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41.
de Moreno LA Vidal A Huerta-Sánchez D Navas Y Uzcátegui-Bracho S Huerta-Leidenz N 《Archivos latinoamericanos de nutrición》2000,50(4):409-415
Raw meat samples from iguana, poultry and beef cattle specimens were used to compare proximal (g/100 g) and mineral (mg/100 g) composition. Iguana meat was obtained by dissecting whole specimens (Iguana iguana) captured at a ranch (n = 20). Thighs and breasts were separated from broiler (either chilled or frozen) carcasses (n = 20), and deboned to represent chicken meat samples, whereas 2.5-cm-thick longissimus (ribeyes) steaks were removed from carcasses and frozen to represent beef of several breed types (n = 20). The one-way analysis of variance performed by the least squares method (LS Means) showed specie affected significantly (p > 0.05) all composition variables under study. Moisture content did not differ between iguana and chicken meats (74.7 y 74.9%, respectively) whereas beef samples had the lowest water content (73%) (p < 0.01). LS means for protein content showed beef samples (22.3%) were highest (p < 0.05) in this nutrient, iguana meat being intermediate (20.8%). Chicken meat presented the highest amount of total lipids (7.75 +/- 0.20 g/100 g) (p < 0.01) followed by iguana (3.49 +/- 0.12 g/100 g) and beef (2.57 +/- 0.20 g/100 g). Ash and most individual minerals were more concentrated in iguana meat, except for K and Zn that were more abundant in beef samples. Non-significant differences in Mg, Na, Cu or Mn contents were detected between chicken and beef samples. It was concluded that iguana meat could be an alternate source of protein and minerals as compared to those of traditional meat species. 相似文献
42.
The use of steady-state free precession nuclear magnetic resonance (NMR) for quantitative analysis in low magnetic field is investigated and shown to exhibit substantial advantages compared to more conventional NMR methods. With only minor additional requirements, the technique permits a considerable increase in signal-to-noise ratio for a given acquisition time. The experimental conditions needed for implementation and optimization of the acquisition parameters are explored and shown to be easily accessible with unsophisticated equipment. The applicability of the technique for quantitative analysis of samples with a range of relaxation rates is tested using various examples of practical interest. Highly reproducible results can be obtained much faster and without any special sample-dependent adjustments. 相似文献
43.
The using of the low calorie soft drink "Forest gift" based on plant raw and enriched with vitamin C and iodine by patients with diabetes mellitus has resulted in the improvement of carbohydrates metabolism, provision of iodine and vitamin C and oxidant status of organism. Obtained data has promised to recommend this product for using in patient's ration. 相似文献
44.
Ergonomists need easy-to-use, quantitative job evaluation methods to assess risk factors for upper extremity work-related musculoskeletal disorders in field-based epidemiology studies. One device that may provide an objective measure of exposure to arm acceleration is a wrist-worn accelerometer or activity monitor. A field trial was conducted to evaluate the performance of a single-axis accelerometer using an industrial population (n=158) known to have diverse upper limb motion characteristics. The second phase of the field trial involved an examination of the relationship between more traditional observation-based ergonomic exposure measures and the monitor output among a group of assembly-line production employees (n=48) performing work tasks with highly stereotypic upper limb motion patterns. As expected, the linear acceleration data obtained from the activity monitor showed statistically significant differences between three occupational groups known observationally to have different upper limb motion requirements. Among the assembly-line production employees who performed different short-cycle assembly work tasks, statistically significant differences were also observed. Several observation-based ergonomic exposure measures were found to explain differences in the acceleration measure among the production employees who performed different jobs: hand and arm motion speed, use of the hand as a hammer, and, negatively, resisting forearm rotation from the torque of a power tool. The activity monitors were found to be easy to use and non-intrusive, and to be able to distinguish arm acceleration among groups with diverse upper limb motion characteristics as well as between different assembly job tasks where arm monitors were performed repeatedly at a fixed rate. 相似文献
45.
本文以剪跨比和纵筋锚固长度为变参数,通过12根无腹筋矩形截面简支混凝土梁的24个试验及理论分析,探讨了纵筋锚固不足混凝土梁发生剪切破坏的工作及承载能力。 相似文献
46.
OBJECTIVE: To assess the extent and content of newspaper and magazine coverage of research on passive smoking. DESIGN: Content analysis of newspaper and magazine articles. SUBJECTS: Articles reporting on passive smoking research published in newspapers (n = 180) or magazines (n = 92) between January 1981 and December 1994. MAIN OUTCOME MEASURES: Numbers of articles, conclusions of articles, sources quoted, numbers and characteristics of research studies cited, presence of tobacco advertising. RESULTS: The number of newspaper and magazine articles reporting on passive smoking research increased from four in 1981 to 57 in 1992 and 32 in 1994. Sixty-two per cent (168/272) of articles concluded that the research on passive smoking is controversial. Tobacco industry representatives were quoted significantly more often in newspaper articles (52%, 94/180) than magazine articles (12%, 11/92) (p<0.0001). Of 121 different research studies cited in the lay press articles, only 15 were from tobacco-industry sponsored projects or publications. In magazines, acceptance of tobacco industry advertising was associated with the conclusion that research on passive smoking is controversial (p<0.0001). CONCLUSIONS: Although research on the harmful effects of passive smoking accumulated between 1981 and 1994, lay press coverage of the research maintained that the science was controversial. Few research studies were cited to support the industry's claim that passive smoking is not harmful to health. However, tobacco industry representatives who were critical of the research methods used to study the health effects of passive smoking were frequently quoted. 相似文献
47.
A novel Mott polarization analysis system is described. This system is much simpler than earlier designs and offers improved rejection of electrons inelastically scattered from the gold target foil. In addition the analyzer is capable of 'in-line' polarization measurements. 相似文献
48.
Fatty acid analysis of autoxidized cod-liver oil with a peroxide value of 192 showed significant degradation of only eicosapentaenoic,
docosapentaenoic, and docosahexaenoic acids of the linolenate family. Purified, mildly autoxidized cod-liver oil with a peroxide
value of 28, methyl eicosapentaenoate, and methyl docosahexaenoate produced carbonyl patterns in agreement with the accepted
mechanism for olefinic autoxidation. In all cases the major products were propanal andn-pent-2-enal as predicted, andn-hex-2-enal andn-hept-2-enal as reported in the literature for linolenate. In addition, the same cod-liver oil, which had been heated to 188C
in vacuum for 1 hr to decompose completely the hydroperoxides before carbonyl analysis, showed the presence ofn-hepta-2,4-dienal as predicted. 相似文献
49.
The age-related decline in intestinal lipid uptake is associated with a reduced abundance of fatty acid-binding protein 总被引:2,自引:0,他引:2
Aging is associated with changes in the absorptive capacity of the small intestine. We tested the hypotheses that (i) aging
is associated with a decline in lipid absorption, and that (ii) this decreased lipid absorption is due to a decline in the
abundance of mRNA and/or the enterocyte cytosolic intestinal FA-binding protein (I-FABP), the liver FA-binding protein (L-FABP),
and the ileal lipid-binding protein (ILBP). In vitro uptake studies were performed on Fischer 344 rats at ages 1, 9, and 24 mon. Northern blotting (L-FABP, ILBP) and immunohistochemistry
(I-FABP, ILBP) were performed. Aging was associated with decreased animal weights, but the surface area of the intestine was
not significantly altered with age. The rates of ileal uptake of 16∶0, 18∶0, 18∶1, and 18∶2 were reduced by greater than 50%
with aging when expressed on the basis of mucosal weight. This decline was not associated with reduced expression of mRNA
for L-FABP or ILBP but was associated with a 50% decrease in the abundance of I-FABP and a 40% decrease in the abundance of
ILBP. Thus, the decrease with aging in the ileal uptake of some FA when rates were expressed on the basis of mucosal weight
was associated with a reduced abundance of I-FABP and ILBP. 相似文献
50.
Barranco A Alonso-Salces RM Crespo I Berrueta LA Gallo B Vicente F Sarobe M 《Journal of food protection》2004,67(12):2786-2791
The levels of polycyclic aromatic hydrocarbons (PAHs) were determined by reversed-phase high-performance liquid chromatography with fluorescence detection in different fatty foods from a Spanish market. The average concentration of the sum of total PAHs in edible vegetable oils was below 25 ng/g, whereas the sum of heavy PAHs did not surpass 5 ng/g. Olive pomace oils obtained before the summer of 2001 were an exception because they were highly contaminated. The effects of different technological processes, such as bleaching, deodorization, and hydrogenation, on PAH concentration in edible oils have been studied. The PAH profiles, as well as the influence of cooking procedures, of other fatty foods (margarine, mayonnaise, and oils from canned fishes) have been examined. 相似文献