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排序方式: 共有1894条查询结果,搜索用时 31 毫秒
941.
特发性肺纤维化(IPF)是一种严重影响肺通气与换气功能的下呼吸道慢性疾病,其发病机理目前尚不明确,表现为异常的间质炎症和纤维化,以及肺泡结构的破坏。而Ⅱ型肺泡上皮细胞(ATⅡ)作为维持肺结构和功能的关键细胞,在肺部纤维化的发生和发展中极其重要。在IPF中,各种原因所致的ATⅡ的受损和衰老凋亡,可能是纤维化发生的是始动因素。而在这之后,关于临时基质的形成、成纤维细胞的聚集、激活以及间质-上皮转化的过程,异常的ATⅡ也参与其中,并发挥着重要的作用。 相似文献
942.
Lou Yijun Liu Kaihui He Daihai Gao Daozhou Ruan Shigui 《Journal of mathematical biology》2019,78(7):2259-2288
Journal of Mathematical Biology - Diapause, a period of arrested development caused by adverse environmental conditions, serves as a key survival mechanism for insects and other invertebrate... 相似文献
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944.
The nonspecific interaction between lead ions and bovine serum albumin (BSA) was studied by the calorimetric technique. According
to thermodynamic parameters calculated from titration curves, it can be seen that the increase of intermolecular bond energies
and decrease of disorder in the system were accompanied by a binding process. This kind of binding is the reaction “driven
by enthalpy.” Furthermore, the denatured BSA has more binding sites and more changes in enthalpy and entropy than the native
BSA because the unfolded chain of denatured BSA could adapt itself to the binding reaction with lead ions more easily. 相似文献
945.
Toll-like receptors (TLRs) mediate immune responses via the recognition of pathogen-associated molecular patterns (PAMPs), thus playing important roles in host defense. Among the chicken (Ch) TLR family, ChTLR3 and 7 have been shown to recognize viral RNA. In our earlier studies, we have reported polymorphisms of TLR1, 2, 4, 5, 15 and 21. In the present study, we amplified TLR3 and 7 genes from different chicken breeds and analyzed their sequences. We identified 7 amino acid polymorphism sites in ChTLR3 with 6 outer part sites and 1 inner part site, and 4 amino acid polymorphism sites in ChTLR7 with 3 outer part sites and 1 inner part site. These results demonstrate that ChTLR genes are polymorphic among different chicken breeds, suggesting a varied resistance across numerous chicken breeds. This information might help improve chicken health by breeding and vaccination. 相似文献
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Zhao XY Liang SF Yao SH Ma FX Hu ZG Yan F Yuan Z Ruan XZ Yang HS Zhou Q Wei YQ 《Biochemical and biophysical research communications》2007,361(1):74-78
Xenopus laevis has recently been determined as a novel study platform of gene function. In this study, we cloned Xenopus DRR1 (xDRR1), which is homologous to human down-regulated in renal carcinoma (DRR1) gene. Bioinformatics analysis for DRR1 indicated that xDRR1 shared 74% identity with human DRR1 and 66% with mouse DRR1, and the phlogenetic tree of DRR1 protein was summarized. The xDRR1 gene locates in nuclei determined by transfecting A549 cells with the recombinant plasmid pEGFP-N1/xDRR1. RT-PCR analysis revealed that xDRR1 gene was expressed in all stages of early embryo development and all kinds of detected tissues, and whole-mount in situ hybridization showed xDRR1 was mainly present along ectoderm and mesoderm. Furthermore, xDRR1 expression could suppress A549 cell growth by transfecting with plasmid pcDNA3.1(+)/xDRR1. xDRR1 probably plays important roles involving in cell growth regulation and Xenopus embryo development. 相似文献
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950.
Lijuan Xing Guangsen Shi Haibin Ruan Xiwen Gu Zhiwei Liu Xi Wu Xiang Gao Ying Xu 《The EMBO journal》2010,29(8):1389-1400
The circadian clock has a central role in physiological adaption and anticipation of day/night changes. In a genetic screen for novel regulators of circadian rhythms, we found that mice lacking MAGED1 (Melanoma Antigen Family D1) exhibit a shortened period and altered rest–activity bouts. These circadian phenotypes are proposed to be caused by a direct effect on the core molecular clock network that reduces the robustness of the circadian clock. We provide in vitro and in vivo evidence indicating that MAGED1 binds to RORα to bring about positive and negative effects on core clock genes of Bmal1, Rev‐erbα and E4bp4 expression through the Rev‐Erbα/ROR responsive elements (RORE). Maged1 is a non‐rhythmic gene that, by binding RORα in non‐circadian way, enhances rhythmic input and buffers the circadian system from irrelevant, perturbing stimuli or noise. We have thus identified and defined a novel circadian regulator, Maged1, which is indispensable for the robustness of the circadian clock to better serve the organism. 相似文献