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排序方式: 共有517条查询结果,搜索用时 15 毫秒
511.
Al Borhan Bayazid Soo Ah Jeong Chae Won Park Da Hee Kim Beong Ou Lim 《Molecules (Basel, Switzerland)》2022,27(15)
Inflammatory bowel disease is characterized by a radical imbalance of inflammatory signaling pathways in the gastrointestinal tract, and it is categorized into two diseases, such as Crohn’s disease and ulcerative colitis. In this study, we investigated anti-inflammatory activities using fermented Curcuma that contains butyrate (FB). Nitric oxide production in RAW 264.7 cells and the expression of inducible nitric oxide synthase in the intestinal mucosa appears to be enhanced in active ulcerative colitis. Here, the cytotoxicity, physiological activity, and anti-inflammatory efficacy of FB in colitis animals were investigated. To verify the anti-inflammatory effect, this study was conducted using the dextran sulfate sodium (DSS)-induced colitis mice model. As a result, non-toxicity was confirmed, and anti-inflammatory effects were revealed by inducing a reduction of LPS-induced NO production. In the DSS-induced colitis, reduced weight was recovered and a decrease in inflammatory factors Ig-E and TNF-α in the mesenteric lymph node (MLN) and spleen was induced, and it was confirmed to help with the morphological remodeling of the intestine. In conclusion, this paper suggests that FB can help to alleviate intestinal inflammation and to improve the intestinal environment, with the help of morphological remodeling. 相似文献
512.
Jun-Yeong Yoon Yangjin Lee Dong-Gyu Kim Dong Gun Oh Jin Kyun Kim Linshuo Guo Jungcheol Kim Jeongheon Choe Kihyun Lee Hyeonsik Cheong Chae Un Kim Young Jai Choi Yanhang Ma Kwanpyo Kim 《Angewandte Chemie (International ed. in English)》2023,62(36):e202307102
Elemental phosphorus exhibits fascinating structural varieties and versatile properties. The unique nature of phosphorus bonds can lead to the formation of extremely complex structures, and detailed structural information on some phosphorus polymorphs is yet to be investigated. In this study, we investigated an unidentified crystalline phase of phosphorus, type-II red phosphorus (RP), by combining state-of-the-art structural characterization techniques. Electron diffraction tomography, atomic-resolution scanning transmission electron microscopy (STEM), powder X-ray diffraction, and Raman spectroscopy were concurrently used to elucidate the hidden structural motifs and their packing in type-II RP. Electron diffraction tomography, performed using individual crystalline nanowires, was used to identify a triclinic unit cell with volume of 5330 Å3, which is the largest unit cell for elemental phosphorus crystals up to now and contains approximately 250 phosphorus atoms. Atomic-resolution STEM imaging, which was performed along different crystal-zone axes, confirmed that the twisted wavy tubular motif is the basic building block of type-II RP. Our study discovered and presented a new variation of building blocks in phosphorus, and it provides insights to clarify the complexities observed in phosphorus as well as other relevant systems. 相似文献
513.
Dr. Sang Youn Chae Noyoung Yoon Dr. Oh shim Joo Prof. Eun Duck Park 《Angewandte Chemie (International ed. in English)》2023,62(7):e202215227
The electrochemical activation of CuInS2/MoSx for photoelectrochemical (PEC) H2 production was revealed for the first time through in operando Raman spectroscopy. During the activation process, the initial metallic MoSx phase was transformed to semiconducting MoSx, which facilitates charge carrier transfer between CuInS2 and MoSx. Ex situ X-ray photoelectron spectroscopy and Raman spectroscopy suggest the existence of MoO3 after the activation process. However, apart from contradicting these results, in operando Raman spectroscopy revealed some of the intermediate steps of the activation process. 相似文献
514.
Amey Nimkar Gil Bergman Elad Ballas Nophar Tubul Noam Levi Fyodor Malchik Idan Kukurayeve Munseok S. Chae Daniel Sharon Mikhael Levi Netanel Shpigel Guoxiu Wang Doron Aurbach 《Angewandte Chemie (International ed. in English)》2023,62(50):e202306904
The exploration of cathode and anode materials that enable reversible storage of mono and multivalent cations has driven extensive research on organic compounds. In this regard, polyimide (PI)-based electrodes have emerged as a promising avenue for the development of post-lithium energy storage systems. This review article provides a comprehensive summary of the syntheses, characterizations, and applications of PI compounds as electrode materials capable of hosting a wide range of cations. Furthermore, the review also delves into the advancements in PI based solid state batteries, PI-based separators, current collectors, and their effectiveness as polymeric binders. By highlighting the key findings in these areas, this review aims at contributing to the understanding and advancement of PI-based structures paving the way for the next generation of energy storage systems. 相似文献
515.
516.
Kyu Ho Chae 《Macromolecular rapid communications》1998,19(1):1-4
Two oxime-urethane derivatives, benzophenone oxime N-cyclohexylurethane (1 ) and dibenzophenone oxime N,N′-hexamethylenediurethane (2 ), were used as photobase generators. Photolysis of these derivatives results in the formation of amines which induce cross-linking of poly(glycidyl methacrylate) (PGMA) upon heating. The bifunctional derivative 2 is more efficient than the monofunctional derivative 1 in inducing thermal cross-linking of PGMA, with a maximum degree of insolubilization increasing up to ca. 90%. 相似文献
517.
Image recording material based on the polymeric photobase generator containing oxime‐urethane groups
Kyu Ho Chae Jung Choon Gwark Taihyun Chang 《Macromolecular rapid communications》2000,21(15):1007-1012
A polymeric photobase generator containing oxime‐urethane groups was prepared from copolymerization of MMA with N‐[4‐(benzophenoneoximino‐carbonylamino)phenyl]maleimide, a maleimide monomer containing oxime‐urethane group, and its properties as an image recording material were studied. The irradiation of this copolymer with UV light dissociates the urethane linkage to result in the formation of aromatic amino groups, which can be developed by the diazo‐coupling reaction. Various colors could be developed depending on the phenolic coupling reagents as the developer. 相似文献