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991.
Background aimsAssessing mesenchymal stromal cells (MSCs) after grafting is essential for understanding their migration and differentiation processes. The present study sought to evaluate via cellular magnetic resonance imaging (MRI) if transplantation route may have an effect on MSCs engrafting to fibrotic liver of rats.MethodsRat MSCs were prepared, labeled with superparamagnetic iron oxide and scanned with MRI. Labeled MSCs were transplanted via the portal vein or vena caudalis to rats with hepatic fibrosis. MRI was performed in vitro before and after transplantation. Histologic examination was performed. MRI scan and imaging parameter optimization in vitro and migration under in vivo conditions were demonstrated.ResultsStrong MRI susceptibility effects could be found on gradient echo-weighted, or T21-weighted, imaging sequences from 24 h after labeling to passage 4 of labeled MSCs in vitro. In vivo, MRI findings of the portal vein group indicated lower signal in liver on single shot fast spin echo-weighted, or T2-weighted, imaging and T21-weighted imaging sequences. The low liver MRI signal increased gradually from 0–3 h and decreased gradually from 3 h to 14 days post-transplantation. The distribution pattern of labeled MSCs in liver histologic sections was identical to that of MRI signal. It was difficult to find MSCs in tissues near the portal area on day 14 after transplantation; labeled MSCs appeared in fibrous tuberculum at the edge of the liver. No MRI signal change and a positive histologic examination were observed in the vena caudalis group.ConclusionsThe portal vein route seemed to be more beneficial than the vena caudalis on MSC migration to fibrotic liver of rats via MRI.  相似文献   
992.
Reviews in Environmental Science and Bio/Technology - In terms of energy resource recovery and environmental protection, the separation of U(VI) from aqueous solutions is vital. Adsorption and...  相似文献   
993.
994.
Long  Yuming  Zhuang  Kai  Ji  Zhonghai  Han  Yaru  Fei  Yanqing  Zheng  Wen  Song  Zhi  Yang  Heng 《Neurochemical research》2019,44(4):994-1004
Neurochemical Research - Epilepsy is a disorder of the brain characterized by an enduring predisposition to generate epileptic seizures. The glycolytic inhibitor 2-deoxy-d-glucose (2-DG) has been...  相似文献   
995.
Zheng  Yanhua  Liu  Junpeng  Zhuang  Jiajun  Dong  Xiaoyan  Yu  Miao  Li  Zhihui 《Neurochemical research》2021,46(4):878-887
Neurochemical Research - Parkinson’s disease (PD) is the second most prevalent neurodegenerative disorder. Long noncoding RNA (lncRNA) urothelial carcinoma-associated 1 (UCA1) has been...  相似文献   
996.
997.
峨眉拟单性木兰群落特征的初步研究   总被引:5,自引:0,他引:5  
对峨眉山峨眉拟单性木兰群落特征与种群结构的初步研究表明:1、蛾眉拟单性木兰及其群落分布局限,地形、土壤、气候条件较为特殊;2、该群落与中国云南和东部亚热带常绿阔叶林具有广泛的联系,并具各“顶极群落”的特征;3、峨眉拟单性木兰林的两个基木群丛为:(A)蛾眉拟单性木兰+四川人头茶+包石栎-箭竹-苔草群丛与 (B)黄心夜合+大叶新木姜子+峨眉拟单性木兰-箭竹-单芽狗脊群丛;4、人类和猴群的活动与干扰直接威胁着该种种群和群落的生存与稳定。  相似文献   
998.
峨眉山八角莲属植物的生态学与生物学特性研究   总被引:11,自引:2,他引:9  
本文对蛾眉山八角莲属植物的种类分布、生境和生物学特性进行了研究,结果表明,①蛾眉山八角莲属植物5种1变种,原始及变异类型分布集中;②种间垂直替代现象明显,对于阴湿环境及肥沃、酸性、多砾质土壤环境反应出一定程度的共同要求;③不同种类在生长节律、特性、花粉育性、花粉发芽条件以及自然繁殖能力等方面存在一定差别;④人工根插繁殖可提高本属植物的繁殖系数。  相似文献   
999.
The recent rise in atmospheric methane (CH4) concentrations accelerates climate change and offsets mitigation efforts. Although wetlands are the largest natural CH4 source, estimates of global wetland CH4 emissions vary widely among approaches taken by bottom-up (BU) process-based biogeochemical models and top-down (TD) atmospheric inversion methods. Here, we integrate in situ measurements, multi-model ensembles, and a machine learning upscaling product into the International Land Model Benchmarking system to examine the relationship between wetland CH4 emission estimates and model performance. We find that using better-performing models identified by observational constraints reduces the spread of wetland CH4 emission estimates by 62% and 39% for BU- and TD-based approaches, respectively. However, global BU and TD CH4 emission estimate discrepancies increased by about 15% (from 31 to 36 TgCH4 year−1) when the top 20% models were used, although we consider this result moderately uncertain given the unevenly distributed global observations. Our analyses demonstrate that model performance ranking is subject to benchmark selection due to large inter-site variability, highlighting the importance of expanding coverage of benchmark sites to diverse environmental conditions. We encourage future development of wetland CH4 models to move beyond static benchmarking and focus on evaluating site-specific and ecosystem-specific variabilities inferred from observations.  相似文献   
1000.
The soilborne bacterial pathogen Ralstonia solanacearum is one of the most destructive plant pathogens worldwide, and its infection process involves the manipulation of numerous plant cellular functions. In this work, we found that the R. solanacearum effector protein RipD partially suppressed different levels of plant immunity triggered by R. solanacearum elicitors, including specific responses triggered by pathogen-associated molecular patterns and secreted effectors. RipD localized in different subcellular compartments in plant cells, including vesicles, and its vesicular localization was enriched in cells undergoing R. solanacearum infection, suggesting that this specific localization may be particularly relevant during infection. Among RipD-interacting proteins, we identified plant vesicle-associated membrane proteins (VAMPs). We also found that overexpression of Arabidopsis thaliana VAMP721 and VAMP722 in Nicotiana benthamiana leaves promoted resistance to R. solanacearum, and this was abolished by the simultaneous expression of RipD, suggesting that RipD targets VAMPs to contribute to R. solanacearum virulence. Among proteins secreted in VAMP721/722-containing vesicles, CCOAOMT1 is an enzyme required for lignin biosynthesis, and mutation of CCOAOMT1 enhanced plant susceptibility to R. solanacearum. Altogether our results reveal the contribution of VAMPs to plant resistance against R. solanacearum and their targeting by a bacterial effector as a pathogen virulence strategy.  相似文献   
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