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991.
Miao J Choi SE Seok SM Yang L Zuercher WJ Xu Y Willson TM Xu HE Kemper JK 《Molecular endocrinology (Baltimore, Md.)》2011,25(7):1159-1169
992.
Nina Safar-Hermann Mohammed N. Ismail Han Sun Choi Erich Mstl Elmar Bamberg 《Zoo biology》1987,6(2):189-193
Estrogen concentration in feces was investigated in five different herbivorous species of zoo animals. Using a nonspecific estrogen radioimmunoassay, in four species (red buffalo, yak, Grevy's zebra, and Nubian ibex) pregnancy was revealed by measuring estrogen concentration in feces. In hippopotamus, the levels of fecal estrogens were not different between pregnant and nonpregnant animals. 相似文献
993.
Zhang L Hosoi M Fukuzawa M Sun H Rawlings RR Weight FF 《The Journal of biological chemistry》2002,277(48):46256-46264
Ethanol can potentiate serotonin type 3 (5-HT(3)) receptor-mediated responses in various neurons and in cells expressing 5-HT(3A) receptors. However, the molecular basis for alcohol modulation of 5-HT(3) receptor function has not been determined. Here we report that point mutations of the arginine at amino acid 222 in the N-terminal domain of the 5-HT(3A) receptor can alter the EC(50) value of the 5-HT concentration-response curve. Some point mutations at amino acid 222 resulted in spontaneous opening of the 5-HT(3A) receptor channel and an inward current activated by ethanol in the absence of agonist. Among these mutant receptors, the amplitude of the current activated by ethanol in the absence of agonist was correlated with the amplitude of the current resulting from spontaneous channel openings, suggesting that the sensitivity of the receptor to ethanol in the absence of agonist is, at least in part, dependent on the preexisting conformational equilibrium of the receptor protein. On the other hand, point mutations that conferred greater sensitivity to ethanol potentiation of agonist-activated responses were less sensitive or insensitive to ethanol in the absence of agonist. For these receptors, the magnitude of the potentiation of agonist-activated responses by ethanol was inversely correlated with the EC(50) values of the 5-HT concentration-response curves, suggesting that these mutations may modulate ethanol sensitivity of the receptor by altering the EC(50) value of the receptor. Thus, distinct molecular processes may determine the sensitivity of 5-HT(3A) receptors to ethanol in the absence and presence of agonist. 相似文献
994.
995.
Qiu-Hong Wu Yong-Xing Chen Sheng-Hui Zhou Lin Fu Jiao-Jiao Chen Yao Xiao Dong Zhang Shu-Hong Ouyang Xiao-Jie Zhao Yu Cui De-Yun Zhang Yong Liang Zhen-Zhong Wang Jing-Zhong Xie Jin-Xia Qin Guo-Xin Wang De-Lin Li Yin-Lian Huang Mei-Hua Yu Ping Lu Li-Li Wang Ling Wang Hao Wang Chen Dang Jie Li Yan Zhang Hui-Ru Peng Cheng-Guo Yuan Ming-Shan You Qi-Xin Sun Ji-Rui Wang Li-Xin Wang Ming-Cheng Luo Jun Han Zhi-Yong Liu 《PloS one》2015,10(2)
High-density genetic linkage maps are necessary for precisely mapping quantitative trait loci (QTLs) controlling grain shape and size in wheat. By applying the Infinium iSelect 9K SNP assay, we have constructed a high-density genetic linkage map with 269 F 8 recombinant inbred lines (RILs) developed between a Chinese cornerstone wheat breeding parental line Yanda1817 and a high-yielding line Beinong6. The map contains 2431 SNPs and 128 SSR & EST-SSR markers in a total coverage of 3213.2 cM with an average interval of 1.26 cM per marker. Eighty-eight QTLs for thousand-grain weight (TGW), grain length (GL), grain width (GW) and grain thickness (GT) were detected in nine ecological environments (Beijing, Shijiazhuang and Kaifeng) during five years between 2010–2014 by inclusive composite interval mapping (ICIM) (LOD≥2.5). Among which, 17 QTLs for TGW were mapped on chromosomes 1A, 1B, 2A, 2B, 3A, 3B, 3D, 4A, 4D, 5A, 5B and 6B with phenotypic variations ranging from 2.62% to 12.08%. Four stable QTLs for TGW could be detected in five and seven environments, respectively. Thirty-two QTLs for GL were mapped on chromosomes 1B, 1D, 2A, 2B, 2D, 3B, 3D, 4A, 4B, 4D, 5A, 5B, 6B, 7A and 7B, with phenotypic variations ranging from 2.62% to 44.39%. QGl.cau-2A.2 can be detected in all the environments with the largest phenotypic variations, indicating that it is a major and stable QTL. For GW, 12 QTLs were identified with phenotypic variations range from 3.69% to 12.30%. We found 27 QTLs for GT with phenotypic variations ranged from 2.55% to 36.42%. In particular, QTL QGt.cau-5A.1 with phenotypic variations of 6.82–23.59% was detected in all the nine environments. Moreover, pleiotropic effects were detected for several QTL loci responsible for grain shape and size that could serve as target regions for fine mapping and marker assisted selection in wheat breeding programs. 相似文献
996.
Bradford assay is one of the most common methods for measuring protein concentrations. However, some pharmaceutical excipients, such as detergents, interfere with Bradford assay even at low concentrations. Protein precipitation can be used to overcome sample incompatibility with protein quantitation. But the rate of protein recovery caused by acetone precipitation is only about 70%. In this study, we found that sucrose not only could increase the rate of protein recovery after 1 h acetone precipitation, but also did not interfere with Bradford assay. So we developed a method for rapid protein quantitation in protein drugs even if they contained interfering substances. 相似文献
997.
Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a positive relationship between pollen size and style length.Five floral traits were observed to be correlated among42 bumblebee-pollinated Pedicularis species(Orobanchaceae) in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin's functional hypothesis between pollen size and stigma depth. 相似文献
998.
Xin Fu Jun Xiao Yuning Wei Sheng Li Yan Liu Jie Yin Kun Sun Hao Sun Huating Wang Zongkang Zhang Bao-Ting Zhang Chun Sheng Hongyan Wang Ping Hu 《Cell research》2015,25(6):655-673
Muscle stem cells (MuSCs, satellite cells) are the major contributor to muscle regeneration. Like most adult stem cells, long-term expansion of MuSCs in vitro is difficult. The in vivo muscle regeneration abilities of MuSCs are quickly lost after culturing in vitro, which prevents the potential applications of MuSCs in cell-based therapies. Here, we establish a system to serially expand MuSCs in vitro for over 20 passages by mimicking the endogenous microenvironment. We identified that the combination of four pro-inflammatory cytokines, IL-1α, IL-13, TNF-α, and IFN-γ, secreted by T cells was able to stimulate MuSC proliferation in vivo upon injury and promote serial expansion of MuSCs in vitro. The expanded MuSCs can replenish the endogenous stem cell pool and are capable of repairing multiple rounds of muscle injuries in vivo after a single transplantation. The establishment of the in vitro system provides us a powerful method to expand functional MuSCs to repair muscle injuries. 相似文献
999.
Zhang Yong Xia Qin Jian Sun Hua Yang Ming Xia Zhang Ru Ban Ge Lin Xu Ya Ping Wu Le Xin Wang Yi Feng Du 《PloS one》2015,10(6)
Background and Objectives
Carotid artery stenting (CAS) is an important therapeutic strategy for patients with carotid artery stenosis. However, the potential influence of CAS on cognitive function in patients with carotid artery stenosis and cerebral lacunar infarction has not been determined. This study investigated changes in cognitive function associated with CAS and the factors related to these changes.Methods
This prospective cohort study comprised 579 Chinese patients with cerebral lacunar infarction and carotid artery stenosis for whom CAS was indicated, and a matched control group of 552 healthy individuals. Cognitive function before CAS and at scheduled intervals from 6 months to 3 years was assessed with instruments that included the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scale. Potential factors that might affect cognitive function were analyzed via logistic regression.Results
The MMSE and MoCA scores of the patients before CAS were significantly lower than that of the control subjects. These scores were significantly higher 6 months after CAS and sustained or increased throughout the 3-year follow-up. Also significantly improved after CAS from baseline were scores for an alternating trail test, cube copying, clock-drawing, attention, and delayed recall in an auditory-verbal learning test. Logistic regression analyses showed that age greater than 65 y, little education, diabetes, and hypertension were independent risk factors for deteriorated MoCA scores 3 years after CAS.Conclusion
CAS was associated with significantly improved cognitive function in cerebral lacunar infarction patients with severe stenosis. 相似文献1000.