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191.
I. Chanarin M. Hutchinson Anne McLean Margaret Moule 《BMJ (Clinical research ed.)》1966,1(5484):396-399
192.
Summary The effect of Triton X-100 on the activities of acid phosphatases from wheat germ, potato and human prostate was tested using -glycerophosphate, p-nitro-phenyl phosphate and naphthol AS BI phosphate as substrates. There was little effect on -glycerophosphatase activity at the concentrations of Triton X-100 tested. However at low concen trations of the detergent there was a stimulation of the activities of p-nitrophenyl phosphatase and naphthol phosphatase which were inhibited with the higher concentrations. Triton X-100 was found to enhance colour production between naphthol AS BI and fast red violet LB.Further evidence is presented confirming the presence of more than one acid phosphatase from each of the sources employed. 相似文献
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Verticillium lecanii (Fungi: Deuteromycete) blastospores were applied to a chrysanthemum crop by an ULV electrostatically charged rotary atomiser
(APE-80). The deposition of spores and subsequent control ofAphis gossypii were compared to high volume hydraulic application. A full rate treatment (2×1013 blastospores per ha.) was applied by the APE-80 at week 1 and reduced spore rates of 1/6th and 1/12th applied by both the APE-80 and the hydraulic sprayer once and twice a week respectively for weeks 1 to 6. Untreated plots
served as controls.
Initial deposits of spores were higher with the electrostatic sprayer and better distributed with respect to the position
of the target aphids. Significantly lower aphid populations were recorded on the electrostatically treated plots in week 4.
The single full rate treatment had significantly fewer aphids than the untreated plots from week 3 and all treatments had
significantly fewer aphids than the untreated plots from week 5 onwards. The proportion of the aphid population killed byV. lecanii was higher on the electrostatically treated plots until week 6.
相似文献
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198.
Summary The ages of 252 mature female krill, collected from Prydz Bay in January 1985, were determined using length frequency analysis and the fluorescent age pigment (FAP) technique. Results of both methods suggest 6 years classes for adult krill. Correspondence between the ages determined by the two techniques is generally within one year. The animals were also analyzed by a computerized image analysis system, which recorded a large suite of size and shape parameters. The accuracy of discriminant functions constructed to relate the image analysis parameters to age approached 90% for the ages defined by length frequency, and 52% for physiological age. 相似文献
199.
Anne Marpeau Jocelyne Walter Jacqueline Launay Jacqueline Charon Philippe Baradat Michel Gleizes 《Trees - Structure and Function》1989,3(4):220-226
Summary The effect of wounds on the volatile terpene composition of the living bark of Pinus pinaster Ait. (maritime pine) twigs was investigated with respect to the processes of mono- and sesquiterpene hydrocarbon biosynthesis. The large increase in the amounts of - and -pinene is a characteristic feature after a mechanical injury, whereas the quantities of the other terpenes are only slightly increased. This is due to the reactivation of the resin duct secretory cells of primary origin located in cortical tissues. The effect of wounding is observed over a long period and the terpene profiles are very different at the end of the experiments as compared with the initial profiles of the same tissues. The traumatic essential oil (obtained after mechanical traumatism) resembles an oleoresin extracted from tissues of secondary origin. Statistical analysis underlines the effects of the between-tree variations and of the dates of application of the wound. 相似文献
200.
François M. Catzeflis Eviatar Nevo Jon E. Ahlquist Charles G. Sibley 《Journal of molecular evolution》1989,29(3):223-232
Summary DNA-DNA hybridization was used to measure the average genomic divergence among the four chromosomal species of the Eurasian mole rats belonging to theSpalax ehrenbergi complex (Rodentia: Spalacidae). The percent nucleotide substitutions in the single-copy nuclear DNA among the species ranged from 0 to 5%, suggesting that speciation has occurred with minor genomic changes in these animals. The youngest chromosomal species appear to differ by 0.2–0.6% base pair mismatch, which is only between one and three base differences in a 500-bp fragment. The interspecific values of percent nucleotide differences permit the recognition of two well-separated speciation events in theS. ehrenbergi complex, the older (of Lower Pleistocene age) having isolated the chromosomal species 2n=54 before the divergence of the three other species.DNA-DNA hybridization was also used to compare the Spalacinae (Eurasian mole rats), Murinae (Old World rats and mice), and Arvicolinae (voles and lemmings). These data enabled us to estimate the time of divergence of the spalacids at ca. 19 million years ago. The dates of divergence among the other rodent lineages, as predicted by DNA hybridization results, agree well with paleontological data. These dates of divergence are obtained by the relation between geological time and single-copy nuclear DNA change, a relation that was calibrated by Catzeflis et al. (1987) through the use of fossil Arvicolinae and Murinae data. 相似文献