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1.
齐斌文 《绿色科技》2021,(6):202-204,218
采用文献资料法对食用菌多糖抗运动疲劳的研究进展情况进行了研究。结果表明:食用菌多糖提取方法不同而食用菌多糖的提取率也不相同,超声波法+复合酶法及微波法提取食用菌多糖提取率较高,2种方法科学合理的结合提取食用菌多糖以及不同产地、品种和不同部位提取率是未来学者们需要研究的领域;目前,只是对极少部分食用菌多糖抗运动疲劳进行了研究,研究对象(动物)、模型、指标、评价单一而没有确定最佳剂量的时间而没确定的量。为此,提出了未来应加强和重视食用菌多糖抗疲劳运动多食用菌、多对象(尤其是人)、多模型、多指标、多评价、最佳剂量的研究以及量-效、构-效关系的研究建议。  相似文献   
2.
对50例冠心病和50例随机做平板运动试验(TET)者作频域心电图(FCG)对比分析探讨FCG对冠心病的诊断价值。结果表明:单纯根据FCG异常诊断冠心病有较高假阳性(65.22%)。如将FCG的阳性指标作综合判断,虽然敏感性降低(88.00%降至70.00%)。假阳性都明显降低(65.22%降至26.00%)。认为TET的特异性较FCG高。若两者均为阴性,则冠心病可能性很小。  相似文献   
3.
Fifty-eight healthy horses were studied during five sporting events of various intensities and durations, namely show-jumping (n=6), cross-country in a three-day event (n=30), trotting races (n=7), galloping reces (n=7) and endurance rides (n=8). Venous blood samples were collected at rest and immediately after exercise and analysed for plasma cortisol (CORT) and lactate (LA) levels. The experimental procedure was the same throughout the investigation so as to permit a reliable comparison between the five types of exercise. The type of event significantly affected both the resting (p0.05) and the postexercise (p0.01) plasma CORT. The degree of exercise-induced hypercortisolaemia was related to both the intensity and the duration of exercise for all five sporting events, but the endurance ride induced the most and show-jumping the least serious post-exercise CORT changes. LA production was much more closely related to the intensity of the exercise than was CORT. It is concluded that simultaneous measurements of plasma CORT and LA levels may be useful to discriminate between different types of exercise, adjust training programmes, and improve our comprehension of the physiology of sport horses at exercise.Abbreviations CORT cortisol - E/R exercise to rest ratio - EDTA ethylenediaminetetraacetic acid - HR heart rate - LA lactate  相似文献   
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通过分析松茸多糖对有氧运动所产生的一系列良好效果,进行松茸多糖对运动员疲劳恢复的相关研究,松茸多糖主要涉及到运动员运动过程当中,其机体所产生的血清尿素(BU)含量、血清丙二醛(MDA)含量、血清肌酸激酶(CK)、血清超氧化物歧化酶(SOD)以及谷胱甘肽过氧化物酶(GSH-PX)活性的变化。相关研究结果表明,松茸多糖能够对此起到良好的修复作用,有效抑制运动过后所产生的骨骼肌损伤,增强运动员机体抗氧化能力,从而达到恢复疲劳的作用。  相似文献   
6.
OBJECTIVE: To determine whether percentages of neutrophils in tracheal aspirate (TA) samples collected from racehorses are increased after exercise and whether interpretation of results from TA samples taken before and after exercise agree. DESIGN: Case series of 40 young Thoroughbred and Standardbred racehorses in race training presented for evaluation of poor performance. PROCEDURE: TA samples were collected endoscopically from racehorses presented for poor performance 24 h before and 1 to 2 h after high speed treadmill exercise testing. Aliquots of the retrieved fluid were cytocentrifuged and smears were stained with Diff-Quik. Mean neutrophil counts were expressed as percentages of the total number of inflammatory cells counted and subsequently were categorised as either above or below an accepted cut-off of 20%. Comparisons between percentages of neutrophils before and after exercise were made. RESULTS: Percentage of neutrophils from TA samples obtained from racehorses after exercise was significantly higher than neutrophil percentages from TA samples collected from the same horse before exercise. In horses with TA specimens that were categorised as having < or = 20% neutrophils before treadmill exercise, the percentage of neutrophils in their TA specimens after exercise was, on average, significantly higher and was greater than the cut-off value of 20%. CONCLUSION: Recent strenuous exercise may change the proportion of neutrophils in lower airways of racehorses and practitioners should be aware of this when collecting and interpreting the results from TA samples. The most practical time for collection of a TA sample to obtain the most diagnostically useful information might be after a suitable washout period of at least 1 to 2 h post-exercise.  相似文献   
7.
Navicular bones from the four limbs of 95 horses, classified in 9 categories, were studied. The effects of age on navicular bone morphometry and histomorphometry were estimated, after adjustment of the data to even out the effects of front and rear limbs, morphometrical type, sex, weight, and size.All the external measurements of the navicular bone decreased significantly with increasing age. From the histomorphometrical data, cortical bone volume decreased with age in most horses, whereas cancellous bone volume and, in particular, the marrow spaces increased. The increase in the cancellous bone volume could have resulted from tunnelling of the internal part of the cortex, which converted it progressively into a porous trabecular-like structure. Trabecular bone volume also decreased with age and the trabecular lattice changed dramatically to become disconnected in aged horses. These observations corresponded closely to those reported for ageing of the skeletal system in humans.However, in sporting horses, the navicular cortical bone volume increased with age and the cancellous bone volume decreased. Exercise appeared to have decreased bone resorption and increased bone formation at the endocortical junction. The cancellous bone architecture was also improved, in that the trabecular lattice and trabecular bone volume remained unchanged in aged sporting horses. Our findings confirmed that exercise may be good practice to prevent age-related bone loss.  相似文献   
8.
The effect of training on the potential for work in draught cattle was assessed by measuring the Na+,K+-ATPase in the muscle cell membrane and the elevation in the concentration of K+ in plasma during exercise. Biopsies of the semitendinosus muscle and venous blood samples were taken from the cattle used for draught work in Mozambique. No differences were found in the plasma ion or Na+,K+-ATPase concentrations in samples taken from Nguni, Africander and Angoni breeds. There were no significant differences in plasma ions (Na+, K+ and Cl) or muscle Na+,K+-ATPase concentrations between the Angoni males and females, although the males showed an increase in Na+,K+-ATPase with age, while the females showed a decrease. The increase in males might be attributed to their higher level of activity in the herds than that of females. After a training period of 15 days, a significant increase in Na+,K+-ATPase concentration in semitendinosus muscle was found in Angoni cattle. In females, this was significant after 8 days of training (about 30%); in males after 15 days of training (about 16%). On day 15, there was a reduction in the elevation of plasma K+ during the 2 h of draught work, indicating an increased capacity of the Na+,K+ pumps to maintain the extracellular K+ concentration in working muscles and a possible delay in the moment of fatigue.  相似文献   
9.
The purpose of the present paper was to investigate the effect of regular walking exercise on glucose tolerance and insulin response to i.v. glucose infusion in growing beef steers. Four crossbred beef steers walked on a treadmill during a 6 week exercise period (1.2 km/h, 1 h/day and 5 days/week). The changes in plasma glucose and insulin levels following glucose infusion were analyzed immediately prior to (bodyweight: 260.4 ± 24.2 kg) and after (295.7 ± 30.1 kg) the exercise period. The basal levels of plasma glucose (86.4 vs. 82.0 mg/dL, P = 0.040) and insulin (24.5 vs. 14.3 μU/mL, P = 0.016) were significantly lower after the exercise period. Further, the increase in the levels of plasma glucose (420.4 vs. 280.8 mg/dL, P < 0.001) and insulin (94.5 vs. 73.1 μU/mL, P = 0.028) following the glucose infusion decreased after the exercise period. The area under the curve of plasma glucose (108.8 vs. 62.9 mg/dL per min, P < 0.001) and insulin (53.6 vs. 29.7 μU/mL per min, P = 0.018) indicated more rapid clearance of exogenous glucose and less insulin secretion for glucose clearance after the exercise period. These results suggest that regular exercise improves glucose tolerance, with lower insulin response to glucose infusion in growing steers, as observed in rodents and humans.  相似文献   
10.
In order to investigate the effect of age, sex and month on the response of plasma aspartate aminotransferase(AST) and creatine kinase (CK) to exercise, blood samples were collected once a month between March and September from a group of 40 2- and 3-year-old (2yo and 3yo) thoroughbred racehorses (kept under the same managemental regimen) at rest before exercise (PRE) and at 2 (2H) and 24h (24H) post-exercise. The absolute change in activities between the 2H and PRE samples (2HΔ) and the 24H and PRE samples (24HΔ) was also calculated. Age had a significant effect on all measured and calculated parameters for colts (C), apart from 24HΔ CK but showed no effect in the fillies (F). Sex only had a significant effect in the 3yo in the 2HΔ CK. In the 2yo, significant effects of sex were found for both CK and AST in the PRE, 2H and 24H samples. The effect of month varied according to the classification group with only the 2yoC not showing any significant effect on any parameter. Fillies were, in general, more likely than colts to show greater than a twofold increase in CK activity at 2H post-exercise and the number of animals showing such an increase decreased as the season progressed. Very little change in AST activities occurred with exercise.  相似文献   
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