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81.
82.
Lirong Guo Qing Gao Jieqiong Zhu Xiaobao Jin Hui Yin Tao Liu 《Molecules (Basel, Switzerland)》2022,27(9)
Commonly used clinical chemotherapy drugs, such as cyclophosphamide (CTX), may cause injury to the ovaries. Hormone therapies can reduce the ovarian injury risk; however, they do not achieve the desired effect and have obvious side effects. Therefore, it is necessary to find a potential therapeutic candidate for ovarian injury after chemotherapy. N-Benzyl docosahexaenamide (NB-DHA) is a docosahexaenoic acid derivative. It was recently identified as the specific macamide with a high degree of unsaturation in maca (Lepidium meyenii). In this study, the purified NB-DHA was administered intragastrically to the mice with CTX-induced ovarian injury at three dose levels. Blood and tissue samples were collected to assess the regulation of NB-DHA on ovarian function. The results indicated that NB-DHA was effective in improving the disorder of estrous cycle, and the CTX+NB-H group can be recovered to normal levels. NB-DHA also significantly increased the number of primordial follicles, especially in the CTX+NB-M and CTX+NB-H groups. Follicle-stimulating hormone and luteinizing hormone levels in all treatment groups and estradiol levels in the CTX+NB-H group returned to normal. mRNA expression of ovarian development-related genes was positive regulated. The proportion of granulosa cell apoptosis decreased significantly, especially in the CTX+NB-H group. The expression of anti-Müllerian hormone and follicle-stimulating hormone receptor significantly increased in ovarian tissues after NB-DHA treatment. NB-DHA may be a promising agent for treating ovarian injury. 相似文献
83.
Xin Liang Li Li Yan Dong Wei Dong Hongxia Cui Chunhui Xia Tao Xu Chaozhong Wang Jie Zhang Tingting Liu Huimin Sui Chao Gao 《Molecules (Basel, Switzerland)》2022,27(9)
Estrogens added illegally to dietary supplements are hazardous to human health. Traditional detection and analysis methods have many limitations, and we have developed an assay that combines thin-layer chromatography with Raman imaging microscopy (TLC-RIM). The five estrogens (estrone, estradiol, estriol, ethinyl estradiol, and diethylstilbestrol) were initially separated by TLC, then detected by area scanning Raman imaging with a 532 nm laser under a microscope. Raman spectra were obtained for each estrogen, which were used for detecting estrogen illegally added to botanical dietary supplements. The LOD of each estrogen was 0.4, 1.0, 0.8, 0.2, and 0.2 mg/mL, respectively. The matrix in the real sample did not interfere with the detection of estrogens. The method was fast, sensitive, stable, specific, and reliable. 相似文献
84.
85.
Xudong Li Renpeng Yan Xin Yu Deying Chen Jing Gao 《Journal of Russian Laser Research》2013,34(6):586-592
We improve the performance of an acousto-optical Q-switched Nd:YAG 946 nm laser using a convex–plane cavity. We obtain the highest output average power of 2.3 W with a pulse width of 15.3 ns in a 10 kHz 946 nm laser with a convex–plane cavity. The maximum peak power 15.0 kW is about three times higher than that in a plane–plane cavity. Also we investigate the output performances of the pulsed 946 nm laser with the convex–plane cavity at 20 and 50 kHz. 相似文献
86.
数字全息图在微电路检测、粒度分析、透明场测量等小孔径、小视场对象测量和细胞观测等显微测量方面有着广泛的应用前景。根据离轴数字全息图的频谱特点,提出采用复数滤波器,利用计算机及相关算法对离轴数字全息图进行滤波,消除其零级及共轭像,同时可以得到全息图的相位分布。讨论了复数滤波器的设计方法,给出了实验结果。为数字全息图的压缩、再现和相息图制作提供了方便。 相似文献
87.
Hui Ma Lulu Xiao Dongchen Xu Yingrui Geng Xuesong Liu Yong Chen Yongjiang Wu 《Molecules (Basel, Switzerland)》2022,27(9)
Quality control methods of current traditional Chinese medicine (TCM) preparation is time-consuming and difficult to assess in terms of overall efficiency of the drug. A non-destructive rapid near-infrared spectroscopy detection system for key chemical components and biological activity of Lanqin oral solution (LOS), one of the best-selling TCM formulations, was established for comprehensive quality evaluation. Near infrared spectral scanning was carried out on 101 batches of commercial LOS under the penetrated vial state and traditional state. RAW 264.7 cells were cultured to detect the anti-inflammatory ability of LOS, and the reference concentrations of epigoitrin, geniposide, and baicalin were obtained by HPLC. The quantitative models were optimized by three kinds of variable selection methods. The correlation coefficients of prediction value of the models were greater than 0.94. The system also passed the external validation. The performance of the non-invasive models was similar to the traditional models. The established non-destructive system can be applied to the rapid quality inspection of LOS to avoid unqualified drugs from entering the market and ensure drug effectiveness. The biological activity index of LOS was introduced and predicted by NIRs for the first time, which provides a new idea about the quality control of TCM formulations. 相似文献
88.
Yong‐Bok Lee 《Biomedical chromatography : BMC》2013,27(11):1438-1443
A rapid, sensitive and stable high‐performance liquid chromatography (HPLC) method was developed and validated for the simultaneous determination of morniflumate and its major active metabolite, niflumic acid, in human plasma. HPLC analysis was carried out using a 5 µm particle size, C18‐bonded silica column with a mixture of acetonitrile and 0.005 m potassium phosphate monobasic in water (60:40, v/v) as the mobile phase and UV detection at 287 nm. The method involved the treatment with 50 μL of 0.4 m hydrochloric acid for the stability of morniflumate, extraction with diethylether and evaporation to dryness under a nitrogen stream. The lower limit of quantitation for morniflumate and niflumic acid was 50 and 500 ng/mL, respectively. The calibration curves for morniflumate and niflumic acid were linear over the concentration range of 50–20,000 ng/mL and 500–50,000 ng/mL, respectively, with correlation coefficients greater than 0.9995 and inter‐ or intra‐batch coefficients of variation not exceeding 13.79%. The variability (percentage difference) of incurred sample re‐analysis did not exceed 11.72% and all of the repeat samples fell within 20% of the mean value. This assay procedure was applied successfully to an examination of the pharmacokinetics of morniflumate and its metabolite, niflumic acid, in human subjects. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
89.
Nickel hydroxide mesoporous structures are synthesized by a simple method in the presence of different additives (oxalic acid, aminoacetic acid, and sulfosalicylic acid). Structural characterizations reveal that the additives can affect the crystal structure, increase the specific surface area, and reduce the pore size of the products. The electrochemical properties of the synthesized Ni(OH)2 samples are dependent on their crystal phase, surface area, and pore size distribution. Mesoporous β-Ni(OH)2 with poor crystallinity shows high specific capacitances at different current densities and excellent cycling ability. A highest specific capacitance of 1,693 F?g?1 can be achieved at a scan rate of 5 mV?s?1. The results suggest its potential application in electrochemical supercapacitors. 相似文献
90.
Tanmoy Dutta Yong Li Aaron L. Thornton Da‐Ming Zhu Zhonghua Peng 《Journal of polymer science. Part A, Polymer chemistry》2013,51(18):3818-3828
Donor‐acceptor conjugated polymers containing a new imide‐functionalized naphthodithiophene (INDT) as the acceptor unit and a 2,2'‐bithiophene with varied substituents as the donor unit have been synthesized. The bandgaps of these polymers depend strongly on the dihedral angle of the 2,2'‐bithiophene unit. The 3,3'‐dialkoxy substitution (polymers PDOR / PBOR ) leads to near planar bithiophene conformation due to the well‐known S–O short contact, while the 3,3'‐dialkyl substitution (polymer PDR ) results in significant twisting due to the steric effect. Consequently PDOR / PBOR shows the lowest bandgap of 1.82/1.85 eV while PDR has a bandgap of 2.38 eV. Bulk‐heterojunction solar cells of the polymer/fullerene blends have been fabricated. Preliminary results show that PBOR gives the best device performance with power conversion efficiencies as high as 2.45% in air without any thermal annealing treatment, indicating the promising potential of INDT‐containing conjugated polymers for efficient solar cells. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3818–3828 相似文献