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排序方式: 共有127条查询结果,搜索用时 15 毫秒
81.
Levine JA Lanningham-Foster LM McCrady SK Krizan AC Olson LR Kane PH Jensen MD Clark MM 《Science (New York, N.Y.)》2005,307(5709):584-586
Obesity occurs when energy intake exceeds energy expenditure. Humans expend energy through purposeful exercise and through changes in posture and movement that are associated with the routines of daily life [called nonexercise activity thermogenesis (NEAT)]. To examine NEAT's role in obesity, we recruited 10 lean and 10 mildly obese sedentary volunteers and measured their body postures and movements every half-second for 10 days. Obese individuals were seated, on average, 2 hours longer per day than lean individuals. Posture allocation did not change when the obese individuals lost weight or when lean individuals gained weight, suggesting that it is biologically determined. If obese individuals adopted the NEAT-enhanced behaviors of their lean counterparts, they might expend an additional 350 calories (kcal) per day. 相似文献
82.
Mannick JB Hausladen A Liu L Hess DT Zeng M Miao QX Kane LS Gow AJ Stamler JS 《Science (New York, N.Y.)》1999,284(5414):651-654
Only a few intracellular S-nitrosylated proteins have been identified, and it is unknown if protein S-nitrosylation/denitrosylation is a component of signal transduction cascades. Caspase-3 zymogens were found to be S-nitrosylated on their catalytic-site cysteine in unstimulated human cell lines and denitrosylated upon activation of the Fas apoptotic pathway. Decreased caspase-3 S-nitrosylation was associated with an increase in intracellular caspase activity. Fas therefore activates caspase-3 not only by inducing the cleavage of the caspase zymogen to its active subunits, but also by stimulating the denitrosylation of its active-site thiol. Protein S-nitrosylation/denitrosylation can thus serve as a regulatory process in signal transduction pathways. 相似文献
83.
84.
Blending of nylon filament with viscose can overcome the drawbacks of these yarns. Thermoplastic and thermoset filament yarns
can be blended in air-jet texturising method. The characteristics of nylon/viscose blended filament yarns are required to
be understood in order to convert them in to useful products. Therefore, nylon/viscose blended yarns in different proportions
were produced using nylon 6 and viscose filament yarns in air jet texturising machine. The textured yarns were also produced
in dry and pre-wet conditions to understand the effect of water on textured yarn characteristics. It was found that the loops
frequency, bulkiness of nylon/viscose blended textured yarns increase with increase in viscose proportion. The Loops stability,
tenacity and breaking elongation decrease with increase in viscose proportion. Pre-wet textured yarn show higher loops, bulkiness,
and good loop stability than their corresponding dry textured yarns. 相似文献
85.
A new generation of autoanalyzers was collaboratively studied for equivalency with instrumentation described in the AOAC method for crude protein in animal feeds. Twenty predigested samples were analyzed by 4 collaborators using standards that were provided. Means were comparable; the overall average difference was 0.07% protein. Analysis of variance indicated no evidence for an instrument difference. The method describing use of the Traacs 800 autoanalyzer as an alternative system has been adopted official first action. 相似文献
86.
Jeronimo Sean M. A. Lutz James A. R. Kane Van Larson Andrew J. Franklin Jerry F. 《Landscape Ecology》2020,35(4):859-878
Landscape Ecology - Post-fire tree mortality is a spatially structured process driven by interacting factors across multiple scales. However, empirical models of fire-caused tree mortality are... 相似文献
87.
88.
BC Li W Li H Chen YN Zhang ZT Zhang XY Wang B Gao TC Dou KH Wang 《Reproduction in domestic animals》2013,48(3):368-372
This study was conducted to explore the influencing factors of ova in vitro fertilization (IVF) and transfer of the fertilized ova into the oviduct of recipient hens. The efficiency of fertilization was compared using three aspects: (i) the different time of ova collection and transfer, (ii) egg‐laying period of recipient hen; and (iii) semen volume. The following results are observed: 72%, 40% and 0% of ova were found in ovarian sac in 30~40 min, 50~60 min and more than 90 min post‐oviposition, respectively; 20%, 18%, 14% and 5.8% of ova were fertilized with 0.1, 0.2, 0.5 and 1.0 ml semen, respectively; and 33% and 100% of healthy chickens were hatched from fertile ova with 0.1 and 0.5 ml of semen, respectively. All oocytes obtained from ovary and mid‐oviduct were unfertilized. Embryos were transferred into recipient hens 30 min ± 10 min post‐oviposition, and 70% of shelled eggs were produced. There were no eggs produced in the other transfer times. This demonstrated that live chicken can be obtained by IVF of ova collected shortly after oviposition. It was important that the ovum was transferred into the oviduct infundibulum of recipient hens immediately or shortly after oviposition. 相似文献
89.
Adeline Barnaud Yves Vigouroux Mamadou Tely Diallo Marie Piquet Mamadou Billo Barry Yacoubou Bakasso Leila Zekraoui Ronan Rivallan Ndjido A. Kane Claire Billot 《Genetic Resources and Crop Evolution》2017,64(7):1485-1490
In a context of the global major changes, it is mandatory to enlarge the range of crops supporting food security and pay great attention to neglected and underutilized species. However, basic knowledge of the biology of many neglected and underutilized species is still lacking to increase their yields. In this study, the mating system of white fonio [Digitaria exilis (Kippist.) Stapf], a West African minor and promising cereal, is assessed. Progenies arrays from both homozygous and heterozygous mothers were genotyped with microsatellites markers. The rate of genotyping errors in the experiments was assessed and a likelihood framework was used to determine the probability of different mating systems: outcrossing, self-fertilization and apomixis. The results suggested that white fonio has a highly selfing reproductive system with a possible outcrossing rate of 1.7%. Understanding the reproduction system of white fonio opens up opportunities for more effective breeding programs and a wider use of this cereal for food security improvement. 相似文献
90.
Growth and physiological responses of Sporobolus robustus kunth seedlings to salt stress 总被引:1,自引:0,他引:1
Fatoumata Fall Diégane Diouf Dioumacor Fall Niokhor Bakhoum Babacar Thioye Aboubacry Kane 《Arid Land Research and Management》2017,31(1):46-56
Seedlings of S. robustus were exposed to increasing NaCl concentrations (0, 50, 100, 150, 200, 250, and 300?mM) for 50, 100, and 150 days, in greenhouse conditions. Total dry weight and salt tolerance index decreased gradually with increasing NaCl concentrations. The optimum growth of S. robustus (4.12 to 5.25?g?·?plant?1) was obtained between 0 and 150?mM at 150 days after salt stress. Foliar chlorophyll a and total chlorophyll contents increased with NaCl concentration at 50 days after treatment. There was no significant effect of salinity on chlorophyll a, b and total chlorophyll contents at 100 and 150 days after treatment. Higher Na contents were found in the shoots as compared to the roots. The Na content increased, while K decreased with increasing NaCl concentrations, suggesting competitive inhibition between absorptions of Na and K as a consequence, the K/Na ratios in shoots and roots decreased with increasing salinity. The proline contents in S. robustus were more pronounced at 300?mM (2.02?µmol/g), 250?mM (2.64?µmol/g), and 200?mM NaCl concentrations (2.98?µmol/g) for 50, 100, and 150 days, respectively, as compared to the treatment without added NaCl. Overall, S. robustus could be considered as salt tolerant on the basis of their performance in biomass production, accumulation of Na, similar foliar chlorophyll a, chlorophyll b and total chlorophyll contents, and accumulation of proline with increasing salinity. The potential ability of S. robustus to accumulate significant amounts of Na makes this halophyte promising as a desalinization tool of salted soils. 相似文献