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The patient is a 12-year-old boy with acute mixed lineage leukemia (AMLL) and with a rare karyotype of trisomy 6. He was referred to our hospital with gingival swelling, bleeding at the conjunctiva and huge hepatosplenomegaly. Complete blood count revealed leukocytosis with 79% blasts, anemia and thrombocytopenia. Bone marrow examination revealed 82.5% blasts which were morphologically judged as M1 according to the French-American-British classification. Immunophenotyping of leukemic cells showed the presence of CD2, CD7, CD19 and CD13 antigens, suggesting the diagnosis of AMLL. Cytogenetic analysis revealed a single abnormal karyotype of 47,XY,+6,add(15)(q22) which was successfully detected by fluorescence in situ hybridization (FISH) with the probe mapping at the alpha-satellite region of chromosome 6. Although the patient was treated with several chemotherapy regimens, he could not achieve complete remission and he died of progressive disease 11 months after admission. Fluorescence in situ hybridization analysis was very informative in assessing the residual leukemic cells in interphase during his clinical course.  相似文献   
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Elongation factor Tu (EF-Tu) is a G-protein which, in its active GTP conformation, protects and carries aminoacylated tRNAs (aa-tRNAs) to the ribosome during protein biosynthesis. EF-Tu consists of three structural domains of which the N-terminal domain consists of two special regions (switch I and switch II) which are structurally dependent on the type of the bound nucleotide. Structural studies of the complete functional cycle of EF-Tu reveal that it undergoes rather spectacular conformational changes when activated from the EF-Tu.GDP form to the EF-Tu.GTP form. In its active form, EF-Tu.GTP without much further structural change interacts with aa-tRNAs in the so-called ternary complex. The conformational changes of EF-Tu involve rearrangements of the secondary structures of both the switch I and switch II regions. As the switch II region forms part of the interface between domains 1 and 3, its structural rearrangement results in a very large change of the position of domain 1 relative to domains 2 and 3. The overall shape of the ternary complex is surprisingly similar to the overall shape of elongation factor G (EF-G). Thus, three domains of the protein EF-G seem to mimic the tRNA part of the ternary complex. This macromolecular mimicry has profound implications for the function of the elongation factors on the ribosome.  相似文献   
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Patients with preterm labor not only suffer from anxiety and uncertainty regarding the healthy development of their child but, especially as inpatients, in part severely from loss of autonomy and feelings of insufficiency. By the creative therapeutic means of art therapy it is aimed at influencing the disturbed emotional state and strengthening self-esteem. During the sessions patients experience challenge, success and relaxation with endurance some time after the sessions. Paintings produced by hospitalized patients in art therapeutic sessions are presented. Further psychophysiological investigations are in process for controlling the effects on preterm labor. Paintings of inpatients are discussed.  相似文献   
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Devices and techniques used for pediatric cardiopulmonary bypass are ever changing. There are frequently reports in the literature about new techniques and new devices. Periodic surveys are helpful because they reveal the actual extent to which these techniques and devices are applied to clinical practice. Advances in research are bringing about a better understanding of the intricate aspects of CPB and the effects of CPB on pediatric patients. There appears to be a trend from widely divergent approaches to CPB for pediatric patients to more uniformity in practice. For example, the use of membrane oxygenation and arterial line filtration has become universal, and there is an increase in the use of all types of safety devices. Techniques reported in the medical literature at the beginning of the decade, such as, the use of modified ultrafiltration, the use of centrifugal cell washers to process packed red blood cells before adding them to the prime, and the use of the antifibrinolytic drug, aprotinin, have become part of practice at a large number of pediatric heart centers. Periodic surveys are useful, as they provide a measurement of current practice. They also provide a historical record of the advances in the field.  相似文献   
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Cloning and characterization of a Choristoneura fumiferana ultraspiracle (Cfusp) cDNA are described. First, a PCR fragment and then a cDNA clone (4.4 kb) were isolated from spruce budworm cDNA libraries. Comparison of the deduced amino acid sequence of this cDNA with the sequences in Genbank showed that this sequence had high homology with the ultraspiracle cDNAs cloned from Drosophila melanogaster (Dmusp), Bombyx mori (Bmusp), Manduca sexta (Msusp), and Aedes aegypti (Aausp). The Cfusp cDNA contained all the regions that are typical for a steroid/thyroid hormone receptor superfamily member. The DNA binding domain or C region was the most conserved sequence among all the usps. The A/B, D, and E regions also showed high amino acid identity with the amino acid sequences of Dmusp, Msusp, Bmusp, and Aausp. The Cfusp 4.5-kb mRNA was present in the embryos, in all larval stages, and in the pupae. The Cfusp mRNA levels in the midgut increased during the sixth-instar larval development and reached peak levels during the ecdysteroid raises for the pupal molt. However, Cfusp mRNA levels remained unchanged in the midgut of fifth-instar larvae, and in the epidermis and fat body of sixth-instar larvae indicating both a tissue- and stage-specific regulation of Cfusp mRNA expression.  相似文献   
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We propose an account of comparison asymmetries based on viewing comparison as a process of structural alignment and mapping. Specifically, we hypothesize that (1) comparison asymmetries result from directional differences in informativity, and that (2) asymmetries can therefore be predicted from the relative degree of systematicity or conceptual coherence of the items being compared. In Experiment 1, we found a clear preference for placing the more systematic of two passages in the base position of a comparison. Experiments 1 and 2 further showed that structural alignability is crucial in obtaining such asymmetries. In Experiment 3, we found that asymmetries are predicted by the relative systematicity of the comparisons items rather than by the relative size of the distinctive feature sets. These results are inconsistent with accounts of asymmetry based on feature contrast or stimulus bias. In Experiments 4 through 6, we tested the functional implications of our account by examining inference projection and perceived informativity across asymmetric comparisons. Critically, comparisons having the more systematic item as the base were more likely to result in inference projection and other forms of target modification and were rated as more informative than reverse comparisons. We conclude by demonstrating that this account can explain comparison asymmetries without positing underlying asymmetries in subjective similarity, and that it offers a unified approach to the directionality of literal comparisons, analogies, and metaphors.  相似文献   
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