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排序方式: 共有1306条查询结果,搜索用时 109 毫秒
1.
H.U. Schweikert U.W. Tunn U.-F. Habenicht J. Arnold Th. Senge H. Schulze F.H. Schrder J.H.M. Blom O. Ennemoser W. Horniger G. Bartsch 《The Journal of steroid biochemistry and molecular biology》1993,44(4-6):573-576
Sex steroids are thought to play an essential role in the pathogenesis of human benign prostatic hyperplasia (BPH). Since recent studies in animal models and in men have shown that estrogens might be causally linked to the onset and maintenance of BPH, we examined the effect of 1-methyl-androsta-1,4-diene-3,17-dione (Atamestane), a newly developed aromatase inhibitor, in men with BPH. In an open multicenter study 49 men (mean age 70.1 years, range 55 to 84) with obstructive BPH were treated with atamestane (3 × 200 mg/day) for 3 months. Of the 49 patients 44 completed the treatment period; the other patients discontinued the study for reasons unrelated to treatment. With treatment BPH-related symptoms such as daytime voiding frequency, nycturia, peak flow and residual urine improved considerably; however, these parameters did not reach statistical significance. The mean prostatic volume decreased significantly from 74.2 ± 31.7 to 64.0 ± 31 ml (mean ± SD). Serum estrogen levels decreased markedly during treatment. In addition intraprostatic estrogen concentration decreased with treatment as compared to estrogen levels in hyperplastic prostates from untreated patients. The following conclusions can be drawn from this study: first, estrogens appear to have an important supportive role in established BPH, and second, estrogen deprivation improved BPH-related symptoms and reduced significantly prostatic volume. 相似文献
2.
Herren T.; Bartsch P.; Haeberli A.; Straub P. W. 《Journal of applied physiology》1992,73(6):2499-2504
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Denise Risch Nicholas J. Gales Jason Gedamke Lars Kindermann Douglas P. Nowacek Andrew J. Read Ursula Siebert Ilse C. Van Opzeeland Sofie M. Van Parijs Ari S. Friedlaender 《Biology letters》2014,10(4)
For decades, the bio-duck sound has been recorded in the Southern Ocean, but the animal producing it has remained a mystery. Heard mainly during austral winter in the Southern Ocean, this ubiquitous sound has been recorded in Antarctic waters and contemporaneously off the Australian west coast. Here, we present conclusive evidence that the bio-duck sound is produced by Antarctic minke whales (Balaenoptera bonaerensis). We analysed data from multi-sensor acoustic recording tags that included intense bio-duck sounds as well as singular downsweeps that have previously been attributed to this species. This finding allows the interpretation of a wealth of long-term acoustic recordings for this previously acoustically concealed species, which will improve our understanding of the distribution, abundance and behaviour of Antarctic minke whales. This is critical information for a species that inhabits a difficult to access sea-ice environment that is changing rapidly in some regions and has been the subject of contentious lethal sampling efforts and ongoing international legal action. 相似文献
6.
M Bartsch 《The Journal of biological chemistry》1985,260(1):237-241
Immunological homology between chloroplast ribosomal proteins (r-proteins) from a higher plant (Spinacia) and bacterial r-proteins was examined using antibodies prepared against 35 purified Escherichia coli r-proteins. Cross-reactions were determined on cellulose acetate gels and on nitrocellulose paper, after electrophoretic transfer of r-proteins from one- and two dimensional polyacrylamide gels, using peroxidase and fluorescein-conjugated second antibodies for detection (immunoblotting). The specificity of positive cross-reactions was confirmed by absorption experiments using purified E. coli r-proteins. Antisera against five proteins of the small subunit and six proteins of the large subunit of E. coli ribosome (i.e. anti-S7, -S9, -S11, -S12, and -S19; anti-L1, -L2, -L3, -L6, -L13, and -L17) gave cross-reactions. As an inference from this work, and a recent study on the synthesis of certain chloroplast r-proteins in isolated chloroplasts (Eneas-Filho, J., Hartley, M. R., and Mache, R. (1981) Mol. Gen. Genet. 184, 484-488), we suggest that chloroplast r-proteins S7 and L2 are encoded in the organelle DNA. 相似文献
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Ilse Schwinck 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1953,35(3):167-174
Zusammenfassung Der Weibchenduftstoff von Plodia interpunctella Hb. ist, entgegen den Angaben Barths, auch bei Zimmertemperatur sehr stabil; geringe Mengen (von 2 in 4 min abgegebener Duftstoff) konnten nach über 2 Tagen in einer geschlossenen Schale durch den Schwirrtanz der Männchen noch nachgewiesen werden.Zur Frage der Artspezifität der Sexualduftstoffe zeigten Versuche in geschlossenen Schalen, im freien Flugkäfig und in luftdurchströmten Apparaturen für die beiden nahe verwandten Gattungen Plodia interpunctella Hb. und Ephestia kühniella Z. keine Spezifität des Erregungs und Anlockungsvorganges, zu einer Kopulation zwischen gattungsfremden Tieren kam es aber trotz wilder Kopulationsversuche nicht. 相似文献
9.
The pH dependence of the spectra and of the oxidation-reduction potential of three cytochromes c2, from Rhodopseudomonas capsulata, Rhodopseudomonas sphaeroides and Rhodomicrobium vannielii, were studied. A single alkaline pK was observed for the spectral changes in all three ferricytochromes. In Rps. capsulata cytochrome c2 this spectroscopic pK corresponds to the pK observed in the dependence of oxidation-reduction potential on pH. For the other two cytochromes the oxidation-reduction potential showed a complex dependency on pH which can be fitted to theoretical curves involving three ionizations. The third ionization corresponds to the ionization observed in the spectroscopic studies but the first two occur without changes in the visible spectra.The possible structural bases for these ionizations are discussed. 相似文献
10.
Peter L Hagedoorn Martijn C.P.F Driessen Marieke van den Bosch Ilse Landa Wilfred R Hagen 《FEBS letters》1998,440(3):6683
The redox chemistry of Pyrococcus furiosus rubredoxin and ferredoxin has been studied as a function of temperature in direct voltammetry and in EPR monitored bulk titrations. The Ems of both proteins, measured with direct voltammetry, have a normal (linear) temperature dependence and show no pH dependence. EPR monitoring is not a reliable method to determine the temperature dependence of the Em: upon rapid freezing the proteins take their conformation corresponding to the freezing point of the solution. 相似文献