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David Shuker Nick Bateson Heidi Breitsprecher Rebecca O'Donovan Helen Taylor Chris Barnard Jerzy Behnke Sarah Collins Francis Gilbert 《Journal of Insect Behavior》2002,15(5):617-631
The function of male movements during copulation is unclear. These movements may be a result of the necessary mechanics of insemination, or they may also have further function, for instance, stimulating or courting a female during mating, perhaps influencing female mate choice. We present data from three experiments exploring the mating behavior and copulatory movements of the highly promiscuous beetle Psilothrix viridicoeruleus. Male mating success in the struggle over mating was not related to male or female size (measured by weight) but successful males were more vigorous in terms of copulatory movements. These males took longer to mount females but copulated longer and remained mounted longer. We discuss these results in terms of the mating system of Psilothrix and also in terms of observations of the timing of insemination during copulation. We suggest that copulatory movements in this species are best understood as copulatory courtship. 相似文献
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Summary Serum cholinesterase has been previously shown to complex with beta-lipoprotein in the plasma. Since serum cholinesterase exists as isoenzymes in plasma, the relationship between the activity of these isoenzymes (unbound to beta-lipoprotein) and lipoprotein titer was investigated. The results indicated that the total of C2, C3, and C4 isoenzyme activities were expressed within a narrow range and independent of low density lipoprotein titer. These findings may indicate that unbound plasma cholinesterase may undergo autoregulation independent of cholinesterase bound to beta-lipoprotein.Abbreviations WHHL rabbit
Watanabe Heritable Hyperlipidemic rabbit
- LDL
low-density lipoprotein
- VLDL
very low-density lipoprotein
- HDL
high-density lipoprotein
- C(1–4)
serum cholinesterase isoenzyme (1–4) 相似文献
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The cell biology of transforming growth factor beta 总被引:49,自引:0,他引:49
The TGF beta family of polypeptide growth factors regulates a remarkable diversity of cellular functions, many of which are not directly associated with cell growth. The present review has summarized many of the recent studies that have just begun to conceptually integrate this expanding array of TGF beta functions into the context of a three-dimensional, multicellular organ or tissue, be it normal or diseased. This fascinating research strongly implicates TGF beta as a key modulator of a wide variety of important physiologic and pathophysiologic processes. 相似文献