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991.
Menéndez López V Molina Porto R Alcaraz Asensio A Gutiérrez del Pozo R Alcover García JA 《Actas urologicas espa?olas》2000,24(7):530-535
Contribution of 60 patients with primary surface transitional cell tumours of the bladder where nuclear expression of p53 protein was prospectively studied and compared to known prognostic factors in an attempt to find out its role in the development of relapses. An statistically significant relationship was found between the protein expression and cytology, tumoral multifocality, stage, relapse development and tumoral progression. It can be concluded that expression of this protein can be of use as relapse predictor. 相似文献
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de Diego Rodríguez E del Valle Schaan JI Gutiérrez Baños JL Martín García B Hernández Rodríguez R Portillo Martín JA Correas Gómez MA Roca Edreira A Villanueva Peña A Rado Velázquez MA Hernández Rodríguez A 《Actas urologicas espa?olas》2000,24(10):836-839
Prostatic carcinoma may be diagnosed by the clinic manifestations or by the symptoms for locoregional disemination and distance metastasis. The lymphatic system is the first metastatic station, which is affected in a high percentage of cases. Event it may simulate lymphoproliferatives process and it si uncommon the lymphatic macroaffectation at first. In theses cases, the histologic and immunohistochemical study by the determination of prostatic specific antigen in lymph nodes can provice the diagnosis. Treatment of these tumors is palliative with hormonotherapy. Prognosis is bad with a low survival at five years. 相似文献
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Incomplete DJH rearrangements as a novel tumor target for minimal residual disease quantitation in multiple myeloma using real-time PCR. 总被引:3,自引:0,他引:3
D González M González M E Alonso R López-Pérez A Balanzategui M C Chillón M Silva R García-Sanz J F San Miguel 《Leukemia》2003,17(6):1051-1057
The hypervariable regions of immunoglobulin heavy-chain (IgH) rearrangements provide a specific tumor marker in multiple myeloma (MM). Recently, real-time PCR assays have been developed in order to quantify the number of tumor cells after treatment. However, these strategies are hampered by the presence of somatic hypermutation (SH) in VDJH rearrangements from multiple myeloma (MM) patients, which causes mismatches between primers and/or probes and the target, leading to a nonaccurate quantification of tumor cells. Our group has recently described a 60% incidence of incomplete DJH rearrangements in MM patients, with no or very low rates of SH. In this study, we compare the efficiency of a real-time PCR approach for the analysis of both complete and incomplete IgH rearrangements in eight MM patients using only three JH consensus probes. We were able to design an allele-specific oligonucleotide for both the complete and incomplete rearrangement in all patients. DJH rearrangements fulfilled the criteria of effectiveness for real-time PCR in all samples (ie no unspecific amplification, detection of less than 10 tumor cells within 10(5) polyclonal background and correlation coefficients of standard curves higher than 0.98). By contrast, only three out of eight VDJH rearrangements fulfilled these criteria. Further analyses showed that the remaining five VDJH rearrangements carried three or more somatic mutations in the probe and primer sites, leading to a dramatic decrease in the melting temperature. These results support the use of incomplete DJH rearrangements instead of complete somatically mutated VDJH rearrangements for investigation of minimal residual disease in multiple myeloma. 相似文献
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Feliciano García-Vicente Angel Mi?ambres Inmaculada Jerez Ignaci Modolell Leopoldo Pérez Juan Jose Torres 《Radiotherapy and oncology》2003,67(2):239-249
BACKGROUND AND PURPOSE: Modern conformal radiotherapy treatments require accurate dose calculation in any relevant clinical situation. One of these situations is the treatment of lung tumors, where irradiation has to be planned under challenging conditions for dose calculation. In this study we assess the errors in dose values predicted by fast Fourier transform convolution (FFTC) and multigrid superposition (MGS) algorithms implemented in a commercial treatment planning system (TPS). MATERIALS AND METHODS: FFTC and MGS algorithms were used in a FOCUS 3.0.0 (Computerized Medical Systems, USA) to calculate doses in treatment plans using photon beams of 6 and 25 MV nominal energy from a Saturne 43 linac (GE Medical Systems, USA). A 10x10-cm beam irradiating a mediastinum-lung and a thoracic wall-lung-thoracic wall modeled geometry was assessed. The calculated data were compared with measurements performed with radiographic films and ionization chamber. RESULTS: FFTC algorithm leads to an average deviation from ionometric dose measurements of over 10%. Discrepancies between measured and calculated beam fringe values (distance between 50 and 90% isodose lines) of up to 8 mm were observed. For MGS algorithm, all the points assessed in both geometries fulfilled the 3%-3 mm accuracy criteria and the average deviation of absolute dose was about 1%. A maximum of 3 mm deviation in the beam fringe for any depth was found and was within 2 mm beyond the buildup region. Deviations between ionometric and film measurements were within 3%. CONCLUSIONS: MGS algorithm assesses with reasonable accuracy dose distributions and absolute dose in inhomogeneous regions like the lung region. Therefore, and respecting the inhomogeneity dose calculation, the system could be used in routine clinical practice and in dose-escalation programs. This is not true in the case of FFTC algorithm which leads to errors greater than 10% in the absolute dose calculation and underestimates the beam fringe by up to 8 mm. 相似文献
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