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BACKGROUND AND OBJECTIVES: Around 5% of chronic myeloid leukemias (CML) are characterized by complex variant Philadelphia (Ph) translocations involving one or more chromosomal regions in addition to 9 and 22. The BCR/ABL1 fusion gene is usually found on der(22). The additional gene(s) involved in complex variant Ph rearrangements have not been characterized. DESIGN AND METHODS: We performed fluorescent in situ hybridization (FISH) in three complex variant Ph translocations involving the short arm of chromosome 6 in addition to 9 and 22. The BCR/ABL1 D-FISH probe was applied to localize the BCR/ABL1 fusion gene as well as the 5'ABL1 and the 3'BCR. Locus-specific probes were used to narrow the 6p breakpoint. RESULTS: In all cases the BCR/ABL1 fusion gene was located on the Ph chromosome whereas the reciprocal ABL1/BCR gene was detected only in patient #2. On 6p, breakpoints were narrowed to three different regions: centromeric to the human major histocompatibility complex (MHC), between PAC 524E15 and PAC162J16, in the first patient, and telomeric to the MHC, between PAC 329A5 and PAC 145H9, and between PAC 136B1 and PAC 206F19, in the second and third patients, respectively. In patients #2 and 3 a chromosomal rearrangement different from a true complex variant was discovered. In both cases, a classical t(9;22) was associated with an additional translocation involving the der(9)t(9;22). INTERPRETATION AND CONCLUSIONS: Rearrangements at 6p in complex Ph aberrations involve more than one gene/locus. Classical t(9;22), masked by additional chromosomal rearrangements, can resemble complex variant Ph translocations, and can be detected only using appropriate FISH probes.  相似文献   
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Metabolic Brain Disease - Acetylcholine is an excitatory neurotransmitter that modulates synaptic plasticity and communication, and it is essential for learning and memory processes. This...  相似文献   
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Central line thrombosis in patients with cancer   总被引:1,自引:0,他引:1  
Central venous catheters are used frequently to care for patients with cancer and often serve as long-term venous access. Catheter-related central venous thrombosis is a serious and common complication in these patients. The incidence of this event ranges from 2 to 40%. Potential risk factors are catheter position, size of the catheter, and perhaps site of insertion. The diagnosis of catheter-associated deep venous thrombosis may be difficult. Doppler ultrasound has a lower accuracy in this setting than it does in symptomatic lower extremity venous thrombosis. No clinical management studies have validated the practice of withholding anticoagulant therapy in patients with a negative Doppler ultrasound. The practice of prophylaxis with low-dose warfarin or low-molecular-weight heparin has been recommended, although results from recent studies have called this into question. Larger, prospective, randomized trials with a uniform population of patients or stratification of risk factors will be essential to address this issue further.  相似文献   
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Summary. Red-cell studies were carried out on three groups of G6PD-deficient subjects with different G6PD variants from the Ferrara area of Northern Italy. Red-cell GSH and activities of G6PD, glutathione reductase (GR), glutathione peroxidase (GPx) and superoxide dismutase (SOD) were measured. A method was developed to measure red-cell GSH regeneration after oxidation of endogenous GSH in whole blood by diamide and only this clearly distinguished the variants from each other and from normal. Regeneration by 1 h was lowest in the Mediterranean variant, 0–10.2% in contrast to 93–98% in normal. A predisposition to a haemolytic crisis after ingestion of fava beans was not clearcut, but subjects appeared to be at risk if GSH regeneration at 1 h was less than 30% of the endogenous level, and red-cell FAD+ was very high indicated by high in vitro GR activity and inhibition by added FAD+.
It is suggested that the most informative tests in G6PD deficiency are measurements of GSH regeneration in intact red cells plus GR activity and/or red-cell flavin compounds.  相似文献   
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