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排序方式: 共有333条查询结果,搜索用时 13 毫秒
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Immunoglobulin and T cell receptor gene configuration in acute lymphoblastic leukemia of infancy 总被引:1,自引:0,他引:1
Felix CA; Reaman GH; Korsmeyer SJ; Hollis GF; Dinndorf PA; Wright JJ; Kirsch IR 《Blood》1987,70(2):536-541
We examined immunoglobulin (Ig) heavy chain, K light chain, and T cell receptor (TCR) gamma and beta gene configuration in the leukemic cells from a series of infants aged less than 1 year with acute lymphoblastic leukemia (ALL). Each of these 11 cases demonstrated leukemic cell surface antigens that have been correlated with a B cell precursor phenotype. Of the 11, lymphoblasts of 4 retained the germline configuration of both Ig and TCR loci, whereas 7 had rearranged the Ig heavy chain gene. Two of these seven showed light chain gene rearrangement. TCB beta chain rearrangement had occurred in only one of the 11 patients' tumors. No TCR gamma chain rearrangements were identified. These results are in contrast to earlier studies of B cell precursor ALL in children in which Ig heavy chain gene rearrangements were evident in every case and approximately 40% showed Ig light chain rearrangement as well. In addition, 45% of cases of B cell precursor ALL of children had rearranged their gamma TCR genes, and 20% had rearranged beta. These data suggest that ALL in infancy represents an earlier stage of B cell development than is found in B cell precursor ALL of children. ALL in the infant age group has been associated with the worst prognosis of all patients with ALL. This study suggests that the disease in infants differs not only clinically, but also at the molecular genetic level, from the disease in children. 相似文献
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Activities of enzymes of the purine metabolic pathway, adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), and 5'- nucleotidase (5'-N), were investigated in the lymphoblasts of a patient with B-cell acute lymphoblastic leukemia. These lymphoblasts exhibited increased ADA activity and diminished activities of both PNP and 5'N' as compared to normal lymphocytes as well as non-T, non-B leukemia cells. This enzymatic pattern is identical to that which has been described in T-cell leukemic lymphoblasts and differs from that which has been observed in the malignant cells of undifferentiated B-cell lymphomas. These data suggest that there is biochemical heterogeneity within the spectrum of B-cell malignancies. Furthermore, inhibitors of ADA may be of use in those B-cell lymphoid neoplasms that exhibit increased ADA activity. 相似文献
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HELEN HØGH PETERSEN XU CHEN ADRIAN PIETERSEN JESPER HASTRUP SVENDSEN STIG HAUNSØ 《Pacing and clinical electrophysiology : PACE》1998,21(1):322-326
This study was designed to investigate the effect of the convective cooling of the tip of the ablation electrode during temperature controlled radiofrequency ablation. In vivo two different application sites in the left ventricle of anaesthetised pigs were ablated and in vitro ablation was performed during two different flow-velocities in a tissue bath, while electrode contact pressure and position were unchanged. Target temperature was 80 °C. Obtained tip temperature, power consumption and lesion dimensions were measured. In vivo lesion volume, depth and width were found significantly larger for septal applications than apical applications (p<0.01) and more power was used (p<0.001). Obtained tip temperature was significantly lower in the septal applications (p<0.001). In vitro increased convective cooling by induction of flow yielded larger lesion volume, depth and width (p<0.01), and had higher power consumptions (p<0.01). Obtained tip temperature did not differ significantly. For the given chosen target temperature power consumption was positively related to lesion volume (r= 0.66 in vivo and 0.65 in vitro), whereas obtained tip temperature was not (r = - 0.49 in vivo and - 0.61 in vitro). We conclude that during temperature controlled radiofrequency ablation lesion size differs for septal and apical left ventricular applications. Differences in convective cooling might play an important role in this respect. This is supported by our in vitro experiments, where increased convective cooling by induction of a flow around the electrode tip increases lesion dimensions and power consumptions. Furthermore we conclude that for the given target temperature the power consumption is positively correlated with lesion volume (p<0.001), whereas the obtained tip temperature is not. 相似文献
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