: FaDu tumors were transplanted subcutaneously into the hindleg of NMRI nu/nu mice. TCD50 values, i.e., the dose necessary to control 50% of the tumors locally, were determined after irradiation under ambient blood flow conditions with 5 and 10 fractions in 5 days, 10 fractions in 10 days, and 30 fractions in 15 days, 6 weeks or 10 weeks. RESULTS: TCD50 values of the hypofractionated regimens were not significantly different and varied from 41 to 46 Gy. The number of fractions given in the same overall time had no measurable effect on local tumor control. The TCD50 after 30 fractions in 6 weeks was 30 Gy higher than after the hypofractionated regimens. This effect was caused by a substantial increase of TCD50 with overall treatment time, the dose recovered per day was 0.82 Gy (95% CI 0.66; 0.96). alpha/beta eff determined from all data was 58 Gy (13; infinite). CONCLUSIONS: The results of the present study compare well with our previous findings after different "curative" fractionation schedules in the same tumor. Thus, our study does not support that tumors respond differently after application of 10 or more fractions compared to less fractionated regimens. The biological mechanisms that govern the radiation response of FaDu tumors appear to be the same for hypofractionated-accelerated and "curative" regimens. Since only one tumor was investigated, these results cannot be generalized at the present time. 相似文献
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WP Su 《Canadian Metallurgical Quarterly》1987,35(17):9245-9246
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