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Pingping Su Kim Granholm Andrey Pranovich Leo Harju Bjarne Holmbom Ari Ivaska 《Wood Science and Technology》2013,47(5):1083-1097
The concentrations and protonation constants of the functional groups like carboxyl and phenolic hydroxyl groups in spruce bark were determined by a potentiometric acid–base titration method. The non-cellulosic carbohydrates in spruce bark were also characterized by acid methanolysis and GC, including determination of the uronic acid units, which are the key units involved in metal sorption. Sorption of metal ions to bark takes place by ion exchange, mainly by complexation to these functional groups. The sorption equilibrium time, studied by using a batch method, was approximately 5 min. The metal sorption capacity of spruce bark and the affinity order of metal ions were studied with four different metal ion mixtures using a column chromatographic method. Because a method of competition was used, concentration of metal ions adsorbed to bark depends on the metal ions present in the mixtures studied. In the sorption experiments with same metal ion mixtures, inner bark of spruce exhibited higher sorption capacity than outer bark. By combination of the results from several experiments, the following affinity order was obtained Fe3+ ? Pb2+ ? Cu2+ ? Cd2+ > Zn2+ > Ni2+ > Ba2+ > Ca2+ > Sr2+ > Mn2+ > Mg2+ ? K+ ~ Na+ ~ Li+. Bark has a great potential as an effective and inexpensive sorbent for removal of metal ions from, e.g., waste water. 相似文献
395.
In lambs with a very restricted intake of nutrients and an increase of the body mass of less than 60 g per day (group A) and in those with an increase of more than 220 g/day (group B), analyses of components of the blood and the plasma were performed at certain intervals. In the lambs of group A an anemia developed in the course of 77 days. The concentrations of alpha-amino-N, non-protein-N, urea, glucose and insulin as well as the activity of the alkaline phosphatase of the plasma of the lambs of group A were always lower than those of group B. The beta-hydroxybutyrate concentration of the lambs of group A on the 7th and 21st day of the experiment was higher than that of group B. The concentrations of inorganic phosphate and iron in the plasma of group A at most points during the study were lower than that in group B. 相似文献
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The effects of ethaboxam (LGC-30473), a novel thiazole carboxamide, on microtubule organization was investigated in Phytophthora infestans (Mont) de Bary (Oomycota) at the light microscope level using standard immunofluorescence and laser scanning confocal microscopy. Hyphal cells were exposed to various concentrations ranging from 0.01 to 1.0 microg ml(-1) of ethaboxam at incubation times of 30, 60 and 120 min. Microtubules were disrupted after exposure to ethaboxam for 30 min at 0.01 microg ml(-1). Similar experimental conditions were used to document the effects of ethaboxam on microtubule integrity in the model fungus Aspergillus nidulans (Eidam) Winter (Ascomycota) and in mammalian mouse 17 clone 1 cells. Under these conditions, there was no evidence to suggest that microtubules in A. nidulans and mouse culture cells were affected by the ethaboxam. These results indicate that ethaboxam is specific for the targeting of microtubule disruption in P. infestans. 相似文献
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Ike K Takeuchi K Uchida Y Imai S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(4):457-460
Hematological findings during the course of infection and the antibody response in Syrian hamsters infected with Babesia microti were examined. A macrocytic hypochromic anemia with an increase of the reticulocyte count was detected as a rise in the parasitized erythrocyte rate. White blood cell counts also remarkedly increased with the increases of both neutrophils and active-shaped monocytes, and thus they particularly play an important role in eliminating the parasite. In Western blotting with the sera from the hamsters infected with B. microti, a 38 kDa protozoan antigen reacted to the early-term sera, and additionally 28, 32, and 34 kDa antigens also reacted to the medium- and latter-term, and convalescent sera. These antigens were immunodominant and the antibodies against these antigens had also important roles for inhibition of this parasite. 相似文献
400.
Kato K Uchida K Murakami T Tateyama S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(10):1067-1070
A Japanese Black calf, 3 day-old male, showed severe ataxia, lateral recumbency, and opisthotonos at the birth. Histopathological examinations revealed severe status spongiosis throughout the central nervous system. Numerous vacuoles within the neuropile varying in size and shape were observed in both formalin-fixed paraffin and cryostat sections. In the lesions, a limited number of spheroids and macrophages were observed within the myelin sheaths with very mild astrogliosis. These vacuoles were negative for both periodic acid Schiff and Sudan black stains. The clinical and histopathological features were almost in conformity with those of bovine maple syrup urine disease (MSUD). Although we could not confirm completely the etiology, congenital hereditary neurological diseases including MSUD are considerable as the possible disease entry in the present case. 相似文献