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331.
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Dionyssios CH. Perdikis† Argyro A. Fantinou Dionyssios P. Lykouressis† 《Physiological Entomology》2003,28(4):331-339
Abstract. This study investigated the existence of rate isomorphy (the constant allocation of relative times to different stages of development under different abiotic conditions) in Macrolophus pygmaeus (Hemiptera: Miridae; a phytophagous and predatory insect). Replicated data were used from a range of temperatures regarding (i) the developmental period of each nymphal stage in relation to the total duration of nymph development, when feeding on three host plants either with different prey species or without prey, and (ii) its egg, total nymphal and preoviposition period, on two host plants, with different prey species. The proportion of time required for the development of each nymphal stage of M. pygmaeus is not different among the temperatures or the kind of food available. These proportions ranged among the different host plants, temperatures and prey presence/absence from 17.3–21.8% in the first, 14.5–18.8% in the second, 14.2–18.3% in the third, 16.5–21.0% in the fourth and from 25.4–30.6% in the fifth nymphal stage. Thus, temperature does not significantly affect the proportion of time spent in each nymphal stage and rate isomorphy exists in nymphal development. This phenomenon was also investigated using data from the literature, and it also occurs in several other Hemiptera species. Therefore, there appears to be a constant time allocation in the nymphal development of the higher taxonomic groups of insects. However, for M. pygmaeus, rate isomorphy does not hold when considering egg‐to‐egg development and the relative duration of times to egg hatch, total nymphal development and preoviposition period. The ecophysiological implications of this rate isomorphy phenomenon are discussed in relation to endocrinological mechanisms. Apart from its theoretical interest, the existence of rate isomorphy simplifies studies on the rate of development and the estimation of thermal constants of an insect, which are essential for the prediction of insect population dynamics. It is also proposed that the term ‘rate isomorphy’ does not strictly describe the phenomenon, and it is suggested that ‘constant rate allocation’ would be a more suitable term. 相似文献
333.
J. A. Dormandy E. Hoare J. Colley D. E. Arrowsmith T. L. Dormandy 《BMJ (Clinical research ed.)》1973,4(5892):576-581
Increased blood viscosity has been shown to be an important factor in reducing blood flow in a review and analysis of the history, clinical findings, and haemodynamic, rheological, radiological, and biochemical measurements in 126 patients with intermittent claudication. In some patients increased viscosity seemed to be the determining cause of claudication. A raised plasma fibrinogen was the most common single biochemical abnormality. The results of conventional serum lipid and lipoprotein estimations were abnormal in the series as a whole but did not correlate with clinical findings or flow measurements at individual patient level. There was, however, a significant correlation between some clinical findings and the susceptibility of the red cells to autoxidation. 相似文献
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336.
ATM-dependent telomere loss in aging human diploid fibroblasts and DNA damage lead to the post-translational activation of p53 protein involving poly(ADP-ribose) polymerase. 总被引:25,自引:1,他引:24 下载免费PDF全文
H Vaziri M D West R C Allsopp T S Davison Y S Wu C H Arrowsmith G G Poirier S Benchimol 《The EMBO journal》1997,16(19):6018-6033
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