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Staining and histochemical methods, immunofluorescence, and electron microscopy were used to individualize the prolactin cells in the adenohypophyseal pars distalis of the nonhibernating hedgehog. One cell type was differentiated; their characteristics at the light and electron microscopic levels were presented. Immunofluorescence has confirmed the functional significance of this cell type and the validity of the denomination 'prolactin cells'. 相似文献
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P Dubois P Stein D Ennist D Greenblatt T Mosmann M Howard 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(6):1927-1934
We report here a role of B cell stimulatory factor 1 (BSF-1) in the induction of antigen-specific proliferation of affinity-purified small B lymphocytes by a thymus-dependent antigen and a carrier-reactive T cell line. By using an ovalbumin-reactive T cell line (designated Hen-1), which does not produce BSF-1 following activation, it was possible to demonstrate that the antigen-specific proliferative response of trinitrophenyl (TNP)-binding B cells to TNP-ovalbumin required exogenous BSF-1 in addition to direct interaction with irradiated Hen-1 T cells. The activation obtained under these conditions was highly efficient, being sensitive to antigen doses as low as 0.001 microgram/ml. The addition of saturating amounts of BSF-1 did not alter the antigen-specificity or the requirements for hapten-carrier linkage or major histocompatibility complex-restricted T-B interaction in this system. The involvement of BSF-1 was confirmed by the ability of 11B11 anti-BSF-1 antibody to specifically suppress the response of TNP-binding B cells to TNP-ovalbumin, BSF-1, and irradiated Hen-1 T cells. Finally, this response was augmented by addition of the monokine interleukin 1. These data indicate that the proliferative response of small B cells to the thymus-dependent antigen and carrier-reactive T cell line used in our experiments can be regulated by the same factors that govern B cell proliferation induced by thymus-independent type 2 antigens or anti-IgM antibodies. 相似文献
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Staining and histochemical methods, immunofluorescence and electron microscopy were used to individualize the thyrotropic cells in the adenohypophysis of the non-hibernating hedgehog. One cell type was differentiated; its characteristics at the light and electron-microscopic levels were presented. Immunofluorescence has confirmed the functional significance of this cell type and the validity of the denomination of 'thyrotropic cells'. 相似文献
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Dr. Michel Jangoux Philippe Dubois Anne Lambert Catherine Yourassowsky 《Cell and tissue research》1985,242(3):657-660
Summary A microcanalicular network is demonstrated within the ossicle stroma and the dermal tissue of two asteroid species. Microcanaliculi are presumed to be mesodermal structures. They consist of convoluted tubular ducts lined by epithelial cells associated with scattered basiepithelial nervous processes. Such a microcanalicular system has not been reported previously from any echinoderm species. Its discovery in asteroids entails some conceptual changes, especially considering the physiology of the body wall.Research assistants of the National Fund for Scientific Research (NFSR, Belgium) 相似文献
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Immunocytochemistry and radioimmunoassay were used to assess the appearance time and tissue distribution of vasoactive intestinal peptide (VIP) in the digestive tract of the human fetus. By radioimmunoassay, VIP was measurable from 10 weeks of gestation. The peptide was abundantly distributed in the jejuno-ileum and colon, where the tissue peptide concentration rose from 9-14 weeks of gestation (18.4 +/- 4.4 and 22.0 +/- 5.0 pmol/g wet weight, respectively) to 15-21 weeks (83.0 +/- 21.1 and 98.6 +/- 36.4 pmol/g, respectively). Lower concentrations were recorded in pancreas from 9-14 weeks of gestation (4.3 +/- 0.8 pmol/g) to 15-21 weeks (13.9 +/- 3.7 pmol/g). The peptide concentration was 15.6 +/- 1.9 pmol/g in fundus and 25.5 +/- 3.2 pmol/g in antrum from 15 to 21 weeks of gestation. The highest concentration was recorded in duodenum from 15 to 21 weeks of gestation (118.4 +/- 40.8 pmol/g wet weight). Tissue VIP concentration and age were positively correlated in the jejuno-ileum. By immunofluorescence, immunoreactive VIP was localized in nervous fibers in the muscularis externa, in the submucosa and in the lamina propria. Scarce cell bodies were also found in the myenteric plexus. No immunofluorescent endocrine cells were observed. These results suggest: (1) the early appearance of immunoreactive VIP in gut, as early as 10 weeks of gestation; (2) the peptide, localized in nervous structures only, follows the same distribution pattern as that in adults; (3) the development of VIPergic structures is a continuous process, initiated during the 3rd month of pregnancy. 相似文献
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Hemming Fiona J. Begeot Martine Dubois Maurice P. Dubois Paul M. 《Cell and tissue research》1983,234(2):427-437
Corticotropes of rat fetuses aged 16, 18 and 21 days were localized by the indirect antibody-enzyme method on semithin sections of the pituitary. The development of the ultrastructure of these cells was observed on consecutive ultrathin sections. In comparison with previous data our present results show that identification of a fetal cell type cannot be based entirely on morphological criteria. The structural peculiarities of corticotropes obtained from studies in vivo are compared with those observed in cells maintained in vitro. 相似文献