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Yang Su-Rong Sun Huan-Xin Hu Zhen-Zhen Wang Si-Heng Sun Hui Xue Yin-Jia Ye Chen-Bo 《Sleep and biological rhythms》2017,15(1):57-65
Sleep and Biological Rhythms - Chronic sleep deprivation (SD) is an overwhelming problem in young students. Firstly, we investigated whether different levels of pre-training SD had effects on... 相似文献
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Joong Kyu Kim Mark Klinger Jonathan Benjamin Yuanyuan Xiao David J. Erle Dan R. Littman Nigel Killeen 《PloS one》2009,4(8)
Signaling through the T cell antigen receptor (TCR) is important for the homeostasis of naïve and memory CD4+ T cells. The significance of TCR signaling in regulatory T (Treg) cells has not been systematically addressed. Using an Ox40-cre allele that is prominently expressed in Treg cells, and a conditional null allele of the gene encoding p56Lck, we have examined the importance of TCR signaling in Treg cells. Inactivation of p56Lck resulted in abnormal Treg homeostasis characterized by impaired turnover, preferential redistribution to the lymph nodes, loss of suppressive function, and striking changes in gene expression. Abnormal Treg cell homeostasis and function did not reflect the involvement of p56Lck in CD4 function because these effects were not observed when CD4 expression was inactivated by Ox40-cre.The results make clear multiple aspects of Treg cell homeostasis and phenotype that are dependent on a sustained capacity to signal through the TCR. 相似文献
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The molecular mechanism that controls the proliferation and differentiation of prostate epithelial cells is currently unknown. We previously identified a 44-kDa protein (p44/wdr77) as an androgen receptor-interacting protein that regulates a set of androgen receptor target genes in prostate epithelial cells and prostate cancer. In this study, we found that p44 localizes in the cytoplasm of prostate epithelial cells at the early stage of prostate development when cells are proliferating, and its nuclear translocation is associated with cellular and functional differentiation in adult prostate tissue. We further demonstrated that cytoplasmic p44 protein is essential for proliferation of prostate epithelial cells, whereas nuclear p44 is required for cell differentiation and prostate- specific protein secretion. These studies suggest a novel mechanism by which proliferation and differentiation of prostate epithelial cells are controlled by p44’s location in the cell. 相似文献
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皮肤作为人体最大器官覆盖于全身,能阻挡有害物质的侵入,保护人体内环境稳态,参与人体代谢过程。皮肤损伤、炎症和纤维化等,都会导致皮肤屏障功能的减退,影响正常的生命活动。溶血磷脂酸(lysophosphatidic acid,LPA)是十分活跃的磷脂信号分子,参与多种生理和病理生理过程。LPA是维持体内平衡所必需的生物活性脂质介质,在皮肤中通过不同的信号通路发挥多功能磷脂信使作用。本文综述了皮肤中溶血磷脂酸受体(lysophosphatidic acid receptor,LPA1-6)及其细胞信号通路的作用及机制,综述了LPA在皮肤创面愈合、皮肤瘢痕、皮肤黑色素瘤、硬皮病、皮肤瘙痒、过敏性皮炎、皮肤屏障、皮肤疼痛,皮肤毛发生长中的作用及分子机制,有助于了解LPA在皮肤中的生理和病理生理作用。深入研究LPA的作用机制将有助于挖掘其在皮肤治疗中的作用,开发以LPA为靶点的药物。 相似文献
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Many animals exhibit different behaviors in different seasons. The photoperiod can have effects on migration, breeding, fur growth, and other processes. The cyclic growth of the fur and feathers of some species of mammals and birds, respectively, is stimulated by the photoperiod as a result of hormone-dependent regulation of the nervous system. To further examine this phenomenon, we evaluated the Arbas Cashmere goat (Capra hircus), a species that is often used in this type of research. The goats were exposed to an experimentally controlled short photoperiod to study the regulation of cyclic cashmere growth. Exposure to a short photoperiod extended the anagen phase of the Cashmere goat hair follicle to increase cashmere production. Assessments of tissue sections indicated that the short photoperiod significantly induced cashmere growth. This conclusion was supported by a comparison of the differences in gene expression between the short photoperiod and natural conditions using gene chip technology. Using the gene chip data, we identified genes that showed altered expression under the short photoperiod compared to natural conditions, and these genes were found to be involved in the biological processes of hair follicle growth, structural composition of the hair follicle, and the morphogenesis of the surrounding skin appendages. Knowledge about differences in the expression of these genes as well as their functions and periodic regulation patterns increases our understanding of Cashmere goat hair follicle growth. This study also provides preliminary data that may be useful for the development of an artificial method to improve cashmere production by controlling the light cycle, which has practical significance for livestock breeding. 相似文献
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Fertilized eggs of Sebastes schlegelii, Sebastes pachycephalus and Sebastes hubbsi are morphologically similar under stereomicroscope. However, under the scanning electron microscope, significant differences in the ultrastructures of the egg surface among the three species were observed, and herein, a taxonomic key was proposed for future applications. A clustering analysis based on the ultrastructures of the egg surface and the diameter of the oil globule suggested that among the three species, S. hubbsi and S. pachycephalus were more genetically similar, while S. schlegelii had diverged earlier. The results agree with the conclusions drawn from morphological and molecular analyses on adult samples of the same species. 相似文献