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81.
Gerhard Horstmann Renate Lüllmann-Rauch 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,48(1):33-45
The purpose of this study was to examine whether the aortic and mitral valves of rats are involved in the mucopolysaccharidosis-like disorder induced by tilorone. Rats were treated with large doses of the drug for periods of 1-21 weeks. After chronic drug treatment the leaflets of both heart valves were thickened and opaque. In all treated animals the spongiosa layer of the stroma was crowded with vacuolated cells; the fibrosa layer was altered only after prolonged treatment. Ultrastructurally, the vacuolated cells of the spongiosa could be identified as histiocytes and fibroblasts, the former being the most susceptible cell type. The fibroblasts of the fibrosa represented the least sensitive cell type. The histochemical results showed that the clear cytoplasmic vacuoles in the spongiosa cells were due to lysosomal storage of polyanionic material with staining characteristics similar to cartilage matrix. After discontinuation of drug treatment the alterations persisted for several weeks. The present study shows that heart valves are involved in the mucopolysaccharidosis-like disorder induced by tilorone. The molecular pathomechanism of the disorder and the exact identification of the storage material must await further analysis. 相似文献
82.
83.
Andreas H. Kottmann Gerhard H. A. Seemann H. Detlef Guessow Marleen H. Roos 《Immunogenetics》1986,23(6):396-400
An HLA-B44 cDNA clone was identified in a cDNA library constructed from an HLA-B44 homozygous cell line. The DNA sequence was determined and was found to contain the complete coding sequence but for (probably) the three N-terminal codons. Comparisons of the derived amino acid sequence with other HLA-A and -B locus amino acid sequences revealed four HLA-B44-specific substitutions including a new polymorphic site. Regions of strong sequence conservation for HLA-B-locus products were found at the nucleotide and amino acid levels. 相似文献
84.
Summary Two new microcarriers were tested and showed good properties in cell attachment, cell growth and production of Human--Interferon. Cell densities up to 5·106 cells/ml on microcarriers were reached in 1 l bioreactors. 相似文献
85.
H. Schulz 《Zeitschrift fur angewandte Ichthyologie》1986,2(3):117-124
Turbot (Scophthalmus maximus) of approximate 110 g mean wet weight were fed three different diets supplemented with DL-alpha-tocopherol (1.4 g and 2.45 g · kg-1 basal diet) and with non-alphatocopherols (0.29 g beta-, 1.29 g gamma-and 0.68 g delta-tocopherol kg-1 basal diet). High dosages of alpha-tocopherol caused a linear increase of liver tocopherol (ninefold to controls). Spleen and blood serum accumulated also tocopherol. The level in muscle tissue was only poorly influenced by high vitamin E dosage. Non-alpha-tocopherols which normally do nct occur in blood and tissue have been resorbed from experiment diets and deposed in tissues in the same manner as alpha-tocopherol. The distribution of various tocopherols in the diets was reflected in muscle, spleen and serum of the fishes in the experiment. In the liver the distribution pattern of tocopherols was different to that of the diet. Conversion of alpha-tocopherol to non-alpha-tocopherpls in-vivo has not been found. 相似文献
86.
Summary An overflow filtration unit for cell recycle with Clostridium acetobutylicum was developed. A cellulose-triacetate ultrafiltration membrane with a cut-off volume of 20 000 MW was found to work best. C. acetobutylicum was grown in continuous culture under phosphate limitation (0.74 mM) at a pH value of 4.4 with cell recycle, the cell dry weight in the culture vessel reached 13.1 g/l at a dilution rate of D=0.10 h-1 and 37°C. 377 mM of glucose were fermented to 190 mM butanol, 116.2 mM acetone and 25.8 mM ethanol. Total acids were 47.6 mM. The butanol productivity was 1.41 g/l/h. At a dilution rate of 0.40 h-1 the butanol productivity was increased to 4.1 g/l/h but glucose consumption was decreased to 285 mM and butanol, acetone and ethanol production to 138.2, 97.5, 16.5 mM, respectively. 相似文献
87.
88.
Ten strains representing a novel genus of marine thermophilic archaebacteria growing at between 70 and 103°C with an optimal growth temperature of 100°C and a doubling time of only 37 min were isolated from geothermally heated marine sediments at the beach of Porto di Levante, Vulcano, Italy. The organisms are spherical-shaped, 0.8 to 2.5 m in width and exhibit monopolar polytrichous flagellation. They are strictly anaerobic heterotrophs, growing on starch, maltose, peptone and complex organic substrates. Only CO2 and H2 could be detected as metabolic products, the latter being inhibitory to growth at high concentrations. Hydrogen inhibition can be prevented by the addition of So, whereupon H2S is formed in addition, most likely as the result of a detoxification reaction. The GC-content of the DNA of isolate Vc 1 is 38 mol%. The new genus is named Pyrococcus, the fireball. Type species and strain is Pyrococcus furiosus Vc 1 (DSM 3638). 相似文献
89.
Gerhard Sandmann 《Archives of microbiology》1986,145(1):76-79
Fifteen species from different genera of blue-green algae have been examined for their formation of plastocyanin (PC) and cytochrome c-553 (cyt c-553) in high or low Cu media. In addition to species which contain only cyt c-553 and those which completely exchange their cyt c-553 by PC, a new regulatory type was detected in which this exchange was incomplete. By comparing different species, it could be shown that either this incomplete exchange of cyt c-553 by PC as well as lack of PC in some other blue-green algae is not caused by restricted Cu uptake but is due to different biosynthetic and regulatory properties. Occurrence of PC and cyt c-553 cannot be used as a taxonomic criterium to classify blue-green algae. However, formation of either one or both of these redox components fits well into a line of evolution of the photosynthetic apparatus from the blue-green algae via green algae to higher plants.Abbreviations PC
plastocyanin; cyt c-553, cytochrome c-553 相似文献
90.
Distribution and abundance of the planktic foraminifer Neogloboquadrina pachyderma in sea ice of the Weddell Sea (Antarctica) 总被引:4,自引:4,他引:0
Summary Sea ice cores were obtained from eleven fast ice stations and one floe in the Weddell Sea, Antarctica in January–February 1985. All cores from the north eastern part of the Weddell Sea contained numerous living and dead planktic foraminifers of the species Neogloboquadrina pachyderma (Ehrenberg), while cores drilled in southern parts were barren of foraminifers with one exception. Foraminiferal abundances were variable, with numbers up to 320 individuals per liter melted sea ice. Distribution of foraminifers appears to be patchy, parallel cores taken less than 30 cm apart contained numbers which varied considerably. On the other hand, three cores taken on a transect each more than 3 km apart showed striking similarities. In general, small dead tests were found in the upper parts of the sea ice cores while large living individuals mainly occurred in lower sections. Abundant diatoms probably serve as a food source for the foraminifers. Correlation of foraminiferal abundance with salinity, chlorophyll and nutrient profiles are inconsistent. The possible mechanism of incorporation of N. pachyderma into the ice is discussed. 相似文献