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High frequency oscillation and exogenous surfactant in the treatment of neonatal respiratory distress syndrome 总被引:1,自引:0,他引:1
Surfactant therapy has become widely used in neonates suffering from respiratory distress syndrome. High frequency oscillation has been shown to be efficient and safe in animal models, but somewhat less convincing in human neonates. An overview is given of the experimental and clinical data assessing the combination of these two techniques. Personal preliminary data are briefly presented. 相似文献
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To precisely determine the genotype of Epstein-Barr virus (EBV) in Hodgkin's disease (HD), we simultaneously analyzed three divergent gene loci (EBNA-2, EBNA-3C, and EBER) that distinguish type A and B viruses. The primers designed to amplify these three gene loci encompass either type-specific deletion sequences (EBNA-2 and EBNA-3C) or type-specific point mutations (EBER) that identify the virus strain based on the sizes of the polymerase chain reaction (PCR)-amplified products or the mobility shifts in single-strand conformation polymorphism analysis. The locations of point mutations were identified by direct sequencing of the PCR-amplified DNA. We analyzed 15 EBV-infected cell lines and found a good correlation between EBNA-2 and EBNA-3C typing results. In contrast, approximately 33% of the cell lines analyzed maintained type A sequences in EBNA-2 and EBNA-3C genes while carrying type B sequences in the EBER region. Data obtained from analysis of cell lines served as a reference for studying HD samples. EBV DNA was detected in about 70% of HD. Among the EBV-positive samples, 56% were associated with type A virus, 13% with type B, and 31% with dual viral sequences. Thus, type A virus is predominant in HD. Based on the histology, the frequencies of EBV positivity were 83%, 71%, and 33% for mixed cellularity, nodular sclerosis, and lymphocyte predominance, respectively. The detection of high frequency of both type A and B sequences in HD may provide a lead in investigating the role of dual viral infection in EBV pathogenesis. 相似文献
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Percutaneous abdominal biopsy: cost-identification analysis 总被引:1,自引:0,他引:1
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Identification, chromosomal mapping and tissue-specific expression of hREV3 encoding a putative human DNA polymerase zeta 总被引:5,自引:0,他引:5
Xiao W; Lechler T; Chow BL; Fontanie T; Agustus M; Carter KC; Wei YF 《Carcinogenesis》1998,19(5):945-949
The Saccharomyces cerevisiae REV3 gene encodes the catalytic subunit of a
non-essential DNA polymerase zeta, which is required for mutagenesis. The
rev3 mutants significantly reduce both spontaneous and DNA damage- induced
mutation rates. We have identified human cDNA clones from two different
libraries whose deduced amino acid sequences bear remarkable homology to
the yeast Rev3, and named this gene hREV3. The hREV3 gene was mapped to
chromosome 1p32-33 by fluorescence in situ hybridization. The hREV3 encodes
an mRNA of >10 kb, and its expression varies in different tissues and
appears to be elevated in some but not all of the tumor cell lines we have
examined. In light of recent reports of a putative mouse REV3, these
results indicate that mammalian cells may also contain a mutagenic pathway
which aids in cell survival at the cost of increased mutation.
相似文献
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Breast disease: dynamic spiral MR imaging 总被引:19,自引:0,他引:19