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61.
Martyna Zagrska-Dziok Tomasz Bujak Aleksandra Ziemlewska Zofia Nizio-ukaszewska 《Molecules (Basel, Switzerland)》2021,26(4)
The skin is an organ that is constantly exposed to many external factors that can affect its structure and function. Due to the presence of different cannabinoid receptors on many types of skin cells, cannabinoids can interact directly with them. Therefore, as part of this work, the impact of two types of Cannabis sativa L. herb extracts on keratinocytes and fibroblasts was assessed. The content of biologically active compounds such as phenols, flavonoids, chlorophylls and cannabinoids was evaluated. The antioxidant capacity of prepared extracts using the DPPH radical, H2DCFDA probe and measurement of superoxide dismutase activity was also assessed. The cytotoxicity of hemp extracts was determined using the Alamar Blue, Neutral Red and LDH assays. The ability of the extracts to inhibit the activity of matrix metalloproteinases, collagenase and elastase, was assessed. Preparations of model hydrogels were also prepared and their effect on transepidermal water loss and skin hydration was measured. The obtained results indicate that hemp extracts can be a valuable source of biologically active substances that reduce oxidative stress, inhibit skin aging processes and positively affect the viability of skin cells. The analysis also showed that hydrogels based on cannabis extracts have a positive effect on skin hydration. 相似文献
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Iwona Łakomska Anna Kaźnica Romana Joachimiak Andrzej Marszałek Jerzy Sitkowski Lech Kozerski Tomasz Drewa 《Chemical Papers》2011,65(3):308-314
A novel platinum(IV) coordination compound with 6-mercaptopurine (6-Hmp) has been synthesised and characterised by IR and
NMR spectroscopy. Spectroscopic parameters indicate the presence of two chelate (S-6, N-7) monodeprotonated ligands and two
chloride ions in the coordination sphere of [PtCl2(6-mp)2] · H2O (I). Two Pt(IV) coordination compounds, [PtCl2(6-mp)2] · H2O (I) and [PtCl4(dbtp)2] (II), were used in the in vivo test against B16 mouse melanoma tumours. Cytotoxic activity of compound II against the tumour cells was found to be high (LC10 = 2.6 μM, LC50 = 17.0 μM, LC90 = 58.0 μM) compared to that of cisplatin. 相似文献
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67.
One investigates a generalization of difference calculus and applies it to solve the functional equations of second order.
Presented at the 11th Colloquium “Quantum Groups and Integrable Systems”, Prague, 20–22 June 2002.
This work is supported in part by KBN grant 2 PO3 A 012 19. 相似文献
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Wesołowski TA 《Physical review letters》2002,88(20):209701; author reply 209702
70.
Kaczmarek T 《The Journal of the Acoustical Society of America》2005,117(5):3149-3156
In this study we investigate the perception of the velocity of linearly moving sound sources passing in front of a listener. The binaural simulation of motion used in two psychoacoustical experiments includes changes in the overall sound pressure level, the Doppler effect, and changes in interaural time differences. These changes are considered as cues for the perception of velocity. The present experiments are an extension of the experiments performed by Lutfi and Wang [J. Acoust. Soc. Am. 106, 919-928 (1999)]. The results of Experiment I show that the differential velocity threshold is independent of the reference velocity (10, 20, 30, and 40 m/s), varying across listeners from 1.5 to 4.6 m/s. In Experiment II, a method based on the successive elimination of cues in compared pairs of signals was employed to estimate the weights of potential cues for velocity discrimination. The magnitudes of all underlying cues at thresholds are reported. The experimental results show the subject's preference for the Doppler cue and a weakest sensitivity to the cue related with interaural time differences. Finally, it was found that spatial differences in the source location at the endpoints of the motion trajectory are not a significant factor in the velocity discrimination task. 相似文献