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71.
The Mediterranean diet is a central element of a healthy lifestyle, where polyphenols play a key role due to their anti-oxidant properties, and for some of them, as nutripharmacological compounds capable of preventing a number of diseases, including cancer. Due to the high prevalence of intestinal cancer (ranking second in causing morbidity and mortality), this review is focused on the beneficial effects of selected dietary phytophenols, largely present in Mediterranean cooking: apigenin, curcumin, epigallocatechin gallate, quercetin-rutine, and resveratrol. The role of the Mediterranean diet in the prevention of colorectal cancer and future perspectives are discussed in terms of food polyphenol content, the effectiveness, the plasma level, and the importance of other factors, such as the polyphenol metabolites and the influence of the microbiome. Perspectives are discussed in terms of microbiome-dependency of the brain-second brain axis. The emergence of polyphenol formulations may strengthen the efficiency of the Mediterranean diet in the prevention of cancer.  相似文献   
72.
73.
The 5G technology is a promising technology to cope with the increasing demand for higher data rate and quality of service. In this paper, two proposed techniques are implemented for multiple input multiple output (MIMO) self-heterodyne OFDM system to enhance data rate and minimize the bit error rate (BER). In both of the two proposed techniques, Band Selection (BS) approach is used, once with Space Time Block Coded (STBC) for the first proposed technique (BS- STBC), and once again with Frequency Space Time Block Coded (FSTBC) for the second proposed technique (BS-FSTBC). The use of the BS in the proposed techniques helps to choose the sub-band with better subchannels gains for sending the information and consequently, minimize the BER. Moreover, the use of the FSTBC instead of STBC helps to use the spectral efficiently and hence increase data rate. The simulation results show that the proposed techniques BS-STBC and BS-FSTBC, for the MIMO self-heterodyne OFDM system, provide a great enhancement in the BER performance when compared to the conventional techniques. Moreover, the simulation results show that the first proposed technique BS-FSTBC outperform the second propose technique BS-STBC in term of the BER performance.  相似文献   
74.
A multiresidue method was studied for determination of 323 pesticides representing a wide range of physicochemical properties in dry herbs (chamomile and parsley) based on QuEChERS method and LC-ESI-MS/MS analysis. In the current study, three different parameters were optimised for a higher accuracy and a lower matrix effects: extraction procedures, cleanup and matrix effect. Optimum extraction efficiency was obtained at sample hydration of 10 mL water on 2 g dry herbs and soaking time for 10 min. Use of different extraction techniques supported the use of mechanical shaker in comparison with ultrasound and handed shaking. As a way to remove interfering components from final extract, different cleanup techniques were studied: three dispersive solid phase extraction (D-SPE) (C18, primary secondary amine and graphitised carbon black) have been investigated; matrix effect was reduced, but several pesticides were lost during the cleanup process. Unlike the SPE (hydrophilic lipophilic balanced polymer) produced a good recovery with all substances without expected reduction in matrix effect. Moreover, sample dilution and LC-MS/MS injection volume were studied, 3 µL injection volume was found to be the best sensitive condition without sample dilution. The developed method was validated by performing recovery tests at 0.01, 0.05 and 0.1 mg/kg, the average recoveries ranged from 70% to 120%. The reproducibility expressed as relative standard deviation (RSD %) was ≤ 20%.  相似文献   
75.
We report the use of switchable lipids to improve the endosomal escape and cytosolic delivery of cell‐impermeable compounds. The system is based on a conformational reorganization of the lipid structure upon acidification, as demonstrated by NMR spectroscopic studies. When incorporated in a liposome formulation, the switchable lipids triggered bilayer destabilization through fusion even in the presence of poly(ethylene glycol). We observed 88 % release of sulforhodamine B in 15 min at pH 5, and the liposome formulations demonstrated high stability at pH 7.4 for several months. By using sulforhodamine B as a model of a highly polar drug, we demonstrated fast cytosolic delivery mediated by endosomal escape in HeLa cells, and no toxicity.  相似文献   
76.
The title compound was prepared and converted to 2-hydrazinyl-1,2-dihydro-4H-benzo[d][1,3]thiazin-4-one which was utilized to synthesize fused heterocyclic systems, namely benzotriazolothiazinone derivatives, as well as, nonfused heterocyclic systems such as pyrazolyl-benzothiazinones, benzothiazinylpyridazine and imidazolylbenzothiazinone derivatives via reaction with formamide, acetic acid, ethyl cyanoacetate, maleic anhydride and benzaldehyde followed by treatment with glycine, respectively. All compounds have been structurally characterized by means of IR, MS, and 1H-NMR spectra. The synthesized compounds were evaluated in vitro for their antiproliferative activity against HePG-2 and MCF-7 cell lines. 2H-Benzo[d][1,3]thiazine-2,4(1H)-dithione and 2-thioxo-1,2-dihydro-4H-benzo[d][1,3]thiazin-4-one were the most potent against the two cancer cells compared to that of the reference compound doxorubicin. Most of the synthesized compounds also exhibited good cytotoxic activity.  相似文献   
77.
The results of activity concentration measurements of natural occurring radioactive nuclides 238U, 235U, 232Th, 226Ra, and 40K in surface soil samples collected in the area of cities Tuzla and Lukavac, northeast region of Bosnia and Herzegovina were presented. Soil sampling was conducted at the localities that are situated in the vicinity of industrial zones of these cities. The measured activity was in the range from (8?±?4) to (95?±?28) Bq kg–1 for 238U, from (0.41?±?0.06) to (4.6?±?0.7) Bq kg–1 for 235U, from (7?±?1) to (66?±?7) Bq kg–1 for 232Th, from (6?±?1) to (55?±?6) Bq kg–1 for 226Ra, and from (83?±?12) to (546?±?55) Bq kg–1 for 40K. In order to evaluate the radiological hazard of the natural radioactivity for people living near industrial zones, the absorbed dose rate, the annual effective dose and the radium equivalent activity have been calculated and compared with the internationally approved values.  相似文献   
78.
The aim of the present work is to study the effect of gamma radiation on the lipid part of the erythrocyte membrane, and to test the efficiency of lipoic acid as a radioprotector. This effect was evaluated using electron paramagnetic resonance (EPR), and Fourier transform infrared (FT-IR) spectroscopy. The results showed an increase in the number of spin density by 14%, 22% and 65% after exposure to 25, 50 and 100 Gy respectively; whereas there was a decline in the obtained density after incubation with lipoic acid by a factor of approximately 32%. The FT-IR spectra of the irradiated erythrocytes samples showed a marked decrease in the intensity of all characteristic peaks, which increased as the irradiation dose increased. The second-derivative of these spectra, allow the conformationally sensitive membrane acyl chain methylene stretching modes to be separated from the protein (mostly hemoglobin) vibrations that dominate the spectra of intact cells. The 2850 cm−1 band showed changes in the band shape and position after exposure to 50 and 100 Gy. Therefore it can be concluded that the band at 2850 cm−1 only is useful in monitoring the radiation effect of the lipids cell membrane intact cells.  相似文献   
79.
The fungal metabolite TAN‐2483B has a 2,6‐trans‐relationship across the pyran ring of its furo[3,4‐b]pyran‐5‐one core, which has thwarted previous attempts at its synthesis. We have now developed a chiral pool approach to this core and prepared side‐chain analogues of TAN‐2483B. The synthesis relies on ring expansion of a reactive furan ring‐fused dibromocyclopropane and alkynylation of the resulting pyran. The furan ring is constructed by palladium‐catalysed carbonylative lactonisation. Various side‐chains are appended through Wittig‐type chemistry. The prepared analogues showed micromolar activity towards cancer cell lines HL‐60, 1A9 and MCF‐7 and certain human disease‐relevant kinases, including Bruton's tyrosine kinase (Btk).  相似文献   
80.
5‐Amino‐3‐phenyl‐1‐(2,4,6‐trichlorophenyl)‐1H‐thieno[3,2‐c]pyrazole‐6‐carbonitrile ( 2 ) was designed and synthesized by one‐pot multicomponent reaction. Compound 2 was reacted with different reagents to obtain new condensed moieties with our thienopyrazole skeleton. The compounds were prepared by using environmentally benign techniques as microwave irradiation, ultrasonic irradiation, and ball‐milling. The structure of the prepared compounds was elucidated through spectroscopic methods. The new compounds were evaluated for their in vitro antibacterial and antifungal potentialities.  相似文献   
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