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41.
Buysmann S; Bemelman FJ; Schellekens PT; van Kooyk Y; Figdor CG; ten Berge IJ 《Blood》1996,87(1):404-411
We investigated the mechanism by which antihuman CD3 monoclonal antibodies of the isotypes IgG2a (eg, OKT3) and IgA (eg, IXA) can induce the rapid disappearance of virtually all circulating T lymphocytes. We hypothesize that upregulation of adhesion molecules on the lymphocyte membrane contributes to this effect. However, this hypothesis is difficult to test, because of the inherent lymphocytopenia and/or shifts in lymphocyte populations between intra and extra-vascular compartments. Therefore, studies in vitro were performed, as well. Analysis of peripheral blood lymphocytes isolated at several times after addition of OKT3 or IXA to whole blood of healthy individuals showed an immediate increase in the proportion of T cells expressing NKI-L16, an activation epitope on CD11a/CD18. Likewise, an increase in CD11b/CD18 expression occurred. In parallel experiments, a transiently increased adhesion of T cells to endothelial cell monolayers was observed. This adhesion could be completely blocked by anti-CD18 or anti-CD11a monoclonal antibodies and only partly by an anti-CD11b antibody. Our data indicate that upregulation of activation epitopes of CD11a/CD18, as well as increased expression of CD11b/CD18 on T lymphocytes, may result in increased adhesion of these cells to intercellular adhesion molecule-1 (ICAM-1) and ICAM-2 on vascular endothelium. This phenomenon may, at least, partly explain the rapidly occurring peripheral lymphocytopenia observed in vivo. 相似文献
42.
B lymphoblastoid cell lines with normal and defective O-glycosylation established from an individual with blood group Tn 总被引:2,自引:0,他引:2
Individuals with the Tn blood group contain terminal serine/threonine- linked N-acetylgalactosamine residues in their blood cells. This is due to lack of UDP-D-galactose: D-N-acetyl galactosamine beta-D-galactosyl transferase from part of their red cells and probably from their leukocytes. We have established B lymphoblastoid cell lines from such an individual by in vitro infection of his lymphocytes with Epstein- Barr virus. The original line contained a mixture of cells reactive and nonreactive with Helix pomatia lectin (Hp). These cells were subcloned after staining with fluorescent Hp by a fluorescence-activated cell sorter (FACS) into homogeneous, phenotypically stable lines of Hp- positive (Hp+) and Hp-negative (Hp-) cells. The molecular differences between the membrane glycoproteins were characterized by carbohydrate- specific surface labeling techniques, Hp affinity chromatography, polyacrylamide slab gel electrophoresis and glycopeptide/oligosaccharide analysis. The major O-glycosidic membrane glycoprotein (GP105) was retained on Hp-Sepharose columns only from Hp+ cells, whereas the common leukocyte antigen (GP160-200) was partially retained on Hp columns from both lines. These proteins were isolated by immune precipitation with monoclonal antibodies and characterized. The results show that the GP105 glycoprotein from Hp+ cells contains terminal N-acetylgalactosamine residues but also more complex oligosaccharides. The common leukocyte antigen showed different electrophoretic mobilities in Hp+ and Hp- cells. UDP-galactose D-N- acetyl galactosamine beta-galactosyl transferase was almost absent in the Hp+ cells. These cell lines are useful for studies on the functional role and regulation of the biosynthesis of O-glycosidic carbohydrates. 相似文献
43.
Extranodal malignant lymphoma: detection with FDG PET versus CT 总被引:19,自引:0,他引:19
Moog F; Bangerter M; Diederichs CG; Guhlmann A; Merkle E; Frickhofen N; Reske SN 《Radiology》1998,206(2):475
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NA Bridges A Cooke MJ Healy PC Hindmarsh CG Brook 《Archives of disease in childhood》1996,75(4):330-331
BACKGROUND: The pattern of growth of the uterus was examined by ultrasound examinations of 358 girls who attended a paediatric endocrine outpatient department but were shown not to have any endocrine defect. METHOD: The uterus was measured in length and width at the cervix and at the fundus (cm). Endometrial thickness was measured (mm). Scans were divided by Tanner breast stage and the dimensions compared by one way analysis of variance (ANOVA, with the Student Newman Keuls post hoc test). RESULTS: There was an increase in uterine length, diameter of the fundus, and endometrial thickness at each breast stage from 1 to 5 (ANOVA, p < 0.05), and in the diameter of the cervix with each breast stage from 1 to 4 (ANOVA, p < 0.05). The ratio of the fundus to the cervix increased from 0.95 to 1.29 between breast stages 1 and 4. CONCLUSION: The onset of puberty is marked by an increase in the dimensions of the uterus and in endometrial thickness, but also by a change in the shape of the uterus from a tubular to a pear shaped organ. 相似文献
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Van Nostrand D; Abreu SH; Callaghan JJ; Atkins FB; Stoops HC; Savory CG 《Radiology》1988,167(2):495-498
Since indium-111 white blood cell (In-111 WBC) scintigraphy is often used to evaluate for osteomyelitis in bone fractures, it is important to know if noninfected fractures have In-111 WBC uptake. Twenty-seven noninfected closed fracture sites in 19 patients were prospectively evaluated with technetium-99m methylene diphosphonate bone scintigraphy and In-111 WBC scintigraphy. In-111 WBC uptake was present in 41% of the 27 sites. In the 11 positive sites, the In-111 WBC uptake was 1+ (definite but minimal) in 55%, 2+ (moderate) in 36%, and 3+ (marked) in 9%. The visual intensity of the radioactive uptake on In-111 WBC scintigrams relative to that on bone scintigrams was less in 82%, equal in 9%, and greater in 9%. The visual size of the area of uptake on In-111 WBC scintigrams and bone scintigrams was smaller in 36%, equal in 55%, and greater in 9%. Factors that may help distinction of In-111 WBC uptake due to fracture alone from infection associated with fracture are discussed. 相似文献
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