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111.
The effect of reduced balanced protein (RP) diet in the F0 and F1 generation of broiler breeders on the learning ability and memory retention of the F2 generation was investigated by means of a reward v. no reward discrimination T-maze test. There were two treatments for the F0 generation: control (C) group, reared on standard commercial diets, and reduced balanced protein (RP) group, fed with RP diets (25% reduction in CP and amino acids). The female F0-progeny of each treatment was again separated into the two dietary treatments, resulting in four treatments for the F1 generation: C/C, C/RP, RP/C and RP/RP (breeder feed in F0/F1 generation). The RP diets fed breeders received on average 10% more feed than C diets fed breeders to achieve a similar target BW. The F2 generation was composed of four treatments coming from the female F1-progeny of the four treatments and were all fed with C diet (namely C/C/C, C/RP/C, RP/C/C and RP/RP/C). All four F2 generation groups were able to complete the T-maze learning test with a slight difference in success rate but a significant difference within groups was observed regarding the time needed to complete the test. In general, the RP/RP/C group needed more time for completing the test compared with the other three groups and the shortest time was recorded for the RP/C/C group. At similar ages, breeders with early learning experience spent significantly less time in completing the test compared with unexperienced breeders. Long-term memory retention was observed in all four groups whereas the learning ability in solving the test decreased with age. It took longer for the breeders to complete the test at older ages. In conclusion, under our experimental conditions, the RP dietary treatment in previous generations had no influence on the T-maze learning ability and memory retention of broiler breeders of the third generation, although it might have effects on the working performance in the T-maze learning test of F2 generation breeders.  相似文献   
112.
To describe the effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on serum uric acid (SUA) in patients with type 2 diabetes mellitus (T2DM). PubMed, EMBASE, and CENTRAL were searched for randomized controlled trials of SGLT2 inhibitors in patients with T2DM up to Aug 10, 2017, without language or date restrictions. Thirty-one studies totaling 13,650 patients were included. SGLT2 inhibitors significantly decreased SUA levels compared with placebo, canagliflozin WMD –37.02?μmol/L, 95% CI [–38.41, –35.63], dapagliflozin WMD –38.05?μmol/L, 95% CI [–44.47, –31.62], empagliflozin WMD –42.07?μmol/L, 95% CI [–46.27, –37.86]. The drug class effect of SUA reduction suggesting SGLT2 inhibitors might be beneficial for diabetic patients with hyperuricemia.  相似文献   
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A multi-population biofilm model for completely autotrophic nitrogen removal was developed and implemented in the simulation program AQUASIM to corroborate the concept of a redox-stratification controlled biofilm (ReSCoBi). The model considers both counter- and co-diffusion biofilm geometries. In the counter-diffusion biofilm, oxygen is supplied through a gas-permeable membrane that supports the biofilm while ammonia (NH(4)(+)) is supplied from the bulk liquid. On the contrary, in the co-diffusion biofilm, both oxygen and NH(4)(+) are supplied from the bulk liquid. Results of the model revealed a clear stratification of microbial activities in both of the biofilms, the resulting chemical profiles, and the obvious effect of the relative surface loadings of oxygen and NH(4)(+) (J(O(2))/J(NH(4)(+))) on the reactor performances. Steady-state biofilm thickness had a significant but different effect on T-N removal for co- and counter-diffusion biofilms: the removal efficiency in the counter-diffusion biofilm geometry was superior to that in the co-diffusion counterpart, within the range of 450-1,400 microm; however, the efficiency deteriorated with a further increase in biofilm thickness, probably because of diffusion limitation of NH(4)(+). Under conditions of oxygen excess (J(O(2))/J(NH(4)(+)) > 3.98), almost all NH(4)(+) was consumed by aerobic ammonia oxidation in the co-diffusion biofilm, leading to poor performance, while in the counter-diffusion biofilm, T-N removal efficiency was maintained because of the physical location of anaerobic ammonium oxidizers near the bulk liquid. These results clearly reveal that counter-diffusion biofilms have a wider application range for autotrophic T-N removal than co-diffusion biofilms.  相似文献   
116.
Little is known about the role of p38MAPK in human adipocyte differentiation. Here we showed that p38MAPK activity increases during human preadipocytes differentiation. Pharmacological inhibition of p38MAPK during adipocyte differentiation of primary human preadipocytes markedly reduced triglycerides accumulation and adipocyte markers expression. Cell cycle arrest or proliferation was not affected by p38MAPK inhibition. Although induction of C/EBPbeta was not altered by the p38MAPK inhibitor, its phosphorylation on Threonine(188) was decreased as well as PPARgamma expression. These results indicate that p38MAPK plays a positive role in human adipogenesis through regulation of C/EBPbeta and PPARgamma factors.  相似文献   
117.
Na,K-ATPase is a crucial enzyme for ion homeostasis in human tissues. Different isozymes are produced by assembly of four alpha- and three beta-subunits. The expression of the alpha3/beta1 isozyme is confined to brain and heart. Its heterologous production has so far never been attempted in a lower eukaryote. In this work we explored whether the methylotrophic yeast Pichia pastoris is capable of expressing the alpha3/beta1 isoform of human Na,K-ATPase. cDNAs encoding the alpha(3) and the beta(1)-subunits were cloned under the control of the inducible promoter of Pichia pastoris alcohol oxidase 1. Pichia pastoris could express the single alpha3- and beta1-subunits and even coexpress them after methanol induction. beta1-subunit was produced as a major 44-kDa glycosylated polypeptide and alpha3 as a 110-kDa unglycosylated polypeptide. Expression at the plasma membrane was limited in shaking flask cultures but by cultivating P. pastoris cells in a fermenter there was a 10-fold increase of the number of ouabain binding sites per cell. The exported enzyme was estimated to be about 0.230 mg L(-1) at the end of a bioreactor run. Na,K-ATPase proved active and the dissociation constant of the recombinant enzyme-ouabain interaction was determined.  相似文献   
118.
摘要 目的:探讨与分析吻合皮下静脉的带蒂皮瓣修复四肢皮肤软组织缺损的效果。方法:选择2018年12月到2021年12月在本院创伤造成的四肢皮肤软组织缺损60例患者作为研究对象,将其随机分为吻合皮下静脉带蒂皮瓣组与传统带蒂皮瓣组各30例。吻合皮下静脉带蒂皮瓣组给予吻合皮下静脉的带蒂皮瓣修复治疗,传统带蒂皮瓣组给予常规直接覆盖创面修复治疗。结果:所有患者都顺利完成手术,吻合皮下静脉带蒂皮瓣组围手术指标时间均较传统带蒂皮瓣组少(P<0.05)。吻合皮下静脉带蒂皮瓣组术后3个月的总有效率为96.7 %,高于传统带蒂皮瓣组的76.7 %(P<0.05)。吻合皮下静脉带蒂皮瓣组术后3个月的并发症发生率较传统带蒂皮瓣组低(P<0.05)。吻合皮下静脉带蒂皮瓣组术后6个月的感觉功能恢复情况好于传统带蒂皮瓣组(P<0.05)。结论:吻合皮下静脉的带蒂皮瓣能促进患者的创面愈合,提高治疗效果,减少并发症,加快恢复患者的四肢皮肤软组织缺损。  相似文献   
119.
岩溶区水生生态系统微藻的生物碳泵效应   总被引:2,自引:0,他引:2  
严壮  汪夏雨  李为  余龙江 《微生物学报》2019,59(6):1012-1025
微藻在水生生态系统的碳固定中扮演重要角色。本文综述了岩溶区水生生态系统生物碳泵的提出、岩溶区微藻生物碳泵作用、影响微藻固碳的主要环境因素以及岩溶区微藻固碳的研究进展,并提出了亟待解决的关键科学问题,为深入研究岩溶区水生生态系统微藻固碳能力及生物碳泵机制、科学认识岩溶生态系统的碳汇潜力、丰富和完善岩溶碳循环理论提供参考。  相似文献   
120.
Capsaicinoids are reported to have a bunch of promising pharmacological activities, among them antibacterial effects against various strains of bacteria. In this study the effect on efflux pumps of mycobacteria was investigated. The importance of efflux pumps, and the inhibition of these, is rising due to their involvement in antibiotic resistance development. In order to draw structure and activity relationships we tested natural and synthetical capsaicinoids as well as synthetical capsinoids. In an accumulation assay these compounds were evaluated for their ability to accumulate ethidium bromide into mycobacterial cells, a well-known substrate for efflux pumps. Capsaicin and dihydrocapsaicin, the two most abundant capsaicinoids in Capsicum species, proved to be superior efflux pump inhibitors compared to the standard verapamil. A dilution series showed dose dependency of both compounds. The compound class of less pungent capsinoids qualified for further investigation as antibacterials against Mycobacterium smegmatis.  相似文献   
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