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131.
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Tuckerman JR Zhao Y Hewitson KS Tian YM Pugh CW Ratcliffe PJ Mole DR 《FEBS letters》2004,576(1-2):145-150
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Schlemminger I Mole DR McNeill LA Dhanda A Hewitson KS Tian YM Ratcliffe PJ Pugh CW Schofield CJ 《Bioorganic & medicinal chemistry letters》2003,13(8):1451-1454
Analogues of the naturally occurring cyclic hydroxamate dealanylalahopcin, which is an inhibitor of procollagen prolyl-4-hydroxylase, were synthesised and shown to be inhibitors of the human hypoxia-inducible factor prolyl hydroxylases. 相似文献
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Diffusion coefficient of cyclic GMP in salamander rod outer segments estimated with two fluorescent probes. 总被引:3,自引:1,他引:2 下载免费PDF全文
Experiments have demonstrated that single photoisomerizations in amphibian and primate rods can cause the suppression of 3-5% of the dark circulating current at the response peak (Baylor, D. A., T. D. Lamb, and K. W. Yau. 1979. J. Physiol. (Lond.). 288:613-634; Baylor, D. A., B. J. Nunn, and J. L. Schnapf. 1984. J. Physiol. (Lond.). 357:575-607). These results indicate that the change in [cGMP] effected by a single isomerization must spread longitudinally over at least the corresponding fractional length of the outer segment. The effective longitudinal diffusion coefficient, Dx, of cGMP is thus an important determinant of rod sensitivity. We report here measurements of the effective longitudinal diffusion coefficients, Dx, of two fluorescently labeled molecules: 5/6-carboxyfluorescein and 8-(fluoresceinyl)thioguanosine 3',5'-cyclic monophosphate, introduced into detached outer segments via whole-cell patch electrodes. For these compounds, the average time for equilibration of the entire outer segment with the patch pipette was approximately 6 min. Fluorescence images of rods were analyzed with a one-dimensional diffusion model that included limitations on transfer between the electrode and outer segment and the effects of intracellular binding of the dyes. The analyses yielded estimates of Dx of 1.9 and 1.0 microns 2.s-1 for the two dyes. It is shown that these results place an upper limit on Dx for cGMP of 11 microns2.s-1. The actual value of Dx for cGMP in the rod will depend on the degree of intracellular binding of cGMP. Estimates of the effective buffering power for cGMP in the rod at rest range from two to six (Lamb and Pugh, 1992; Cote and Brunnock, 1993). When combined with these estimates, our results predict that for cGMP itself, Dx falls within the range of 1.4-5.5 microns 2.s-1. 相似文献
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Sijeh A. Asuk Thomas J. Matthews Jonathan P. Sadler Thomas A. M. Pugh Vincent T. Ebu Nzube M. Ifebueme Nicholas Kettridge 《Biotropica》2023,55(1):232-245
Tropical forest tree communities are structured by a range of large-scale drivers including elevation, certain high-impact anthropogenic activities (e.g., deforestation), and fires. However, low-impact human activities such as foraging may also be subtly but notably altering the composition of tropical forest tree communities. The study assessed the (i) differences in species diversity, patterns of relative abundance, and pairwise beta diversity between trees with edible and inedible fruits and seeds along an elevation gradient, and (ii) impact of human foraging on the forest tree communities in Oban Division of Cross River National Park, Nigeria. Fifteen permanent 40 by 40 m plots were established along an elevational gradient (120–460 m above mean sea level). All trees of 0.1 m diameter at breast height (dbh) and above were measured, identified, and, with the aid of structured questionnaires, classified into those with edible and inedible fruits/seeds. A total of 35 edible species with density of 128 stems/hectare and basal area of 11.99 m2/hectare, and 109 inedible species with density of 364 stems/hectare and basal area of 22.42 m2/hectare were sampled. However, the evenness of edible and inedible species was similar at pooled and plot levels. For inedible species, there was a positive relationship between pairwise beta diversity and elevation, and this was driven mainly by turnover. In contrast, edible species exhibited a non-significant trend between elevation and beta diversity. Thus, the study showed that human foraging of edible fruits may have subtly influenced patterns of species diversity and community structure in this tropical forest. 相似文献
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Case records of post partum metritis in cows were obtained from Auburn University (42 cases) and Tuskegee University (36 cases) Large Animal Hospital files. Dairy cows (n=68) comprised 87.2% of the cases and beef (n=10) 12.8%. Age did not differ between the types, but the number of postpartum days at admission (mean +/- 1 SD) differed significantly (P=0.02) between dairy (7.3 +/- 4.27) and beef (3.7 +/- 4.06) cows. Older cows and those with hyperthermia were less likely to recover from puerperal metritis (P=0.07 and 0.03, respectively). Type of treatment had no significant association with survival. The number of days of hospitalization was associated with institution (P<0.001), number of postpartum days at admission (P=0.001), history of predisposing factors (P=0.0006), hyperthermia (P=0.006), and length of various treatments (P<0.001). However, the type of treatment had no significant association with length of hospitalization. This study suggests that the necessity for or type of therapy has little effect on the outcome of postpartum metritis. 相似文献