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王维德 《吉林大学学报(工学版)》1990,(1)
本文论述了体育作为人类所特有的一种社会文化现象,系由三个层面组成,即外层的器物层,中层的制度层,内层则为观念层。为深化我国高校体育教学的改革工作,本文针对不同的文化结构层面试予理性探索,进而建立体育教学系统的圭臬框架。 相似文献
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Accumulating evidence strongly suggests that oxidative stress underlies aging processes. Research provides consistent evidence that calorie restriction (CR) reduces age-related oxidative stress and has anti-inflammatory properties. However, information is lacking on the molecular mechanism that would better define the interrelation of reactive oxygen species and nitrogen species and the pro-inflammatory states of the aging process. In this review, the biochemical and molecular bases of the inflammatory process in the aging process are analyzed to delineate the molecular inflammation hypothesis of aging. The key players involved in the proposed hypothesis are the age-related upregulation of NF-kappa B, IL-1 beta, IL-6, TNFalpha, cyclooxygenase-2, and inducible NO synthase, all of which are attenuated by CR. Furthermore, age-related NF kappa B activation is associated with phosphorylation by I kappa B kinase/NIK and MAPKs, while CR blocked these activation processes. The modulation of these factors provides molecular insights of the anti-inflammatory action of CR in relation to the aging process. Based on available finding and our recent supporting evidence, we prefer to use "molecular inflammation" to emphasize the importance of the molecular reaction mechanisms and their aberrance, predisposing to fully expressed chronic inflammatory phenomena. It was further proposed that CR's major force of the regulation of redox-sensitive inflammation may well be its life-prolonging action. 相似文献
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ABSTRACT: The effect of space flight and microgravity on the chemical senses is reviewed. Skylab-4 and Soyuz 30–31 studies revealed changes in taste thresholds while no effect was found in a Canadian investigation (41-G) and conflicting results were obtained on another Soyuz mission. Two simulated microgravity studies found no effect on taste or smell sensitivity; while 5 other studies found an effect. Microgravity induces physiological changes including an upward shift of body fluids toward the head, which may lead to an attenuation of the olfactory component in the flavor of foods. Chemosensory changes may also relate to space sickness, Shuttle atmosphere, stress, radiation, and psychological factors. 相似文献
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Feeding linseed to increase the n-3 PUFA of pork: fatty acid composition of muscle, adipose tissue, liver and sausages 总被引:3,自引:0,他引:3
Eighty pigs, male and female littermate pairs, were fed a control or a test diet from 25 to 95 kg live weight. The diets, as fed, contained 15.5 g/kg linoleic acid (18:2) and 1.9 g/kg α-linolenic acid (18:3) (control) or 10 g/kg linoleic acid and 4 g/kg α-linolenic acid (test). The test diet, with added linseed, was, therefore, high in the main n-3 polyunsaturated fatty acid (PUFA) 18:3 and low in the main n-6 PUFA 18:2. Making this relatively small change led to a 56% increase in the content of 18:3 in muscle and major increases in the contents of the beneficial longer chain PUFAs EPA (20:5n-3) (100% increase) and DHA (22:6n-3) (35% increase) which are synthesised from 18:3n-3. Levels of EPA and DHA in pigmeat adipose tissue were also increased by the test diet. In liver, the test diet resulted in an 18:3 level 4× higher than in muscle, with 10× more EPA and 20× more DHA. Sausages, analysed after 6 months frozen storage also had high n-3 PUFA levels, due to the contribution of these fatty acids from both muscle and adipose tissue. From a health perspective these results confirm the potential of pigmeat to supply valuable n-3 PUFA to the human diet. The test diet produced a PUFA:saturated FA ratio in muscle of 0.4, close to the minimum recommended value for the diet as a whole and an n-6:n-3 ratio of 5, a significant improvement on the current average for pigmeat (7). It is estimated that the test diet would provide 12 g of long chain n-3 PUFA to the human diet per annum at current pigmeat consumption levels in the UK, about a third of that from oily fish. 相似文献