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41.
This study aims to investigate how intercropping of oat (Avena sativa L.) with white lupin (Lupinus albus L.) affects the mobile fractions of trace metals (Fe, Mn, Pb, Cd, Th, U, Sc, La, Nd, Ge) in soil solution. Oat and white lupin were cultivated in monocultures and mixed cultures with differing oat/white lupin ratios (11% and 33% lupin, respectively). Temporal variation of soil solution chemistry was compared with the mobilization of elements in the rhizosphere of white lupin and concentrations in plant tissues. Relative to the monocrops, intercropping of oat with 11% white lupin significantly increased the concentrations of Fe, Pb, Th, La and Nd in soil solution as well as the concentrations of Fe, Pb, Th, Sc, La and Nd in tissues of oat. Enhanced mobility of the mentioned elements corresponded to a depletion of elements in the rhizosphere soil of white lupin. In mixed cultures with 33% lupin, concentrations in soil solution only slightly increased. We conclude that intercropping with 11% white lupin might be a promising tool for phytoremediation and phytomining research enhancing mobility of essential trace metals as well as elements with relevance for phytoremediation (Pb, Th) and phytomining (La, Nd, Sc) in soil.  相似文献   
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Summary Two types of endocrine cells in the basal layer of the keratinized stratified squamous epithelium in the guinea-pig esophagus were studied with immunohistochemistry by means of a streptavidin-biotin-bridge technique and by the immunofluorescence double-labelling technique. Cell-type I exhibited immunoreactivity to chromogranin A and to nucleosidetriphosphate-adenosinediphosphate(ADP)-phosphotransferase. Ultrastructurally, this cell type was characterized by small cytoplasmic dense-core vesicles in which immunoreactive product was localized. Cell-type II contained large membrane-limited granules, which were moderately electron dense. These granules displayed somatostatin immunoreactivity. Both cell types were located in close vicinity to non-myelinated nerve fibers and small blood vessels. The results provide evidence that, independent from the type of lining epithelium, the gastro-enteropancreatic system in guinea-pig extends to the lower portion of the esophagus.Supported by the German Research Foundation, grant He 919/6-2  相似文献   
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A new approach to avoid typical complications from bone marrow transplantation into MHC different mice was studied. Rat monoclonal anti-Thy-1 antibodies of the IgG 2b isotype were identified, which inhibit T lymphocytes in vivo so that transplanted donor T cells as well as residual T cells of the conditioned marrow recipient were suppressed. A single injection of these antibodies after irradiation and before marrow transplantation did not only prevent graft-versus-host mortality but suppressed also host-versus-graft reactivity so that the radiation dose necessary for engraftment of donor cells differing in H-2, IA (both haplotypes) major histocompatibility antigens could be reduced to 6.0 Gy. In addition an anti-T leukemic cell effect from the injected monoclonal T cell antibodies was observed.  相似文献   
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The eruption time of deciduous teeth of the Bengalee children was noted and compared with the published material from other countries. It has been seen that the onset of eruption in the Bengalee children is appreciably late compared with the others (Japanese, Korean, American and Whites).  相似文献   
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Regulatory peptides in paraganglia   总被引:2,自引:0,他引:2  
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