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21.
PURPOSE: To evaluate the effect of conventional and standard (ST) versus pulse-intensive (PI) chemotherapy and short-duration versus long-duration chemotherapy on relapse-free survival (RFS) and overall survival rates of patients with clear-cell sarcoma of the kidney (CCSK) entered onto the National Wilms' Tumor Study (NWTS)-4. PATIENTS AND METHODS: The 5-year and 8-year RFS rates were determined for patients with CCSK treated on the NWTS-4. After August 6, 1986, 40 previously untreated children younger than 16 years with CCSK were randomly assigned, after the completion of 6 months of chemotherapy, to discontinue (short) or continue 9 additional months (long) of treatment with chemotherapy regimens that included vincristine and either divided-dose (ST) courses (5 days) or single-dose (PI) treatment with dactinomycin and divided-dose (ST) courses (3 days) or single-dose (PI) treatment with doxorubicin. RESULTS: For patients with CCSK, the 5- and 8-year RFS rates were 65.2% and 60.6%, respectively, for patients randomly assigned to the short chemotherapy and 87.8% (both 5- and 8-year RFS) for patients randomly assigned to the long chemotherapy (P =.08). The overall survival rates for patients at 5 and 8 years were 95.5% and 85.9%, respectively, for the short chemotherapy and 87.5% (both 5- and 8-year overall survival) for the long chemotherapy (P =.99). In NWTS-4, the overall survival rates for patients with CCSK improved from NWTS-3 (83% v 66.9% at 8 years, respectively; P <.01). CONCLUSION: CCSK patients exhibit an improved RFS from a longer course of therapy when using vincristine, doxorubicin, and dactinomycin, but their long-term survival is unchanged compared with patients receiving 6 months of therapy. The overall survival rates for patients with CCSK have improved from NWTS-3.  相似文献   
22.
PURPOSE: On the basis of cytomorphology according to the French-American-British (FAB) classification, we evaluated the prognostic impact of dysplastic features and other parameters in de novo acute myeloid leukemia (AML). We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification. PATIENTS AND METHODS: We analyzed prospectively 614 patients with de novo AML, all of whom were diagnosed by central morphologic analysis and treated within the German AML Cooperative Group (AMLCG)-92 or the AMLCG-acute promyalocytic leukemia study. RESULTS: Patients with AML M3, M3v, or M4eo demonstrated a better outcome compared with all other FAB subtypes (P <.001); no prognostic difference was observed among other FAB subtypes. The presence or absence of dysplasia failed to demonstrate prognostic relevance. Other prognostic markers, such as age, cytogenetics, presence of Auer rods, and lactate dehydrogenase (LDH) level at diagnosis, all showed significant impact on overall and event-free survival in univariate analyses (P <.001 for all parameters tested). However, in a multivariate analysis, only cytogenetics (unfavorable or favorable), age, and high LDH maintained their prognostic impact. Dysplasia was not found to be an independent prognostic parameter, but the detection of trilineage dysplasia correlated with unfavorable cytogenetics. CONCLUSION: Our results indicate that cytomorphology and classification according to FAB criteria are still necessary for the diagnosis of AML but have no relevance for prognosis in addition to cytogenetics. Our results suggest that the WHO classification should be further developed by using cytogenetics as the main determinant of biology. Dysplastic features, in particular, have no additional impact on predicting prognosis when cytogenetics are taken into account.  相似文献   
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The international prognostic scoring system (IPSS) is considered the gold standard for risk assessment in primary myelodysplastic syndromes (MDS). This score includes several prognostic factors except serum lactate dehydrogenase (LDH). We evaluated the prognostic power of LDH as an additional variable in IPSS-based risk assessment. For this purpose, a total of 892 patients with primary MDS registered by the Austrian-German cooperative MDS study group was analyzed retrospectively. Multivariate analysis confirmed the value of established parameters such as medullary blasts, karyotype and peripheral cell counts and showed that elevated LDH was associated with decreased overall survival (P<0.00005) and increased risk of AML development (P<0.00005), independent of the system used to classify MDS (FAB or WHO). Moreover, elevated LDH was found to be a significant predictor of poor survival within each IPSS risk group and within each FAB group except RAEB-T. To exploit these results for refined prognostication, each IPSS risk group was split into two separate categories (A=normal LDH vs B=elevated LDH). Using this LDH-assisted approach, it was possible to identify MDS patients with unfavorable prognosis within the low and intermediate IPSS risk groups. We propose that the IPSS+LDH score should improve clinical decision-making and facilitate proper risk stratification in clinical trials.  相似文献   
25.
Latent and productive viral infections are at the extremes of the spectrum of virus-cell interactions that are thought to play a major role in the ability of such important human pathogens as human immunodeficiency virus (HIV) to elude host defenses and cause disease. The recent development of PCR-based methods to amplify target sequences in individual cells in routinely fixed tissues affords opportunities to directly examine the subtle and covert virus-cell relationships at the latent end of the spectrum that are inaccessible to analysis by conventional in situ hybridization techniques. We have now used PCR in situ with in situ hybridization to document latent and permissive HIV infection in routinely fixed and paraffin-embedded tissue. In one of the first specimens we examined, a tumor biopsy from an HIV-infected individual, we found many of the lymphocytes and lymphocytes infiltrating the tumor had HIV DNA that was detectable only by PCR in situ. The fraction of positive cells varied regionally, but there were foci where most of the cells contained HIV DNA. Most of these lymphocytes and macrophages are latently infected, as we could detect HIV RNA in fewer than one in a thousand of these cells. We also detected HIV RNA, surprisingly, in 6% of the tumor cells, where the number of copies of viral RNA per cell was equivalent to productively infected cell lines. The alternative states of HIV-gene expression and high local concentration of latently infected lymphocytes and monocytes revealed by these studies conceptually supports models of lentiviral pathogenesis that attribute persistence to the reservoir of latently infected cells and disease to the consequences of viral-gene expression in this population. The magnitude of infection of lymphocytes documented in this report is also consistent with the emerging view that HIV infection per se could contribute substantially to depletion of immune cells in AIDS.  相似文献   
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 We report on a patient with Fanconi's anemia (FA) who developed a myelodysplastic syndrome (RAEB-T) with complex karyotypic abnormalities (trp 1q23 q 42, monosomy 20, trisomy 13) at the age of 28. The patient achieved a complete hematological and cytogenetic remission after treatment with sequential high-dose cytosine arabinoside/mitoxantrone followed by G-CSF (5 μg/kg). Bone marrow hypoplasia was prolonged with 38 days of granulocytopenia <500/μl and 62 days of platelet transfusion dependency. Nonhematological toxicity did not exceed that of patients without underlying FA. Remission duration was 7 months. This observation shows the feasibility of high-dose Ara C treatment in patients with FA and MDS. Although hematopoiesis remained clonal in remission, the suppression of the cytogenetically abnormal clones transiently reversed the antecedent long-lasting pancytopenia. Received: 16 September 1996 / Accepted: 27 January 1997  相似文献   
28.
The reliability of quantitative coronary angiography (QCA) measurements is of fundamental importance for the study and practice of interventional cardiology. In vivo validation results have consistently reported a tendency for QCA systems to overestimate small luminal diameters. Such a systematic error may result in the underestimation of luminal gain during intracoronary procedures and in the underestimation of progression of coronary artery disease during longitudinal studies. We report the in vivo validation results of an experimental adaptive edge-detection algorithm that was developed to reduce overestimation of small luminal diameters by incorporating a dynamic function of variable kernel size of the derivative operator and variable weighting of the first and second derivatives of the brightness profile. The results of the experimental algorithm were compared to those of the conventional parent edge detection algorithm with fixed parameters. Dynamic adjustment of the edge-detection algorithm parameters was found to improve measurements of small (lt;0.8-mm) luminal diameters as evidenced by an intercept of +.07 mm for the algorithm with variable weighting compared to +0.21 mm for the parent algorithm with fixed weighting. A slope of <1 was found for both the parent and experimental algorithms with subsequent underestimation of large luminal diameters. Systematic errors in a QCA system can be identified and corrected by the execution of objective in vivo validation studies and the consequent refinement of edge-detection algorithms. The overestimation of small luminal diameters may be overcome by the incorporation of a dynamic edge-detection algorithm. Further refinements in edge-detection algorithms will be required to address the issue of underestimation of large luminal diameters before the absolute values derived from QCA measurements can be considered accurate over the full range of clinically encountered luminal diameters. © 1995 Wiley-Liss, Inc.  相似文献   
29.
In a 8 week double-blind randomized multicenter trial in 159 patients with benign gastric ulcer the efficacy of hydrotalcite vs. ranitidine in expediting ulcer healing and in achieving pain relief was determined. 79 patients received hydrotalcite 1000 mg q.i.d. as tablets equalling a total neutralizing capacity of 111.2 mval and 80 patients received ranitidine (300 mg at night). Endoscopically controlled healing rates after 4 weeks of therapy amounted to 41.8% with hydrotalcite and 53.8% with ranitidine. After 8 weeks both regimen showed significant equivalent healing rates (hydrotalcite: 81.0%, ranitidine: 78.8%, p < 0.003). Ulcer pain decreased parallel in both groups. By the end of therapy 92.4% of the patients treated with hydrotalcite and 86.3% of those receiving ranitidine were free of pain. Incidence of helicobacter pylori in antral mucosal biopsies was not influenced by both treatments. We conclude that an 8-week treatment with low dose hydrotalcite therapy is as effective as ranitidine in healing benign gastric ulcers and achieving pain relief.  相似文献   
30.
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