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991.
992.
993.
The antimicrobial activity of two clavine-type ergot alkaloids (agroclavine, festuclavine), and 16 derivatives against four human pathogenic bacteria and Candida albicans was determined. It is shown that all ergolines tested with one exception exhibit antibacterial properties against one to four bacteria species. The most active compounds are 6-allyl-6-norfestuclavine (minimal inhibitory concentration (MIC) 30 micrograms/ml against Staphylococcus aureus), 1-propyl-6-norfestuclavine (MIC 60 micrograms/ml against Escherichia coli), 6-cyano-6-norfestuclavine (MIC 250 micrograms/ml against Pseudomonas aeruginosa), and 1-methyl-agroclavine (MIC 200 micrograms/ml against Proteus vulgaris). 1-Allyl-6-norfestuclavine and 1-propyl-6-norfestuclavine showed a broad action spectrum: the growth of all four bacteria species and of Candida albicans was inhibited. The most effective antifungal compounds are 1-propyl-6-norfestuclavine and 6-cyano-6-norfestuclavine (MIC 250 micrograms/ml). Three alkaloids of different structure (codeine, emetine, quinine) are inactive up to 500 micrograms/ml against the bacteria species and C. albicans. The acute toxicity (mouse) is remarkably diminished by the modifications of the natural clavines. 相似文献
994.
Loss of muscarinic M1 receptors with aging in the cerebral cortex of Fisher 344 rats 总被引:1,自引:0,他引:1
R D Schwarz A A Bernabei C J Spencer T A Pugsley 《Pharmacology, biochemistry, and behavior》1990,35(3):589-593
Age-related changes in central cholinergic muscarinic receptors were measured in young (3-6 month), middle-aged (15-17 month), and aged (22-26 month) male Fisher 344 rats by receptor binding techniques. Using [3H]-quinuclidinyl benzilate as the ligand, a significant decrease (14-19%) in the number of muscarinic cortical receptors was measured in aged rats compared to both young and middle-aged rats. With the selective M1 antagonist, [3H]-pirenzepine, a 17% decrease in receptor density was observed in the cortex of aged animals compared to young rats. For both ligands no differences were observed in the striatum or hippocampus between any age group and there was no change in affinity (Kd) in any of the three brain regions for the three age groups. Additionally, there was no difference in choline acetyltransferase activity measured in cortex, hippocampus, or striatum of young and aged rats. Thus, there is a loss of M1 muscarinic receptors in the cerebral cortex of aged male Fisher 344 rats. 相似文献
995.
996.
The case of a patient who had renal cell carcinoma with cytoplasmic eosinophilic globular hyaline bodies antigenically similar to Mallory bodies, highly suggestive of globular type III alcoholic hyalin, is presented. Mallory bodies are not found exclusively in the liver, having also been demonstrated in the lung. The renal tumor in this case represents an additional extrahepatic site. 相似文献
997.
Electrophoretic patterns of spermatozoal nucleoproteins (NP) in fertile men and infertility patients and comparison with NP of somatic cells 总被引:6,自引:0,他引:6
During spermatogenesis in mammals the evolutionary early histones are replaced step by step by more species specific nucleoproteins (protamines). The protamines protect the genetic information of the male against mutagenic or other damaging influences and possibly play a role in male fertility. A method was presented to study the nucleoproteins (NP) of single human ejaculates. This procedure was checked concerning its usability and validity by bull spermatozoa. The NP of cryopreserved human spermatozoa of fertile men and of infertility patients were investigated and compared with the electrophoretic patterns of NP of somatic hepatocytes of rat and mouse. A total of 48 semen samples were studied. Ten of these samples were obtained from semen donors of proven fertility and 38 samples were collected from male partners of infertile couples. Photodensitometrically it could be distinguished between percentages of non-protamines (PNP) and percentages of protamines (PP). The PP varied intra-individually with a mean standard deviation of 34%, analogously to the alterations of classical semen parameters. The PP of fertile men did not significantly differ from the infertility patients with normal spermiogram parameters but showed a significantly higher value compared with the semen samples with pathological spermiograms. On average the PP of all infertile patients were significantly lower than the PP of fertile semen donors. 相似文献
998.
K O Schwarz 《Medical hypotheses》1988,27(3):189-191
The transmissible spongiform encephalopathies are probably caused by infectious proteinaceous agents called prions. It is suggested that these encephalopathies may be amenable to treatment by substances which inhibit protein synthesis. 相似文献
999.
A panel of 17 monoclonal antibodies (MAbs), which are reactive with purified carcinoembryonic antigen (CEA), was tested. The MAbs were categorized into 6 groups according to their reactivity with CEA 180, CEA 160, non-specific cross-reacting antigen (NCA) 97 and NCA 50. After chemical modification of CEA (reduction, carboxymethylation, deglycosylation, enzymatic cleavage) and binding studies, the MAbs were further divided into 8 subgroups, representing 8 different antigenic sites on CEA. All MAbs bind to deglycosylated CEA. Most of the MAbs are directed against conformational determinants, since only three of them recognize reduced and alkylated CEA. The same three MAbs are able to detect 29 kDa glycosylated fragments obtained by enzymatic cleavage of CEA. These three protease V8- and trypsin-resistant fragments, probably obtained by interdomain cleavage, show a close relationship in peptide patterns, supporting the repeating structural domain-model of CEA as deduced from the cDNA sequence of CEA. 相似文献
1000.
H. G. Schwarz 《Sozial- und Pr?ventivmedizin》1963,8(1):191-194
Zusammenfassung Jugendliche, die w?hrend der Schicht durch die Arbeit am wenigsten beansprucht wurden—die 14j?hrigen von über Tage und die
16j?hrigen aus der Grube —, weisen nach dem Aufenthalt in der Waschkaue auch den geringsten Pulsfrequenzanstieg auf. Dagegen
zeigen die 17j?hrigen durch das Verhalten ihrer K?rpertemperatur, ihres Pulses und ihres Blutdruckes, da? sie durch den
Résumé Des travailleurs de 14 ans occupés en dehors des mines et des travailleurs de 16 ans travaillant sous terre présentent une augmentation faible de la fréquence cardiaque, mesurée immédiatement après les bains consécutifs au travail. Par contre, les ouvriers de 17 ans révèlent par leur réaction de la température corporelle, de la fréquence cardiaque et de la pression artérielle相似文献