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891.
Association of TLR4 polymorphisms with Mycobacterium avium subspecies paratuberculosis infection status in Canadian Holsteins 下载免费PDF全文
B. S. Sharma M. K. Abo‐Ismail F. S. Schenkel Q. You C. P. Verschoor S. D. Pant N. A. Karrow 《Animal genetics》2015,46(5):560-565
Mycobacterium avium ssp. paratuberculosis (MAP) causes chronic enteritis in cattle that results in substantial financial losses to the cattle industry worldwide. Given that susceptibility to MAP infection is determined in part by genetics, marker‐assisted selection may help in the breeding of animals that are more resistant to MAP infection. The toll‐like receptor 4 gene (TLR4) was selected as a potential candidate gene because of its role in innate immunity and its involvement in MAP recognition and infection. The objective of this study, therefore, was to identify associations between TLR4 polymorphisms and susceptibility to MAP infection in Canadian Holstein cows. Two biologically relevant SNPs, including c.‐226G>C in the 5′‐untranslated region and the non‐synonymous SNP c.2021C>T in the potential TIR domain, were selected for an association analysis with MAP infection status in 409 Canadian Holsteins. The haplotype C‐T from these combined SNPs yielded significant association with susceptibility to MAP infection, supporting the involvement of TLR4 in susceptibility to MAP infection. 相似文献
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The aim of this study is to evaluate the physiological costs and the consequences on fitness of cold exposure on the parasitoid
Aphidius ervi (Hymenoptera: Aphidiinae) under non-lethal conditions. We exposed 1-day-old mummies to different treatments: control at 20°C,
7°C constant, 7°C fluctuating (7°C for 22 h and 20°C for 2 h). Two performances of fitness were particularly affected after
two weeks at 7°C constant: female longevity and the sex ratio of the progeny was male biased. In contrast, egg load at emergence,
lifetime fecundity, frequency of asymmetric individuals in both sexes, and mating success were not significantly affected
under all treatments. The effects of these treatments on trends such as utilisation of fat reserves and fertility of males
and females are discussed. 相似文献
894.
We consider a chain of metabolic reactions catalyzed by enzymes, of reversible Michaelis-Menten type with full dynamics, i.e. not reduced with any quasi-steady state approximations. We study the corresponding dynamical system and show its global stability if the equilibrium exists. If the system is open, the equilibrium may not exist. The main tool is monotone systems theory. Finally we study the implications of these results for the study of coupled genetic-metabolic systems. 相似文献
895.
The generalized nonlinear Klien-Gordon equation plays an important role in quantum mechanics. In this paper, a new three-time level implicit approach based on cubic trigonometric B-spline is presented for the approximate solution of this equation with Dirichlet boundary conditions. The usual finite difference approach is used to discretize the time derivative while cubic trigonometric B-spline is applied as an interpolating function in the space dimension. Several examples are discussed to exhibit the feasibility and capability of the approach. The absolute errors and error norms are also computed at different times to assess the performance of the proposed approach and the results were found to be in good agreement with known solutions and with existing schemes in literature. 相似文献
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Stephen Neidle Ismail M. Ismail Peter J. Sadler 《Journal of inorganic biochemistry》1980,13(3):205-212
X-ray crystallography shows that Pt(NH3)2(CBDCA) is a square-planar complex with the dicarboxylate chelate ring in the boat conformation and a planar cyclobutane ring. 1H and 13C nmr studies suggest that rapid chelate ring flipping occurs in solution. The value of 195Pt nmr combined with 15N labeling as an informative new method of studying carboxylate coordination is illustrated. nmr results are also reported for the analogous ethylmalonate complex. 相似文献