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71.
Objectives Green tea (Camellia sinensis) is a kind of unfermented tea that retains the natural substance in fresh leaves to a great extent. It is regarded as the second most popular drink in the world besides water. In this paper, the phytochemistry, pharmacology, and toxicology of green tea are reviewed systematically and comprehensively. Key findings Green tea has been demonstrated to be good for human health. Nowadays, multiple pharmacologically active components have been isolated and identified from green tea, including tea polyphenols, alkaloids, amino acids, polysaccharides, and volatile components. Recent studies have demonstrated that green tea shows versatile pharmacological activities, such as antioxidant, anticancer, hypoglycemic, antibacterial, antiviral, and neuroprotective. Studies on the toxic effects of green tea extract and its main ingredients have also raised concerns including hepatotoxicity and DNA damage. Summary Green tea can be used to assist the treatment of diabetes, Alzheimer’s disease, oral cancer, and dermatitis. Consequently, green tea has shown promising practical prospects in health care and disease prevention.  相似文献   
72.
To explore the drying characteristics of soybean dregs and a nondestructive moisture content test method, in this study, soybean dregs were dried with hot air (80 °C), the moisture content was measured using the drying method, water status was analyzed using low-field nuclear magnetic resonance (LF-NMR) and the moisture content prediction models were built and validated. The results revealed that the moisture contents of the soybean dregs were 0.57 and 0.01 g/g(w.b.), respectively, after drying for 5 and 7 h. The effective moisture diffusivity increased with the decrease in moisture content; it ranged from 5.27 × 10−9 to 6.96 × 10−8 m2·s−1. Soybean dregs contained bound water (T21), immobilized water (T22) and free water (T23 and T23’). With the proceeding of drying, all of the relaxation peaks shifted left until a new peak (T23’) appeared; then, the structure of soybean dregs changed, and the relaxation peaks reformed, and the peak shifted left again. The peak area may predict the moisture content of soybean dregs, and the gray values of images predict the moisture contents mainly composed of free water or immobilized water. The results may provide a reference for drying of soybean dregs and a new moisture detection method.  相似文献   
73.
Myocardial infarction (MI) is the leading cause of premature death among adults. Cardiomyocyte death and dysfunction of the remaining viable cardiomyocytes are the main pathological factors of heart failure after MI. Mitochondrial complexes are emerging as critical mediators for the regulation of cardiomyocyte function. However, the precise roles of mitochondrial complex subunits in heart failure after MI remain unclear. Here, we show that NADH:ubiquinone oxidoreductase core subunit S1 (Ndufs1) expression is decreased in the hearts of heart failure patients and mice with myocardial infarction. Furthermore, we found that cardiac-specific Ndufs1 overexpression alleviates cardiac dysfunction and myocardial fibrosis in the healing phase of MI. Our results demonstrated that Ndufs1 overexpression alleviates MI/hypoxia-induced ROS production and ROS-related apoptosis. Moreover, upregulation of Ndufs1 expression improved the reduced activity of complex I and impaired mitochondrial respiratory function caused by MI/hypoxia. Given that mitochondrial function and cardiomyocyte apoptosis are closely related to heart failure after MI, the results of this study suggest that targeting Ndufs1 may be a potential therapeutic strategy to improve cardiac function in patients with heart failure.Subject terms: Heart failure, Myocardial infarction, Myocardial infarction  相似文献   
74.
Pyroptosis is a programmed cell death widely studied in cancer cells for tumour inhibition, but rarely in dendritic cell (DC) activation for vaccine development. Here, we report the synthesis of sodium stabilized mesoporous aluminosilicate nanoparticles as DC pyroptosis modulators and antigen carriers. By surface modification of sodium-stabilized four-coordinate aluminium species on dendritic mesoporous silica nanoparticles, the resultant Na-IVAl-DMSN significantly activated DC through caspase-1 dependent pyroptosis via pH responsive intracellular ion exchange. The released proinflammatory cellular contents further mediated DC hyperactivation with prolonged cytokine release. In vivo studies showed that Na-IVAl-DMSN induced enhanced cellular immunity mediated by natural killer (NK) cells, cytotoxic T cells, and memory T cells as well as humoral immune response. Our results provide a new principle for the design of next-generation nanoadjuvants for vaccine applications.

Na-IVAl-DMSN acts as both antigen carriers and modulators to “hyperactivate” dendritic cells (DCs) via potassium (K+) efflux dependent pyroptosis, eventually leading to enhanced adaptive and innate immunity.  相似文献   
75.
Dimethyl carbonate is an important green chemical that has been widely used in the chemical industry. In the production of dimethyl carbonate, methanol oxidative carbonylation has been studied, but the conversion ratio of dimethyl carbonate using this method is too low, and the subsequent separation requires a large amount of energy due to methanol and dimethyl carbonate being azeotrope. In this paper, the strategy of “reaction instead of separation” is proposed. Based on this strategy, a novel process is developed to combine the production of DMC with that of dimethoxymethane (DMM) and dimethyl ether (DME). The co-production process was simulated using Aspen Plus software, and the product purity was up to 99.9%. The exergy analysis of the co-production process and the existing process was carried out. The exergy destruction and exergy efficiency were compared with those of the existing production processes. The results show that the exergy destruction of the co-production process is about 276% less than that of the single-production processes, and the exergy efficiencies in the developed co-production process are significantly improved. The utility loads of the co-production process are significantly lower than that of the single-production process. The developed co-production process increases the methanol conversion ratio to 95%, with a reduced energy requirement. It is proved that the developed co-production process can provide an advantageous option over the existing processes with improved energy efficiency and material savings. The strategy of “reaction instead of separation” is feasible. A new strategy is proposed for azeotrope separation.  相似文献   
76.
A straightforward immunoassay based on surface enhanced fluorescence (SEF) has been demonstrated using a fluorescent immune substrate and antibody functionalized-silver nanoparticles. Unlike the conventional SEF-based immunoassay, which usually uses the dye-labeled antibodies and the metallic nanostructured-substrates, the presented immune system does not need the antibodies to be labeled with dye molecules. Thus, this immunoassay can be easily applied to the detection of a wide range of target antigens, which is of great importance for its practical application. The experimental results show that this immunoassay has a good specificity as well as the capacity of quantitative detection. Basically, the surface density of the immuno-adsorbed silver nanoparticles increases with the increased amount of target antigens, resulting in a fluorescence enhancement up to around 7 fold. The dose-responsive performance of the immunoassay has been investigated and the limit of detection (LOD) is 1 ng/mL. Due to its simple preparation method and the wide range of detectable antigens, this presented immunoassay is expected to be helpful for extending the SEF-based application.  相似文献   
77.
The directional scattering in photorefractive SBN crystal is reported.The self-pumped phase conjugation has been realized with the feedback of this directional scattering andthe performance parameters are compared with those of cat self-pumped phase conjugator.  相似文献   
78.
79.
Let C be a regular semigroup with an inverse transversal C° and let C be generated by its idempotents. Following W. D. Munn and T. E. Hall’s idea, in this paper, a fundamental regular semigroup T C,C° with an inverse transversal T C,C° ° is constructed such that the following holds. For any regular semigroup S with an inverse transversal S° and 〈E(S)〉 = C, C° = CS°, there is a homomorphism φ from S to T C,C° such that the kernel of φ is the maximum idempotent-separating congruence on S, and φ satisfies: (1) φ| C is a homomorphism from C onto 〈E(T C,C°)〉 ; (2) φ| S° is a homomorphism from S° to T C,C° °. In particular, S is fundamental if and only if S is isomorphic to a full subsemigroup of T C,C°. Our fundamental regular semigroup T C,C° is isomorphic to a subsemigroup of the Hall semigroup of C but it is easier to handle. Its elements are partial transformations, and the operation—although not the usual composition—is defined by means of composition.  相似文献   
80.
In this paper,attention is focused on the intensity moments of the Hermite-Cosh-Gaussian (HChG) laser beams from the zero-order to the fourth-order.The frequently used parameters such as the power in bucket (PIB),the beam width,the curvature radius,the far field divergence,the M2-factor,the Rayleigh length and the kurtosis are calculated in terms of the intensity moments.Figures show the influence of the mode index and the decentered parameter,which are the critical parameters of the HChG beams.Moreover,the center of the gravity of the radiation field and the symmetry are discussed along with the propagation axis.Finally,the power fraction within the beam width defined by the second moments is illustrated with numerical method.  相似文献   
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