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401.
402.
This paper describes the effect of gel buffer pH on the resolution of bovine serum amylase (Amylase I) isozymes in starch gel and the consequences for the understanding of the genetics of this locus. The two main findings are: (1) the existence of a satellite isozyme E to isozyme C which at pH 7.3 has the same mobility as the B isozyme but which at pH 8.0 migrates slower than B, and (2) the finding of three alleles AmI A, AmI B and AmI C in British cattle populations previously reported as having only AmI B and AmI C . 相似文献
403.
M S NALINA SUNDARI 《The Annals of applied biology》1998,133(2):149-154
Studies on the effect of Catharanthus roseus alkaloids on the biology of Euproctis fraterna showed that at a dose of 10 ppm, only 19.25% fertile eggs were laid. The hatchability was totally suppressed at higher doses. There was a considerable reduction in total carbohydrate and protein content in treated larvae. The activity of digestive enzymes were also found to be inhibited. 相似文献
404.
In a genetic analysis of a polymorphic system, differences between the observed type of an individual and that expected from the parental types can arise either from an incorrect model or from pedigree errors. Such pedigree errors can cause severe difficulties in studies of the mode of inheritance of a novel polymorphic system. A method is proposed which overcomes the problem by including sire and dam error rates explicitly in the genetic model. The error rates are estimated by maximum likelihood, and likelihood ratio tests used to compare different models or estimates from different data sets. The proposals are applied to a study of the inheritance of the bovine serum AmI amylases. 相似文献
405.
Fraxinellone significantly reduced the relative growth rate, food consumption rate as well as the efficiency of conversion of ingested food into biomass of Heliothis virescens when incorporated into artificial diets at concentrations of 4.31 × 10−5 mol/L and above. After being fed with fraxinellone-treated diets for 24 h, the larval midguts of H. virescens possess significantly lower activities of α-amylase and non-specific proteases and higher activities of cytochrome P450s. In vitro , the compound did not inhibit the activities of α-amylase and non-specific proteases extracted from the larval midguts. Clear evidence of post-ingestive toxicity of fraxinellone to midgut cells was observed under an electron microscope. The modes of action of the compound against insects were discussed. 相似文献