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Pedal progression of the slug Limax maximus was studied to obtain relations between wave velocity on the sole of the foot, wave frequency, the advance due to a single wave, and the velocity of vertically upward creeping. Each of the first three quantities is directly proportional to the simultaneous velocity of progression. Under comparable conditions, that is when work is done at a constant rate, the frequency of pedal waves is influenced by the temperature according to the equation of Arrhenius, with µ = 10,700 (Q
10 for 11° to 21° = 2.1). The velocity of a single wave must have very nearly the same "temperature characteristic," which is found also in another case of nerve net transmission (in Renilla). 相似文献
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Albrecht Grupe Gerhard Spiteller 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1982,230(2):335-344
The heterocyclic drug clomethiazole is metabolized by body passage partly to small aliphatic molecules. The occurrence of such unexpected metabolites is usually overlooked. An appropriate method for their detection is the comparison of urine profiles during drug intake and after withdrawal of the drug. 相似文献
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Detergent soluble extracts of differentiated regions of the Porphyra perforata J. Ag. thallus (holdfast, rhizoidal, vegetative and reproductive cells) were fractionated on sodium dodecyl sulfate polyacrylamide gels. Glycoproteins were identified by their lectin affinity. Extracts from all areas of the thallus contained glycoproteins, but the staining patterns were different for each region with each of the lectins tested: concanavalin A, Ulex europeaus agglutinin, Ricinus communis agglutinin, soybean agglutinin and peanut agglutinin. These data indicate that the morphologically distinct regions of the thallus also differ biochemically. Analysis of the lectin blots revealed the presence of tissue-specific glycoproteins in the five thallus areas. Such unique glycoproteins could be used as markers of differentiation in this species. 相似文献
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