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81.
JA Zaia GM Gallez-Hawkins BR Tegtmeier A ter Veer X Li JC Niland SJ Forman 《Canadian Metallurgical Quarterly》1997,176(3):782-785
Late occurrence of cytomegalovirus (CMV) disease after day 100 after bone marrow transplantation has become an increasing problem; whether a quantitative measurement of CMV DNA in plasma by polymerase chain reaction (P-PCR) could be predictive of such disease was investigated. In a prospective study, 117 subjects undergoing allogeneic marrow transplantation were followed for 120 days with weekly CMV blood cultures, with day 35 bronchoalveolar lavage CMV cultures, with weekly CMV P-PCR, and with clinical follow-up for an additional 1-2 years. Despite preemptive ganciclovir, CMV disease occurred in 9% of subjects, with a median time of onset of 176 days. Quantitative CMV P-PCR was associated with the late development of CMV disease (P = .01). Of 43 subjects with positive P-PCR results, 23% developed CMV disease, but no disease occurred in the 74 subjects with negative P-PCR (P < .001), despite the fact that 22% had CMV isolated from lung lavage fluid and 32% had CMV isolated from blood. 相似文献
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The interactive editing and contouring of empirical fields 总被引:2,自引:0,他引:2
Dickinson R.R. Bartels R.H. Vermeulen A.H. 《Computer Graphics and Applications, IEEE》1989,9(3):34-43
A system for the interactive editing and contouring of surfaces derived from empirical fields is described. The approach taken begins with the representation of a field as a general-order, nonuniform, tensor-product, B-spline surface. It provides an interactive display for editing the surface by control-vertex manipulation and a contouring algorithm that is specifically designed for the fast and robust contouring of B-spline surfaces. Interactive editing of the resulting model is feasible because of the local nature of editing changes when B-splines are used. The use of nonuniform B-splines gives the flexibility required to model highly irregular data efficiently 相似文献
85.
SJ Geier PA Algate K Carlberg D Flowers C Friedman B Trask LR Rohrschneider 《Canadian Metallurgical Quarterly》1997,89(6):1876-1885
The macrophage colony-stimulating factor receptor and several other hematopoietic growth factor receptors induce the tyrosine phosphorylation of a 145- to 150-kD protein in murine cells. We have previously cloned a cDNA for the murine 150-kD protein, SHIP, and found that it encodes a unique signaling intermediate that binds the SHC PTB domain through at least one tyrosine phosphorylated (NPXY) site in the carboxyl-terminal region. SHIP also contains several potential SH3 domain-binding sites, an SH2 domain for binding other tyrosine phosphorylated proteins, and an enzymatic activity that removes the phosphate from the 5 position of phosphatidylinositol 3,4,5-phosphate or from inositol 1,3,4,5-phosphate. SHIP has a negative effect on cell growth and therefore loss or modification may have profound effects on hematopoietic cell development. In this study, we have cloned a cDNA for human SHIP and examined mRNA and protein expression of SHIP and related species in bone marrow and blood cells. Flow cytometry indicates that at least 74% of immature CD34+ cells express SHIP cross-reacting protein species, whereas within the more mature population of CD33+ cells, only 10% of cells have similar expression. The majority of T cells react positively with the anti-SHIP antibodies, but significantly fewer B cells are positive. Immunoblotting detects up to seven different cross-reacting SHIP species, with peripheral blood mononuclear cells exhibiting primarily a 100-kD protein and a CD34+ acute myeloblastic leukemia expressing mainly 130-kD and 145-kD forms of SHIP. Overall, these results indicate that there is an enormous diversity in the size of SHIP or SHIP-related mRNA and protein species. Furthermore, the expression of these protein species changes according to both the developmental stage and differentiated lineage of the mature blood cell. 相似文献
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A simple, rapid, accurate and reproducible capillary electrophoretic method was developed for the assay of glycyrrhizin and glycyrrhetinic acid in traditional Chinese medicinal preparations. The buffer solution used in this method was acetonitrile and 0.02 M sodium dihydrogen-phosphate solution adjusted to pH 7.5 with 0.05 M sodium hydroxide. The linear calibration range was 0.04-2.00 mg/ml (r = 0.9988) for glycyrrhizin and 0.007-0.35 mg/ml (r = 0.9985) for glycyrrhetinic acid and recoveries were 98.1-101.3% for glycyrrhizin and 98.5-101.4% for glycyrrhetinic acid. The relative standard deviations were 1.02% (n = 6) for glycyrrhizin and 0.91% (n = 6) for glycyrrhetinic acid. The content of these two acids in Glycyrrhizae Radix and Glycyrrhizae Radix-containing Chinese medicinal preparations was successfully determined within 10 min. 相似文献
87.
SJ Pocock 《Canadian Metallurgical Quarterly》1993,12(15-16):1459-69; discussion 1471-5
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