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91.
Simultaneous determination of nine lignans from Schisandra chinensis extract using ultra‐performance liquid chromatography with tandem mass spectrometry in rat plasma,urine, and gastrointestinal tract samples: Application to the pharmacokinetic study of Schisandra chinensis 下载免费PDF全文
You‐Jin Kim Hee Ju Lee Chul Young Kim Sun‐Young Han Young‐Won Chin Young Hee Choi 《Journal of separation science》2014,37(20):2851-2863
The fruit of Schisandra chinensis is a well‐known herbal medicine and dietary supplement due to a variety of biological activities including antihepatotoxic and antihyperlipidemic activities. However, the simultaneous validation methodology and pharmacokinetic investigation of nine lignans of S. chinensis extract in biological samples have not been proved yet. Thus, the present study was undertaken to develop the proper sample preparation method and simultaneous analytical method of schisandrol A, gomisin J, schisandrol B, tigloylgomisin H, angeloylgomisin H, schisandrin A, schisandrin B, gomisin N, and schisandrin C in the hexane‐soluble extract of S. chinensis to apply for the pharmacokinetic study in rats. All intra‐ and interprecisions of nine lignans were below 13.7% and accuracies were 85.1–115% and it is enough to evaluate the pharmacokinetic parameters after both intravenous and oral administration of hexane‐soluble extract of S. chinensis to rats. 相似文献
92.
Haodi Wang Li Zhang Binyuan Liu Bing Han Zhongyu Duan Cuiyun Qi Dae‐Won Park Il Kim 《Macromolecular rapid communications》2015,36(18):1646-1650
High molecular weight cyclic poly(ε‐caprolactone)s (cPCLs) with variable ring size are synthesized via light‐induced ring closure of α,ω‐anthracene‐terminated PCL (An‐PCL‐An). The ring size of cPCL is tunable simply by adjusting the polymer concentration from 10 to 100 mg mL−1 in THF. The cycloaddition via the bimolecular cyclization of An‐PC‐An is well characterized by a variety of analyses such as 1H NMR and UV–vis spectroscopies, gel‐permeation chromatography, and differential scanning calorimetry. The reversible dimerization of An induced by heating enables the cyclic PCL to have a switchable “on–off” capability. This novel light‐induced ring‐closure technique can be one of the most powerful candidates for producing various well‐defined cyclic polymers in highly concentrated polymer solution.
93.
Enhanced Static Modulated Fourier Transform Spectrometer for Fast Approximation in Field Application
We discuss the data sampling frequency, the spectral resolution, and the limit for non-aliasing in the static modulated Fourier transform spectrometer based on a modified Sagnac interferometer. The measurement was performed in a very short 4 ms, which is applicable for real time field operation. The improved spectrometer characteristics were used to investigate the spectral properties of an InGaAs light emitting diode. In addition, The measured spectral peak was shifted from 6420 cm−1 to 6365 cm−1, as the temperature increased from 25 °C to 40 °C, when the operating current is fixed to be 0.55 A. As the applied current increased from 0.30 A to 0.55 A at room temperature, the spectral width was broadened from 316 cm−1 to 384 cm−1. Compared to the conventional Fourier transform spectrometer, the measured spectral width by the static modulated Fourier transform spectrometer showed a deviation less than 10%, and the spectral peak shift according to the temperature rise showed a difference within 2%. 相似文献
94.
Young Her Tae-Kyeong Lee Ji Hyeon Ahn Soon Sung Lim Beom-Goo Kang Jung-Seok Park Bora Kim Hyejin Sim Jae-Chul Lee Hyun Sook Kim Tae Heung Sim Hyun Sam Lee Moo-Ho Won 《Molecules (Basel, Switzerland)》2021,26(1)
Since ancient times, various herbs have been used in Asia, including Korea, China, and Japan, for wound healing and antiaging of the skin. In this study, we manufactured and chemically analyzed a novel distillate obtained from a fermented mixture of nine anti-inflammatory herbs (Angelica gigas, Lonicera japonica, Dictamnus dasycarpus Turcz., D. opposita Thunb., Ulmus davidiana var. japonica, Hordeum vulgare var. hexastichon Aschers., Xanthium strumarium L., Cnidium officinale, and Houttuynia cordata Thunb.). The fermentation of natural plants possesses beneficial effects in living systems. These activities are attributed to the chemical conversion of the parent plants to functional constituents which show more potent biological activities. In our current study, the distillate has been manufactured after fermenting the nine oriental medical plants with Lactobacillus fermentum, followed by distilling. We analyzed the chemical ingredients involved in the distillate and evaluated the effects of topical application of the distillate on ultraviolet B (UVB)-induced skin damage in Institute of Cancer Research (ICR) mice. Topical application of the distillate significantly ameliorated the macroscopic and microscopic morphology of the dorsal skin against photodamage induced by UVB radiation. Additionally, our current results showed that topical application of the distillate alleviated collagen disruption and reduced levels of proinflammatory cytokines (tumor necrosis factor alpha and interleukin 1 β expressions) in the dorsal skin against UVB radiation. Taken together, our current findings suggest that the distillate has a potential to be used as a material to develop a photoprotective adjuvant. 相似文献
95.
We introduce the subwavelength transmission of an effective surface plasmon beyond the light zone via the proximity interaction of convection electrons with a metal grating. A comparative analysis of dielectric homogenization and a finite-difference-time-domain simulation shows that out-of-phase-like modes (pi modes) have strong transmission below the cutoff frequency relying on the parametric condition of structural dimension and electronic energy. The synchronous spatial field and charge distribution of the pi mode system confirms the evanescent tunneling effect of the electron-coupled plasmons. 相似文献
96.
In this communication, TiO2 nanocrystalline thin films synthesized by a room temperature (27 degrees C) chemical dip process. To our knowledge, this is first report of the preparation of nanoscale rutile TiO2 particles from common inorganic salt at such low temperature. Interestingly, unprecedented dynamic color change accompanies with titanium dioxide grain size, which can be seen with the naked eye that generated curiosity in our mind to check UV-vis absorption, where significant changes were observed. The room temperature synthesized thin films of rutile titanium dioxide make it a potential candidate for high-compatibility material, which can be used in artificial heart valves. 相似文献
97.
Won Sang Chung 《Fortschritte der Physik》2015,63(6):331-336
In this paper we consider the ‐graded parity generalizing the ordinary (or Z2‐graded ) parity. Using the ‐graded parity operator, we discuss the minimal bosonization of the N=2 SUSY with ‐graded parity. The lowest energy level is shown to be infinitely degenerate. In order to avoid the infinite degeneracy of the ground state we introduce the paraboson algebra to obtain the para‐supersymmetry. Finally, we discuss the hidden SUSY with Z3‐graded parity. 相似文献
98.
This paper addresses a construction of new q‐Hermite polynomials with a full characterization of their main properties and corresponding raising and lowering operator algebra. The three‐term recursive relation as well as the second‐order differential equation obeyed by these new polynomials are explicitly derived. Relevant operator actions, including the eigenvalue problem of the deformed oscillator and the self‐adjointness of the related position and momentum operators, are investigated and analyzed. The associated coherent states are constructed and discussed with an explicit resolution of the induced moment problem. The phase collapse in a q‐deformed boson system is studied. 相似文献
99.
Poly(D,L‐lactide‐co‐glycolide) 50:50 (PLGA)/graphene oxide (GO) nanocomposite films were prepared with various GO weight fractions. A significant enhancement of mechanical properties of the PLGA/GO nanocomposite films was obtained with GO weight fractions. The incorporation of only 5 wt% of GO resulted in an ~2.5‐fold and ~4.7‐fold increase in the tensile strength and Young's modulus of PLGA, respectively. The thermomechanical behaviors of composite films were investigated by dynamic mechanical analysis. Results indicated that the values of Tg and storage moduli of the PLGA/GO composites were higher than those of the pristine PLGA. The improvement in oxygen barrier properties of composites was presumably attributed to the filler effect of the randomly dispersed GO throughout the PLGA matrix. In this work, we also studied in vitro biodegradation behavior. PLGA/GO composite films were hydrolyzed at 37°C for periods up to 49 days. Because of the presence of GO nanosheets, degradation of composite films took place more slowly with increasing GO amounts. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
100.
Young Ki Lee Wonhee Hur Sung Won Lee Sung Woo Hong Sung Woo Kim Jung Eun Choi Seung Kew Yoon 《Experimental & molecular medicine》2014,46(2):e77
14-3-3ζ is related to many cancer survival cellular processes. In a previous study, we showed that silencing 14-3-3ζ decreases the resistance of hepatocellular carcinoma (HCC) to chemotherapy. In this study, we investigated whether silencing 14-3-3ζ affects the radioresistance of cancer stem-like cells (CSCs) in HCC. Knockdown of 14-3-3ζ decreased cell viability and the number of spheres by reducing radioresistance in CSCs after γ-irradiation (IR). Furthermore, the levels of pro-apoptotic proteins were upregulated in CSCs via silencing 14-3-3ζ after IR. These results suggest that 14-3-3ζ knockdown enhances radio-induced apoptosis by reducing radioresistance in liver CSCs. 相似文献