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71.
Allium saralicum R.M. Fritsch has been used in Iranian traditional medicine as a remedial supplement for microbial diseases. This paper reports the green synthesis, chemical characterization and antioxidant, cytotoxic, antibacterial and antifungal properties of silver nanoparticles obtained using aqueous extract of A. saralicum leaves. In this synthesis, no surfactants or stabilizers were used. For characterization, UV–visible spectroscopy, transmission electron microscopy, X‐ray diffraction, energy‐dispersive X‐ray spectroscopy and field emission scanning electron microscopy were used. 2,2‐Diphenyl‐1‐picrylhydrazyl was used in experiments to assess the antioxidant potential of the silver nanoparticles, which revealed an impressive prevention in comparison with butylated hydroxytoluene. The synthesized silver nanoparticles at low doses (1–250 μg dl?1) did not show marked cytotoxic activity (against cervical cancer cells (Hela), breast cancer cells (MCF‐7) and human embryonic kidney cells (HEK‐293)). Agar diffusion tests were applied to determine the antibacterial and antifungal characteristics. Compared with all standard antimicrobials, the silver nanoparticles showed higher antibacterial and antifungal activities (p ≤ 0.01). Also, the silver nanoparticles inhibited the growth of all bacteria and fungi at concentrations of 31–250 μg ml?1, and destroyed them at concentrations of 31–500 μg ml?1 (p ≤ 0.01). Because the silver nanoparticles obtained using aqueous extract of A. saralicum leaves have antioxidant, non‐cytotoxic, antifungal and antibacterial potentials, they can be used as a medical supplement or drug.  相似文献   
72.
73.
Recently, metallic nanoparticles have been used for the treatment of several disorders, such as cancer. Indeed, finding the chemotherapeutic drug of nanoparticles is in researching the priority of both developed and developing countries. The present study confirms the ability of aqueous extract of Thymus vulgaris grown under in vitro condition for the biosynthesis of gold nanoparticles (AuNPs). Also, in this study, we indicated the antioxidant, cytotoxicity, and anti-acute myeloid leukemia properties of AuNPs compared to doxorubicin in a leukemic mouse model. The synthesized AuNPs were characterized using different techniques including X-ray diffraction (XRD), energy Dispersive X-ray Spectrometry (EDS), fourier-transform infrared spectroscopy (FT-IR) spectroscopy, ultraviolet–visible spectroscopy (UV–Vis.), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). In vivo design, induction of acute myeloid leukemia was done by 7,12-Dimethylbenz[a]anthracene (DMBA) in 75 mice. Then, the animals were randomly divided into six subgroups, including control, untreated, doxorubicin, AuNPs, T. vulgaris, and HAuCl4. By quantitative real-time PCR, sphingosine-1-phosphate receptor-1 and sphingosine-1-phosphate receptor-5 mRNA expression in lymphocytes were significantly (P ≤ 0.01) raised by treating the leukemic mice with the AuNPs and doxorubicin. Also, AuNPs similar to doxorubicin, significantly (P ≤ 0.01) enhanced the anti-inflammatory cytokines (IL4, IL5, IL10, IL13, and IFNα) and the platelet, lymphocyte, and red blood cell (RBC) parameters and reduced the pro-inflammatory cytokines (IL1, IL6, IL12, IL18, IFNY, and TNFα), and the total white blood cell (WBC), blast, monocyte, neutrophil, eosinophil, and basophil counts as compared to the untreated mice. In vitro design, 2,2-diphenyl-1-picrylhydrazyl (DPPH) test revealed similar antioxidant potentials for doxorubicin and AuNPs. Furthermore, AuNPs similar to doxorubicin had low cell viability dose-dependently against 32D-FLT3-ITD, Human HL-60/vcr, and Murine C1498 cell lines without any cytotoxicity on HUVEC cell line. Above results confirm the excellent antioxidant, cytotoxicity, and anti-acute myeloid leukemia effects of AuNPs compared to doxorubicin. After confirming these results in clinical trial studies, AuNPs can be used as a chemotherapeutic drug for the treatment of acute myeloid leukemia in human.  相似文献   
74.
The aim of the study was the rapid green synthesis of titanium nanoparticles using the aqueous extract of Falcaria vulgaris leaves (TiNPs@FV) and exploring their antioxidant, cytotoxicity, antifungal, antibacterial, and cutaneous wound healing activities under in vitro and in vivo condition. These nanoparticles were characterized by UV-Vis, Fourier transform-infrared(FT-IR), X-ray diffraction XRD), field emission-scanning electron microscopy FE-SEM), and transmission electron microscopy TEM) analyses. The synthesized TiNPs@FV had great cell viability on human umbilical vein endothelial cells and indicted this method was nontoxic. DPPH (2,2-diphenyl-1-picrylhydrazyl) test revealed similar antioxidant potentials for F. vulgaris, TiNPs@FV, and butylated hydroxytoluene. All data of antibacterial, antifungal, and cutaneous wound healing tests were analyzed by SPSS 22 software. In the antimicrobial part of this study, TiNPs@FV indicated higher antifungal and antibacterial effects than all standard antibiotics (p ≤ 0.01). Minimal inhibitory concentration (MIC) and minimal fungicidal concentration of TiNPs@FV against all fungi were at 2–4 mg/mL and 2-8 mg/mL ranges, respectively. But, MIC and minimal bactericidal concentration of TiNPs@FV against all bacteria were at 2-8 mg/mL and 2-16 mg/mL ranges, respectively. In the part of cutaneous wound healing, use of TiNPs@FV ointment significantly (p ≤ 0.01) raised the wound contracture, vessel, hydroxyl proline, hexuronic acid, hexosamine, fibrocyte, and fibrocytes/fibroblast rate and significantly (p ≤ 0.01) decreased the wound area, total cells, neutrophil, and lymphocyte compared to other groups in rats. The results of FT-IR, UV-Vis, XRD, TEM, and FE-SEM confirm that the aqueous extract of F. vulgaris leaves can be used to yield titanium nanoparticles with a notable amount of remedial effects.  相似文献   
75.
Abstract

Medicinal plants play an important role in aquaculture as feed additives. This study aimed to investigate effects of alcoholic extract of acorn on growth performance, body composition, digestive enzymes activity and blood biochemical parameters of rainbow trout (O. mykiss) as a commercially important fish. Five dietary treatments were supplemented: 100, 200, 400 and 600?mg.kg?1 of the extract. Fishes were fed twice per day for 8?weeks, and results showed that acorn extract positively affected all investigated parameters in rainbow trout fishes. Digestive enzymes activity and growth performance were increased, while activity of liver enzymes and cortisol were lowed in comparison to control individuals. Body composition of treated animals was also enhanced. Comparison between treated groups together with integrative biomarker response (IBR) values indicated greatest effects in animals fed with 400 and 600?mg.kg?1 of the extract. Positive effects of the acorn represent promising start point for further studies.  相似文献   
76.
We prove that the exact reconstruction of a function from its samples on any ``sufficiently dense" sampling set can be obtained, as long as is known to belong to a large class of spline-like spaces in . Moreover, the reconstruction can be implemented using fast algorithms. Since a limiting case is the space of bandlimited functions, our result generalizes the classical Shannon-Whittaker sampling theorem on regular sampling and the Paley-Wiener theorem on non-uniform sampling.

  相似文献   

77.
Mixed micellization of dimeric cationic surfactants tetramethylene-1,4-bis(hexadecyldimethylammonium bromide)(16-4-16), hexamethylene-1,6-bis(hexadecyldimethylammonium bromide) (16-6-16) with monomeric cationic surfactants hexadecyltrimethylammonium bromide (CTAB), cetylpyridinium bromide (CPB), cetylpyridinium chloride (CPC), and tetradecyltrimethylammonium bromide (TTAB) have been studied by conductivity and steady-state fluorescence quenching techniques. The behavior of mixed systems, their compositions, and activities of the components have been analyzed in the light of Rubingh's regular solution theory. The results indicate synergism in the binary mixtures. Ideal and experimental critical micelle concentrations (i.e., cmc(*) and cmc) show nonideality, which is confirmed by beta values and activity coefficients. The micelle aggregation numbers (N(agg)), evaluated using steady-state fluorescence quenching at a total concentration of 2 mM for CTAB/16-4-16 or 16-6-16 and 5 mM for TTAB/16-4-16 or 16-6-16 systems, indicate that the contribution of conventional surfactants was always more than that of the geminis. The micropolarity, dielectric constant and binding constants (K(sv)) of mixed systems have also been evaluated from the ratios of respective peak intensities (I(1)/I(3) or I(0)/I(1)).  相似文献   
78.
The present paper reports the investigation of surface morphology, elemental composition, phase changes and field emission properties of Si ion irradiated nickel (Ni) and titanium (Ti). The Ni and Ti targets have been irradiated with 500 keV Si ions generated by Pelletron accelerator at various fluences ranging from 6.9 × 1013 to 77.1 × 1013 ions/cm2. Stopping range of ions in matter analysis revealed higher values of electronic stopping and sputtering yield for Ni as compared with Ti. For both irradiated metals, electronic energy loss dominant over the nuclear stopping. The growth of induced surface structures have been analysed by using field emission scanning electron microscopy (FESEM) analysis. In case of Ni, as the ion fluence increases from 6.9 × 1013 to 65.8 × 1013 ions/cm2, the formation of spherical particulates, agglomers and sputtering is observed. Although in the case of Ti, with the increase of Si ion fluence from 11.6 × 1013 to 77.1 × 1013 ions/cm2, the formation of irregular-shaped particulates along with crater and sputtered channels is observed. X-ray diffraction (XRD) analysis shows that no new phase is identified. However, a significant increase in peak intensity is observed with increasing ion fluence. The variation in crystallite size and dislocation line density is also observed as a function of Si ion fluence. Fourier transform infrared spectroscopy analysis shows that no bands are formed after the Si ion irradiation. Field emission properties of ion-structured Ni and Ti are well correlated with the growth of surface structures observed by SEM and dislocation line density evaluated by XRD analysis.  相似文献   
79.
This critical review provides a systematic classification of the synthetic routes to planar-chiral five-membered metallacycles into several routes, namely C-H bond activation, oxidative addition, transmetallation and optical resolution. As a characteristic of these bulk compounds is that they are synthesized as binary mixtures of enantiomers in proportions varying from the racemate to enantiopure, a review of absolute-configuration determination of the title planar-chiral scalemates is presented. This review is of interest to organic and organometallic synthetic chemists involved in asymmetric synthesis (97 references).  相似文献   
80.
Unlike the common high temperature pyrolysis of carboxymethylcellulose (CMC) targeting activated carbon, this study investigates the pyrolytic behaviour of plain CMC at low temperatures ranging between 260 and 300 °C. Preliminary experiments were conducted using differential scanning calorimetry to define the temperature range necessary for the process. Low-temperature pyrolysis was then simulated using thermogravimetric analysis under inert atmosphere. Investigations reveal that a minimum holding temperature of 260 °C is required for an isothermal process, at which pyrolysis is terminated after around 26 min. Increasing exposure temperature reduces pyrolysis time. Within the range of the investigated sample and CMC particle size, no significant effects could be measured regarding the decomposition behaviour. The resulting char was further analysed using X-ray diffraction and Fourier transform infrared spectroscopy. Visual inspection was conducted using scanning electron microscopy. Upon pyrolysis, originally longitudinally shaped CMC was found to be converted into spherical particles of functionalised amorphous carbon with an average particle size of 41 µm.  相似文献   
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