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181.
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183.
Maternal Flaxseed Oil During Lactation Enhances Bone Development in Male Rat Pups 总被引:1,自引:0,他引:1 下载免费PDF全文
Aline D’Avila Pereira Danielle Cavalcante Ribeiro Fernanda Carvalho de Santana Aline de Sousa dos Santos Jorge Mancini-Filho Celly Cristina Alves do Nascimento-Saba Luis Guillermo Coca Velarde Carlos Alberto Soares da Costa Gilson Teles Boaventura 《Lipids》2016,51(8):923-929
Flaxseed oil is an alpha linolenic acid source important in the growth and body development stage; furthermore, this acid acts on adipose tissue and bone health. The aim of this study was to evaluate body composition, fatty acid composition, hormone profile, retroperitoneal adipocyte area and femur structure of pups at weaning, whose mothers were fed a diet containing flaxseed oil during lactation. After birth, pups were randomly assigned: control (C, n = 12) and flaxseed oil (FO, n = 12), rats whose mothers were treated with diet containing soybean or flaxseed oil. At 21 days, the pups were weaned and body mass, length, body composition, biochemical parameter, leptin, osteoprotegerin, osteocalcin, fatty acids composition, intra‐abdominal fat mass and femur structure were analyzed. FO showed (p < 0.05): higher body mass (+12 %) and length (+9 %); body fat mass (g, +45 %); bone mineral density (+8 %), bone mineral content (+55 %) and bone area (+35 %), osteocalcin (+173 %) and osteoprotegerin (+183 %). Arachidonic acid was lower (p < 0.0001), alpha‐linolenic and eicosapentaenoic were higher (p < 0.0001). Intra‐abdominal fat mass was higher (+25 %), however, the retroperitoneal adipocytes area was lower (?44 %). Femur mass (+10 %), distance between epiphyses (+4 %) and bone mineral density (+13 %) were higher. The study demonstrates that adequate flaxseed oil content during a lactation diet plays an important role in the development of pups. 相似文献
184.
Roseli de Souza Santos da Costa Flavia da Silva Santos Daniela de Barros Mucci Tânia Vignuda de Souza Fátima Lucia de Carvalho Sardinha Célia Regina Moutinho de Miranda Chaves Maria das Graças Tavares do Carmo 《Lipids》2016,51(12):1363-1373
The purpose of this study was to investigate the trans fatty acids (TFA) content and distribution in colostrum, mature milk, and diet of adolescent mothers, after TFA declaration in food labels became mandatory in Brazil. Participants were healthy adolescents (n 54, 15–19 years, 1–90 days postpartum) practicing exclusive breastfeeding. Milk samples were collected 3 days after delivery (colostrum) and in the third month postpartum (mature milk) by hand expression. The fatty acid composition of the milk samples was determined by gas chromatography. TFA intake corresponded to 1.23 % of total energy value. Total 18:2 TFA accounted for less than 0.5 % of the energy intake. The amount of total 18:1 TFA (mean ± SEM) was 1.9 % ± 0.14 in colostrum and 1.5 % ± 0.2 in mature milk. The total content of n‐3 PUFA was inversely correlated with the total content of 18:1 TFA in colostrum. Both in colostrum and in mature milk, vaccenic acid (11t‐18:1) was found to be the most abundant 18:1 trans isomer, followed by elaidic acid (9t‐18:1), whereas rumenic acid (9c,11t‐18:2 CLA) was the predominant 18:2 trans isomer. In conclusion, the levels of TFA of industrial sources found in the mother's diet and breast milk (colostrum and mature milk) showed a decrease in relation to those observed in studies conducted prior to the TFA labeling resolution in Brazil. However, the current low intake levels of n‐3 LCPUFA and DHA content in the milk of lactating adolescents may be insufficient for supporting adequate neurological development of the infants. 相似文献
185.
Effects of drilling parameters and aspect ratios on delamination and surface roughness of lignocellulosic HFRP composite laminates 下载免费PDF全文
Sikiru Oluwarotimi Ismail Hom Nath Dhakal Eric Dimla Johnny Beaugrand Ivan Popov 《应用聚合物科学杂志》2016,133(7)
Hemp fibre‐reinforced polycaprolactone (HFRP) composite has inherent good mechanical properties and benefits which include remarkably high specific strength and modulus, low density, and renewability. No doubt, these properties have attracted wider applications of HFRP composite in engineering applications. This paper presents an investigation on the influence of drilling parameters and fibre aspect ratios, AR (0, 19, 26, 30, and 38) on delamination damage factor and surface roughness of HFRP composite laminates utilising high speed steel twist drills under dry machining condition. Taguchi's technique was used in the design of experiment. The results obtained show that increase in cutting speed reduces delamination factor and surface roughness of drilled holes, whereas increase in feed rate causes increase in both delamination factor and surface roughness. Feed rate and cutting speed had the greatest influence on delamination and surface roughness respectively when compared with aspect ratio, while an increase in fibre aspect ratios leads to a significant increase in both delamination factor and surface roughness. The optimum results occurred at cutting speed and feed rate (drilling parameters) of 20 mm/min and 0.10 mm/rev, respectively, when drilling sample of AR 19. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42879. 相似文献
186.
Multivalent Interactions between an Aromatic Helical Foldamer and a DNA G‐Quadruplex in the Solid State 下载免费PDF全文
Dr. Pradeep K. Mandal Dr. Benoît Baptiste Dr. Béatrice Langlois d'Estaintot Dr. Brice Kauffmann Dr. Ivan Huc 《Chembiochem : a European journal of chemical biology》2016,17(20):1911-1914
Quinoline‐based oligoamide foldamers have been identified as a potent class of ligands for G‐quadruplex DNA. Their helical structure is thought to target G‐quadruplex loops or grooves and not G‐tetrads. We report a co‐crystal structure of the antiparallel hairpin dimeric DNA G‐quadruplex (G4T4G4)2 with tetramer 1 —a helically folded oligo‐quinolinecarboxamide bearing cationic side chains—that is consistent with this hypothesis. Multivalent foldamer–DNA interactions that modify the packing of (G4T4G4)2 in the solid state are observed. 相似文献
187.
Ultrastructure of the digestive tract in neotropical carnivorous catfish Hemisorubim platyrhynchos (Valenciennes, 1840) (Siluriformes,Pimelodidae) 下载免费PDF全文
188.
Tubular dentin sealer penetration after different final irrigation protocols: A confocal laser scanning microscopy study 下载免费PDF全文
Ricardo Machado Alessandra Timponi Goes Cruz Bianca Marques de Mattos de Araujo Adriane Antoniw Klemz Hellen Pontes Klug Ulisses Xavier da Silva Neto 《Microscopy research and technique》2018,81(6):649-654
The aim of this study was to evaluate tubular dentin sealer penetration, comparing different final irrigation protocols using a conventional needle (CONV), EndoActivator system (EAS), EndoVac system (EVS), and ultrasound (PUI). Initially, fifty‐two first maxillary molars with a single canal in the palatal root, without abrupt curvatures, resorptive processes, or previous endodontic treatment were selected for this study. Then, the crowns were sectioned to obtain palatal roots 15 mm in length. The root canals were prepared with the ProTaper Universal System and irrigated with 5% NaOCl. Afterwards, the specimens were divided into four groups (n. 13), according to the final irrigation protocol: CONV, EAS, EVS, and PUI. After filling, slices at 3 mm and 5 mm from the apex were obtained for analysis by confocal laser scanning microscopy. Two‐way comparisons between the groups and the levels were performed with Games Howell's test (p < .05). Tubular dentin sealer penetration was higher at 5 mm compared with 3 mm from the apex (p < .05). The EAS group showed a higher percentage of tubular dentin sealer penetration, compared with the CONV group, at both levels. At 3 mm, there was no statistically significant difference among EAS, EVS, and PUI; however, these groups showed better performance, compared with the CONV group. At 5 mm, there was no statistically significant difference between the EAS and EVS groups, but both showed higher sealer penetration than the PUI group (p < .05). The EAS and EVS groups achieved better degrees of tubular dentin sealer penetration, compared with the other groups. 相似文献
189.
Liana Franco Padilha Cristine Carretoni Ferreira Fabricio Machado Márcio Nele José Carlos Pinto 《应用聚合物科学杂志》2014,131(9)
In this work, NIRS is employed to provide compositions of α‐olefin copolymers, allowing for evaluation of the effects of certain key process variables on the final NIR spectral responses of obtained polymer materials. This work also introduces a new temperature programmed analytical technique, which combines NIRS measurements with partial fractionation of α‐olefin copolymers. The new proposed technique can be used for evaluation of polyolefin compositions, as presented here for poly(propene/1‐butene) copolymers. Besides, preliminary results obtained from thermal fractionation experiments indicate that this new proposed experimental technique can be employed for characterization of comonomer sequence distributions of α‐olefin copolymers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40127. 相似文献
190.
Chayene G. Anchieta Daniela Sallet Edson L. Foletto Syllos S. da Silva Osvaldo Chiavone-Filho Claudio A.O. do Nascimento 《Ceramics International》2014
Ternary zinc spinel oxides such as Zn2SnO4, ZnAl2O4 and ZnFe2O4 were synthesized and characterized, and their activities in the photodegradation of phenol molecules were investigated. Zn2SnO4, ZnAl2O4 and ZnFe2O4 powders were synthesized by hydrothermal, metal–chitosan complexation and solvothermal routes, respectively. The face-centered cubic spinel structure of each material was confirmed by powder X-ray diffractometry (XRD) and its porous structure by N2 adsorption–desorption isotherms. The characterization of spinels was complemented with Fourier transform infrared spectroscopy (FTIR) and X-rays fluorescence (XRF), revealing the formation of spinel structures with high purity. The photocatalytic activity in the degradation of phenol was observed only with Zn2SnO4 oxide. Mineralization degree of phenol molecules by Zn2SnO4 photocatalyst determined by total organic carbon analysis (TOC) reached 80% at 360 min under sunlight. 相似文献