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111.
Background: The role of the villi and vesicles of the epicardium primordium in the formation of the epicardium has been extensively studied over the last decades. With regard to the cellular contents of the villi and vesicles of the epicardium primordium, in quail the presence of mesenchymal cells in the villi recently has been described. In the present study, we have determined whether the villi and vesicles of the epicardium primordium in rat embryos contain mesenchymal cells that originate from the transverse septum and if so, whether these cells will become part of the subepicardium. Methods: Mesenchymal cells in the transverse septum of rat embryos were labelled by a method consisting of in vitro whole embryo culture and labelling of the ectoderm and its daughter cells, using wheat germ agglutinin-gold (WGA-Au) as a marker. Results: In concordance with our observations in the standard noncultured rat embryos, labelled cells were present in the transverse septum, extending from the umbilical ring, i.e., the transition of amniotic epithelium to ectoderm, up to the villi, in the villi and vesicles, and subepicardially. Conclusions: These observations suggest that the epicardium primordium contains mesenchymal cells derived from the transverse septum. These cells reach the subepicardium, using the villi and vesicles of the epicardium primordium as their vehicle. © 1995 Wiley-Liss, Inc.  相似文献   
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Interpretation of CT scans with PACS image display in stack mode   总被引:4,自引:0,他引:4  
Mathie  AG; Strickland  NH 《Radiology》1997,203(1):207
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Iron promotes DEN initiated GST-P foci in rat liver   总被引:3,自引:0,他引:3  
Diethylnitrosamine (DEN) was administered to rats as a single dose, which is known not to give rise to liver tumours without subsequent promotion. Iron dextran (Fe/Dex) was then administered parenterally to the animals, to induce iron overload. At 3 and 6 months after the final Fe/Dex treatments, livers were examined quantitatively for the numbers of the placental form of glutathione-S-transferase (GST-P) expressing foci, the area occupied by these foci and their size distribution. The results demonstrate that iron not only increased the number of foci after DEN initiation in the rat liver, but that the area occupied by these lesions increased significantly between 3 and 6 months after initiation. There is no evidence that iron increased the number of GST- P expressing foci present in rats not exposed to DEN. This indicates that iron did not act as an initiator in this rodent model of liver cancer. The increase in the area of the liver occupied by the foci in iron and DEN treated rats was due to an increase in the size of the foci, as well as to an increase in the number of foci. This is the first demonstration that iron can act as a promoter of DEN initiated hepatocytes. It also demonstrates that fibrogenesis is not an absolute requirement for the promotion, by iron, of liver foci in the rat, and that this could also be the case for iron overload in man. Iron may also act as a promoter of already initiated hepatocytes in the development of human liver cancer, as it does in the rat.   相似文献   
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Indian Journal of Thoracic and Cardiovascular Surgery -  相似文献   
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Neutrophil dermatosis of the dorsal hands (NDDH) is a recently described skin manifestation regarded as a subset of acute febrile neutrophilic dermatotis (Sweet syndrome). We describe 5 cases with pustular and ulcerative plaques and/or bullae and vesicles of the dorsal hands. Three of the patients also had skin changes at sides other than the hands. Associated conditions were found in two patients, one patient treated with hemo-dialysis for chronic glomerulonephritis, and one patient had suffered from a streptococcal tonsillitis prior to the eruption. Two of the patients had fever, two had neutrophil leucocytosis in peripheral blood and two had elevated sedimentation rates. Histological findings showed signs of vasculitis in biopsies from two of the patients. NDDH is discussed on the basis of prior case reports concerning the subject, and it is concluded that Neutrophil dermatosis of the dorsal hands should be regarded as a localized variety of Sweet syndrome.  相似文献   
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