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51.
Cloning and analysis of the murine Fanconi anemia group C cDNA   总被引:7,自引:1,他引:7  
Fanconi anemia (FA) is one of a group of disorders characterizedat the cellular level by a combination of hypersensitivity toDNA-damaging agents, chromosomal instability, and defectiveDNA repair. Clinical features of FA include pancytopenia, oftenaccompanied by specific congenital malformations, and a predispositionto leukemia. Since the hematological manifestations are thecritical defect in terms of prognosis, FA is a candidate diseasefor gene replacement therapy, and the development of a mousemodel system is essential for the initial stages of this work.Previously, we have cloned the gene defective in FA group Cby complementation of the intrinsic sensitivity of FA cellsto DNA cross-linking agents. We have now cloned the murine homologueof the human FACC cDNA. The mouse cDNA (Facc) shares 79% aminoacid sequence similarity with the human gene product. The expressionof the mouse cDNA in human FA(C) cells restores the cellulardrug sensitivity to normal levels. Thus, the function of theprotein has been conserved despite the significant sequencedivergence. PCR analysis of mouse tissue RNA reveals that thegene is expressed in all adult tissues, while in situ RNA hybridizationexperiments show tissue specific expression at late stages offetal development. Cross-hybridizing sequences exist in DNAfrom other mammals, chicken and Drosophila. These results supportthe hypothesis that the FACC gene product has a role in a basicaspect of cellular protection against DNA damaging agents andthat this function has been conserved during evolution.  相似文献   
52.
53.
Low-molecular-weight organosilane polymers were prepared by sodium coupling of dichloro-methylphenylsilane ( 1 ) with chlorotrimethylsilane ( 2 ). Gel permeation chromatography (GPC), IR and NMR (1H, 13C and 29Si) analysis of the crude product ( 3 ) were performed and compared with those of the isolated first oligomers, trisilane ( 3a ) and tetrasilane ( 3b ). The GPC characteristics, especially high resolution ones, in accordance with the α,ω-bis(trimethylsilyl)-oligo(methylphenylsilane) structure are compared with those of hydrocarbon polymers. The relations of the NMR characteristics of the methylphenylsilanediyl unit with the position along the chain and the configuration of the diads are approached. Some spectroscopic indications of the secondary structure are discussed.  相似文献   
54.
Kabuki syndrome (KS) is associated with multiple organ system involvement. Characteristic features include long palpebral fissures with everted lower lids, prominent ears, skeletal abnormalities, mental retardation, and short stature. An increased incidence of infection has been reported in KS, and a few patients have been noted to have immune defects. However, the frequency and severity of the immune deficiency has not been clearly defined. Immunologic evaluation of 19 consecutive individuals with KS was performed at The Children's Hospital of Philadelphia. Decreased IgA levels were noted in 15/19 individuals (79%), 2 of whom had undetectable levels. Eight patients (42%) also had low total IgG levels. Specific IgG subclass abnormalities were found in 6 of 13 patients evaluated. IgM levels were less frequently decreased. One patient failed to generate anti-tetanus antibodies despite immunization. This study suggests that hypogammaglobulinemia is a frequent finding in children with KS. The pattern of antibody abnormalities seen in children with KS resembles common variable immune deficiency (CVID). Due to this increased susceptibility to infection, children with KS should have immunologic evaluations at the time of diagnosis in order to reduce preventable morbidity and mortality.  相似文献   
55.

Background  

Assessment of cerebral blood flow (CBF) by SPECT could be important in the management of patients with severe traumatic brain injury (TBI) because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia), or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets.  相似文献   
56.
There is some evidence that, in asthma, mast cells infiltrate the airway smooth muscle layer and, as a consequence, alter the functional and structural properties of myocytes. This inflammation so-called mast-cell myositis, probably contributes to both bronchial hyperresponsiveness and airway remodelling. Previous observations have pointed out the presence of mast cells within airway smooth muscle of atopic patients and recent data obtained in asthmatic patients demonstrate that this infiltration is more important in asthmatic patients with atopy. Although the mechanism of such a mast cell attraction remains to be fully understood, experimental data demonstrate that, upon stimulation by tryptase or cytokines, smooth muscle cells can attract mast cells through the production of TGF-beta1 or SCF. Once at the site of inflammation, activated mast cells are responsible for an important extracellular deposition of inflammatory products that may facilitate the increase in smooth muscle mass. In addition, comparison of asthmatic patients with and without atopy suggests that mast cell myositis is closely related with atopy.  相似文献   
57.
The role of coupling between prefrontal and temporo-parietal brain areas within the theta frequency range of the human electroencephalogram was explored in a working memory task. During encoding of visual information higher theta amplitudes were observed in the right compared to the left hemisphere. Retrieval of visuospatial and verbal information elicited a more bilateral activation pattern. These effects were accompanied by theta coupling between dorsolateral prefrontal and right posterior temporal electrode sites during encoding. During retrieval prefrontal and bilateral temporo-parietal brain areas were coupled. These results support the idea of working memory functions being dependent on distributed prefrontal-temporal networks.  相似文献   
58.
The purpose of this study is to evaluate the usefulness of the new real-time PCR COBAS TaqMan 48 analyzer, comparing it to the existing COBAS AMPLICOR HBV MONITOR based on conventional PCR technology. The study used 104 samples from different patients. No differences were found in the sensitivity of the tests. There was an excellent correlation between the sample with a viral load within the dynamic range of the two tests (r = 0.938). The COBAS TaqMan test has a wider linear range, and this fact enables quantifying of the viral load without diluting the sample.  相似文献   
59.
Electroconvulsive therapy (ECT) is an effective and safe treatment for depression. Anticoagulation therapy is used to reduce morbidity or mortality from stroke or recurrent pulmonary embolus in various cardiac and vascular conditions. We report in detail the successful ECT treatment of a patient suffering from major depression with psychotic features who continued warfarin (Coumadin) anticoagulant therapy.  相似文献   
60.
Prevention Science - Despite the availability of efficacious and effective family-based interventions, such interventions are scarce for sexual minority adolescents, particularly among...  相似文献   
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