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排序方式: 共有466条查询结果,搜索用时 62 毫秒
461.
Preparative linear ion trap mass spectrometer for separation and collection of purified proteins and peptides in arrays using ion soft landing 总被引:3,自引:0,他引:3
Blake TA Ouyang Z Wiseman JM Takáts Z Guymon AJ Kothari S Cooks RG 《Analytical chemistry》2004,76(21):6293-6305
A preparative mass spectrometer for microarray fabrication is reported. The instrument includes an atmospheric pressure ionization source, a linear ion trap mass analyzer, an ion collection surface positioning system, and a surface loading chamber with independent vacuum pumping. It was designed for the production of protein arrays using the ion soft-landing technique to collect ions on a surface after separation by mass/charge ratio. Small microarrays have been prepared by isolating and soft landing individual protein or peptide ions after electrospray ionization of mixtures. The composition and purity of the separated materials has been confirmed using independent external mass spectrometric analysis of rinse solutions of the collected spots, either by the new method of electrosonic spray ionization MS or by nanospray ionization MS. The ability to retain bioactivity in the mass-selected and collected biomolecules has been demonstrated in particular cases. The reported instrument has also been characterized as an analytical mass spectrometer. 相似文献
462.
Chunxia Huang John Man Tak Chu Yan Liu Vivian Suk Wai Kwong Raymond Chuen Chung Chang Gordon Tin Chun Wong 《International journal of molecular sciences》2022,23(11)
Perioperative neurocognitive disorders are frequently observed in postoperative patients and previous reports have shown that pre-existing mild cognitive impairment with accumulated neuropathology may be a risk factor. Sevoflurane is a general anesthetic agent which is commonly used in clinical practice. However, the effects of sevoflurane in postoperative subjects are still controversial, as both neurotoxic or neuroprotective effects were reported. The purpose of this study is to investigate the effects of sevoflurane in 3 × Tg mice, a specific animal model with pre-existing Alzheimer’s disease neuropathology. 3 × Tg mice and wild-type mice were exposed to 2 h of sevoflurane respectively. Cognitive function, glutamate transporter expression, MAPK kinase pathways, and neuronal apoptosis were accessed on day 7 post-exposure. Our findings indicate that sevoflurane-induced cognitive deterioration in 3 × Tg mice, which was accompanied with the modulation of glutamate transporter, MAPK signaling, and neuronal apoptosis in the cortical and hippocampal regions. Meanwhile, no significant impact was observed in wild-type mice. Our results demonstrated that prolonged inhaled sevoflurane results in the exacerbation of neuronal and cognitive dysfunction which depends on the neuropathology background. 相似文献
463.
Wang Yuping Dong Qing Shi Shuying Zhang Xiaoqian Zhu Ze Guo Zhenfeng Chow Yuk Tak Wang Xinqiang Zhang Guanghui Zhu Luyi Xu Dong 《Journal of Materials Science: Materials in Electronics》2021,32(22):26359-26370
Journal of Materials Science: Materials in Electronics - Ba0.7Sr0.29La0.01TiO3 (BSLT) fibers with good crystallinity were prepared by the electrospinning method, and the flexible BSLT/PVDF... 相似文献
464.
Subin Kim Ki-Yeop Cho JunHwa Kwon Kiyeon Sim Dain Seok Hyunjong Tak Jinhyeon Jo KwangSup Eom 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(26):2207222
Lithium (Li) metal anodes (LMAs) are promising anode candidates for realizing high-energy-density batteries. However, the formation of unstable solid electrolyte interphase (SEI) layers on Li metal is harmful for stable Li cycling; hence, enhancing the physical/chemical properties of SEI layers is important for stabilizing LMAs. Herein, thiourea (TU, CH4N2S) is introduced as a new catalyzing agent for LiNO3 reduction to form robust inorganic-rich SEI layers containing abundant Li3N. Due to the unique molecular structure of TU, the TU molecules adsorb on the Cu electrode by forming Cu S bond and simultaneously form hydrogen bonding with other hydrogen bonds accepting species such as NO3− and TFSI− through its N H bonds, leading to their catalyzed reduction and hence the formation of inorganic-rich SEI layer with abundant Li3N, LiF, and Li2S/Li2S2. Particularly, this TU-modified SEI layer shows a lower film resistance and better uniformity compared to the electrochemically and naturally formed SEI layers, enabling planar Li growth without any other material treatments and hence improving the cyclic stability in Li/Cu half-cells and Li@Cu/LiFePO4 full-cells. 相似文献
465.
Spreadsheets are very common for information processing to support decision making by both professional developers and non-technical end users. Moreover, business intelligence and artificial intelligence are increasingly popular in the industry nowadays, where spreadsheets have been used as, or integrated into, intelligent or expert systems in various application domains. However, it has been repeatedly reported that faults often exist in operational spreadsheets, which could severely compromise the quality of conclusions and decisions based on the spreadsheets. With a view to systematically examining this problem via survey of existing work, we have conducted a comprehensive literature review on the quality issues and related techniques of spreadsheets over a 35.5-year period (from January 1987 to June 2022) for target journals and a 10.5-year period (from January 2012 to June 2022) for target conferences. Among other findings, two major ones are: (a) Spreadsheet quality is best addressed throughout the whole spreadsheet life cycle, rather than just focusing on a few specific stages of the life cycle. (b) Relatively more studies focus on spreadsheet testing and debugging (related to fault detection and removal) when compared with spreadsheet specification, modeling, and design (related to development). As prevention is better than cure, more research should be performed on the early stages of the spreadsheet life cycle. Enlightened by our comprehensive review, we have identified the major research gaps as well as highlighted key research directions for future work in the area. 相似文献
466.
Cho Yoonjeong Han Hyeon Tak Kim Tae-rahk Sohn Minn Park Young-Seo 《Food science and biotechnology》2023,32(4):497-506
Food Science and Biotechnology - The lactic acid bacteria, Lactococcus lactis subsp. lactis LM1185 was isolated from Hydrangea macrophylla. Strain LM1185 showed 50.5% of acid tolerance at pH 2.5... 相似文献