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71.
Alfaia CM Castro ML Martins SI Portugal AP Alves SP Fontes CM Bessa RJ Prates JA 《Meat science》2007,75(1):44-52
This paper describes the influence of slaughter season on lipid content, fatty acid composition, conjugated linoleic acid (CLA) isomeric profile and nutritional value of fat in Barrosã veal from calves reared according to the specifications of the Protected Designation of Origin (PDO). Barrosã purebred calves (n = 27) were raised in a traditional production system and slaughtered in early autumn (October) and late spring (June). Barrosã-PDO veal only presented seasonal differences in the levels of some minor fatty acids and CLA isomers, as well as in the PUFA/SFA ratio. Based on the analysed grass intake indicators, it was shown that veal-PDO has similar values to pasture-fed cattle for both slaughter seasons. From a human nutrition perspective, intramuscular fat in Barrosã-PDO veal has a high nutritional value throughout the year, since CLA contents and the percentages of the c9,t11 isomer are relatively high, and the n − 6/n − 3 ratios are within the recommended values for the human diet. 相似文献
72.
Roberta Roesler Luciana G. Malta Luciana C. Carrasco Gláucia Pastore 《Journal of food science》2006,71(2):C102-C107
Annona crassiflora, known commonly as araticum, is an exotic tropical fruit consumed mainly by native people of the Brazilian Cerrado (2nd biggest biome of Brazil). In this study, pulp, seed, and peel of slight ripe and overripe fruits were extracted using ethanol and water. The extracts showed high content of total phenols and were screening for their potential as antioxidants using the in vitro model 1,1‐ dipheniyl‐2‐picryl hydrazyl (DPPH). The ethanol extracts of peel and seeds showed IC50 of 48.82 μg/mL and 31.14 μg/mL, respectively, for the slightly ripe fruits. As the ethanolic fractions of araticum showed the highest antioxidant activity, they were selected for testing of its effect on lipid peroxidation. The ethanolic extracts of slightly ripe fruits showed IC50 of 4.44 μg/mL, 1.72 μg/mL, and 8.62 μg/mL for the peel, seed, and pulp, respectively. This is the 1st report on the antioxidant properties of the extracts of araticum. Owing to these properties, the studies can be further extending to exploit them for their possible application as natural antioxidant for cosmetic, supplements, and functional ingredients for food products. 相似文献
73.
Maurizio Penco Luciana Sartore Fabio Bignotti Stefania Della Sciucca Vittorio Ferrari Paolo Crescini Salvatore D'Antone 《应用聚合物科学杂志》2004,91(3):1816-1821
The aim of this work was the development of materials to be used in the field of gas sensing for the detection of organic vapors. Conductive sensors were prepared with carbon black filled blends of poly(vinyl chloride) and diol‐terminated poly(?‐caprolactone), an oligomeric plasticizer. For comparison, blends with di(2‐ethylhexyl)phthalate, a traditional low‐molecular‐weight plasticizer, were also prepared. All sensors were tested upon exposure to different organic vapors. In general, the plasticizer content affected the response rates of the sensors, and a linear variation of the relative resistance with the analyte concentration was observed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1816–1821, 2004 相似文献
74.
75.
This paper presents a new mathematical model that can be used to predict the solidification rate and the temperature distribution during the unidirectional solidification of metals n molds cooled by fluids such as air and water. The model differs from other analytical methods presented in the literature in the sense that it is more general in application and easier to manipulate, while retaining the advantage of convenience over numerical techniques. The proposed model permits the measurement of the Newtonian heat transfer coefficient at the metal/mold interface. In order to verify the applicability to air cooled molds, the model is compared with experimental results in the literature for the cases of lead, tin and lead-tin eutectic. Finally, the case of water cooled molds is examined, the model being compared with experimental results obtained in this work for lead and aluminum. 相似文献
76.
Luciano Favretto Luciana Gabrielli Favretto 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,179(3):201-204
Summary The concentration of Cd, Hg and Pb in the soft part of mussels has been studied by means of bi-and multi-variate statistical approaches. In particular, the principal component analysis has been applied to study the association among these toxic metals in mussels sampled from the gulf of Trieste, which is a critical area as far as mercury pollution is concerned.
Mehrdimensionale Analyse der Daten einiger xenobiotischer Spurenmetalle in Miesmuscheln aus dem Golf von Triest
Zusammenfassung Der Gehalt von Cd, Hg und Pb in Miesmuschelfleisch wurde nach einer statistischen mehrdimensionalen Analyse untersucht. Besonders wurde die Hauptkomponentenanalyse zum Studium der Assoziationen dieser toxischen Metalle in Miesmuscheln angewandt. Die Miesmuschelproben stammten aus dem Golf von Triest, ein kritisches Gebiet für Quecksilberverunreinigungen.相似文献
77.
MK Nolan L Jankowska M Prisco S Xu MA Guvakova E Surmacz 《Canadian Metallurgical Quarterly》1997,72(5):828-834
Several polypeptide growth factors stimulate breast cancer growth and may be involved in tumor progression. However, the relative importance of diverse growth factor signaling pathways in the development and maintenance of the neoplastic phenotype is largely unknown. The activation of such growth factor receptors as the insulin-like growth factor I receptor (IGF-I R), erbB-type receptors (erbB Rs) and FGF receptors (FGF Rs) controls the phenotype of a model breast cancer cell line MCF-7. To evaluate the function of 2 post-receptor signaling molecules, insulin receptor substrate-1 (IRS-1) (a major substrate of the IGF-IR) and SHC (a common substrate of tyrosine kinase receptors), we developed several MCF-7-derived cell clones in which the synthesis of either IRS-1 or SHC was blocked by antisense RNA. In MCF-7 cells, down-regulation of IRS-1 by 80-85% strongly suppressed anchorage-dependent and -independent growth and induced apoptotic cell death under growth factor- and estrogen-reduced conditions. The reduction of SHC levels by approximately 50% resulted in the inhibition of monolayer and anchorage-independent growth but did not decrease cell survival. Importantly, cell aggregation and the ability of cells to survive on the extracellular matrix were inhibited in MCF-7/anti-SHC clones, but not in MCF-7/anti-IRS-1 clones. Cell motility toward IGF was not attenuated in any of the tested cell lines, but motility toward EGF was decreased in MCF-7/anti-SHC clones. Our results suggest that in MCF-7 cells: 1) both IRS-1 and SHC are implicated in the control of monolayer and anchorage-independent growth; 2) IRS-1 is critical to support cell survival; 3) SHC is involved in EGF-dependent motility; and 4) normal levels of SHC, but not IRS-1, are necessary for the formation and maintenance of cell-cell interactions. 相似文献
78.
Arcamone N Lucini C Borzacchiello G Castaldo L Gargiulo G De Girolamo P 《Microscopy research and technique》2005,66(1):17-24
By means of immunochemistry and immunohistochemistry, we investigated in the kidney of freshwater and marine teleostean species for the presence and localization of three neurotrophins: nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin (NT)-3. In both species studied, NGF-like and NT-3-like immunoreactivity were present in the kidney with different distribution patterns, while BDNF-like immunoreactivity was never detected. In goldfish, NGF-like and NT-3-like immunoreactivity were identified extensively in cells along part of the arterial branches adjacent to the afferent arterioles. In scorpion fish, NGF-like and NT-3-like immunoreactive cells were observed both on afferent arterioles and on adjacent secondary branches derived from renal arteries. No immunoreactivity was detected in other renal structures. A staining pattern of immunoreactivity similar to that obtained for NGF and NT-3 was detected utilizing S100 antibody as a juxtaglomerular (JG) cell marker. Double immunolabellings NGF/S100 and NT-3/S100 evidenced the coexistence of neurotrophin-like proteins and S100-like protein in the same immunoreactive cells, thus identifying them as juxtaglomerular cells. Western blot analysis revealed the presence of molecules immunoreactive to NGF and NT-3, whose molecular weights were very similar to those of the corresponding mammalian neurotrophins. These findings extend the presence and distribution of NGF-like and NT-3-like IR in the kidney to teleost species, suggesting a probable participation of these proteins in the renal functions of freshwater and marine teleosts. 相似文献
79.
Structures and substructures in the chill zone have been studied in Al-Cu alloys as a function of the following solidification
conditions at the substrate chill: a) heat sink capacity; b) surface microprofile; c) nature of the liquid metal fluid flow
as it makes substrate contact. The parameters taken in account both experimentally and analytically are: heat transfer coefficient
of the metal/mold interface, surface rugosity of the mold walls, and the Reynolds number of the liquid metal fluid flow. The
results obtained show definite correlations between the structural characteristics of the chill zone and the values of the
studied parameters. 相似文献
80.
A. M. M. Nazar N. L. Cupini M. Prates G. J. Davies 《Metallurgical and Materials Transactions B》1979,10(2):203-210
Experiments are described in which an effervescent mold coating containing hexachloroethane has been used to promote the dynamic
grain refinement of commercial purity aluminum ingots. The influence of the amount of hexa chloroethane in the mold coating,
the degree of superheat of the cast metal and the nature of the mold material was assessed. Comparison has been made with
unrefined ingots and with ingots grain refined using conventional inoculation procedures. It is concluded that low levels
of hexa chloroethane (10 to 20 wt pct in the mold coating) can produce effective refinement provided conditions exist favorable
for the survival of dendrite fragments or nucleating particles generated by the remelting associated with turbulence in the
liquid or chemical and/or mechanical interactions between the effervescing gas and the mold coating. The effectiveness of
refinement is enhanced by high rates of heat transfer and low pouring superheats.
Visiting Professor in the Department of Mechanical Engineering, State University of Campinas. 相似文献