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排序方式: 共有2219条查询结果,搜索用时 15 毫秒
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P Sinibaldi R Muraro M Centanni M G Giganti 《Bollettino della Società italiana di biologia sperimentale》1983,59(1):112-116
The behaviour of Na+/K+ ATPase during cell growth has been studied. Human cultured fibroblasts were used in the presence or absence of EGF. Sample and control cultures were stopped by gathering and washing the cells with tris buffer. Homogenates were tested for Na+/K+ ATPase activity by the method of incubating and for the -SH groups content (Ellman). Na+/K+ ATPase activity that slightly increases in the controls is strongly reduced by the addition of EGF. The behaviour shows evidence for a double mechanism of action: I) involvement of the cAMP system 2) decrease of the -SH group availability. 相似文献
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L D'Agostino S Pignata B Daniele R Ventriglia G Ferrari C Ferraro S Spagnuolo P E Lucchelli G Mazzacca 《Biochimica et biophysica acta》1989,993(2-3):228-232
Plasma diamine oxidase (DAO) values are enhanced by intravenous injection of heparin which releases the enzyme, synthesized in small bowel enterocytes, from binding sites located on endothelial cells of the intestinal microvasculature. Intestinal DAO, in analogy with lipoprotein lipase (another heparin-released enzyme), is believed to be electrostatically linked to endothelial binding sites composed of a glycosaminoglycan (GAG) which is presumably heparan sulphate, but the complete mechanism of enzyme release is not known. In this study we assayed in rats the DAO-releasing capability of heparan sulphate, dermatan sulphate, chondroitin sulphate A and hyaluronic acid, all heparin related compounds. Heparan sulphate, a compound with the same hexosamine as heparin but with a lower concentration of sulphated iduronic acid, induced a very high release of DAO (3-fold less than heparin), while the other tested GAGs, composed of higher proportions of non sulphated uronic acid and with galactosamine instead of glucosamine, induced a significantly lower release. In rats treated with 60 mg heparan sulphate the significant decrease in ileal mucosal DAO activity indicates that, in analogy with heparin, the high plasma enzymatic activity induced is of enterocytic origin. It is suggested that the high charge density of the compounds tested, due to the degree of sulphatation, is the decisive factor in promoting the release of intestinal DAO. 相似文献
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Daniele Arobba Andrea Quaglia Paolo Panagia Paolo Minuti Sergio Innocenti Pier Luigi Odda 《Aerobiologia》1988,4(1-2):38-46
Riassunto Sono state rilevate durante un monitoraggio aerobiologico effettuato a Pietra Ligure (Savona) nel corso del 1987 le concentrazioni
polliniche di 50 taxa ed è stata valutata l'influenza relativa dei fattori meteorologici. Le osservazioni palinologiche sono
state rapportate alle concentrazioni sieriche delle IgE specifiche, alla reattività bronchiale specifica ed aspecifica valutate
in 101 pazienti allergici (rinitici ed asmatici), sensibilizzati a Graminaceae ed Urticaceae (Parietaria) al fine di riconoscere
correlazioni tra le caratteristiche aerobiologiche di questi allergeni edi meccanismi patogenetici che sostengono la reattività
bronchiale.
相似文献
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Arsenio Corrado Negrini Renato Ariano Guiseppina Delbono Antonio Ebbli Antonio Quaglia Daniele Arobba 《Aerobiologia》1992,8(3):355-358
Summary The authors examined 734 sensitised patients living in four localities in Liguria (Genoa, Savona, Pietra Ligure and Sanremo). The commonest source of sensitisation (62.7%) was Urticaceae (Parietaria), followed by Poaceae (52.5%) andOlea europaea L. (24.0%). A survey of airborne pollens revealed a greater presence of Urticaceae and Poaceae in Genoa and of Oleaceae in Pietra Ligure and Sanremo. 相似文献
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Francis Chaouloff Guy A. Kennett Bernard Serrurrier Daniele Merino Gerald Curzon 《Journal of neurochemistry》1986,46(5):1647-1650
Rats were trained to run on a horizontal treadmill for 2 h at 20 m/min. This activity considerably increased plasma free tryptophan (TRP) (+70%) but did not alter plasma total TRP levels and had little or no effect on plasma concentrations of the other large neutral amino acids (LNAAs) that compete with TRP for entry into the brain. Brain TRP levels increased by 80%. The only other brain LNAA to be affected by exercise was threonine, which rose moderately. The results indicate that increased plasma free TRP was specifically responsible for the increase of brain TRP after 2 h of exercise. Brain lysine was also increased whereas glycine, alanine, and gamma-aminobutyric acid were decreased. The differences between the present findings and those previously obtained following 2 h immobilization stress are discussed. 相似文献
10.
Differential interleukin 1 elaboration by unfractionated and density fractionated human alveolar macrophages and blood monocytes: relationship to cell maturity 总被引:10,自引:0,他引:10
J A Elias A D Schreiber K Gustilo P Chien M D Rossman P J Lammie R P Daniele 《Journal of immunology (Baltimore, Md. : 1950)》1985,135(5):3198-3204
The elaboration of interleukin 1 (IL 1) by mononuclear phagocytes is important in the regulation of human inflammatory and fibrotic reactions. Mononuclear phagocytes are morphologically and functionally heterogeneous cells. To further understand the processes controlling inflammation and fibrosis, in particular that in the human lung, we studied the elaboration of IL 1 by unfractionated and density-fractionated human alveolar macrophages and blood monocytes. Stimulated blood monocytes elaborated more IL 1 than stimulated alveolar macrophages. In addition, denser alveolar macrophages and blood monocytes elaborated more IL 1 than less dense alveolar macrophages and monocytes. Lastly, as monocytes matured in vitro, they lost their ability to elaborate IL 1 and became less dense. Thus, there is variability between and within mononuclear phagocyte cell populations in their ability to elaborate IL 1. These differences may result in part from differences in cell maturation. 相似文献