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141.
Drynariae Rhizoma (DR), a traditional Korean herbal medicine, has long been used for vital energy and to strengthen health in Korea. However, it is still unclear how DR has the effects in experimental models. We examined the immune-enhancing effect of DR in mice using the forced swimming test (FST) and in vitro tests with peritoneal macrophages. After daily oral administration of DR, blood biochemical parameters related to fatigue were measured after the FST. The immobility time in the FST was significantly decreased in the DR-treated group (100 mg/kg) on the 3th days. DR (10 and 100 mg/kg) treatment significantly decreased creatine kinase and lactic dehydrogenase levels, which are accurate indicators of muscle damage. Further, we examined how DR regulates nitric oxide (NO) production and tumor necrosis factor alpha (TNF-alpha) production and in mouse peritoneal macrophages. When DR was used in combination with recombinant interferon-gamma (rIFN-gamma), there were noticeable cooperative productions of NO and TNF-alpha. These results suggest that DR improves immune function through the changes in indicators related to fatigue and the regulatory effects on immunological parameters, such as NO and TNF-alpha productions. 相似文献
142.
An E Jeong CB Cha C Kim do H Lee H Kong H Kim J Kim JW 《Langmuir : the ACS journal of surfaces and colloids》2012,28(9):4095-4101
Corneocytes represents the main water reservoir of stratum corneum, and that ability intimately arises from their architecture and total composition. Here we describe a novel method for fabricating a microgel-in-liposome (M-i-L) structure consisting of a sodium hyaluronate microgel and a lipid membrane envelop in order to mimic corneocyte cell structures. The essence of our approach is to use a lecithin-based microemulsion with a very low interfacial tension between the water droplet and oil continuous phase. Using this emulsion enables us to stabilize a dispersion of microgel particles without phase separation or aggregation. The addition of excess water produced single-core or multicore microgel particles enveloped in a lipid layer. To demonstrate the applicability of this unique vesicle system, we encapsulated a high concentration of natural moisturizing factor (NMF) in the microgel core and investigated how the M-i-L structure affected the water retention in comparison with other control systems. We have observed that our M-i-L particles with the NMF in the core, which mimicked the corneocyte cell structure, showed an excellent ability to retain water in the system. This experimental result inspired us to investigate how corneocyte cells, which feature a lipid-enveloped hydrogel structure, provide such long-lasting hydration to the skin. 相似文献
143.
Kim KJ Park MS Kim JH Hwang U Lee NJ Jeong G Kim YJ 《Chemical communications (Cambridge, England)》2012,48(44):5455-5457
A new approach for enhancing the electrochemical performance of carbon felt electrodes by employing non-precious metal oxides is designed. The outstanding electro-catalytic activity and mechanical stability of Mn(3)O(4) are advantageous in facilitating the redox reaction of vanadium ions, leading to efficient operation of a vanadium redox flow battery. 相似文献
144.
Shen ZL Goh KK Wong CH Loo WY Yang YS Lu J Loh TP 《Chemical communications (Cambridge, England)》2012,48(47):5856-5858
The synthesis of recyclable ionic liquid-supported imidazolidinone catalyst I and its application in 1,3-dipolar cycloaddition of nitrone with α,β-unsaturated aldehyde with high performance were described. Most importantly, the catalyst I can be recovered and recycled for up to five runs without observing significant decrease in catalytic activity. 相似文献
145.
Synthesis of the rearranged drimane sesquiterpenoids (+)-avarol and (+)-avarone from Wieland-Miescher ketone is described. This synthetic sequence provides convenient access to the natural enantiomers and, based on comparison of the optical rotation of synthetic avarol dimethyl ether with literature data, affords material of significantly higher optical rotation than a natural source. Similar synthetic strategies have been used to obtain several related compounds, including a decalin bearing an exocyclic olefin and a highly substituted cyclohexane, that can be viewed as hybrids of the trans-fused avarol and cis-fused arenarol skeletons. 相似文献
146.
The total synthesis of a new platelet aggregation-inhibiting gamma-lactam PI-091 (1) gave a 1:1 diastereomeric mixture at the gamma-ketal carbon. The high-yielding aldol reaction of an appropriately protected 1,3,4-trihydroxy-4-methyldecan-2-one 42, prepared from D-glucose, with the kinetically generated enolate of 3-methyl-2-butanone provided 43. The resulting diastereomeric mixture of the aldol adduct 43 was converted to a 2,4-alkylated furan 45 via an intramolecular ketalization followed by dehydration. The addition of a singlet oxygen to the alpha-trimethylsilylated furan 48derived from 45 under photochemical conditions efficiently provided an alpha,gamma-dialkylated gamma-hydroxy gamma-lactone 47. The transformation of methyl ketal 52 prepared from 47 into gamma-hydroxy gamma-lactam 53 was achieved by exposure to liquid ammonia in MeOH. The total synthesis of 1 was achieved from 52 through the Dess-Martin periodinane oxidation of the secondary hydroxy group in the side chain. The present total synthesis revealed that the stereogenic carbon center in the side chain in natural 1 is S. 相似文献
147.
Yu-Dong Shen Hai-Qiang Wu Xian-Zhang Bu Lin-Kun An Pei-Qing Liu Yue-Ming Li 《Tetrahedron》2005,61(38):9097-9101
A novel procedure to construct o-naphthothiophenequinones has been achieved from readily available o-benzothiophenquinones and N-dienes via Diels-Alder reaction-aromatization sequence as key steps. The absolute regioselectivity was established via Diels-Alder reaction of o-benzothiophenquinones with rich electron N-dienes. 相似文献
148.
Yaohang Cheng Yuhang He Jie Zheng Hui Yang Jun Liu Guanghui An Guangming Li 《中国化学快报》2021,32(4):1437-1441
A Ru(II)-catalyzed para-difluoroalkylation of aromatic aldehydes and ketones with a transient directing group has been developed. It utilizes less expensive ruthenium catalysts and allows facile access to challenging difluoroalkylated aldehydes. The mechanism studies suggest that the distinct coordination mode of ruthenium complex with imine moieties is responsible for para-selectivity. 相似文献
149.
Li Shuaiqi Han Xiaoxu An Hualiang Zhao Xinqiang Wang Yanji 《Kinetics and Catalysis》2021,62(5):632-640
Kinetics and Catalysis - Ethanol Guerbet condensation (EGC) is a green process for preparing n-butanol and the development of highly effective solid catalysts is still the bottleneck of this... 相似文献
150.
By using a micro-bomb calorimeter, the standard enthalpies of combustion of C60 and C70 have been determined to be - (25 947.1±8.5) and - (29 956.1 ± 8.9) kJ/mol respectively. A g. 1. c. analysis indicated that
the amounts of residual organic solvents in the samples were very small, and their effects on the final results were negligible.
The energy of combustion ofC60 determined in this work is in agreement in the uncertainty interval with that determined by means of traditional calorimeter
using macro amount of sample. The enthalpies of formation of these two substances have been derived. The strain energies in
the molecules of C60 and C70 were estimated by a bond energy scheme and by using corannulene as the model compound, the results estimated from different
methods are very close.
Project supported by the National Natural Science Foundation of China (Grant No. 29473143) 相似文献