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81.
82.
In this study, we re-describe the advertisement and territorial calls of Boana pardalis, carry out an acoustic comparison between the studied species and the other congeners of the B. faber group, and report for the first time the tympanic amplexus for the studied species. The advertisement call of B. pardalis can be used to supplement its diagnosis in the B. faber group based on temporal call traits, e.g. emission rate and emission pattern, as well as the call envelope.  相似文献   
83.
This study analyzes a giant anteater’s (Myrmecophaga tridactyla) movement patterns and space use in São Paulo, Brazil. It is the first study to track a giant anteater with Iridium-GPS. The anteater traveled an average distance of 1326 m day–1 with an average speed of 1.04 m min–1. Home range by Kernel was 2.46 km2 while the core area was 0.75 km2, and estimates by Brownian bridge and minimum convex polygon were also provided. The anteater used shrub savanna, open savanna, and water habitats more than expected. Monitoring ended just after 10 days when the female giant anteater’s GPS was found on an illegal trail.  相似文献   
84.
85.
The rostrum of most ziphiids (beaked whales) displays bizarre swollen regions, accompanied with extreme hypermineralisation and an alteration of the collagenous mesh of the bone. The functional significance of this specialization remains obscure. With the voluminous and dense hemispheric excrescence protruding from the premaxillae, the recently described fossil ziphiid Globicetus hiberus is the most spectacular case. This study describes the histological structure and interprets the growth pattern of this unique feature. Histologically, the prominence in Globicetus is made up of an atypical fibro‐lamellar complex displaying an irregular laminar organization and extreme compactness (osteosclerosis). Its development is suggested to have resulted from a protraction of periosteal accretion over the premaxillae, long after the end of somatic growth. Complex shifts in the geometry of this tissue are likely to have occurred during its accretion and no indication of Haversian remodeling could be found. X‐ray diffraction and Raman spectroscopy indicate that the bone matrix in the premaxillary prominence of Globicetus closely resembles that of the rostrum of the extant beaked whale Mesoplodon densirostris: apatite crystals are of common size and strongly oriented, but the collagenous meshwork within bone matrix seems to be extremely sparse. These morphological and structural data are discussed in the light of functional interpretations proposed for the highly unusual and diverse ziphiid rostrum. J. Morphol. 277:1292–1308, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
86.
87.
We report observational data on behavioral laterality in 10 captive bonobos (Pan paniscus)at the San Diego Zoo. The unimanual measures include carrying, leading limb in locomotion, self-touching, face-touching, reaching, and gestures. We also recorded bimanual feeding in these subjects. A significant population level left-hand bias exists for carrying. Right-hand biases occur for leading limb in locomotion and gestures. During bimanual feeding, the bonobos hold food items with the left hand while feeding with the right hand. Overall, bonobos exhibit behavioral asymmetries that are similar to previous findings in other pongid ape species. The asymmetries in gestures and bimanual feeding represent novel findings with theoretical implications for the origins of tool use and language.  相似文献   
88.
Lysophosphatidic acid (3-sn-lysophosphatidic acid; LPA) can activate cells similar to hormones and growth factors. We have considered the question whether metabolic conversion of LPA taken up by the cell could be of any importance in this activation. Addition of [14C-glycerol]LPA to quiescent Rat-1 fibroblasts resulted in rapid formation of [14C]monoacylglycerol (MG), closely followed by accumulation of [14C]triacylglycerol. Only very little [14C]diacylglycerol and [14C]phosphatidic acid was formed (approx. 100-fold less than MG). MG, when added exogenously to cells, lacks detectable biological activity. The results suggest that LPA itself, rather than one of its metabolites is the biologically active principle.  相似文献   
89.
In this paper we report our studies on the effects of menadione in cultured fibroblasts treated with rotenone to block complex I. A normalization of the lactate to pyruvate ratio after incubation with glucose, an increased production of 14CO2 from [6-14C]glucose and an increased intra-cellular concentration of ATP was observed in the presence of micromolar concentrations of menadione. These results not only demonstrate the potential value of menadione in complex I deficient patients but also suggest that this system can be used advantageously for the in vitro assessment of therapeutic agents for disorders of the mitochondrial respiratory chain.  相似文献   
90.
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