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排序方式: 共有451条查询结果,搜索用时 15 毫秒
71.
Shahira M. Ezzat Rana M. Merghany Passent M. Abdel Baki Nariman Ali Abdelrahim Sohaila M. Osman Mohamed A. Salem Sheila I. Peña-Corona Hernán Cortés Lashyn Kiyekbayeva Gerardo Leyva-Gómez Javad Sharifi-Rad Daniela Calina 《Molecular nutrition & food research》2024,68(8):2400063
Phenethyl isothiocyanate (PEITC), a compound derived from cruciferous vegetables, has garnered attention for its anticancer properties. This review synthesizes existing research on PEITC, focusing on its mechanisms of action in combatting cancer. PEITC has been found to be effective against various cancer types, such as breast, prostate, lung, colon, and pancreatic cancers. Its anticancer activities are mediated through several mechanisms, including the induction of apoptosis (programmed cell death), inhibition of cell proliferation, suppression of angiogenesis (formation of new blood vessels that feed tumors), and reduction of metastasis (spread of cancer cells to new areas). PEITC targets crucial cellular signaling pathways involved in cancer progression, notably the Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB), Protein Kinase B (Akt), and Mitogen-Activated Protein Kinase (MAPK) pathways. These findings suggest PEITC's potential as a therapeutic agent against cancer. However, further research is necessary to determine the optimal dosage, understand its bioavailability, and assess potential side effects. This will be crucial for developing PEITC-based treatments that are both effective and safe for clinical use in cancer therapy. 相似文献
72.
Barber LB Murphy SF Verplanck PL Sandstrom MW Taylor HE Furlong ET 《Environmental science & technology》2006,40(2):475-486
Identifying the sources and impacts of organic and inorganic contaminants at the watershed scale is a complex challenge because of the multitude of processes occurring in time and space. Investigation of geochemical transformations requires a systematic evaluation of hydrologic, landscape, and anthropogenic factors. The 1160 km2 Boulder Creek Watershed in the Colorado Front Range encompasses a gradient of geology, ecotypes, climate, and urbanization. Streamflow originates primarily as snowmelt and shows substantial annual variation. Water samples were collected along a 70-km transect during spring-runoff and base-flow conditions, and analyzed for major elements, trace elements, bulk organics, organic wastewater contaminants (OWCs), and pesticides. Major-element and trace-element concentrations were low in the headwaters, increased through the urban corridor, and had a step increase downstream from the first major wastewater treatment plant (WWTP). Boron, gadolinium, and lithium were useful inorganic tracers of anthropogenic inputs. Effluent from the WWTP accounted for as much as 75% of the flow in Boulder Creek and was the largest chemical input. Under both hydrological conditions, OWCs and pesticides were detected in Boulder Creek downstream from the WWTP outfall as well as in the headwater region, and loads of anthropogenic-derived contaminants increased as basin population density increased. This report documents a suite of potential endocrine-disrupting chemicals in a reach of stream with native fish populations showing indication of endocrine disruption. 相似文献
73.
This research examined empirical evidence for a new construct, Functional Caregiving, which is a theory about mothers' caregiving of their adult children with intellectual disabilities. A sample of 108 biological mothers and primary caregivers rated survey items about their confidence to perform caregiving tasks. Rasch rating scale analysis found 61 items defined an empirical construct with three caregiving levels: Advocacy, Personal Caregiving, and Community. Results show item separation was 3.11 with high reliability, .91, and mother separation was 2.93 and reliability, .90. Both items and mothers showed adequate INFIT and OUTFIT values. Item invariance was confirmed between older and younger mothers, and principle components analysis of item residuals did not reveal any major dimensionality threats. Item decomposition analysis showed FC content theory to account for 58 percent of item calibration variance (R2 = .58, F = 42.3, p < .001). These results have important practical implications for health and social services, as well as family caregiving, interdisciplinary practices, and health policy development. 相似文献
74.
Quantification of genomic DNA is critical for many analyses in molecular biology. Current methods include optical density (OD) measurements or fluorescent enhancement but both approaches have limitations on achievable accuracy. In this study we performed an elemental analysis to quantify genomic DNA to provide an independent value for comparing the performance of four quantification methods. Specifically ICP-OES (inductively coupled plasma-optical emission spectroscopy) was used to assign a concentration value to a DNA stock solution, based on the stoichiometry of phosphorus within the molecule. Two absorbance- and two fluorescence-based methods were then used to quantify the same DNA solution using replicate analyses. The precision of each method was assessed by measurement of replicate spread (coefficient of variation) and trueness by t-test. Results showed that performance of the methods was variable, both in terms of concordance with the independent ICP-OES value and repeatability of data. While need for expensive equipment and technical expertise may preclude widespread replacement of more traditional methods for DNA quantification, use of primary methods such as ICP-OES analysis for production of accurate calibrants may increase quantitative accuracy and give greater appreciation of the true performance of current methods. 相似文献
75.
Deeken CR Bachman SL Ramshaw BJ Grant SA 《Journal of materials science. Materials in medicine》2012,23(2):537-546
Bionanocomposite scaffolds comprised of nanomaterials and the extracellular matrix (ECM) of porcine diaphragm tissue capitalizes
on the benefits of utilizing a natural ECM material, while also potentially enhancing physicomechanical properties and biocompatibility
through nanomaterials. Gold nanoparticle (AuNP) bionanocomposite scaffolds were subjected to a number of characterization
techniques to determine whether the fabrication process negatively impacted the properties of the porcine diaphragm tissue
and whether the AuNP improved the properties of the tissue. Tensile testing and differential scanning calorimetry demonstrated
that the bionanocomposite possessed improved tensile strength and thermal stability relative to natural tissue. The collagenase
assay and Fourier transform infrared spectroscopy additionally confirmed that denaturation of the collagen of the ECM did
not occur. The novel bionanocomposite scaffold possessed properties similar to commercially available scaffolds and will be
further developed for soft tissue applications such as hernia repair through in vivo studies in an animal model. 相似文献
76.
77.
Sheila Shahidi 《Journal of Natural Fibers》2017,14(2):166-174
The aim of this study was to study the influence of metal salt treatment on UV protection property of cotton fabrics. CuCl2, SbCl3, TiO2, Co3O4, SnO2, Ni(NO3)2和AgNO3 were used as metallic salts. Mentioned metallic salts were treated on cotton fabric, and the Ultraviolet Protection Factors (UPF) was examined. The morphology of fibers loaded with different metal salts was assessed by SEM. The treated cotton fabrics were then characterized by X-ray diffraction (XRD) and the crystallinity and crystals size for all samples were studied. Metal salt loaded fabrics showed better UV protection properties compared to untreated cotton fabrics. The results confirmed that metal salts have potential applications for producing ultra violet protective cotton fabric. 相似文献
78.
Delivery across skin offers many advantages compared to oral or intravenous routes of drug administration. Skin however is highly impermeable to most molecules on the basis of size, hydrophilicity, lipophilicity and charge. For this reason it is often necessary to temporarily alter the barrier properties of skin for effective administration. This can be done by applying chemical enhancers, which alter the lipid structure of the top layer of skin (the stratum corneum, SC), by applying external forces such as electric currents and ultrasounds, by bypassing the stratum corneum via minimally invasive microneedles or by using nano-delivery vehicles that can cross and deliver their payload to the deeper layers of skin. Here we present a critical summary of the latest technologies used to increase transdermal delivery. 相似文献
79.
Galesloot S Tyminski S McIntyre L Fenton T 《Revue canadienne de la pratique et de la recherche en diététique》2012,73(3):141
Purpose: The prevalence of adult-level household food insecurity was examined among clients receiving outpatient diabetes health care services. Methods: Participants were adults diagnosed with diabetes mellitus, who attended individual counselling sessions at Calgary's main clinic from January to April 2010. Clinicians were trained to administer the Household Food Security Survey Module (HFSSM), and did so with clients' assent during their scheduled sessions. Results: The prevalence of adult-level household food insecurity among 314 respondents was 15.0% (95% confidence interval [CI], 11.2 to 19.4); 6.7% (95% CI, 4.2 to 10.0) of clinic attendees were categorized as severely food insecure. The comparable rates obtained in Alberta in 2007 using the same instrument (HFSSM) were 5.6% and 1.2%, respectively. Conclusions: Household food insecurity rates among individuals with diabetes in active care are higher than rates reported in Canadian population surveys. Severe food insecurity, indicating reduced food intake and disrupted eating patterns, may affect this population's ability to follow a pattern of healthy eating necessary for effective diabetes management. This study reinforces the importance of assessing clients' inability to access food because of financial constraints, and indicates that screening with a validated measure may facilitate identification of clients at risk. 相似文献
80.
Sheila Romo-Sánchez María Arévalo-Villena Esteban García Romero Héctor L. Ramirez Ana Briones Pérez 《Food and Bioprocess Technology》2014,7(5):1381-1392
Enzyme immobilization is becoming more widely practised in biotechnology because of the advantages that this method brings. In this study, commercial β-glucosidase for aroma released in winemaking was immobilized on diverse supports (alginate–chitin, chitosan–chitin) by using different methods. It was found that the most appropriate matrix was chitosan by adsorption and reticulation. The optimal immobilization conditions were pH 3.5, immobilization time 120 min, and concentration of cross-linker glutaraldehyde 0.25 %. Stability of the immobilized enzymes was assessed, which revealed a number of advantages, such as a lower enzyme dose required for immobilization (367 times lower than the free enzyme dose recommended by the manufacturer), high stability over time, and reusability. In vitro studies of cellobiose and in vivo studies of wine and aroma precursors isolated from grape must yielded similar outcomes with respect to enzyme hydrolysis of free and immobilized proteins. 相似文献