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241.
To evaluate breastfed infants' responses to scented objects, we videotaped the facial and bodily reactions of sixty-three infants as they explored, in succession, three toys that were identical in appearance but different in their characteristic odor. Two of the toys were scented with odorants previously shown to be transmitted to human milk, one with ethanol and the other with vanilla, whereas the third toy was unscented. Each videotape was subjected to frame-by-frame analysis to measure a variety of behaviors that are considered either to be exploratory in nature in that they lead to perceptual information about the object or to reflect the infants' hedonic reaction. Analyses of these behaviors revealed that the infants looked more and vocalized less in the presence of the vanilla-scented toy and spent less time manipulating the ethanol-scented toy when compared with the unscented toy. Moreover, differential exposure to the odors of ethanol and vanilla, as indicated by differential consumption of alcohol by a parent or use of vanilla-scented product by the mother, was related to differential responses to these odors. These findings suggest that human infants are able to detect and retain information about the chemical features of their environment.   相似文献   
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C. Blanco    J. Aznar    J.A. Raga 《Journal of Zoology》1995,237(1):151-158
Fifteen cephalopod species from 28 stomach contents of striped dolphins, Stenella coeruleoalba (Meyen, 1833), stranded during an epizootic on the western Mediterranean coast in summer 1990, were analysed.
Albraliopsis pfefferi, Onychoteuthis banksii, Todarodes sagittatus and Brachioteuthis riisei are species showing higher relative importance indices. Composition and characteristics of cephalopod preys were discussed and compared to the scarce literature for this cetacean. The data showed a mixed diet of muscular and gelatinous body squids, mainly consisting of oceanic and pelagic or bathypelagic species.  相似文献   
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The stomachs and intestines of 23 dusky dolphins incidentally caught in a trawl fishery off Patagonia were surveyed for helminths. All the dolphins were parasitized, with a total of 3,936 helminth individuals. Only five species occurred, of which three were common (prevalence ± 10%): Anisakis simplex, Braunina cordiformis and Hadwenius sp. A. simplex was present in all the dolphins and showed the highest abundance and mean intensity (104.9 individuals/infected host). B. cordiformis was next most common (87%), and Hadwenius sp. third (52.2%). A. simplex was found mostly in the stomach (94.8%), B. cordiformis in the duodenal ampulla (51.4%), and Hadwenius sp. in the stomach (64.5%). The rare species Corynosoma australe (immature specimens) and Pholeter gastrophilus occurred in the stomach. A. simplex and B. cordiformis showed a clumped distribution along the intestine. Brillouin's diversity and evenness indices for the intestinal helminth community were 0.329 and 0.393, respectively. The diversity values and the number of parasite species were within the range for other small cetaceans.  相似文献   
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