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51.
Berberine (BBR), a potential bioactive agent, has remarkable health benefits. A substantial amount of research has been conducted to date to establish the anticancer potential of BBR. The present review consolidates salient information concerning the promising anticancer activity of this compound. The therapeutic efficacy of BBR has been reported in several studies regarding colon, breast, pancreatic, liver, oral, bone, cutaneous, prostate, intestine, and thyroid cancers. BBR prevents cancer cell proliferation by inducing apoptosis and controlling the cell cycle as well as autophagy. BBR also hinders tumor cell invasion and metastasis by down-regulating metastasis-related proteins. Moreover, BBR is also beneficial in the early stages of cancer development by lowering epithelial–mesenchymal transition protein expression. Despite its significance as a potentially promising drug candidate, there are currently no pure berberine preparations approved to treat specific ailments. Hence, this review highlights our current comprehensive knowledge of sources, extraction methods, pharmacokinetic, and pharmacodynamic profiles of berberine, as well as the proposed mechanisms of action associated with its anticancer potential. The information presented here will help provide a baseline for researchers, scientists, and drug developers regarding the use of berberine as a promising candidate in treating different types of cancers.  相似文献   
52.
In this article, we propose a novel image encryption algorithm by using the linear fractional transformation (LFT) substitution boxes and tangent-delay for elliptic reflecting cavity (TD-ERCS) chaotic sequence. In addition, we apply the proposed approach to an image and come to know that the correlation analysis, UACI analysis, and NPCR analysis of proposed algorithm are much improved than many existing techniques and very easy to put into practice.  相似文献   
53.
Molecular Diversity - A new application of α-alkoxymethylphosphonium salts in the nucleophilic phenylation of carbonyl compounds is demonstrated. Phenylation of aldehydes, ketones and acyl...  相似文献   
54.
Medicinal plants and their derived compounds have drawn the attention of researchers due to their considerable impact on human health. Among medicinal plants, mint (Mentha species) exhibits multiple health beneficial properties, such as prevention from cancer development and anti-obesity, antimicrobial, anti-inflammatory, anti-diabetic, and cardioprotective effects, as a result of its antioxidant potential, combined with low toxicity and high efficacy. Mentha species are widely used in savory dishes, food, beverages, and confectionary products. Phytochemicals derived from mint also showed anticancer activity against different types of human cancers such as cervix, lung, breast and many others. Mint essential oils show a great cytotoxicity potential, by modulating MAPK and PI3k/Akt pathways; they also induce apoptosis, suppress invasion and migration potential of cancer cells lines along with cell cycle arrest, upregulation of Bax and p53 genes, modulation of TNF, IL-6, IFN-γ, IL-8, and induction of senescence phenotype. Essential oils from mint have also been found to exert antibacterial activities against Bacillus subtilis, Streptococcus aureus, Pseudomonas aeruginosa, and many others. The current review highlights the antimicrobial role of mint-derived compounds and essential oils with a special emphasis on anticancer activities, clinical data and adverse effects displayed by such versatile plants.  相似文献   
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Gondal MA  Dastageer A  Shwehdi MH 《Talanta》2004,62(1):131-141
A photoacoustic (PA) spectrometer with high selectivity and sensitivity has been developed for trace gas analysis and for the detection of gas leak at part per trillion by volume (pptV) level. This PA system comprises of a resonant photoacoustic cell, a pulsed line tunable CO2 laser as an excitation source and a sensitive electret microphone as a photoacoustic detector with an option to trigger the safety alarm system for early warning of gas leaks. In this work, three resonant PA cells with various geometries have been developed at our laboratory for the detection of photoacoustic signal using pulsed laser system and their comparative performance have been studied. As a special application of this PA system, the detection of sulfur hexa fluoride (SF6) gas using these three cells has been carried out for optimizing the sensitivity. Besides this, our PA system can very well be applied for pollution monitoring and detection of hazardous gases in a noisy environment.  相似文献   
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This paper shows the evolution of density and temperature of multi-charged ions in an electron beam ion trap (EBIT). Three cases are studied: the continuous neutral gas injection, ion source injection, and evaporative cooling. The effects of the neutral gas density, axial potential, and the beam current density on the ions evolution are discussed.  相似文献   
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Gondal MA  Mastromarino J 《Talanta》2000,53(1):147-154
Light detection and ranging (lidar) system has been developed for remote monitoring of the environment. The system has been tested for measuring the size of clouds and by measurement of differential absorption due to pollutant gases like NO(2) and SO(2) in a cell. The lidar measurements revealed strong scattered signals from clouds situated around 11 km above the earth surface. The lidar data indicates that cloud thickness varied from 0.8 to 3.6 km at various times.  相似文献   
60.
A substitution box is used to induce nonlinearity in plaintext for encryption systems. Recently, the application of chaotic maps to encryption applications has resulted in some interesting nonlinear transformations. In this paper, we propose an efficient method to design nonlinear components for block ciphers that are based on TD-ERCS chaotic sequence. The new substitution box is analyzed for nonlinearity, bit independence, strict avalanche criterion, generalized majority logic criterion, and differential and linear approximation probabilities. The results show high resistance to differential and linear cryptanalysis in comparison to some recently proposed chaotic substitution boxes.  相似文献   
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