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211.
Jay M. Fitzsimmons 《Oikos》2013,122(9):1350-1356
The use of species’ traits is increasing in ecological research. Many studies obtain trait data from a single source, implicitly assuming the accuracy of these data. I critically evaluate this assumption by measuring agreement among sources for trait data. I evaluate inter‐source agreement for 22 traits (anatomical, behavioural, life‐history and niche‐related) among five authoritative data sources (two field guides, two atlases and one online resource) for 263 Canadian butterfly species. This represents the first quantitative comparison of trait data among field guides or atlases. Traits varied considerably in their agreement among sources. Some traits such as wingspan and overwinter stage were fairly consistent among sources, whereas other traits such as habitat breadth were remarkably inconsistent among sources. These findings call into question the reliability of research that relies on a single source for trait data. I offer several recommendations for how trait researchers can account for inter‐source variation in trait data. 相似文献
212.
Stella Charleson Jillian F. Evans Robert J. Zamboni Yves Leblanc Brian J. Fitzsimmons Claire Leveill Philippe Dupuis Anthony W. Ford-Hutchinson 《Prostaglandins & other lipid mediators》1986,32(4)
Specific high-affinity binding sites for [3H]-leukotriene B4 have been identified on membrane preparations from rat and human leukocytes. The rat and human leukocyte membrane preparations show linearity of binding with increasing protein concentration, saturable binding and rapid dissociation of binding by excess unlabelled leukotriene B4. Dissociation constants of 0.5 to 2.5 nM and maximum binding of 5000 fmoles/mg protein were obtained for [3H] leukotriene B4 binding to these preparations. Displacement of [3H]-leukotriene B4 by leukotriene B4 was compared with displacement by leukotriene B3 and leukotriene B5 which differ from leukotriene B4 only by the absence of a double bond at carbon 14 or the presence of an additional double bond at carbon 17, respectively. Leukotriene B3 was shown to be equipotent to leukotriene B4 in ability to displace [3H]-leukotriene B4 from both rat and human leukocyte membranes while leukotriene B5 was 20–50 fold less potent. The relative potencies for the displacement of [3]-leukotriene B4 by leukotrienes B3, B4 and B5 on rat and human leukocyte membranes were shown to correlate well with their potencies for the induction of the aggregation of rat leukocytes and the chemokinesis of human leukocytes. 相似文献
213.
Robert C. Fitzsimmons Donna E. Mason 《In vitro cellular & developmental biology. Plant》1973,8(5):383-385
Summary Use of sterile membrane filters (Millipore) as a surface for embryo attachment and growth was attempted with success. Embryos
attached to the filters readily and showed development equal to or better than the controls which were maintained on a whole
egg-agar medium.
This investigation was supported by grant A 6059 from the National Research Council of Canada. 相似文献