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101.
K J Hogg R S Hornung C A Howie N Hockings F G Dunn W S Hillis 《British heart journal》1988,60(4):275-280
The predictive value of the measurement of changes in ST segment elevation was assessed as a non-invasive marker of coronary artery reperfusion after thrombolytic treatment. Forty five patients with acute myocardial infarction (23 anterior, 22 inferior) of less than six hours' duration were given thrombolytic treatment by either the intravenous (n = 28) or the intracoronary route (n = 17). A proportional value for the shift in ST segment, termed the fractional change, was calculated both from 12 lead electrocardiograms and from the Holter tape for each patient. Coronary artery patency in an initial group of 22 patients (training group) was associated with a fractional change value of greater than or equal to 0.5 (100% specific, 88% sensitive by Holter analysis; 100% specific, 94% sensitive by 12 lead electrocardiogram). This rule performed well when it was applied to a test group of 17 patients (100% specific, 93% sensitive by Holter analysis; and 67% specific, 93% sensitive by 12 lead electrocardiogram). Linear discriminant analysis was then used to determine which features gave the best separation of those in whom there was reperfusion and those in whom there was not. This gave 100% specificity and 100% sensitivity when applied to the training group for either the 12 lead electrocardiogram or Holter monitoring. When it was applied to the test group, the sensitivity was maintained at 100%, but the specificity dropped to 33% irrespective of whether the basis of the test was Holter monitoring or the 12 lead electrocardiogram. These results suggest that a fractional change of >/= 0.5 calculated from a single lead showing myocardial injury is a useful non-invasive marker of reperfusion. The technique can be applied to either 12 lead electrocardiograms or Holter monitoring. The use of a more complex classification increased the sensitivity of the test at the expense of its specificity. 相似文献
102.
A duplicated copy of DMRT1 in the sex-determining region of the Y chromosome of the medaka,Oryzias latipes 总被引:18,自引:0,他引:18
Nanda I Kondo M Hornung U Asakawa S Winkler C Shimizu A Shan Z Haaf T Shimizu N Shima A Schmid M Schartl M 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(18):11778-11783
The genes that determine the development of the male or female sex are known in Caenorhabditis elegans, Drosophila, and most mammals. In many other organisms the existence of sex-determining factors has been shown by genetic evidence but the genes are unknown. We have found that in the fish medaka the Y chromosome-specific region spans only about 280 kb. It contains a duplicated copy of the autosomal DMRT1 gene, named DMRT1Y. This is the only functional gene in this chromosome segment and maps precisely to the male sex-determining locus. The gene is expressed during male embryonic and larval development and in the Sertoli cells of the adult testes. These features make DMRT1Y a candidate for the medaka male sex-determining gene. 相似文献
103.
Thrombopoietin, but not erythropoietin promotes viability and inhibits apoptosis of multipotent murine hematopoietic progenitor cells in vitro 总被引:5,自引:3,他引:5
The recently cloned c-mpl ligand, thrombopoietin (Tpo), has been extensively characterized with regard to its ability to stimulate the growth, development, and ploidy of megakaryocyte progenitor cells and platelet production in vitro and in vivo. Primitive hematopoietic progenitors have been shown to express c-mpl, the receptor for Tpo. In the present study, we show that Tpo efficiently promotes the viability of a subpopulation of Lin-Sca-1+ bone marrow progenitor cells. The ability of Tpo to maintain viable Lin-Sca-1+ progenitors was comparable to that of granulocyte colony-stimulating factor and interleukin-1, whereas stem cell factor (SCF) promoted the viability of a higher number of Lin-Sca-1+ progenitor cells when incubated for 40 hours. However, after prolonged (> 40 hours) preincubation, the viability- promoting effect of Tpo was similar to that of SCF. An increased number of progenitors surviving in response to Tpo had megakaryocyte potential (37%), although almost all of the progenitors produced other myeloid cell lineages as well, suggesting that Tpo acts to promote the viability of multipotent progenitors. The ability of Tpo to promote viability of Lin-Sca-1+ progenitor cells was observed when cells were plated at a concentration of 1 cell per well in fetal calf serum- supplemented and serum-depleted medium. Finally, the DNA strand breakage elongation assay showed that Tpo inhibits apoptosis of Lin-Sca- 1+ bone marrow cells. Thus, Tpo has a potent ability to promote the viability and suppress apoptosis of primitive multipotent progenitor cells. 相似文献
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H. J. Møller H. Aerts H. Grøbæk N. A. Peterslund P. Hyltoft Petersen N. Hornung 《Scandinavian journal of clinical and laboratory investigation》2013,73(7):29-33
By immunoprecipitation we have identified a soluble plasma form of CD163 (sCD163), the IL-6 inducible macrophage-receptor for clearing haptoglobinhaemoglobin complexes. A sandwich ELISA for measuring sCD163 was established and used to determine the sCD163 levels in normal subjects and patients with inflammatory and myeloproliferative diseases. In normal subjects, the concentration of sCD163 was high (median 1.9 mg/l) with low intraindividual variation. Highly increased levels were seen in patients with sepsis, myeloid leukaemia and in patients with Gaucher disease characterized by accumulation of tissue macrophages. Although the physiological role of sCD163 remains unknown, our present data suggest that sCD163 might prove to be a valuable marker molecule in infectious and myeloproliferative diseases. 相似文献
107.
Dr. M.M. Wölfler W. Rath D. Hornung N. Maass I. Meinhold-Heerlein 《Der Gyn?kologe》2010,43(11):895-900
Endometriosis is one of the most common benign diseases among premenopausal women. However, after years of extensive research, it is still impossible to correctly diagnose endometriosis without an operation. Protein detection and proteomic techniques like two-dimensional gelelectrophoresis (2DE) and mass spectrometry (MS) are applicable to explore pathognomonic processes by comparison of sera from endometriosis patients and from normal controls, respectively. Therefore, these techniques may reveal novel diagnostic markers for endometriosis. While single protein markers or panels of markers may presently enter clinical application, “high throughput” screening techniques like protein pattern profiling remain experimental due to exalted technology and costs. Moreover, 2DE is an excellent technique to research unknown pathways and detect differentially expressed proteins when additionally subjected to tandem mass spectrometry (MS/MS) for protein identification. This might lead to the discovery of new diagnostic and potentially therapeutic markers. 相似文献
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