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Lemurs are the most olfactory-oriented of primates, yet there is still only a basic level of understanding of what their scent marks communicate. We analyzed scent secretions from Milne-Edwards' sifakas (Propithecus edwardsi) collected in their natural habitat of Ranomafana National Park, Madagascar. We sought to test whether the scent mark could signal genetic relatedness in addition to species, sex, season, and individuality. We not only found correlations (r 2?=?0.38, P?=?0.017) between the total olfactory fingerprint and genetic relatedness but also between relatedness and specific components of the odor, despite the complex environmental signals from differences in diet and behavior in a natural setting. To the best of our knowledge, this is the first demonstration of an association between genetic relatedness and chemical communication in a wild primate population. Furthermore, we found a variety of compounds that were specific to each sex and each sampling period. This research shows that scent marks could act as a remote signal to avoid inbreeding, optimize mating opportunities, and potentially aid kin selection.  相似文献   
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Sonographic demonstration of normal tracheal diameter and breathing-related lung fluid flow at 30 weeks' gestation in a fetus with a giant neck mass confirmed patent airways, thus avoiding an EXIT procedure. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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本文提出怎样理解产学研相结合的问题,并从产学研不同层面进行分析,提出以市场为目标、以制度为保证实现产学研有效结合的思路。  相似文献   
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With increasing use of fetal ultrasound comes an increase in the detection of clinically silent ‘abnormalities’ which pose diagnostic and management dilemmas for perinatologists and paediatricians. Congenital thoracic malformations (CTMs) (excluding congenital diaphragmatic hernia) are one such example, where a few cases are symptomatic in early life and management options are clear, but the majority are clinically asymptomatic, giving rise to difficulties in defining postnatal management of the well child with a sonographic or radiological lesion. Here, we will outline the prenatal presentation and natural history of CTMs that are not congenital diaphragmatic herniae and briefly discuss the approach to postnatal management, which is covered in more detail in the review by Laje and Liechty in this issue. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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