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81.
82.
Gastrointestinal stromal tumors (GISTs)--the Lebanese experience 总被引:1,自引:0,他引:1
Salamoun W El Hajj G Aftimos G Moukharbel N Khairallah S Bejjani N Abou Sleiman CH Abou Atmeh J Azar H Elias E Abi Gerges D 《Molecular immunology》2003,39(17-18):1129-1132
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Surface markers of lymphocytes in the snake, Spalerosophis diadema. I. Investigation of lymphocyte surface markers. 总被引:2,自引:0,他引:2
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A specific antiserum was raised in rabbits against thymocytes from snakes, Spalerosophis diadema, and was absorbed repeatedly with snake erythrocytes and kidney cells. In complement-dependent cytotoxicity assays, the absorbed anti-thymocyte serum (ATS) was, at any given dilution, cytotoxic to Sp. diadema thymocytes > peripheral blood lymphocytes (PBL) > spleen cells and could be titrated to a plateau defining a population of about 98% of thymocytes, 80% of PBL and 72% of spleen cells. Antiserum directed against snake immunoglobulins was obtained by injecting rabbits with gamma-globulins separated from snake serum by DEAE-cellulose filtration. the anti-gamma globulin serum was absorbed with snake erythrocytes, and in indirect membrane immunofluorescence stained no thymocytes while reacted with about 15% of PBL and 29% of spleen lymphocytes up to a 1:8 dilution. Fluorescence of positive cells was distributed in spots, patches or caps; cap formation could be inhibited by maintaining the immunofluorescence test at +4 degrees. In each of six separate experiments performed during spring, the percentage of lymphocytes which reacted with anti-snake gamma-globulin serum complemented the percentage of cells recognized by ATS. It was shown, furthermore, that about 3%, 8% and 21% of lymphocytes from thymus, peripheral blood and spleen, respectively, possess a receptor for 2-mercaptoethanol-insensitive antibody-sheep erythrocyte complexes. The results indicate that lymphocyte structural heterogeneity exists in reptiles. 相似文献
85.
Chemokine receptor expression on human eosinophils from peripheral blood and bronchoalveolar lavage fluid after segmental antigen challenge 总被引:4,自引:0,他引:4
Liu LY Jarjour NN Busse WW Kelly EA 《The Journal of allergy and clinical immunology》2003,112(3):556-562
BACKGROUND: The recruitment of circulating eosinophils to the lung is a characteristic feature of allergic airway inflammation. Chemokine receptors likely play a role in this complex process. However, reports of chemokine receptor expression on human eosinophils are conflicting. OBJECTIVE: The aim of this study was to determine whether the chemokine receptor profile of human eosinophils change when these cells are recruited to the airway after an antigen challenge and development of an allergic inflammatory response. METHODS: Blood and bronchoalveolar lavage (BAL) cells were obtained from 13 allergic subjects 48 hours after segmental bronchoprovocation with antigen. The CC chemokine receptor (CCR) 1 to 7, 9, and CXC chemokine receptor (CXCR) 1 to 4 were determined by flow cytometric analysis of whole blood and unseparated BAL cells. RESULTS: Compared with their circulating counterparts, airway eosinophils had decreased CCR3 and increased CCR4, CCR9, and CXCR3 expression on their cell surface. Furthermore, expression of CCR3, CCR4, and CXCR3 was significantly correlated with the percentage of eosinophils in BAL fluid at 48 hours. Eosinophils also expressed CXCR4, but this receptor did not change after antigen-induced recruitment to the airway. In contrast, the expression of CCR1, CCR2, CCR5, CCR6, CCR7, CXCR1, and CXCR2 remained undetectable on either blood or BAL eosinophils. CONCLUSIONS: Our data suggest that recruitment of eosinophils to the airway is associated with a modulation of their chemokine receptor profiles. These changes in chemokine receptors could be involved in determining eosinophil function and antigen-induced airway inflammation. 相似文献
86.
El Benna J Hayem G Dang PM Fay M Chollet-Martin S Elbim C Meyer O Gougerot-Pocidalo MA 《Inflammation》2002,26(6):273-278
Superoxide anion (O2°-)production by neutrophil NADPH oxidase participates in arthritic joint lesion formation. Proinflammatory cytokines such as tumor necrosis factor (TNF), interleukin 8 (IL-8) and granulocyte/macrophage-colony stimulating factor (GM-CSF) have a priming effect on neutrophil NADPH oxidase activity. NADPH oxidase activation is dependent on phosphorylation of p47phox, a cytosolic component of the enzyme. We studied O2°-production and p47phox phosphorylation in synovial fluid (SF) from patients with rheumatoid arthritis (RA) and spondylarthropathy (SpA) according to TNF, IL-8 and GM-CSF levels. O2°-production by neutrophils isolated from SF of all the arthritis patients (RA and SpA) was higher than that of circulating resting neutrophils and when stimulated with fMLP or PMA. In addition, p47phox was partially phosphorylated in SF neutrophils compared to circulating neutrophils. High levels of TNF and IL-8 (but not GM-CSF) are detected in patient's SF (compared to circulating blood levels). TNF levels were significantly higher in RA than in SpA SF. These results suggest that increased NADPH oxidase activity could be involved in arthritic joint inflammation through increased p47phox phosphorylation. This could be the result of the presence of high levels of priming agents such as TNF and IL-8 but not GM-CSF. 相似文献
87.
Vázquez-García M Elías-Viñas D Reyes-Guerrero G Domínguez-González A Verdugo-Díaz L Guevara-Guzmán R 《Physiology & behavior》2004,82(4):685-690
The effect of exposure to low-frequency electromagnetic fields (ELF EMFs) on social recognition was studied. The test was based upon a comparison between two encounters of an adult rat and a conspecific juvenile, separated by an interexposure interval (IEI). The exposure to ELF EMF of 1 mT intensity during 2 h for 9 days increased the duration of short-term memory of adult male Wistar rats up to 300 min. These data indicate, for the first time, that ELF EMF improves social recognition memory in rats. 相似文献
88.
We have compared the use of two (93 and 185 keV) and three (93, 185, and 300 keV) photopeaks for Ga-67 tumor imaging and optimized the placement of each energy window. METHODS: The bases for optimization and evaluation were ideal and Bayesian signal-to-noise ratios (SNR) for the detection of spheres embedded in a realistic anthropomorphic digital torso phantom and ideal SNR for the estimation of their size and activity concentration. Seven spheres of radii ranging from 1 to 3 cm, located at several sites in the torso, were simulated using a realistic Monte Carlo program. We also calculated the ideal SNR for the detection from simple phantom acquisitions. RESULTS: For detection and estimation tasks, the optimum windows were identical for all sphere sizes and locations. For the 93 keV photopeak, the optimal window was 84-102 keV for the detection and 87-102 keV for estimation; these windows are narrower than the 20% window often used in the clinic (83-101 keV). For the 185 keV photopeak, the optimal window was 170-220 keV for the detection and 170-215 keV for estimation; these are substantially different than the 15% window used in our clinic (171-199 keV). For the 300 keV photopeak, the optimal window for detection was 270-320 keV, and for estimation, 280-320 keV. Using the three optimized, rather than only the two lower-energy, windows yielded a 9% increase in the SNR for the detection of the 3 cm diam sphere (a 12% increase for a 2 cm diam sphere) and a 7% increase in the SNR for estimation of its size. For the acquired phantom data, detection also increased by 9%-12% when using three, rather than two, energy windows. 相似文献
89.
Radosława Nowak Elżbieta Oknińska‐Hoffmann Agata Skórka Dorota Gieruszczak‐Białek Maria Sawadro‐Rochowska 《American journal of medical genetics. Part A》2001,103(2):144-148
Wiedemann‐Rautenstrauch (neonatal progeroid) syndrome is an autosomal recessive condition with characteristic appearance of premature aging present at birth (aged face, natal teeth, and wrinkled skin). Other features of the syndrome are generalized lipoatrophy with specific fat accumulation in the lateral suprabuttock region, hypotrichosis, macrocephaly (pseudohydrocephalus), and mental retardation. We report on a new case that demonstrates all typical features of the syndrome. The girl is now 16 years and 10 months old and has had follow‐up from birth. We measured terminal restriction fragment (TRF) length to evaluate whether the patient's premature aging process is accompanied by shortening of telomere length in her cultured fibroblasts. Mean TRF of 13.5 kb found in our patient's fibroblasts is not shortened as compared to that of normal fibroblasts. Our results differ from those observed in Hutchinson‐Gilford progeria. © 2001 Wiley‐Liss, Inc. 相似文献
90.