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31.
Plasma hormones in pre- and postmenopausal breast cancer 总被引:1,自引:0,他引:1
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Edmund H. Frank Boyce W. Burge Boleslaw H. Liwnicz Linda J. Lotspeich Jocelyn C. White Steven L. Wechsler Frank H. Mayfield Jeffrey T. Keller 《Experimental cell research》1983,146(2):371-376
Cells from cranial and spinal arachnoid membranes of humans were grown in culture. Their growth characteristics, morphology and details of their cytoskeletal composition are described. Arachnoid membranes, obtained at autopsy, were finely minced and incubated in tissue culture medium. Monolayers of cells of homogeneous morphology grew from these tissue fragments. The cells were flat and polygonal. They divided slowly to form non-overlapping monolayers of low cell density. Electron microscopic examination of cultured arachnoid cells revealed numerous desmosome-like tight junctions and abundant intermediate filaments (tonofilaments). Both morphological features are characteristic of arachnoid cells in situ, but not of cells in the fibroblast-rich dura mater. Immunofluorescence microscopy with monoclonal antibodies demonstrated cytokeratin in the cytoplasm of primary cultures of arachnoid cells. Thus we demonstrated that these cultured cells retained certain of the specific differentiated properties of arachnoid cells in situ and that they are not fibroblasts (which lack tight junctions and cytokeratins). To our knowledge, there have been no previous reports of in vitro growth of arachnoid cells. This in vitro model should be useful in studying the response of arachnoid cells to a variety of substances thought to be involved in the chronic inflammatory condition of the meninges known as arachnoiditis. 相似文献
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Mark Andrews Alan Brown Jean-Yves Chiva David Fradet David Gordon Mark Lansdell Malcolm MacKenny 《Bioorganic & medicinal chemistry letters》2009,19(8):2329-2332
The reported selective serotonin Re-uptake Inhibitor Litoxetine was used as the starting point in the design of a range of potential SSRIs with high ease of synthetic accessibility. Preparation and subsequent optimization yielded a range of potent and highly selective SSRIs. 相似文献
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R Shapley J Gordon 《Proceedings of the Royal Society of London. Series B, Containing papers of a Biological character. Royal Society (Great Britain)》1980,209(1175):317-330
We measured the visual sensitivity of the conger eel retina by means of its electroretinogram (e.r.g.) and whole nerve responses. The spectral sensitivity of the retina closely corresponded to a prediction based on the density spectrum of the conger visual pigment, measured in situ. The pigment density in the conger eel retina is high, perhaps as high as 1.0. Thus, the predicted spectral sensitivity would be much broader than is observed if the absorption spectrum of the pigment governed the visual sensitivity. The reason why the visual spectral sensitivity corresponds to the density spectrum and not to the absorption spectrum is that the photoreceptors in the conger eye are arranged in tiers and only the inner tier contributes to vision. 相似文献
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Administration of high-dose Antide to ovariectomized monkeys results in rapid, prolonged, and reversible inhibition of gonadotropin secretion. The present study examined whether similar long-term control would be manifested in the menstrual cycle of intact primates. Antide administration at a dose of either 3.0 or 18.0 mg/kg induced rapid suppression of bioassayable LH concentrations, precipitating a concurrent fall in serum progesterone concentrations from 7.9 +/- 3.6 and 5.8 +/- 1.0 ng/ml (mean +/- SEM) on the day of injection to 0.6 +/- 0.2 and 0.5 +/- 0.1 ng/ml by 2 days post-treatment, respectively. This Antide-induced luteolysis was accompanied by the premature onset of menses within 3 days. The next menses following Antide administration was delayed. Ultimately, folliculogenesis culminating in normal follicular-phase estradiol production, ovulation, and subsequent normal luteal-phase progesterone production did occur in all treated monkeys. Menses resumed 54 +/- 9 and 75 +/- 13 days after treatment with 3.0 and 18.0 mg/kg Antide, respectively. No allergic cutaneous or peripheral reactions were seen, even at the highest dose of Antide. Thus, the long duration of action of high-dose Antide reported earlier in ovariectomized monkeys is also demonstrated in intact primates. These findings, along with the apparent absence of histamine-release effects even at high doses, suggest that Antide is a GnRH antagonist deserving clinical evaluation. 相似文献