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排序方式: 共有1093条查询结果,搜索用时 31 毫秒
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Michael B Leahy Johannes T Dessens Friedemann Weber Georg Kochs Patricia A Nuttall 《Virus research》1997,50(2):215-224
The tick-borne Thogoto virus (THOV) is the type species of a newly recognized fourth genus, Thogotovirus, in the family Orthomyxoviridae. Because of the distant relationship of THOV with the influenza viruses, determination of its genomic information can potentially be used to identify important domains in influenza virus proteins. We have determined the complete nucleotide sequence of the second longest RNA segment of THOV. The molecule comprises 2212 nucleotides with a single large open reading frame encoding a protein of 710 amino acids, estimated Mr 81 284. The protein shares 77% amino acid similarity with the PB1-like protein of Dhori virus, a related tick-borne virus, and 50–53% with the PB1 polymerase proteins of influenza virus A, B and C. All the motifs characteristic of RNA-dependent polymerases were identified including the SSDD motif common to all RNA-dependant RNA polymerases, indicating that the THOV protein is functionally analogous to the influenza virus PB1 proteins and involved in chain elongation. We also report the corrected sequence of the third longest RNA segment of THOV, encoding a protein which shares 44–47% amino acid similarity with the PA-like polymerase proteins of influenza virus A, B and C. The biological significance of conserved domains in these orthomyxovirid proteins is discussed. 相似文献
3.
Inhibition of Dugbe nairovirus replication by human MxA protein 总被引:6,自引:0,他引:6
Sensitivity to the interferon-induced protein, MxA, has previously been demonstrated for viruses belonging to the Orthobunyavirus, Hantavirus and Phlebovirus genera of the Bunyaviridae family. We have extended these findings to a member of the fourth and remaining genus containing viruses that infect man and other animals, the nairovirus Dugbe virus (DUGV). Indirect immunofluorescence experiments using VA9 cells (Vero cells permanently transfected with MxA cDNA) revealed strongly reduced DUGV antigen expression, suggesting that MxA inhibited DUGV replication. Western and Northern blot analyses showed significantly lower DUGV nucleocapsid (N) protein expression and DUGV genomic RNA, respectively, in the presence of MxA. Viral titres were also reduced by more than two orders of magnitude in VA9 cells compared with control VN36 cells. This finding may have application to nairovirus therapeutics. 相似文献
4.
Neurophysiological brain activity evoked by individual spoken words and pseudowords was recorded and the mismatch negativity (MMN), an automatic index of experience-dependent auditory memory traces, was calculated. Consistent with earlier reported results, the MMN response to word-final syllables was enhanced compared with that elicited by the same syllables placed in a pseudoword context. Here we now demonstrate that the enhancement of the MMN elicited by two individual words showed different scalp topographies. The early word-specific brain activity is consistent with the assumption that the memory traces activated by individual words are carried by large neuronal ensembles that differ in their distributions over the cortex. Current source estimates localized the between-word differences in the right hemisphere and in parieto-occipital left-hemispheric areas. The differential brain responses to individual words appeared as early as ∼100 ms after the recognition points of the words, suggesting that their specific memory traces become active almost immediately after the information in the acoustic input is sufficient for word identification. 相似文献
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Honecker F Kersemaekers AM Molier M Van Weeren PC Stoop H De Krijger RR Wolffenbuttel KP Oosterhuis W Bokemeyer C Looijenga LH 《The Journal of pathology》2004,204(2):167-174
Intercellular contacts, mediated by E-cadherin, are essential for germ cell migration and maturation. Furthermore, it has been suggested that decrease or loss of E-cadherin correlates with tumour progression and invasive behaviour. beta-catenin is involved in a number of different processes, including cell--cell interaction when bound to cadherins, and determination of cell fate in pluripotent cells when activated via the Wnt signal-transduction pathway. To shed more light on the role of these factors in normal fetal germ cell development and the pathogenesis of germ cell tumours (GCTs), the present study investigated the presence and localization of E-cadherin and beta-catenin by immunohistochemistry. E-cadherin was only weakly expressed in or absent from fetal germ cells of the second and third trimesters, and was not expressed in carcinoma in situ/intratubular germ cell neoplasia unclassified (CIS/ITGCNU) and gonadoblastoma, the precursor of an invasive GCT in dysgenetic gonads. In GCTs, it was generally not expressed in seminoma and dysgerminoma, but was found in the vast majority of non-seminoma cells. beta-catenin was found in the cytoplasm of fetal germ cells at all gestational ages and in spermatogenesis in post-pubertal testes. It was also present in CIS/ITGCNU and gonadoblastoma. Whereas seminomas and dysgerminoma were negative, non-seminoma cells were frequently found to express beta-catenin. Expression of both factors therefore reflects the degree of differentiation of these tumours. No differences for either E-cadherin or beta-catenin were observed between samples of tumours resistant or sensitive to chemotherapy, and E-cadherin expression did not correlate with vascular invasion. E-cadherin and beta-catenin therefore play a role in both normal and malignant germ cell development and differentiation that warrants further investigation, but they seem to be of limited value as predictive or prognostic factors in GCTs. 相似文献
7.
Kh. R. Koczorek H. P. Wolff Marie-Luise Beer 《Journal of molecular medicine (Berlin, Germany)》1957,35(10):497-502
Ohne ZusammenfassungMit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
8.
Prof. Dr. med. Uwe Janssens Prof. Dr. med. Hilmar Burchardi Univ.-Prof. Dr. med. Gunnar Duttge Renate Erchinger Dr. med. Peter Gretenkort Prof. Dr. med. Michael Mohr Univ.-Prof. Dr. med. Friedemann Nauck Sonja Roth?rmel Prof. Dr. med. Fred Salomon Univ.-Prof. Dr. med. P. Schmucker PD Dr. phil. Alfred Simon Prof. Dr. med. Herwig Stopfkuchen Prof. Dr. med. Andreas Valentin Univ.-Prof. Dr. med. Norbert Weiler Dr. med. Gerald Neitzke 《MedR Medizinrecht》2012,30(10):647-650
9.
Rusman Tamara John Marie-Luise B. van der Weijden Mignon A. C. Boden Bouke J. H. van der Bijl Carmella M. A. Bruijnen Stefan T. G. van der Laken Conny J. Nurmohamed Mike T. van der Horst-Bruinsma Irene E. 《Clinical rheumatology》2020,39(5):1521-1529
Clinical Rheumatology - The primary aim is to evaluate signs of inflammation on MRI of sacroiliac joints (SIJ)/spine in inflammatory back pain (IBP) patients suspected of nr-axSpA with high disease... 相似文献
10.
Marie-Luise Alder Eva-Lotta Brakemeier Michael Dittmann Florian Dreyer Michael B. Buchholz 《Psychotherapie Forum》2016,21(1):2-10
A patient in a session of behavior therapy commits a Freudian parapraxis relevant for what follows in the session. This is taken as a starting point for a single case conversation analysis (CA). CA is a well known tool in psychotherapy process research. The role of theory as “sensitizing concept” is discussed as relevant for what we see how the therapist responds to the parapraxis. As psychoanalytic authors we got support in our view by Eva-Lotta Brakemeier, full professor for cognitive behavioral therapy at Psychologische Hochschule (PHB), Berlin. Questions of professional integration vs. difference between behavioral therapy and psychoanalysis can be discussed more fertile along such concrete examples. 相似文献