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11.
This study examined factors that influence body image and strategies to either lose weight or increase muscle among children. Participants were 237 boys and 270 girls. Body mass index (BMI), body dissatisfaction, cognitions and behaviors to both lose weight and increase muscles, as well as self-esteem and positive and negative affect, were evaluated. Self-esteem was associated with body satisfaction, positive affect predicted strategies to lose weight and increase muscles, and negative affect predicted body dissatisfaction and cognitions to lose weight and increase muscles. Boys were more likely to focus on changing muscles. Respondents with higher BMIs were more focused on losing weight but not muscle. The discussion focuses on health risk behaviors related to eating and exercise among children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
J R?bin? J Natunen R Niemel? H Salminen K Ilves O Aitio H Maaheimo J Helin O Renkonen 《Canadian Metallurgical Quarterly》1997,305(3-4):491-499
By using two different reaction pathways, we generated enzymatically three sialylated and site-specifically alpha 1-3-fucosylated polylactosamines. Two of these are isomeric hexasaccharides Neu5Ac(alpha 2-3)Gal(beta 1-4)GlcNAc(beta 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)] GlcNAc and Neu5Ac(alpha 2-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)Gal(beta 1-4) GlcNAc, containing epitopes that correspond to VIM-2 and sialyl Lewis (x), respectively. The third one, nonasaccharide Neu5Ac(alpha 2-3)Gal(beta 1-4)GlcNAc(beta 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)] GlcNAc(beta 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc, is a sialylated and internally difucosylated derivative of a trimeric N-acetyllactosamine. All three oligosaccharides have one fucose-free N-acetyllactosaminyl unit and can be used as acceptors for recombinant alpha 1-3-fucosyltransferases in determining the biosynthesis pathways leading to polyfucosylated selectin ligands. 相似文献
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The aim of the present study was to characterise the thermal properties of connective tissue in loose structured porcine SM muscles in comparison to normal looking SM muscles and to see whether the meat quality traits were related to the properties of connective tissue. Samples from the muscles with loose structure and light colour were selected by visual assessment and normal looking SM muscles were used as a control (n = 25 loose structured + 25 control). The loose structured muscles had lower ultimate pH (pHu) than the control muscles. The onset and peak temperatures of thermal shrinkage of intramuscular connective tissue (To and Tp, respectively) in loose structured muscles were similar to those of control muscles when the full set of data (25 loose structured + 25 control) were analysed. When the To and Tp data from muscles the exhibiting ten lowest and ten highest pHu values were analysed, the low pHu muscles (all classified as loose structured) had lower To and Tp than the high pHu muscles (all classified as control) (p < 0.05). Drip loss of loose structured SM muscles (11.1%) was dramatically higher than that of control muscles (3.9%). Collagen content and collagen solubility were similar in loose structured and control muscles. It seemed that changes in the properties of intramuscular connective tissue were more easier found in porcine SM muscles with low pHu than in SM muscles with high pHu. 相似文献
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This analysis of HF/E literature on preferences for text entry distills the findings to guide designers in applying optimum solutions for devices such as PDAs and cell phones. 相似文献
16.
The results from ethene hydroformylation at 173°C showed that a Co(acac)3/SiO2 catalyst prepared from Co(acac)3 precursor by gas‐phase deposition was three times as active as a catalyst prepared by impregnation from cobalt nitrate, but
oxo‐selectivities were similar. The high propanal selectivities on the Co(acac)3/SiO2 seem to be related to the presence of highly dispersed active sites favouring CO insertion. As dispersion is decreased from
23 to 8% due to increasing metal content (from 5 to 16 wt%), oxo‐selectivity decreased from 39 to 25%. The activity of Co(acac)3/SiO2 remained unchanged during 68 h on stream. The gas‐phase deposition technique described here is a promising method for the
preparation of active, selective and stable heterogeneous hydroformylation catalysts.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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An effective wet digestion procedure for the determination of total iodine contents in milk powder samples was developed utilizing a high-pressure asher technique. The optimized method based on a two-stage digestion procedure. In the first stage, 500 mg samples were digested at 300 °C for 2 h using 15.2 mol L?1 HNO3 (5 mL) and 30 % H2O2 (3 mL). After the first digestion stage, digestion vessels were allowed to cool down and 1.2 mL of 20 % (w/v) Na2S2O8 solution was added as an additional oxidizing agent to the samples. After that, the vessels were closed, and they were heated at 100 °C for 30 min, resulting in clear and colorless sample solutions. Iodine concentrations in the digested samples were measured with inductively coupled plasma mass spectrometry. The accuracy of the optimized method was confirmed by analyzing milk powder reference material (BCR-151, milk powder). The obtained value for iodine (5.29?±?0.37 mg kg?1, n?=?6) was in good agreement with the certified value (5.35?±?0.14 mg kg?1). Furthermore, the results obtained for reference material showed that the developed method can be applied also for the determination of other elements, e.g., copper, iron, and lead in the digested milk powder samples. 相似文献
19.
The aim of this study was to investigate the buffering capacity (BC) of five porcine muscles. The pH of muscles with zero lactate was also estimated. The BC was calculated on the basis of the amount of lactate accumulating in the muscle between two sampling times and the simultaneous pH decline. Two muscle samples were obtained from each muscle (n=13–36): one as soon as possible after slaughter and the other 24 h post-mortem. The BCs (mmol lactate/(pH kg)) were in the light gluteus superficialis, longissimus dorsi and semimembranosus muscles 48.3 ± 8.8, 48.6 ± 9.2 and 46.8 ± 13.0, and in the dark infraspinatus and masseter muscles 45.3 ± 13.1 and 32.0 ± 11.5, respectively. The dark masseter muscle differed significantly from the other muscles studied (p<0.01). The estimated pH values of muscles with zero lactate were in the gluteus, longissimus dorsi, semimembranosus muscles 7.14 ± 0.06; 7.18 ± 0.06; 7.38 ± 0.08, and in the infraspinatus and masseter muscles 6.87 ± 0.07; 7.03 ± 0.08, respectively. It was suggested since lactate is continuously formed in the muscles, the resting pH of living light and dark muscles may, however, be the same. The approach used in this study to determine the BC resulted in values which are close to values previously reported in the literature (measured by using titration curves). 相似文献
20.
Marita Wittkowski Werner Baltes Wolfhard Krönert und Rudolf Weber 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1983,177(6):447-453
Zusammenfassung Es wird eine Phasenumkehr-HPLC-Methode beschrieben, die es gestattet, dieAlternaria-Toxine Alternariol (AOH), Alternariolmonomethylether (AME), Altenuen (ALT) und Altertoxin I (ATX-I) in Obst- und Gemüseerzeugnissen mit guter Empfindlichkeit zu bestimmen. Die Ergebnisse werden dünnschichtchromatographisch abgesichert. Sie wurde an ca. 50 Handelsprodukten Bowie an ca. 20 verschimmelten Früchten erprobt. Keines der Handelsprodukte war mit den o. g. Mykotoxinen kontaminiert, während zwei der verschimmelten Proben (Äpfel) 160 ppb AOH, bzw. 250 ppb AME enthielten.
Determination of alternaria toxins in fruit and vegetable products
Summary A reverse phase HPLC method for the determination of theAlternaria mycotoxins alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT) and altertoxin I (ATX-I) in fruit and vegetable products is described. The procedure has good sensitivity. The results are corroborated by TLC. About 50 commercial products and about 20 mouldy fruits were analysed. None of the commercial products was contaminated with the toxins whereas two of the mouldy samples (apples) contained 160 ppb AOH respectively 250 ppb AME.相似文献