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41.
Haberberger Rainer; Schemann Michael; Sann Holger; Kummer Wolfgang 《Journal of applied physiology》1997,82(2):426-434
Haberberger, Rainer, Michael Schemann, Holger Sann, andWolfgang Kummer. Innervation pattern of guinea pig pulmonary vasculature depends on vascular diameter. J. Appl.Physiol. 82(2): 426-434, 1997.The pulmonaryvasculature is supplied by various neurochemically distinct types ofnerve fibers, including sensory substance P-containing and autonomicnoradrenergic, nitrergic, and cholinergic axons.Pharmacological experiments have suggested that various segments of thepulmonary vascular tree respond differently to the respectiveneuromediators. We, therefore, aimed to determine histochemically andimmunohistochemically for each of these neurochemically distinctperivascular axons their quantitative distribution along the vasculartree from the extrapulmonary trunks to the smallest intraparenchymalramifications in control guinea pigs(n = 5). Generally, arterialinnervation was more developed than that of veins. Along the arterialtree, noradrenergic and substance P-containing axons were ubiquitousfrom the pulmonary trunk to smallest intraparenchymal vessels, whereasnitrergic axons were practically restricted to large (>700-µm)extrapulmonary arteries. Cholinergic axons were regularly present atarteries down to 100 µm in diameter and innervated two-thirds ofsmall arteries (50-100 µm). The results demonstrate thatthe noradrenergic vasoconstrictor innervation extends throughout thepulmonary vascular system whereas the innervation pattern with varioustypes of vasodilator fibers changes with vascular diameter, parallel toknown pharmacological differences in cholinergic and nitrergicvasodilator effects. 相似文献
42.
David Liti Jonathan Munguti Norbert Kreuzinger Helmut Kummer 《African Journal of Ecology》2005,43(3):170-176
A 2 × 2 factorial experiment was conducted between April and August 2001 to evaluate the effects of NaCl on Oreochromis niloticus growth and water quality in twelve 0.015 ha limed ponds. The design involved fertilizer and salt as factors with two treatments for each factor. Each salt‐fertilizer combination was replicated three times and fish were not offered external food during the 98 days culture. Growth of O. niloticus was significantly enhanced by salt at higher fertilizer level but not at the lower fertilization level. Although salt had no direct effect on fish growth, a significant salt‐fertilizer interaction was demonstrated. Water quality variables, with a few exceptions, were similar among the salted treatments. Total ammonia increased significantly with fertilization level, but the values were similar in salted and unsalted treatments at the same fertilizer level. Total nitrogen was higher in the salted than unsalted treatments while the organic matter content was lower in the salted treatments. The reasons for the better growth of O. niloticus, are discussed with respect to water quality variables. The present results suggest that fertilization rates of 20 kg N ha?1 may have negative effects on fish growth. However, presence of sodium chloride seems to reduce these negative effects. 相似文献
43.
Oliver Wiche Balazs Székely Nicolai-Alexeji Kummer Christin Moschner Hermann Heilmeier 《International journal of phytoremediation》2016,18(9):900-907
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
44.
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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46.
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
47.
Otto T. Solbrig John Skok David French John W. Thieret Kling L. Anderson M. T. Hilborn John Popenoe Floyd Swink George L. Mcnew Ray Schulenberg William L. Stern William G. Walter T. W. Fisher C. Earle Smith Wynne Thoene Anna P. Kummer Hugh Cutler Alexander H. Smith Henry T. Skinner Joseph H. Caro Harold F. Madsen L. W. R. Jackson Lawrence Kaplan Duane Isely Alphons Th. Czaja Willard A. Taber 《Economic botany》1961,15(2):180-204
48.
Eva Kummer Katharina Noel Schubert Tanja Schoenhut Alain Scaiola Nenad Ban 《Molecular cell》2021,81(12):2566-2582.e6
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50.
H Kummer 《American journal of physical anthropology》1967,27(3):357-366
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