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R.A. Greenwald J.O. Cantor D.J. Prieur D.M. Young 《Biochimica et Biophysica Acta (BBA)/General Subjects》1975,381(2):435-437
Costal and auricular cartilage obtained from mutant rabbits exhibiting lysozyme deficiency has been found to be identical to similar tissue from control animals in a variety of biochemical parameters. These data seriously question the putative role of lysozyme as a structural component of cartilage. 相似文献
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An intersexual adult New Zealand longfinned eel Anguilla dieffenbachii , displaying testicular tissue within its ovaries, is described. Gonad samples were collected at 0, 21, 42 (by biopsy) and 54 days (autopsy) after the start of an experiment that aimed to induce ovarian maturation by repeated treatment with 5 mg kg−1 salmon pituitary homogenate (SPH). Very small patches of testicular tissue (almost always single seminiferous tubules), not visible macroscopically, were observed on all sampling dates. Treatment with SPH resulted in advanced stages of spermatogenesis in these seminiferous tubules, synchronous with the development of oocytes, which reached the migratory nucleus stage after 53 days. This finding is discussed in relation to current knowledge on sexual development in anguillid eels. 相似文献
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Fletcher J. Young Stephen H. Montgomery 《Proceedings. Biological sciences / The Royal Society》2020,287(1938)
Major evolutionary transitions can be triggered by behavioural novelty, and are often associated with ‘adaptive suites’, which involve shifts in multiple co-adapted traits subject to complex interactions. Heliconius butterflies represent one such example, actively feeding on pollen, a behaviour unique among butterflies. Pollen feeding permits a prolonged reproductive lifespan, and co-occurs with a constellation of behavioural, neuroanatomical, life history, morphological and physiological traits that are absent in closely related, non-pollen-feeding genera. As a highly tractable system, supported by considerable ecological and genomic data, Heliconius are an excellent model for investigating how behavioural innovation can trigger a cascade of adaptive shifts in multiple diverse, but interrelated, traits. Here, we synthesize current knowledge of pollen feeding in Heliconius, and explore potential interactions between associated, putatively adaptive, traits. Currently, no physiological, morphological or molecular innovation has been explicitly linked to the origin of pollen feeding, and several hypothesized links between different aspects of Heliconius biology remain poorly tested. However, resolving these uncertainties will contribute to our understanding of how behavioural innovations evolve and subsequently alter the evolutionary trajectories of diverse traits impacting resource acquisition, life history, senescence and cognition. 相似文献
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Young June Lee 《Journal of Asia》2013,16(4):369-372
A new cicada genus and species, Minilomia triquetra, gen. and sp. nov., is described from Borneo. The new genus Minilomia is closely allied to Platylomia Stål and is placed in the subtribe Dundubiina of the tribe Cicadini. Another new cicada species, Pomponia brevicaudata, sp. nov. (subtribe Psithyristriina), is described from Java and Sumatra. The new species belongs to the Pomponia linearis species group and the P. linearis species complex but is distinguished from its congeners by the unusually short male abdomen. 相似文献
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Comment on: Xu R, et al. Cell Cycle 2010; 9:4315-4322. 相似文献
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