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We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I–II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases.   In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL.   Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival.  相似文献   
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Acquired Loss of Red-Cell Wj Antigen in a Patient with Hodgkin''s Disease   总被引:2,自引:0,他引:2  
A patient with Hodgkin's disease became temporarily Wj-negative with alloanti-Wj in his serum. Four human autoantibodies, and 1 of 2 murine monoclonal antibodies, with serological characteristics of anti-Wj were nonreactive with his red cells, confirming that they have anti-Wj specificity. Six siblings of the patient are all Wj-positive. The patient was also temporarily Anton-negative, and cross-testing between Wj and Anton red cells and antisera showed mutual compatibility, indicating that the antigens are the same. The patient and 3 of his 6 siblings are also of the rare Lu: - 13 phenotype, providing the first evidence that this is an inherited characteristic.  相似文献   
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It is recognised that stromal cells determine cancer progression. We have previously shown that active TGFβ produced by rat colon carcinoma cells modulated NO production in rat endothelial cells. To elucidate the role of TGFβ and NO in the mechanisms of interaction of colon carcinoma cells with stromal cells and in cancer progression, we transfected REGb cells, a regressive colon carcinoma clone secreting latent TGFβ, with a cDNA encoding for a constitutively-secreted active TGFβ. Out of 20 injected rats only one tumour progressed, which was resected and sub-cultured (ReBeta cells). ReBeta cells secreted high levels of active TGFβ. The adhesive properties of REGb and Rebeta cells to endothelial cells were similar, showing that the secretion of active TGFβ is not involved in tumour cell adhesion to endothelial cells. ReBeta, but not REGb, cell culture supernatants inhibited cytokine-dependent NO secretion by endothelial cells, but inhibition of NO production was similar in co-cultures of REGb or ReBeta cells with endothelial cells. Therefore, secretion of active TGFβ regulated endothelial NO synthase activity when tumour cells were distant from, but not in direct contact with, endothelial cells. However, only ReBeta cells inhibited cytokine-dependent secretion of NO in coculture with macrophages, indicating that the active-TGFβ–NO axis confers an advantage for tumour cells in their interaction with macrophages rather than endothelial cells in cancer progression.  相似文献   
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Loss of human chromosomes from mouse × human hybridomas is not random. Human chromosomes 14, 5 and 22 are preferentially retained, while chromosomes 2 and 1 are preferentially lost. Interestingly, human chromosome 14, which carries the genes for human immunoglobulin heavy chains, appears to be retained by almost all the hybrid clones and subclones.  相似文献   
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ObjectivesAcute hospitalization may lead to a decrease in muscle measures, but limited studies are reporting on the changes after discharge. The aim of this study was to determine longitudinal changes in muscle mass, muscle strength, and physical performance in acutely hospitalized older adults from admission up to 3 months post-discharge.DesignA prospective observational cohort study was conducted.Setting and ParticipantsThis study included 401 participants aged ≥70 years who were acutely hospitalized in 6 hospitals. All variables were assessed at hospital admission, discharge, and 1 and 3 months post-discharge.MethodsMuscle mass in kilograms was assessed by multifrequency Bio-electrical Impedance Analysis (MF-BIA) (Bodystat; Quadscan 4000) and muscle strength by handgrip strength (JAMAR). Chair stand and gait speed test were assessed as part of the Short Physical Performance Battery (SPPB). Norm values were based on the consensus statement of the European Working Group on Sarcopenia in Older People.ResultsA total of 343 acute hospitalized older adults were included in the analyses with a mean (SD) age of 79.3 (6.6) years, 49.3% were women. From admission up to 3 months post-discharge, muscle mass (?0.1 kg/m2; P = .03) decreased significantly and muscle strength (?0.5 kg; P = .08) decreased nonsignificantly. The chair stand (+0.7 points; P < .001) and gait speed test (+0.9 points; P < .001) improved significantly up to 3 months post-discharge. At 3 months post-discharge, 80%, 18%, and 43% of the older adults scored below the cutoff points for muscle mass, muscle strength, and physical performance, respectively.Conclusions and ImplicationsPhysical performance improved during and after acute hospitalization, although muscle mass decreased, and muscle strength did not change. At 3 months post-discharge, muscle mass, muscle strength, and physical performance did not reach normative levels on a population level. Further research is needed to examine the role of exercise interventions for improving muscle measures and physical performance after hospitalization.  相似文献   
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The Tau model of phenotypic transmission has been used to analyze the familial correlations (nuclear families and extended families) of longevity at Arthez d'Asson (individuals born between 1686 and 1899). At birth, the transmissibility (t2) is very weak: 0·103; at 20 years old, t2 = 0·167; at 50 years old, t2 = 0·294. The effect of sibling environment on children's phenotype is s = 0·086 at birth, is thus null. A cohabitional effect between spouses: p = 0·167 appears after 50 years. There is no social homogamy effect via grandparents.  相似文献   
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