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Atsushi Maruyama Emi Tanahashi Takanobu Hirayama Ryuji Yonekura 《Ecology of Freshwater Fish》2017,26(4):636-642
Although stable isotope analysis is a powerful tool for determining diet, migration patterns and the structure of food webs in aquatic systems, the slow response of isotopic ratios in the widely used muscle tissue often hampers this approach, particularly in slow‐growing or adult fishes. We conducted a diet‐switch experiment to compare the changes in the stable carbon isotope ratio (δ13C values) in the epidermal mucus and muscle tissue of five‐year‐old catfish (Silurus asotus). The isotope ratios in noninvasively sampled mucus changed more rapidly than those in the muscle tissue. As isotopic change in mucus was relatively rapid, this technique can be used over a finer timescale than traditional isotopic analyses using the muscle tissue. The isotopic change half‐life in our experimental condition was 200 days, which would not be short enough for some research purposes. Examining mucus along with the muscle would enable food habits of slow‐growing fishes to be determined over different timescales. However, the rate of isotopic change in the mucus was negatively affected by the size of fish and was slower than the previously reported rates in juvenile steelhead. These findings suggest that mucus turnover rates need to be determined prior to the field data interpretation. 相似文献
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《Soil Science and Plant Nutrition》2013,59(3):408-416
Abstract The root parasitic plants Orobanche spp. (broomrapes) seriously affect agricultural production. A visualization and quantitative analytical method for the interception of nutrients was established using a positron-emitting tracer imaging system and 13NO? 3. By using this analytical method that involves volume normalization with 18F? images, the nitrogen nutrient interception ratio of the Orobanche spp. was calculated to be 73.6 ± 3.9% in a host–parasite system of red clover (Trifolium pratense L.). 相似文献
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Shingo Mitsui Sueo Aso Kiyoshi Tensho Kikuo Kumazawa 《Soil Science and Plant Nutrition》2013,59(1):17-18
The Foliar Uptake by Squash Plant The radioactive ash for experimental use, hereafter referred to as “Bikini ash”, was prepared by igniting the heavily contaminated substances on board No. 5 Fukuryu Maru at about 650°C, followed by sifting through a 100 mesh sieve. On ignition some parts of the fission products, particularly iodine, ruthenium and tellurium would have possibly been lost to the air. 相似文献
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Present Concepts on the Inflammatory Modulators with Special Reference to Cytokines* 总被引:2,自引:0,他引:2
Van Miert AS 《Veterinary research communications》2002,26(2):111-126
The pro- and anti-inflammatory cytokines create a network of interactions between cells that lead to both stimulatory and inhibitory responses that maintain an effective homeostatic regulation. The anti-inflammatory cytokines are a family of peptides that modulate the pro-inflammatory cytokine response. Cytokines act in concert with non-cytokine mediators, such as prostaglandin E2, glucocorticosteroids, lipocortins, and catecholamines. This review highlights new developments in our understanding of the pathophysiology of inflammation and gives an example of a more recent approach to the modulation of acute systemic inflammatory disorders: activation of 2-adrenergic receptors on macrophages. In this respect the potent 2-adrenergic agonist clenbuterol seems of therapeutic interest. 相似文献
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新蜜13号一代杂种的父本89-4和母本89-1均来自新疆当地厚皮甜瓜红心脆与欧美类型厚皮甜瓜的杂交后代。该品种单瓜重3kg以上,果实椭圆形,成熟果果皮金黄色,果面网纹细致,果肉浅桔红色,中心折光糖14度以上,肉质细、脆、香味浓郁,较耐贮运。成熟期比对照品种皇后提前5~10天,一般667m2产量可达2000~2500kg,对甜瓜枯萎病、蔓枯病、疫霉病有较强的抗性。 相似文献
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The absolute configuration of bisabolanoids isolated from Yaku-sugi wood were compared with those of dihydrocarvone and dihydrocarveol isomers based on their13C nuclear magnetic resonance data and optical rotations. 相似文献