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排序方式: 共有4404条查询结果,搜索用时 15 毫秒
81.
Marchaim D Chopra T Bogan C Bheemreddy S Sengstock D Jagarlamudi R Malani A Lemanek L Moshos J Lephart PR Ku K Hasan A Lee J Khandker N Blunden C Geffert SF Moody M Hiro R Wang Y Ahmad F Mohammadi T Faruque O Patel D Pogue JM Hayakawa K Dhar S Kaye KS 《American journal of infection control》2012,40(8):760-765
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Min-Chi Ku Susanne A. Wolf Dorota Respondek Vitali Matyash Andreas Pohlmann Sonia Waiczies Helmar Waiczies Thoralf Niendorf Michael Synowitz Rainer Glass Helmut Kettenmann 《Acta neuropathologica》2013,125(4):609-620
High-grade gliomas are the most common primary brain tumors. Their malignancy is promoted by the complex crosstalk between different cell types in the central nervous system. Microglia/brain macrophages infiltrate high-grade gliomas and contribute to their progression. To identify factors that mediate the attraction of microglia/macrophages to malignant brain tumors, we established a glioma cell encapsulation model that was applied in vivo. Mouse GL261 glioma cell line and human high-grade glioma cells were seeded into hollow fibers (HF) that allow the passage of soluble molecules but not cells. The glioma cell containing HF were implanted into one brain hemisphere and simultaneously HF with non-transformed fibroblasts (controls) were introduced into the contralateral hemisphere. Implanted mouse and human glioma- but not fibroblast-containing HF attracted microglia and up-regulated immunoreactivity for GFAP, which is a marker of astrogliosis. In this study, we identified GDNF as an important factor for microglial attraction: (1) GL261 and human glioma cells secret GDNF, (2) reduced GDNF production by siRNA in GL261 in mouse glioma cells diminished attraction of microglia, (3) over-expression of GDNF in fibroblasts promoted microglia attraction in our HF assay. In vitro migration assays also showed that GDNF is a strong chemoattractant for microglia. While GDNF release from human or mouse glioma had a profound effect on microglial attraction, the glioma-induced astrogliosis was not affected. Finally, we could show that injection of GL261 mouse glioma cells with GDNF knockdown by shRNA into mouse brains resulted in reduced tumor expansion and improved survival as compared to injection of control cells. 相似文献
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Anush Mnoyan Myeongil Choi Dong Hyun Kim Bon-Jun Ku Hyunjoung Kim Kyung Jin Lee Ahmed S. Yasin Sungchan Nam Kyubock Lee 《RSC advances》2020,10(69):42432
Solar-to-steam generation characterized by nanostructured photothermal materials and interfacial heating is developed based on various carbon nanostructures such as graphene, reduced graphene oxide, CNT, or their combinations. However, multiple and sophisticated synthetic steps are required to generate macroscopic porosity in photothermal devices for the efficient mass transport of water and generated steam. Additionally, the fabrication of photothermal layers on a practical scale constitutes the main hurdle for real applications toward solar-driven desalination. Herein, we report on the development of highly efficient photothermal layers with a commercially available low-cost material, activated carbon (AC), by using facile filtration and spray coating methods, which lead to the generation of intraparticle porous structure without any additional processing. The AC-based photothermal layers generated 1.17 kg m−2 h−1 of steam under 1 sun, and 4.7 wt% of polyethyleneimine coating on AC enhanced steam generation by 8.5% under 1 sun, corresponding to 1.27 kg m−2 h−1 of the water evaporation rate and 85.66% of the photothermal conversion efficiency. This was due to improvements in light absorption and water uptake properties with the additional advantage of mechanical robustness. The outdoor solar-to-steam generation test with the spray-coated A4-sized photothermal layer in conjunction with the desalination test demonstrated the potential for practical desalination application with upscalability.Highly efficient photothermal layers were developed based on a commercially available low-cost material, activated carbon, which demonstrates the potential for practical desalination application with upscalability. 相似文献
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He Ji Fu Jiayu Zhao Wei Ren Chuan Liu Ping Chen Lu Li Dan Tang Lu Zhou Lequn Zhang Yixuan Ma Xinran Zhang Gaoqi Li Nan Fan Dongsheng 《Journal of neurology》2022,269(3):1447-1455
Journal of Neurology - Exploration of hypermetabolism in amyotrophic lateral sclerosis (ALS) with different ethnicities is needed to understand its metabolic implications for clinical management.... 相似文献
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The phase-variable allele of the pilus glycosylation gene pglA is not strongly associated with strains of Neisseria gonorrhoeae isolated from patients with disseminated gonococcal infection 下载免费PDF全文
Power PM Ku SC Rutter K Warren MJ Limnios EA Tapsall JW Jennings MP 《Infection and immunity》2007,75(6):3202-3204
The Neisseria gonorrhoeae pglA gene has two alleles, one of which is phase variable. A previous study reported that all disseminated gonococcal infection (DGI) isolates contained the phase-variable allele and proposed a causal link. In the present study of 81 strains no absolute correlation between DGI and the phase-variable pglA allele was observed. 相似文献