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排序方式: 共有628条查询结果,搜索用时 15 毫秒
101.
Naomi Y.J. Brinkmans Nick Iedema Guy Plasqui Loek Wouters Wim H.M. Saris Luc J.C. van Loon 《Journal of sports sciences》2013,31(24):2759-2767
ABSTRACTSelecting effective dietary strategies for professional football players requires comprehensive information on their energy expenditure (EE) and dietary intake. This observational study aimed to assess EE and dietary intake over a 14-day period in a representative group (n = 41) of professional football players playing in the Dutch Premier League (Eredivisie). Daily EE, as assessed by doubly labelled water, was 13.8 ± 1.5 MJ/day, representing a physical activity level (PAL) of 1.75 ± 0.13. Weighted mean energy intake (EI), as assessed by three face-to-face 24-h recalls, was 11.1 ± 2.9 MJ/day, indicating 18 ± 15% underreporting of EI. Daily EI was higher on match days (13.1 ± 4.1 MJ) compared with training (11.1 ± 3.4 MJ; P < 0.01) and rest days (10.5 ± 3.1 MJ; P < 0.001). Daily carbohydrate intake was significantly higher during match days (5.1 ± 1.7 g/kg body mass (BM)) compared with training (3.9 ± 1.5 g/kg BM; P < 0.001) and rest days (3.7 ± 1.4 g/kg BM; P < 0.001). Weighted mean protein intake was 1.7 ± 0.5 g/kg BM. Daytime distribution of protein intake was skewed, with lowest intakes at breakfast and highest at dinner. In conclusion, daily EE and PAL of professional football players are modest. Daily carbohydrate intake should be increased to maximize performance and recovery. Daily protein intake seems more than adequate, but could be distributed more evenly throughout the day. 相似文献
102.
Karsten Koehler Hans Braun Markus De Marées Gerhard Fusch Christoph Fusch Joachim Mester 《Journal of sports sciences》2013,31(13):1435-1449
Abstract The assessment of nutrition and activity in athletes requires accurate and precise methods. The aim of this study was to validate a protocol for parallel assessment of diet and exercise against doubly labelled water, 24-h urea excretion, and respiratory gas exchange. The participants were 14 male triathletes under normal training conditions. Energy intake and doubly labelled water were weakly associated with each other (r = 0.69, standard error of estimate [SEE] = 304 kcal · day?1). Protein intake was strongly correlated with 24-h urea (r = 0.89) but showed considerable individual variation (SEE = 0.34 g · kg?1 · day?1). Total energy expenditure based on recorded activities was highly correlated with doubly labelled water (r = 0.95, SEE = 195 kcal · day?1) but was proportionally biased. During running and cycling, estimated exercise energy expenditure was highly correlated with gas exchange (running: r = 0.89, SEE = 1.6 kcal · min?1; cycling: r = 0.95, SEE = 1.4 kcal · min?1). High exercise energy expenditure was slightly underestimated during running. For nutrition data, variations appear too large for precise measurements in individual athletes, which is a common problem of dietary assessment methods. Despite the high correlations of total energy expenditure and exercise energy expenditure with reference methods, a correction for systematic errors is necessary for the valid estimation of energetic requirements in individual athletes. 相似文献
103.
104.
Morphological and biochemical responses of Oryza sativa L. (cultivar MR219) to ion beam irradiation 总被引:1,自引:0,他引:1
Anna Pick Kiong Ling Ying Chian Ung Sobri Hussein Abdul Rahim Harun Atsushi Tanaka Hase Yoshihiro 《Journal of Zhejiang University. Science. B》2013,14(12):1132-1143
Objective
Heavy ion beam, which has emerged as a new mutagen in the mutation breeding of crops and ornamental plants, is expected to result in the induction of novel mutations. This study investigates the morphological and biochemical responses of Oryza sativa toward different doses of carbon ion beam irradiation.Methods
In this study, the dry seeds of O. sativa were irradiated at 0, 20, 40, 60, 80, 100, and 120 Gy, followed by in-vitro germination under controlled conditions. Morphological and biochemical studies were conducted to investigate the morphological and physiological responses of O. sativa towards ion beam irradiation.Results
The study demonstrated that low doses (10 Gy) of ion beam have a stimulating effect on the height, root length, and fresh weight of the plantlets but not on the number of leaves. Meanwhile, doses higher than 10 Gy caused reductions in all the morphological parameters studied as compared to the control samples. The highest total soluble protein content [(2.11±0.47) mg/g FW] was observed in plantlets irradiated at 20 Gy. All irradiated plantlets were found to have 0.85% to 58.32% higher specific activity of peroxidase as compared to the control samples. The present study also revealed that low doses of ion beam (10 and 20 Gy) had negligible effect on the total chlorophyll content of O. sativa plantlets while 40 Gy had a stimulating effect on the chlorophyll content. Plantlets irradiated between 40 to 120 Gy were shown to be 0.38% to 9.98% higher in total soluble nitrogen content which, however, was not significantly different from the control samples.Conclusions
Carbon ion beam irradiation administered at low to moderate doses of 10 to 40 Gy may induce O. sativa mutants with superior characteristics. 相似文献105.
瓜子金皂苷己对鱼藤酮损伤PC-12细胞的保护作用及其对CREB的影响 总被引:1,自引:0,他引:1
目的:观察瓜子金皂苷己(polygalasaponin F,PS-F)对鱼藤酮损伤的PC-12细胞的保护作用及其对cAMP反应元件结合蛋白(cAMP response element binding protein,CREB)表达的影响。方法:以鱼藤酮损伤的PC-12细胞为模型,通过倒置显微镜观察细胞形态,caspase 3活性检测试剂盒测定caspase 3活性,荧光素酶报告基因技术检测CREB表达的变化。结果:PC-12细胞在4μmol·L-1鱼藤酮损伤后,细胞出现萎缩变圆,折光率降低,caspase 3活性显著升高,呈现凋亡的现象。不同浓度(0.1,1.0,10.0μmol·L-1)瓜子金皂苷己能够剂量依赖性的减轻对细胞形态的影响,降低caspase 3活性。荧光素酶报告基因标记显示,瓜子金皂苷己能够增加报告基因CREB的表达。结论:瓜子金皂苷己能够抑制鱼藤酮诱导的PC-12细胞凋亡,其机制可能与增加CREB的表达有关。 相似文献
106.
改良广播体操对男性大学生机体血脂代谢的影响 总被引:1,自引:0,他引:1
观察改良广播体操对30名男性大学生机体血脂代谢的影响。选择无遗传病史,无经常锻炼史的30名男性大学生为受试对象,每天进行两次30 min多组数的改良广播体操锻炼,锻炼强度以心率来控制,要求锻炼后心率在125次/min左右。观察受试者实验前、锻炼后第15 d、30 d、45 d晨安静空腹状态下,TG、TC、HDL-C、LDL-C和瘦素等指标变化。结果表明:45 d每天两次30 min、多组数的有氧广播体操锻炼可显著降低机体血浆TG和TC,预防TG堆积;HDL-C和HDL-C/LDL比值显著升高。说明有氧广播体操锻炼可使血浆脂蛋白的分布得到有效改善,从而预防和有效抵抗AS发生。 相似文献
107.
蛋白质结构预测在生物信息学研究中占有重要地位。对神经网络在蛋白质结构预测中的应用作了评述。首先,简要地介绍了人工神经网络,然后对近年来用神经网络算法解决蛋白质结构预测的研究作了回顾,并分析了算法的效果和特点。最后,展望了用神经网络算法解决蛋白质结构预测问题的前景。 相似文献
108.
作为二型糖尿病的潜在治疗药物,蛋白质酪氨酸磷酸酯酶1B(PTP1B)的抑制剂研究一直备受关注。而其中一种二齿类抑制剂由于其普遍较高的选择性和活性,又是抑制剂的研究重点和热点。本文采用分子动力学方法取样,MM/GBSA方法计算了1个二齿类PTP1B抑制剂与PTP1B及其2个同家族酶TCPTP和SHP-2的结合自由能,得到了与实验活性值相符的结果。同时基于MM/GBSA的能量分解计算表明,抑制剂与PTP1B第2位点附近的2个残基ARG24和ARG254有很强的相互作用,与其他2个酶第2位点的相互作用则有所减弱,尤其是SHP-2,几乎没有实质性相互作用。这应该是抑制剂产生选择性的关键。同时活性位点附近的残基PHE182也与抑制剂分子有很强的相互作用,相比TCPTP也有很大优势。希望这些信息在进一步提升PTP1B抑制剂的选择性和活性方面提供帮助。 相似文献
109.
Shrish Bhatnagar Farzana K. Beig Ashraf Malik 《Indian journal of clinical biochemistry : IJCB》2008,23(3):299-301
Adenosine deaminase and C-reactive protein in CSF were assessed in 72 cases of Tubercular meningitis, 24 cases of partially
treated pyogenic meningitis, 20 cases of Aseptic meningitis and 8 cases of febrile seizures. Mean Adenosine deaminase value
was 12.12±3.13 IU/L for Tubercular meningitis group. It was significantly higher (p<0.001) as compared to partially treated
pyogenic meningitis (5.39±2.70 IU/L) and aseptic meningitis (1.92±0.56 IU/L) groups. A combination of clinical criteria along
with biochemical test of Adenosine deaminase and C-reactive protein in CSF increased the sensitivity of diagnosing Tubercular
meningitis and differentiating it from other forms of meningitis at an early stage. 相似文献
110.
Ashavaid T. F. Altaf A. K. Nair K. G. 《Indian journal of clinical biochemistry : IJCB》2000,15(1):11-16
Modification of platelet proteins by free radicals and glycation has been studied in the present work, as anin vitro model. The results of the two parameters, SDS-PAGE and carbonylation study are quite corroborative. We observed that the
inducers like ferrous sulphate, ascorbate (mainly in supraphysiological concentration) and glucose attack the protein in a
dose dependent manner, of which ferrous sulphate is most potent. Proteins from aged and degenerative conditions like malignancy
and diabetes mellitus have suffered greater damage than normal adult and foetal proteins. The individual life expectancy in
terms of biological versus chronological age may also be worked out from the individual stress level. 相似文献