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301.
Mapping QTL for production traits in segregating Piétrain pig populations using genome‐wide association study results of F2 crosses 下载免费PDF全文
In this study, genome‐wide association study (GWAS) results of porcine F2 crosses were used to map QTL in outcross Piétrain populations. For this purpose, two F2 crosses (Piétrain × Meishan, n = 304; Piétrain × Wild Boar, n = 291) were genotyped with the PorcineSNP60v2 BeadChip and phenotyped for the dressing yield, carcass length, daily gain and drip loss traits. GWASs were conducted in the pooled F2 cross applying single marker mixed linear models. For the investigated traits, between two and five (in total 15) QTL core regions, spanning 250 segregating SNPs around a significant trait‐associated peak SNP, were identified. The SNPs within the QTL core regions were subsequently tested for trait association in two outcross Piétrain populations consisting of 771 progeny‐tested boars and 210 sows with their own performance records. In the sow (boar) dataset, five (eight) of the 15 mapped QTL were validated. Hence, many QTL mapped in the F2 crosses (with Piétrain as a common founder breed) are still segregating in the current Piétrain breed. This confirms the usefulness of existing F2 crosses for mapping QTL that are still segregating in the recent founder breed generation. The approach utilizes the high power of an F2 cross to map QTL in a breeding population for which it is not guaranteed that they would be found using a GWAS in this population. 相似文献
302.
Herbert J. Gans 《Ethnic and racial studies》2013,36(2):173-192
‘Second‐generation decline’ questions the current American faith in the myth of nearly automatic immigrant success. In discussing economic scenarios, positive and negative, for the future of the children of the post‐1965 immigrants, the possibility is proposed that a significant number of the children of poor immigrants, especially dark‐skinned ones, might not obtain jobs in the mainstream economy. Neither will they be willing ‐ or even able ‐ to take low‐wage, long‐hour ‘immigrant’ jobs, as their parents did. As a result, they (and young males among them particularly) may join blacks and Hispanics among those already excluded, apparently permanently, from the mainstream economy. The article also deals with the relations between ethnicity and economic conditions in the USA and with the continued relevance of the assimilation and acculturation processes described by ‘straight‐line theory’. This issue, as well as most others discussed, may also be salient for European countries experiencing immigration, especially those countries with troubled economies. 相似文献
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《Free radical research》2013,47(5):560-571
AbstractOn the basis of recent reports, we propose that impaired neurotrophin signaling (PI3k/Akt), low antioxidant levels, and generation of reactive oxygen species (ROS) conjointly participate in the progressive events responsible for the dopaminergic cell loss in Parkinson's disease (PD). In the present study we tried to target these deficits collectively through multiple neurotrophic factors (NTFs) support in the form of Olfactory Ensheathing Cell's Conditioned Media (OEC CM) using human SH-SY5Y neuroblastoma cell line exposed to 6 hydroxydopamine (6OHDA). 6OHDA exposure induced, oxidative stress-mediated apoptotic cell death viz. enhanced ROS generation, diffused cytosolic cytochrome c (cyt c), impaired Bcl-2: Bax levels along with decrease in GSH content. These changes were accompanied by loss in Akt phosphorylation and TH levels in SH-SY5Y cells. OEC CM significantly checked apoptotic cell death by preserving pAkt levels which coincided with enhanced GSH and suppressed oxidative injury. Functional integrity of OEC CM supported cells was evident by maintained tyrosine hydroxylase (TH) expression. Intercepting Akt signaling by specific inhibitor LY294002 blocked the protective effect. Taken together our findings provide important evidence that the key to protective effect of multiple NTF support via OEC CM is enhanced Akt survival signaling which promotes antioxidant defense leading to suppression of oxidative damage. 相似文献
305.
《Biotechnic & histochemistry》2013,88(3):175-176
In view of its probable wide applicability, it seems desirable to publish a note on a simple technic for the recognition with the microscope of the action of lipase. In brief, the method is to make an emulsion of neutral fat previously stained with a red Sudan stain, subject some of the emulsion to the action of the supposed lipase for an appropriate time and then examine with the microscope a recovered drop of the emulsion in a solution of Nile blue sulfate. It has long been known that Nile blue sulfate stains liquid neutral fats a reddish color and fatty acids blue. 相似文献
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《Bioorganic & medicinal chemistry letters》2014,24(24):5805-5813
The design and synthesis of a novel series of potent gamma secretase modulators is described. Exploration of various spacer groups between the triazole ring and the aromatic appendix in 2 has led to anilinotriazole 28, which combined high in vitro and in vivo potency with an acceptable drug-like profile. 相似文献
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Summary The effects have been studied of different salinities on the early stages of development of the Turbellarian Polyclad Stylochus mediterraneus Galleni. Optimal salinities are about 30%o. Variation away from this value increases the incidence of unhatched embryos, even if development is not greatly altered. On the contrary, at the highest tested salinities (50%o; 60%o) and the lowest (18%o), embryos are affected by great alterations in their morphology. 相似文献
310.