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41.
Multicompound determination for the quality control of traditional Chinese medicine (TCM) may often be inadequate, since these compounds may not be associated with, or fully represent, the clinical effects of TCM. Moreover, the individual contributions of each constituent to the pharmacological effect are often not considered. In China, Porana sinensis is widely used as a substitute for Erycibe sources to treat joint pain and rheumatoid arthritis. The existing quality control methods for P. sinensis neither consider the individual contributions of various compounds nor control the actual quality associated with different clinical efficacies. In the present study, a novel efficacy-oriented approach, named the effect-constituent index (ECI), was established for P. sinensis. Analyses of the spectrum–effect relationship and components in rat plasma were conducted to systematically and scientifically select quality markers. Quantitative analysis of multicomponents via a single marker method was introduced to enhance the practical application value of the established ECI. The established ECI shows a good ability to distinguish and predict the bioeffect-based quality of P. sinensis. The present study also provides a reference for the establishment and application of ECI as a quality control method for TCMs.  相似文献   
42.
Song  Ying  Liu  Renwei  Li  Shaofan  Kang  Zhuang  Zhang  Feng 《Meccanica》2020,55(4):961-976
Meccanica - In this work, a bond-based peridynamic de-icing model has been developed to simulate the thermo-mechanical ice removal process of frozen structures. In the proposed numerical method,...  相似文献   
43.
Feng  Tian  Guo  Lihong  Wu  Baowei  Chen  YangQuan 《Nonlinear dynamics》2020,102(4):2467-2478
Nonlinear Dynamics - In this paper, a class of switched fractional-order continuous-time systems with order $$0<\alpha <1$$ is investigated. First, an interesting property of...  相似文献   
44.
Jiang  Sen  Ji  Hua  Feng  Donglin  Li  Qian  Wu  Sunke  Chen  Zhi 《Meccanica》2020,55(6):1379-1391
Meccanica - This paper introduces an analytical approach to optimize the textured bearing with cavitation to improve the load support. For this purpose, a grooved parallel slider bearing is...  相似文献   
45.
Metal halide perovskites have demonstrated impressive properties for achieving efficient monochromatic light-emitting diodes. However, the development of white perovskite light-emitting diodes (PeLEDs) remains a big challenge. Here, we demonstrate a single-emissive-layer all-perovskite white PeLED using a mixed halide perovskite film as the emissive layer. The perovskite film consists of separated mixed halide perovskite phases with blue and red emissions, which are beneficial for suppressing halide anion exchange and preventing charge transfer. As a result, the white PeLED shows balanced white light emission with Commission Internationale de L''Eclairage coordinates of (0.33, 0.33). In addition, we find that the achievement of white light emission from mixed halide perovskites strongly depends on effective modulation of the halide salt precursors, especially lead bromide and benzamidine hydrochloride in our case. Our work provides very useful guidelines for realizing single-emissive-layer all-perovskite white PeLEDs based on mixed halide perovskites, which will spur the development of high-performance white PeLEDs.

We demonstrated a single-emissive-layer all-perovskite white light-emitting diode based on a mixed halide perovskite film.  相似文献   
46.
A facile and environmentally friendly approach has been developed to prepare yolk‐shell porous microspheres of calcium phosphate by using calcium L ‐lactate pentahydrate (CL) as the calcium source and adenosine 5′‐triphosphate disodium salt (ATP) as the phosphate source through the microwave‐assisted hydrothermal method. The effects of the concentration of CL, the microwave hydrothermal temperature, and the time on the morphology and crystal phase of the product are investigated. The possible formation mechanism of yolk‐shell porous microspheres of calcium phosphate is proposed. Hemoglobin from bovine red cells (Hb) and ibuprofen (IBU) are used to explore the application potential of yolk‐shell porous microspheres of calcium phosphate in protein/drug loading and delivery. The experimental results indicate that the as‐prepared yolk‐shell porous microspheres of calcium phosphate have relatively high protein/drug loading capacity, sustained protein/drug release, favorable pH‐responsive release behavior, and a high biocompatibility in the cytotoxicity test. Therefore, the yolk‐shell porous microspheres of calcium phosphate have promising applications in various biomedical fields such as protein/drug delivery.  相似文献   
47.
易志红  白洋  陈立荪  徐峰  陈利江 《应用数学》2015,37(11):951-954
目的 观察丹酚酸A 对H2O2所致大鼠脑微血管内皮细胞(RCMECs)氧化损伤的保护作用,并探讨其可能的作用机 制。方法 分离并培养大鼠脑微血管内皮细胞,用H2 O2 损伤的方法建立氧自由基损伤模型。采用丹酚酸A 进行干预后,分别测定细胞培养液中乳酸脱氢酶(LDH)活性、血栓素B2(TXB2)水平、6- 酮基前列腺素1α(6-keto-PGF1α)的含量,以及细胞内和培养液中脂质过氧化产物丙二醛(MDA)含量和超氧化物歧化酶(SOD)的活性。结果 H2O2致RCMECs 氧化损伤后,细胞LDH 释放水平、TXB2和MDA 的含量均明显增加,同时6-keto-PGF1α 含量和SOD 活性显著下降;而丹酚酸A 预处理后能呈浓度依赖性的降低RCMECs 氧化损伤后LDH 水平、TXB2含量和细胞内外的MDA 含量,提高受损细胞6-keto-PGF1α 的表达和细胞内外SOD 活性。结论 丹酚酸A 对H2O2所致RCMECs 氧化损伤具有保护作用,其机制可能与其抗氧化作用有关。  相似文献   
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50.
The salt effects on molecular orientation at air/liquid methanol interface were investigated by the polarization-dependent sum frequency generation vibrational spectroscopy(SFG-VS). We clarified that the average tilting angle of the methyl group to be u = 308 58 at the air/pure methanol surface assuming a d-function orientational distribution. Upon the addition of 3 mol/L Na I, the methyl group tilts further away from the surface normal with a new u = 418 38. This orientational change does not explain the enhancement of the SFG-VS intensities when adding Na I, implying the number density of the methanol molecules with a net polar ordering in the surface region also changed with the Na I concentrations. These spectroscopic findings shed new light on the salt effects on the surfaces structures of the polar organic solutions. It was also shown that the accurate determination of the bulk refractive indices and Raman depolarization ratios for different salt concentrations is crucial to quantitatively interpret the SFG-VS data.  相似文献   
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