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41.
Herein we describe a case of a hemorrhagic adrenal pseudocyst that had been initially suspected as being a renal adenocarcinoma. The intraoperative anatomopathological study of the specimen permitted performing conservative surgery. The diagnosis and pathogenesis of this uncommon disease entity are discussed. 相似文献
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In the present study, the effects of compounds extracted from Tanacetum microphyllum, four flavonoids and one sesquiterpene lactone, on arachidonic acid metabolism in cellular systems were examined. In the PGE2- and LTC4-release assay, most compounds did not exhibit any significant effect. Only hydroxyachillin, and the flavonoids centaureidin and 5,3'-dihydroxy-4'-methoxy-7-methoxycarbonylflavonol showed a significant effect, although with less potency than the reference drugs, indomethacin and NDGA. However, all compounds inhibited the release of TXB2 from ionophore-stimulated human platelets. The action is more marked with the flavonoids santin and ermanin. 相似文献
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DF Goldsmith 《Canadian Metallurgical Quarterly》1998,13(2):389-415
Contrary to general opinion, workers' compensation data can be helpful in epidemiologic research. Dr. Goldsmith assesses several studies based on data culled from workers' compensation or disability programs and explains how valuable information was derived. 相似文献
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DF Moores 《Canadian Metallurgical Quarterly》1998,143(4):291-292
The paper discusses the problem about the ergonomic assessment of the abilities of the auditory analyzer for processing of speech information, depending on the zoning of the masking effect of noise and the degree of speech communication. A significant increase of the loss of speech information with rise of the intensities of the masking effect of noise (from 21.33% at L eq. 40 dB up to 96% at L eq. 90 and less than 90 dB/A/) is found. The speech communication is graded into 4 bands, depending on the qualitative-quantitative criteria of the processed speech communication. The regularity of the standard for masking noise (L eq. 65 dB/A), which guarantees good comprehensibility is proved from the aspect of ensuring the necessary conditions for speech information perception. Equivalent levels of masking noise near or equal to L eq. 85 dB/A/ ensure satisfactory comprehensibility at the control boards. The abnormal intensities of the masking noise effect are of particular importance as they belong to the inadmissible (bad) zone of auditory perception of speech information. 相似文献
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K Roeleveld DF Stegeman HM Vingerhoets A Van Oosterom 《Canadian Metallurgical Quarterly》1997,161(4):465-472
Dextransucrase (DSRS) from Leuconostoc mesenteroides NRRL B-512F is a glucosyltransferase that catalyzes the synthesis of soluble dextran from sucrose or oligosaccharides when acceptor molecules, like maltose, are present. The L. mesenteroides NRRL B-512F dextransucrase-encoding gene (dsrS) was amplified by the polymerase chain reaction and cloned in an overexpression plasmid. The characteristics of DSRS were found to be similar to the characteristics of the extracellular dextransucrase produced by L. mesenteroides NRRL B-512F. The enzyme also exhibited a high homology with other glucosyltransferases. In order to identify critical amino acid residues, the DSRS sequence was aligned with glucosyltransferase sequences and four amino acid residues were selected for site-directed mutagenesis experiments: aspartic acid 511, aspartic acid 513, aspartic acid 551 and histidine 661. Asp-511, Asp-513 and Asp-551 were independently replaced with asparagine and His-661 with arginine. Mutation at Asp-511 and Asp-551 completely suppressed dextran and oligosaccharide synthesis activities, showing that at least two carboxyl groups (Asp-511 and Asp-551) are essential for the catalysis process. However, glucan-binding properties were retained, showing that DSRS has a two-domain structure like other glucosyltransferases. Mutations at Asp-513 and His-661 resulted in greatly reduced dextransucrase activity. According to amino acid sequence alignments of glucosyltransferases, alpha-amylases or cyclodextrin glucanotransferases, His-661 may have a hydrogen-bonding function. 相似文献
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DF Paulson 《Canadian Metallurgical Quarterly》1977,28(11):1226-1229
All males treated with long-term, low-dose clomiphene citrate retrospectively were categorized as having pregerminal, primary germinal, or postgerminal hypofertility and their response to treatment was observed. Among couples in which no female factor could be identified and the husband was categorized as demonstrating pregerminal hypofertility, a pregnancy rate of 42% was established after treatment. 相似文献