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Pityrosporum pachydermatis was repeatedly isolated from portions of alopecic tissue from the throax and ears of a black bear cub (Ursus americanus). Yeastlike cells morphologically identical with those of P. pachydermatis were observed in stained tissue sections. This is the first reported association of this yeast with a member of the family Ursidae. 相似文献
994.
At 3-month intervals from birth to 27 months of age, 3 female armadillos were killed. The number and size of follicles greater than 202 micron were determined, plasma progesterone concentration was measured, and values were correlated with age. Blood samples were taken monthly by femoral vein puncture and plasma was analysed by radioimmunoassay for progesterone concentration. At necropsy, both ovaries were visually inspected for a corpus luteum, weighed and then processed for routine histology. The number of normal, antral follicles greater than 202 micron were counted. These follicles were arbitrarily categorized into 15 different size groups (every 77 micron). Total number of follicles greater than 202 micron varied from 15.5 +/- 1.3 at 15 months of age to 26.3 +/- 1.9 at 21 months. Follicles of a size (greater than 978 micron) most likely to ovulate were present only at greater than or equal to 9 months of age. Progesterone values remained below the adult concentration (5 ng/ml) until 15 months of age. A concentration of progesterone indicative of ovulation (approximately 10 ng/ml) occurred between 17 and 20 months of age. The findings of the present study demonstrate that the female armadillo is reproductively mature after 15 months of age. 相似文献
995.
Largemouth bass (Micropterus salmoides), when starved for 1 day, almost totally abstain from eating toad (Bufo americanus and Bufo woodhousei) tadpoles. However, there is a positive relationship between bass hunger levels and the acceptability of Bufo larvae as food items. With experience, there is a decrease in the number of toad tadpoles engulfed (taken into the mouth), and that actually consumed by the bass, while the number of larvae expelled (spat out) increases. Bass strongly prefer Hyla crucifer tadpoles to B. americanus larvae, and learn to distinguish between the two species. These results agree with the hypothesis that the schooling behaviour found in B. americanus tadpoles functions, at least in part, as a deterrent to predation. 相似文献
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Chris B Stone David C Bulir Jodi D Gilchrist Raman K Toor James B Mahony 《BMC microbiology》2010,10(1):18
Background
Flagellar secretion systems are utilized by a wide variety of bacteria to construct the flagellum, a conserved apparatus that allows for migration towards non-hostile, nutrient rich environments. Chlamydia pneumoniae is an obligate, intracellular pathogen whose genome contains at least three orthologs of flagellar proteins, namely FliI, FlhA and FliF, but the role of these proteins remains unknown. 相似文献999.
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