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Sambasivam Manikandaselvi Vellingiri Vadivel Pemaiah Brindha 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2016,24(3):508
In the present, work chemical composition and nutritional value of aerial parts of Cassia occidentalis L. was studied. The aerial parts of C. occidentalis possess favorable physicochemical properties with good nutritional value, such as high energy value, crude fibers, and vitamin levels. The X-ray fluorescence spectrophotometry data revealed that the sample is rich in minerals, especially in Fe, Ca, K, and Mn. Further, minerals such as Mg, Zn, Cu, Na, P, and S are present in good amount and depicted the nutritional value of the selected material. The plant sample is rich in phytochemicals such as flavonoids, alkaloids, lignin, tannins, and phenols. The presence of phytochemical constituents was confirmed by gas chromatography–mass spectrometry profile and high-performance thin layer chromatography fingerprinting techniques. The findings stimulate the on-farm cultivation of C. occidentalis on a large scale to relieve the iron deficiency in local community, and it can be used as a dietary supplement to treat anemia. 相似文献
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《Dental materials》2019,35(11):1523-1531
ObjectivesThiourethane oligomers have been shown to increase the fracture toughness and reduce the polymerization stress of methacrylate-based materials. However, network formation has not been elucidated in these materials yet. The aim of this study was to evaluate how the addition of a thiourethane oligomer (TU) influences the sol/gel composition and network structure of methacrylate-based materials using dynamic mechanical analysis and extraction methods.Materials and methodsBisGMA/TEGDMA at systematically varied mass ratios (20/80 to 80/20 wt%) were mixed with pre-polymerized thiourethane oligomers at 0 (control) or 20 wt%, synthesized by combining pentaerythritol tetra-3-mercaptopropionate with dicyclohexylmethane 4,4⿲-Diisocyanate, at 1:2 isocyanate:thiol. 0.1 wt% of 2,2-Dimethoxy-2-phenylacetophenone was added as the photoinitiator and 0.3 wt% of 2,6-di-tert-butyl-4-methylphenol was added as a free radical inhibitor. Disk specimens (0.8 ÿ 10 mm in diameter, n = 3) were photoactivated at 270 mW/ (320500 nm) for 1 min. The degree of conversion (DC) was measured in near-IR (˿6165 cm1). Specimens were immersed in two different solvents (water for 7 days or dicholoromethane for 48 h). Water sorption (WS) and solubility (SL) were obtained according to ISO 4049. The leachates for both solutions were analyzed with 1H-NMR (400 MHz, CDCL3). Bar specimens (1 ÿ 3 ÿ 25 mm, photocured and then post-processed at 180 °C for 8 h to DC > 95%) were subjected to dynamic mechanical analysis (30 to 230 °C) to obtain glass transition temperature (Tg), tan delta curves and crosslinking density (ν). Data was analyzed with two-way ANOVA/Tukeys test (95%).ResultsIn general, the presence of TU increased the overall conversion. The WS was similar for all groups, but the SL decreased by 2-fold with the addition of the TU oligomer for all compositions, except BisGMA/TEGDMA 80/20. The BisGMA concentration of the leachates increased with increasing BisGMA in the initial mixture, and with the presence of thiourethane. This compositional drift of the gel with the presence of TU was attributed to the preferential dissolution of TEGDMA into the TU network. Tg and ν decreased with the addition of TU, as expected. The addition of TU produced more homogeneous networks, as evidenced by narrower breadth of the tan delta curve.ConclusionThe addition of TU affected the composition of the sol/gel in crosslinked networks, which were more homogeneous and presented 2-fold less potentially toxic leachates than the methacrylate controls.Clinical significanceThe addition of TU may produce less cytotoxic materials based on the increased conversion and reduced amount of unreacted extractables from its network after water storage. 相似文献
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Research evidence indicates that approximately 10 h a week is a sufficient intensity for short-term day treatment programmes for patients with personality disorders. In this article, we discuss which therapeutic components should be included in such a programme. Relevant research and clinical literature are reviewed. The fit between the therapeutic components and the programme as a whole is discussed according to: 1) scientific evidence of the effectiveness of the therapeutic components, 2) a sound theoretical rationale, 3) evidence of user satisfaction among patients, 4) clinical experiences of staff, 5) comprehensiveness and consistency, and 6) available therapeutic skills and resources. We advocate an 11-h treatment programme comprising small group psychotherapy, art group therapy, large group psychotherapy, cognitive group therapy, problem-solving group therapy and optional adjuncts (cognitive behavioural group therapy) for patients with additional anxiety and eating disorders. 相似文献