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991.
Bobber is a genetic disorder in the domestic turkey that is usually expressed between two and four weeks of age. The condition is permanent and is characterized by ventrocaudad bending of the neck accompanied by a lateral pendulumlike motion of the head between the legs. Expressivity of the defect is variable and may be exhibited in some turkeys as a stargazing posture or a rapid clockwise twirling motion. When suspended by the legs in a head-down orientation, afflicted turkeys exhibit an inward turning of the neck and head toward the breast as opposed to an outward turning in normal turkeys. The disorder is inherited as a sex-linked recessive trait. The symbol bo is used for the gene. The defect can be corrected by exposure to intense light in the visible spectrum. 相似文献
992.
S. E. Shideler A. Savage A. M. Ortuno E. A. Moorman B. L. Lasley 《American journal of primatology》1994,32(2):95-108
A simple method for extracting and measuring ovarian steroids in feces is applied to the ovarian cycle, pregnancy, parturition, and period of lactational amenorrhea in Pithecia pithecia. Small amounts of wet, unmixed feces were combined with a modified phosphate buffer, shaken, centrifuged, and decanted, and the supernatant was directly measured for estrogen and progesterone metabolites by enzyme immunoassays. Urinary estrogen and progesterone metabolite measurements were compared to paired fecal measurements to determine the degree to which fecal hormone levels detected the same ovarian events as urinary measurements. The correlation coefficients for the relationship between urinary and fecal hormones for individual animals studied (n = 5) were found to be statistically significant in every case except one sexually immature animal. The application of the method presented here demonstrates that simple solubilization and non-radiometric measurement of ovarian steroids excreted in feces reliably reflect reproductive events in Pithecia pithecia. © 1994 Wiley-Liss, Inc. 相似文献
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Steven Brown Patrick E. Savage Albert Min-Shan Ko Mark Stoneking Ying-Chin Ko Jun-Hun Loo Jean A. Trejaut 《Proceedings. Biological sciences / The Royal Society》2014,281(1774)
We present, to our knowledge, the first quantitative evidence that music and genes may have coevolved by demonstrating significant correlations between traditional group-level folk songs and mitochondrial DNA variation among nine indigenous populations of Taiwan. These correlations were of comparable magnitude to those between language and genes for the same populations, although music and language were not significantly correlated with one another. An examination of population structure for genetics showed stronger parallels to music than to language. Overall, the results suggest that music might have a sufficient time-depth to retrace ancient population movements and, additionally, that it might be capturing different aspects of population history than language. Music may therefore have the potential to serve as a novel marker of human migrations to complement genes, language and other markers. 相似文献
997.
In the lizard isolated rectum, carbachol-, KCl- and quinine-induced contractions were reversibly inhibited by calcium withdrawal. Quinine-induced contractions were more sensitive to calcium lack than were those elicited by carbachol or KCl. Nifedipine inhibited contractile responses induced by all three agonists, but more readily blocked quinine- and carbachol- than KCl-induced contractile responses. It is suggested that extracellular calcium influx stimulated by carbachol, KCl and quinine occurs via different pathways, and that differentiation of calcium channels exists in lizard smooth muscle. 相似文献
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Adrenal and gonadal hormone levels were evaluated in representative species from Prosimii, Ceboidea, Cercopithecoidea, and Hominoidea to determine if endocrine activity was influenced by phylogenetic factors. Most small-bodied New World primates had extremely high levels of cortisol, progesterone, and testosterone when compared with Old World primates. In contrast to the high hormone levels and diversity found in Ceboidea, Old World primates showed a more similar pattern of hormone secretion. Thus, this survey supports earlier reports indicating that the callitricids and smaller cebid monkeys have a distinctive hormone profile. Although higher hormone levels tended to be associated with lower body weight, this effect was not evident in all taxa, and there were many notable exceptions. When species differ from their predicted hormone levels based on phylogenetic heritage and body weight (e.g., titi monkeys), we must look for other biological factors that influence endocrine activity. © 1992 Wiley-Liss, Inc. 相似文献
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