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991.
研究了在促进剂Cu2+和抑制剂2,4-D及光的作用下,对产色素培养细胞紫草宁形成的影响。对4,15,25,35和45d的紫草培养细胞的电镜观察和细胞超微结构分析的结果表明,15d加促进剂Cu2+的新疆紫草培养细胞形成的色素颗粒(紫草宁)最多,4d和加抑制剂2,4-D的培养细胞中均无明显的色素颗粒。 相似文献
992.
993.
Primary cultures of gill cells from freshwater and seawater-adapted trout were compared. These cultures, developed from an explant technique, exhibited a similar growth. Ultrastructural comparison between cultured and in situ cells showed that most of the cells in primary culture resembled the so called 'pavement' cells, whereas chloride cells were not observed in the cultured epithelium. Several other cells types, representing a minority of cells in primary culture, were observed (mucous cells, vesicolar cells, cells with large dense granules and cells containing lysosomes). Morphological observations of cultured pavement cells from freshwater and seawater trout gills were similar, although the density of cellular organelles in cells was less under freshwater conditions. In addition to the morphological comparison, the regulation of intracellular pH in cultured cells from freshwater and seawater gills was examined. Resting pHi was not different for freshwater or seawater gill cells. A sodium-dependent and amiloride-sensitive mechanism was found in cultured cells. Under the experimental conditions used here, this mechanism was most likely a Na+/H+ antiporter in pavement cells from freshwater and seawater-adapted trout. The comparison of pHi recovery after acidification of cells from freshwater and seawater gills showed that the activity or the number of antiporters was higher for cells from seawater trout gill. 相似文献
994.
This study documented the effect of cadmium on salmon parr and smolt gill morphology. Cadmium-induced changes in chloride cell (CC) cytoskeletal elements were investigated, as well as the modifications of CC surface area and density. In cadmium-treated parr (10 µg Cd l-1 for 2 days), immunofluorescent light microscopy revealed the appearance of an intense actin staining located in the CC apical part. Transmission electron microscopic observations revealed a change in the organization of the microfilaments at the CC apex, with the appearance of numerous aggregates of filamentous actin. Higher cadmium concentrations (30 and 50 µg l-1) and prolonged treatment times (7 to 14 days) did not modify such reorganisation. Microtubules were not significantly affected by similar treatments. Further, scanning electron microscopic analysis revealed that cadmium induces a significant increase of parr CC surface area as early as the second day of exposure. After 2 days, mature CC density had also increased. In smolt, a rise in CC surface area was observed, although CC density did not significantly increase. 相似文献
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997.
Construction of a telomerase-immortalized porcine tracheal epithelial cell model for swine-origin mycoplasma infection 下载免费PDF全文
XIE Xing HAO Fei WANG Hai-yan PANG Mao-da GAN Yuan LIU Bei-bei ZHANG Lei WEI Yan-na CHEN Rong ZHANG Zhen-zhen BAO Wen-bin BAI Yun SHAO Guo-qing XIONG Qi-yan FENG Zhi-xin 《农业科学学报》2022,21(2):504-520
Primary porcine tracheal epithelial cells(PTECs) are an appropriate model for studying the molecular mechanism of various porcine respiratory diseases, including swine-origin mycoplasmas, which are isolated from respiratory tract of pigs and mainly found on the mucosal surface surrounding swine trachea. However, the short proliferation ability of primary PTECs greatly limits their lifespan. In this study, primary PTECs were carefully isolated and cultured, and immortal PTECs were constructed by ... 相似文献
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999.
It has been established that secretion of gonadotropin (GtH) and growth hormone (GH) release in goldfish are both stimulated
by GtH-releasing hormone (GnRH); in addition GtH secretion is inhibited by dopamine D2 mechanisms. In the present study, depletion of protein kinase C (PKC) in goldfish pituitary cells reduced the GtH and GH
responses to GnRH and an activator of PKC in static culture. In perifusion studies, GtH released in response to sGnRH analog
was greatly attenuated in PKC-depleted cells, however, hormone responses to forskolin were enhanced. Stimulation of dopamine
D2 receptors reduced the GtH, but not the GH, responses elicited by PKC activators. These results indicate that PKC participates
in the GtH and GH responses to natural neuroendocrine regulators in the goldfish.
Résumé Il a été établi que chez le poisson rouge, les sécrétions de gonadotropine (GtH) et d'hormone de croissance (GH) sont toutes les deux stimulées par la gonadolibérine (GnRH); de plus, la sécrétion de GtH est inhibée par des mécanismes dopaminergiques de type D2. Dans le présent travail, la déplétion de la teneur en protéine kinase C (PKC) dans des cellules hypophysaires de poisson rouge réduit les résponses en GtH et GH au GnRH et à un activateur de la PKC de cellules maintenues en incubation statique. Dans des cellules maintenues en périfusion et soumises à une déplétion en PKC, la GtH libérée en réponse à un analogue du sGnRH est fortement diminuée, cependent les réponses hormonales à la forskoline sont augmentées. La stimulation des récepteurs dopaminergiques D2 réduit, dans le cas d'action d'activateur de la PKC, la réponse en GtH mais pas en GH. Ces résultats indiquent que la PKC est impliquée dans les mécanismes de régulation de GtH et GH par des facteurs neuroendocriniens naturels.相似文献
1000.