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Molecular Biology Reports - Among different pathological mechanisms, neuronal loss and neurogenesis impairment in the hippocampus play important roles in cognitive decline in Alzheimer’s...  相似文献   
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Molecular Biology Reports - Autophagy process is an important defense mechanism against intracellular infection. This process plays a critical role in limiting the development of Toxoplasma gondii....  相似文献   
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Molecular Biology Reports - Despite the advancements in primary brain tumour diagnoses and treatments, the mortality rate remains high, particularly in glioblastoma (GBM). Chemoresistance,...  相似文献   
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In the present study, radiation doses and cancer risks resulting from abdominopelvic radiotherapy planning computed tomography (RP-CT) and abdominopelvic diagnostic CT (DG-CT) examinations are compared. Two groups of patients who underwent abdominopelvic CT scans with RP-CT (n = 50) and DG-CT (n = 50) voluntarily participated in this study. The two groups of patients had approximately similar demographic features including mass, height, body mass index, sex, and age. Radiation dose parameters included CTDIvol, dose–length product, scan length, effective tube current, and pitch factor, all taken from the CT scanner console. The ImPACT software was used to calculate the patient-specific radiation doses. The risks of cancer incidence and mortality were estimated based on the BEIR VII report of the US National Research Council. In the RP-CT group, the mean ± standard deviation of cancer incidence risk for all cancers, leukemia, and all solid cancers was 621.58 ± 214.76, 101.59 ± 27.15, and 516.60 ± 189.01 cancers per 100,000 individuals, respectively, for male patients. For female patients, the corresponding risks were 742.71 ± 292.35, 74.26 ± 20.26, and 667.03 ± 275.67 cancers per 100,000 individuals, respectively. In contrast, for DG-CT cancer incidence risks were 470.22 ± 170.07, 78.23 ± 18.22, and 390.25 ± 152.82 cancers per 100,000 individuals for male patients, while they were 638.65 ± 232.93, 62.14 ± 13.74, and 575.73 ± 221.21 cancers per 100,000 individuals for female patients. Cancer incidence and mortality risks were greater for RP-CT than for DG-CT scans. It is concluded that the various protocols of abdominopelvic CT scans, especially the RP-CT scans, should be optimized with respect to the radiation doses associated with these scans.

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Cotton fibre quality is a multigenic trait. Genetic modification of different genes to achieve high quality fibre is difficult without knowing the mechanism lying behind genes interaction. Based on background knowledge an attempt to explore the potential structural interactions between Gossypium hirsutum Wlim5 domain1 and Gossypium hirsutum ACTIN-1 proteins was done in current study. Sequence features of the LIM domain1 of GhWlim5 protein were identified through multiple sequence alignment analysis, and a phylogenetic tree was built to identify evolutionary relationships between sequences. Conservation indicated the evolutionary importance of side chain residues and the presence of several aliphatic and/or bulky residues, which stabilize the protein core and facilitate packing of zinc fingers. The structures of GhWlim5 domain1 and GhACTIN-1 proteins were modelled and validated through computational methods. Validation of GhACTIN-1 and GhWlim5 domain1 structures indicated good structural quality with 99.7% and 100% of the favoured number of residues in allowed regions and Z-score, within the ranges of − 9.87 and − 4.17, respectively. Docking analysis indicated various possible modes of interaction between these two proteins with favourable binding affinities. Based on our strong binding interaction results between GhWlim5 domain1 and GhACTIN-1 proteins, we further investigated the role of over-expression of GhWlim5 by transformation in cotton plants under fibre specific promoter and transgenic plants displayed significant increases in fibre strength.

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Mehrabi  Fatemeh  Shamspur  Tayebeh  Sheibani  Hassan  Mostafavi  Ali  Mohamadi  Maryam  Hakimi  Hamid  Bahramabadi  Reza  Salari  Elham 《Biometals》2021,34(6):1237-1246
BioMetals - Trimethoprim and sulfamethoxazole are prescribed for a broad spectrum of bacteria. However, the use of these medicines is restricted due to the risk of microbial resistance in the body....  相似文献   
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目的:观察胎盘间充质干细胞对TGF-β1/Smad信号通路的调控作用,探讨胎盘间充质干细胞对烫伤愈合及瘢痕形成的影响。方法:构建小鼠烫伤模型,注射人胎盘间充质干细胞(hPMSCs),荧光显微镜观察小鼠创伤皮肤组织中hPMSCs细胞的存活情况;HE和Masson染色观察小鼠创伤皮肤的变化;Western blot检测观察创伤皮肤TGF-β1、p-Smad3、Smad7、α-SMA、collagen I、Collagen III蛋白表达变化。结果:注射hPMSCs细胞后,小鼠创伤面积逐渐减小,创伤愈合率逐渐增加;hPMSCs细胞分布在小鼠创伤皮肤组织中,存活状况较好。进一步研究发现烫伤模型组皮肤表层细胞受损脱落,真皮层组织疏松,毛囊、皮脂腺等附属器坏死,可见明显的毛细血管扩张,并伴有炎性细胞渗出,同时可见大量的成纤维细胞增生和胶原纤维形成;注射hPMSCs细胞治疗后,病理改变、纤维增生和胶原形成明显减轻;此外,烫伤模型组创伤皮肤组织中TGF-β1、p-Smad3表达明显上调,Smad7蛋白表达明显下调,α-SMA、collagen I、Collagen III表达明显上调。经hPMSCs细胞治疗后,TGF-β1、p-Smad3蛋白表达明显下调,Smad7蛋白表达明显上调,α-SMA、collagen I、Collagen III蛋白表达明显下调。结论:胎盘间充质干细胞可能通过抑制TGF-β1/Smad信号通路,发挥促进烫伤愈合且抑制瘢痕形成的作用。  相似文献   
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