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111.
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
112.
Ciliary neurotrophic factor (CNTF) has pleiotropic actions on many neuronal populations as well as on glia. Signal transduction
by CNTF requires that it bind first to CNTF-R, permitting the recruitment of gp130 and LIF-R, forming a tripartite receptor
complex. Cells that only express gp130 and LIF-R, but not CNTF-R are refractory to stimulation by CNTF. On many target cells
CNTF only acts in the presence of its specific agonistic soluble receptors. We engineered a soluble fusion protein by linking
the COOH-terminus of sCNTF-R to the NH2-terminus of CNTF. Recombinant CNTF/sCNTF-R fusion protein (Hyper-CNTF) was successfully expressed in COS-7 cells. The apparent
molecular mass of the Hyper-CNTF protein was estimated from western blots to be 75 kDa. Proliferation assays of transfected
BAF/3 cells in response to CNTF and Hyper-CNTF were used to verify the activity of the cytokines. The proliferative results
confirmed that CNTF required homodimerization of the gp130, CNTF-R and LIF-R receptor subunit whereas Hyper-CNTF required
heterodimerization of the gp130 and LIF-R receptor subunit. We concluded that the fusion protein Hyper-CNTF had superagonistic
activity on target cells expressing gp130 and LIF-R, but lacking membrane-bound CNTF-R.
Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholar, Zhejiang Province, China
and SFB415, TP B5, Germany. 相似文献
113.
114.
[目的]应用生物信息学分析人类新基因乙型肝炎病毒(HBV)DNA聚合酶(Polym erase)反式调节蛋白(HBVDNAPTP1)结合蛋白(HBVDNAPTP1BP).[方法]利用生物信息学技术分析HBVDNAPTP1BP基因的染色体定位与组织表达,以及编码蛋白的化学物理性质与结构特征.[结果]HBVDNAPTP1BP基因染色体定位于1号染色体短臂3区5带1亚带,可在组织中低表达,但在多个组织中无表达.HBVD-NAPTP1BP的相对分子量为11 905.6,理论pI为7.72,不同条件下的消光系数为14 230 M-1cm-1或13 980M-1cm-1(280 nm),在体外哺乳动物网状细胞中的半寿期为30 h,并且无卷曲螺旋区域,但具有3个较强的疏水区域.HBVDNAPTP1BP无特殊二级结构,仅有1个蛋白激酶C磷酸化位点,不具有跨膜螺旋结构,无信号肽序列,定位于细胞核中.[结论]应用生物信息学对HBVDNAPTP1BP进行了分析,为进一步研究其生物学功能及其在乙型肝炎、肝细胞癌中的作用机制提供了依据和线索. 相似文献
115.
目的:探讨ER、erbB-2和P53在胃癌表达及相关性。方法:取胃癌手术标本119例,SP免疫组织化学染色。结果:ER、erbB-2和P53在胃癌表达率分别为63.87%,75.51%和73.11%;三者同时阳性者31.93%;ER与P53同时阳性者37.82%;ER与erbB-2同时阳性者33.61%;ER在高分化组阳性率高于低分化组(P<0.05);而erbB-2和P53在低分化组阳性率高于高分化组。70岁以上组P53、ER和erbB-2表达率均较高。结论:ER、P53和erbB-2在胃癌中表达率与癌瘤分化程度相关。P53和erbB-2有相关性,而且它们是胃癌预后不良的指标。 相似文献
116.
Chai?Ming-liang?Email author Wang?Bing-liang Kim?Jae-yeoul Lee?Jong-min Kim?Doo-hwan 《浙江大学学报(A卷英文版)》2003,4(3):346-351
Embryogenic calli were induced from the seeds of creeping bentgrass (Agrostis palustris Huds.) cv. Regent and colonial bentgrass (Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4–7 days and then co-cultivated withAgrobacterium tumefaciens, LBA4404. which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding
region and matrix attachment region (MAR). After 3 days of co-cultivation, the calli were washed thoroughly and transferred
to MS medium containing 2 mg/L of 2, 4-D, 12–15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2–3 months of
selection, the actively growing calli of ‘Regent’ and ‘Tiger’ were transferred to MS medium with 12–15 mg/L PPT and 250 mg/L
cefotazime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control
died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide
Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP
expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants
and its absence in a randomly selected control plant. 相似文献
117.
目的:观察诺和锐30特充对2型糖尿病患者血浆C-反应蛋白的影响。方法:选择80例2型糖尿病病人,随机分为诺和锐治疗组及诺和灵30R治疗组,诺和锐为餐前即刻皮下注射,诺和灵30R为餐前30min皮下注射,观察两组病人治疗前后餐前、餐后血糖及血浆C-反应蛋白(C-reactive protein,CRP)情况。结果:诺和锐治疗组餐后血糖水平低于诺和灵30R组(P〈0.01),诺和锐治疗组治疗后C反应蛋白水平明显低于诺和灵30R治疗组(P〈0.01)。结论:对于2型糖尿病患者,诺和锐疗效优于诺和灵30R,而且可以显著降低血浆CRP的水平。 相似文献
118.
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119.
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
120.
Feng-wei Song Bin-bin Chen Zhao-hui Sun Li-ping Wu Su-juan Zhao Qi Miao Xia-jing Tang 《Journal of Zhejiang University. Science. B》2013,14(6):479-486