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81.
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   
82.
Cepharanthine (CEP) has excellent anti-SARS-CoV-2 properties, indicating its favorable potential for COVID-19 treatment. However, its application is challenged by its poor dissolubility and oral bioavailability. The present study aimed to improve the bioavailability of CEP by optimizing its solubility and through a pulmonary delivery method, which improved its bioavailability by five times when compared to that through the oral delivery method (68.07% vs. 13.15%). An ultra-performance liquid chromatography tandem-mass spectrometry (UPLC-MS/MS) method for quantification of CEP in rat plasma was developed and validated to support the bioavailability and pharmacokinetic studies. In addition, pulmonary fibrosis was recognized as a sequela of COVID-19 infection, warranting further evaluation of the therapeutic potential of CEP on a rat lung fibrosis model. The antifibrotic effect was assessed by analysis of lung index and histopathological examination, detection of transforming growth factor (TGF)-β1, interleukin-6 (IL-6), α-smooth muscle actin (α-SMA), and hydroxyproline level in serum or lung tissues. Our data demonstrated that CEP could significantly alleviate bleomycin (BLM)-induced collagen accumulation and inflammation, thereby exerting protective effects against pulmonary fibrosis. Our results provide evidence supporting the hypothesis that pulmonary delivery CEP may be a promising therapy for pulmonary fibrosis associated with COVID-19 infection.  相似文献   
83.
Lead-halide perovskite photovoltaics(PVs)have achieved impressive progress in power conversion efficiencies(PCEs)over the past ten years,accelerating their step forward to next-generation commercial PV technologies[1].As a leading candidate for perovskite PVs,monolithic all-perovskite tandem solar cells(PTSCs)have achieved the best24.8%for small-area devices(0.049 cm^2)in 2019。  相似文献   
84.
磷酸盐钕玻璃、熔石英和BK7是3类用于激光惯性约束聚变(ICF)装置主要光学元件材料.实验中采用不同平均粒径的氧化铈抛光粉对上述3类材料分别进行抛光,对特定材料抛光去除量和抛光粉平均粒径的关系进行了研究.实验表明:由于材料的物理和化学特性不同,特定的材料需选用相应平均粒径大小的抛光粉才能达到最佳的抛光效率.实验还就上述3类高功率激光玻璃材料抛光中各个阶段的抛光粗糙度与抛光粉平均粒径的关系进行了研究,结果表明:某一规格抛光粉的粒径对不同特性材料抛光后的表面粗糙度影响表征情况不同.  相似文献   
85.
In this paper, the DVRT (vector radiative transfer theory of densely distributed random discrete scatters) model to calculate the brightness temperature emitted by radiometer calibration load is presented. It takes the multiple scattering of isolation layer into account, which is neglected by the incoherent homogeneous model often used in calibration. Hence, it works much better than incoherent homogeneous model at millimeter wave band. Furthermore, the iteration of DVRT model is presented, and it proves that the incoherent homogeneous model is just the zero-order solution of DVRT model. Some numerical results are provided in the end.  相似文献   
86.
徐竹 《高分子学报》2021,53(11):30-38
构成主义观点致力于在自然主义的心灵图景中解释自我知识的特殊性与第一人称权威。为此,它主张高阶信念和一阶态度不是相互独立的,而是有着构成性的关系。概念论解释试图从认识主体的概念能力,特别是批判性推理的能力来作出论证。默认权威观点则诉诸日常话语实践的“语法”要求,主张认识主体对自我的态度拥有先天合理的、又可由证据挫败的确信。通过引入“以言行事”的思路,构成主义有希望确立起合理、审慎、有节制的第一人称权威观点。  相似文献   
87.
Main observation and conclusion Chiral-at-metal strategy was developed to resolve the essential sulfoxide pharmaceutical intermediates R-modafinil acid and its ...  相似文献   
88.
Main observation and conclusion Surface-enhanced Raman spectroscopy(SERS)-based bioanalytical technique involves the interaction of SERS-active substrate with c...  相似文献   
89.
A novel spectrofluorimetric method to determine abiraterone acetate and its active metabolite, abiraterone was developed, based on the fact that fluorescence intensity of abiraterone acetate and abiraterone could be enhanced in β-cyclodextrin (β-CD) due to the formation of the inclusion complex. The inclusion interaction of β-CD and abiraterone acetate and the β-cyclodextrin sensitized spectrofluorimetry was examined. The various factors influencing fluorescence were discussed in details. The results showed that under the optimized conditions, the linear range of calibration curve for the determination of biraterone acetate and abiraterone was 0.20?~?6.0 μg/mL, and the detection limit (LOD) was 6.8 (r?=?0.997) or 6.6 ng/mL (r?=?0.996), respectively. No interference was observed from common co-existing substances or pharmaceutical excipient. The method was successfully applied to the analysis of abiraterone acetate in pharmaceutical formulation and abiraterone in human serum/urine.  相似文献   
90.
S. X. Li §  M. Y. Li  R. Zhu  Y. S. Chao 《哲学杂志》2013,93(31):3323-3334
In single-slip-oriented copper single crystals, which were cyclically deformed under constant plastic shear strain amplitude control, a persistent slip band (PSB) was initiated on the persistent slip line (PSL) that first formed in the matrix vein dislocation structure. During intermediate temperature recovery (ITR) treatment in vacuum at 245 to 400°C, the variations in dislocation configurations and other defects of fatigued specimens were studied by using the scanning electron microscopy (SEM) electron channelling contrast (ECC) and the positron annihilation life (PAL) techniques. The results show that the ladders in the PSBs became curved and broken, or escaped locally until the PSBs disappeared completely during ITR treatment. The annihilation of the PSBs and other dislocation structures in the fatigued specimens prolonged the fatigue life to a certain extent.  相似文献   
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