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51.
Acyl CoA:cholesterol acyltransferase (EC2.3.1.26, ACAT), responsible for intracellular esterification of cholesterol, may
play an important role in cholesterol trafficking within the cell, and thus, in maintenance of cellular cholesterol homeostasis.
Bile acids are potential regulators of cholesterol trafficking in the liver. Therefore, the effect of bile salts on hepatic
ACAT activity was studied in the perfused rat liver. ACAT activity was increased after liver perfusion with either taurocholate
or taurochenodeoxycholate. However, addition of these bile salts at physiological concentrationsin vitro had little effect on microsomal ACAT activity. The increase in hepatic ACAT activity due to perfusion with bile salts was
accompanied by reduced accumulation of very low density lipoprotein cholesterol in the perfusate, but there was no effect
on 3-hydroxy-3-methylglutaryl-CoA reductase activity. Hepatic ACAT activity was decreased after bile diversion for four hours
in the intact animal. This treatment had no statistically significant effect on 3-hydroxy-3-methylglutaryl-CoA reductase activity.
These data suggest that bile salts induce changes in hepatic compartmentation and traffic of cholesterol within the hepatocyte
accompanied by response of ACAT activity to maintain cellular cholesterol homeostasis. 相似文献
52.
Collagenous material was obtained from chicken feet skins and tendons, defatted with ethylic ether and treated with 0.05 M and 0.6 M NaCl solutions. Part of the material was dried at 35 degrees C in a forced air convection oven and another was freeze-dried. The air dried material had 77.2 g/100 g of collagen and the freeze-dried material 76.7 g/100 g. Both dehydrated materials showed the same behaviour for gel formation and cold water holding capacity. The material air dried had higher emulsifying capacity than the freeze-dried one. The collagen of freeze-dried material had higher solubility in 0.5 M acetic acid and water at 70 degrees C than air dried material. Gel strength, emulsion stability and water holding capacity at 60 degrees C were higher for freeze-dried material. The results indicate the potential use of these materials as functional ingredients in meat products. 相似文献
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54.
Alfaro Mde J Alvarez I El Khor S de Padilla FC 《Archivos latinoamericanos de nutrición》2004,54(2):223-228
The functional properties of Caryodendron orinocense protein product were investigated and compared with those of soybean (Glycina maxima). The product protein content was 24.47 g/100 g (Nx6.25). Solubility increased at both sides of the isoelectric point (pH 4.0) and with increased NaCl concentration up to 0.5M. Compared with soybean flour (50% protein), the protein product exhibited higher water and oil absorption, but lower emulsifying activity, emulsion stability, foaming capacity, and foam stability, the last one increase at higher pH. Emulsifying activity, foaming capacity, and foam stability were ionic strength dependent. C. orinocense protein product increased its emulsifying activity steadily from 0.05M to 0.75M NaCl, while it remained almost constant for soybean flour. Foaming capacity increased drastically at pH 10. The minimum time and concentration to form a gel was 20% in 4 min and 10% in 8 min for the Caryodendron protein product and soybean flour, respectively. The bulk density was 0.5056+/-0.0041 g/mL. 相似文献
55.
The crosslinked poly[3‐(methacryloylamino)propyl]dimethyl(3‐sulfopropyl)ammonium hydroxide], P(MAPDSA), and poly[3‐(methacryloylamino)propyl]dimethyl(3‐sulfopropyl)ammonium hydroxide‐co‐acrylic acid], P(MAPDSA‐co‐AA), were synthesized by radical polymerization. The resins were completely insoluble in water. Due to the lower metal ion retention of P(MAPDSA), the metal ions investigated under competitive and noncompetitive conditions for Cu(II), Cd(II), Hg(II), Zn(II), Pb(II), and Cr(III) ions by batch and column equilibrium procedures were carried out only for P(MAPDA‐co‐AA), particularly for Hg(II). The resin–Hg(II) ion equilibrium was achieved before 15 min. The resin showed a maximum retention capacity value for Hg(II) at pH 2 of 1.89 meq/g. The resin showed a high selectivity to Hg(II) ions. The recovery of the resin was investigated at 25°C with different concentrations of HNO3 and HClO4. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 525–530, 2005 相似文献
56.
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The metal‐ion uptake behavior of the chelating resin poly([(3‐(methacryloylamino)propyl] trimethyl ammonium chloride‐co‐4‐vinyl pyridine) has been investigated. The resin is obtained by radical copolymerization in a yield of 99.6%. The hydrophilic resin shows a high retention capacity and selectivity toward Hg(II) ions in the presence of Cu(II), Pb(II), Cd(II), Zn(II), and Cr(III) ions. A retention of Hg(II) higher than 99% is observed after 5 min. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2595–2599, 2002 相似文献
58.
Baldassarri Sandra Passerino Liliana Ramis Silvia Riquelme Inma Perales Francisco J. 《Universal Access in the Information Society》2021,20(2):239-254
Universal Access in the Information Society - Technology and videogames have been proven as motivating tools for working attention and complex communication skills, especially in children with... 相似文献
59.
Definition of the problem Ethics cafés in long-term geriatric care are considered as ethical education. They allow the participants to have an open discourse in a casual setting about moral issues related to daily work. In the literature, various characteristics are attributed to ethics cafés, e.g., improving analytical skills and communication, increasing ethical sensitivity and authority for making decisions. These characteristics primarily result from theory-based models. Arguments The goal of this study is the empirical investigation of the effectiveness of ethics cafés in the Nursing Homes Mattenhof–Irchelpark, Zurich. Furthermore, the study examined whether the subjective evaluation of characteristics of nurses and other professional groups are different. To capture the characteristics, a questionnaire was constructed in which the participants rated 16 statements during the survey period. A 5-point Likert scale was used for the analysis. One subgroup distinguished between “nursing staff” and “non-nursing staff”. Conclusion The postulated characteristics were confirmed with a very high approval. Therefore, the ethics cafés provide important input which enable the staff to analyze more clearly in difficult situations or to let them decide ethically in a more sensitive manner and to justify decisions made. The interdisciplinary approach supports an understanding of the views and arguments among the various areas and hierarchies. The differences between the two professionals groups are partially highly significant. It can be noted that the assigned characteristics in the questionnaire are generally perceived stronger and more significantly by the nursing staff. Therefore, a distinction must be made when interpreting the results of this study concerning the participants. 相似文献
60.
Pamela Sierra Garcia Juliana Aristéia de Lima Carlos Henrique Scuracchio Sandra Andrea Cruz 《应用聚合物科学杂志》2021,138(29):50703
This work aims to investigate the effect of adding vulcanized or partially devulcanized rubbers on recycled polypropylene (PPr), considering thermomechanical and morphological properties. The study proposes to better understand how structural changes underwent by rubber (after the devulcanization) contributed to improving the mechanical properties of the PPr. The PPr/rubber blends were prepared by a co-rotating twin-screw extruder and then were injected. The blends composed of the most devulcanized rubbers by microwaves with refined microstructure showed higher values of elongation at break and toughness. Data showed that the devulcanization process applied to the rubber interfered positively in its adhesion to the PPr. Data from dynamic mechanical analysis and atomic force microscopy indicated that the most devulcanized rubbers presented an interface more connected to PPr. These chemical interactions possibly impacted the mechanical properties of the PPr. Moreover, dilatation processes favored the fracture mechanisms of the PPr when rubber was added to it. 相似文献