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排序方式: 共有451条查询结果,搜索用时 15 毫秒
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Dieke van Dinther Henrike Veninga Salvador Iborra Ellen G.F. Borg Leoni Hoogterp Katarzyna Olesek Marieke R. Beijer Sjoerd T.T. Schetters Hakan Kalay Juan J. Garcia-Vallejo Kees L. Franken Lamin B. Cham Karl S. Lang Yvette van Kooyk David Sancho Paul R. Crocker Joke M.M. den Haan 《Cell reports》2018,22(6):1484-1495
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S A Reese C E Crocker M E Carwile D C Jackson G R Ultsch 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2001,130(2):331-340
Map turtles from Wisconsin were submerged at 3 degrees C in normoxic and anoxic water to simulate extremes of potential respiratory microenvironments while hibernating under ice. In predive turtles, and in turtles submerged for up to 150 days, plasma PO2, PCO2) pH, [Cl-], [Na+], [K+], total Mg, total Ca, lactate, glucose, and osmolality were measured; hematocrit and body mass were determined, and plasma [HCO3-] was calculated. Turtles in anoxic water developed a severe metabolic acidosis, accumulating lactate from a predive value of 1.7 to 116 mmol/l at 50 days, associated with a fall in pH from 8.010 to 7.128. To buffer lactate increase, total calcium and magnesium rose from 3.5 and 2.0 to 25.7 and 7.6 mmol/l, respectively. Plasma [HCO3-] was titrated from 44.7 to 4.3 mmol/l in turtles in anoxic water. Turtles in normoxic water had only minor disturbances of their acid-base status and ionic statuses; there was a marked increase in hematocrit from 31.1 to 51.9%. This study and field studies suggest that map turtles have an obligatory requirement for a hibernaculum that provides well-oxygenated water (e.g. rivers and large lakes rather than small ponds and swamps) and that this requirement is a major factor in determining their microdistribution. 相似文献
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J L Brandhorst-Hubbard K L Flanders R W Mankin E A Guertal R L Crocker 《Journal of economic entomology》2001,94(6):1452-1458
Geostatistical analysis was used to map traditionally and acoustically sampled populations of soil invertebrates at two different times in a hayfield at Grove Hill, AL, and once in an Auburn, AL, hayfield. The distributions of nearly all the soil invertebrates and their sounds were nonrandom in all three mapping studies. The maps constructed by excavation and acoustic sampling methods were compared by correlating the estimated (kriged) soil invertebrate counts with the estimated (kriged) counts of sounds per minute (pulse rate). Acoustic and traditional estimates were positively correlated in the Auburn study. Kriged estimates for green June beetle grub counts overlapped significantly with kriged estimates of sound pulse rate (R2 = 0.47). Overlap with sound pulse rates increased slightly when other soil organisms were counted along with green June beetle grubs: estimates of sound pulse rates were significantly correlated with counts of all white grubs (R2 = 0.50), all white grubs with earthworms (R2 = 0.52), all white grubs with earthworms and earwigs (R2 = 0.59), and total invertebrates (R2 = 0.59). The correlation between acoustic and traditional estimates was not significant at Grove Hill in either year, possibly because of a lack of experience in signal analysis or because the soil invertebrates may not have generated enough sounds to be detected above the background noise levels. These results suggest that acoustic technology is a promising tool for detecting insect pests in soil, but that further study and additional analysis are needed to improve interpretation of acoustic data obtained in the field. 相似文献
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