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71.
Alison F. Richard 《Primates; journal of primatology》1976,17(3):357-366
In this paper, preliminary observations are presented on the ontogency of one of the Malagasy prosimians,Propithecus verreauxi. Observations were carried out in the course of an eighteen-month study of the social organization and ecology of four, free-ranging
groups. Parturition is described, together with data on the development of locomotor and feeding behavior, and on the changing
nature of the infant's relationship with its mother and with other members of the group. The final section compares the results
of this study with those of previous studies ofP. verreauxi and other lemur species. Tentative conclusions are drawn concerning aspects of social ontogeny inP. verreauxi and areas for future research are suggested which would clarify some of the remaining problems. 相似文献
72.
73.
H.O.J. Collier Alison A. Francis Wendy J. McDonald-Gibson S.A. Saeed 《Prostaglandins & other lipid mediators》1976,11(2):219-225
Sulphasalazine (SZ) inhibits prostaglandin (PG) biosynthesis with a potency comparable to that of aceylsalicylate. The metabolites of SZ, sulphapyridine and 5-aminosalicylic acid, were of considerably lower potency as inhibitors of PG biosynthesis in the synthetase preparations used. The inhibition of prostaglandin production by SZ could at least partly account for the clinical utility of sulphasalazine in ulcerative colitis. Sulphapyridine may help to maintain inhibitory concentrations of SZ by restraining bacterial breakdown of the active drug. 相似文献
74.
Alison R McTaggart 《BMJ (Clinical research ed.)》1983,286(6372):1214-1215
75.
Alison Streetly 《BMJ (Clinical research ed.)》1989,298(6684):1382-1383
76.
77.
Juanita K. Jellyman Malgorzata S. Martin-Gronert Roselle L. Cripps Dino A. Giussani Susan E. Ozanne Qingwu W. Shen Min Du Abigail L. Fowden Alison J. Forhead 《PloS one》2012,7(12)
Before birth, glucocorticoids retard growth, although the extent to which this is mediated by changes in insulin signalling pathways in the skeletal muscle of the fetus is unknown. The current study determined the effects of endogenous and synthetic glucocorticoid exposure on insulin signalling proteins in skeletal muscle of fetal sheep during late gestation. Experimental manipulation of fetal plasma glucocorticoid concentration was achieved by fetal cortisol infusion and maternal dexamethasone treatment. Cortisol infusion significantly increased muscle protein levels of Akt2 and phosphorylated Akt at Ser473, and decreased protein levels of phosphorylated forms of mTOR at Ser2448 and S6K at Thr389. Muscle GLUT4 protein expression was significantly higher in fetuses whose mothers were treated with dexamethasone compared to those treated with saline. There were no significant effects of glucocorticoid exposure on muscle protein abundance of IR-β, IGF-1R, PKCζ, Akt1, calpastatin or muscle glycogen content. The present study demonstrated that components of the insulin signalling pathway in skeletal muscle of the ovine fetus are influenced differentially by naturally occurring and synthetic glucocorticoids. These findings may provide a mechanism by which elevated concentrations of endogenous glucocorticoids retard fetal growth. 相似文献
78.
79.
The heights of some stranded shores in Gippsland, Australia, greatly exceed the level to which the ocean would rise if all present-day ice were to melt, and uplift is thus implied. Differences in level shown by comparison of these interglacial shorelines with others in South Carolina may therefore be the result of movement of one area relative to the other. Contemporary shorelines in the two localities can nevertheless be recognized from certain physiographic similarities and from the meagre measured age data presently available. We believe, furthermore, that there is sufficient information to permit estimation of the average rate of relative movement, and we attempt to analyse the field observations by applying a simple model that relates shoreline elevation to implied rate of uplift. This model is based on the supposition that the earth movements actually experienced were continuous, or can be reasonably represented as small fluctuations about a regular long-term trend. use of the model permits estimation of absolute ages (calculated from differences in altitude of correlated levels) for each high sea level stage that is recognized. Although the calculated or “altimetric” ages derived in this way are quite speculative, they agree with radiometric ages of Alaskan transgressions, interglacial littoral faunas, and warm intervals identified in deep-sea cores, and seem therefore to be verified by these comparisons. Particular correlations between high sea levels and warm core stages are implied: if these pairings are accepted, the altimetric ages can be re-estimated using the ages of the core stages. Predictions which use the calculated ages also provide tests of their value. 相似文献
80.
Geise Ribeiro Marcel Benadiba Denise de Oliveira Silva Alison Colquhoun 《Cell biochemistry and function》2010,28(1):15-23
The present study reports the synthesis of a novel compound with the formula [Ru2(aGLA)4Cl] according to elemental analyses data, referred to as Ru2GLA. The electronic spectra of Ru2GLA is typical of a mixed valent diruthenium(II,III) carboxylate. Ru2GLA was synthesized with the aim of combining and possibly improving the anti‐tumour properties of the two active components ruthenium and γ‐linolenic acid (GLA). The properties of Ru2GLA were tested in C6 rat glioma cells by analysing cell number, viability, lipid droplet formation, apoptosis, cell cycle distribution, mitochondrial membrane potential and reactive oxygen species. Ru2GLA inhibited cell proliferation in a time and concentration dependent manner. Nile Red staining suggested that Ru2GLA enters the cells and ICP‐AES elemental analysis found an increase in ruthenium from <0.02 to 425 mg/Kg in treated cells. The sub‐G1 apoptotic cell population was increased by Ru2GLA (22 ± 5.2%) when analysed by FACS and this was confirmed by Hoechst staining of nuclei. Mitochondrial membrane potential was decreased in the presence of Ru2GLA (44 ± 2.3%). In contrast, the cells which maintained a high mitochondrial membrane potential had an increase (18 ± 1.5%) in reactive oxygen species generation. Both decreased mitochondrial membrane potential and increased reactive oxygen species generation may be involved in triggering apoptosis in Ru2GLA exposed cells. The EC50 for Ru2GLA decreased with increasing time of exposure from 285 µM at 24 h, 211 µM at 48 h to 81 µM at 72 h. In conclusion, Ru2GLA is a novel drug with antiproliferative properties in C6 glioma cells and is a potential candidate for novel therapies in gliomas. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献