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31.
Zusammenfassung 1. 2,4-D in einer Dosis, die in vivo Myotonie hervorruft, steigert in vitro am Zwerchfellpräparat die Atmung und die Lactatproduktion, sowohl in einem K- wie auch in einem Nareichen Inkubationsmedium.2. In vivo wurden nach 2,4-D in myotonieerzeugender Dosis G-6-P, F-6-P, FDP, DAP, -GP, Pyruvat und Lactat vermehrt im ruhenden Skeletmuskel (Bauchmuskulatur) gefunden, woraus auf eine gesteigerte Glykolyse geschlossen wurde.3. Kreatinphosphat nahm unter den gleichen Bedingungen wie unter 2. ab. ATP und ADP blieben praktisch unverändert.4. Die unter 1., 2. und 3. erwähnten Befunde werden hypothetisch entweder mit Entkoppelung der oxydativen Phosphorylierung oder einem induzierten bzw. gesteigerten energieverbrauchenden Prozeß in Zusammenhang gebracht. Dabei wäre auch die Kombination dieser beiden energiereduzierenden Prozesse möglich.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Summary 1. A dose of 2,4-D (which brings about myotonia in vivo), increases O2-consumption in vitro and increases the production of lactate in potassium as well as sodium rich incubating media.2. In vivo, after a dose of 2,4-D which brought about myotonia, an increase of G-6-P, F-6-P, FDP, DAP, -GP, pyruvate, and lactate was found in the abdominal skeletal muscles at rest. This finding indicated an increase in glycolysis.3. Under the same conditions as in paragraph 2 creatine-phosphate was decreased. ATP and ADP practically unchanged.4. There is a hypothetical connection between the findings mentioned in paragraphs 1, 2 and 3 either in the view of uncoupling of the oxydative phosphorylation or in the view of a process involving an increase in energy consumption. With that, a combination of both energy reducing processes would also be possible.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
32.
Construction and characterization of Listeria monocytogenes mutants with in-frame deletions in the response regulator genes identified in the genome sequence 下载免费PDF全文
Two-component systems are widely distributed in prokaryotes where they control gene expression in response to diverse stimuli. To study the role of the sixteen putative two-component systems of Listeria monocytogenes systematically, in frame deletions were introduced into 15 out of the 16 response regulator genes and the resulting mutants were characterized. With one exception the deletion of the individual response regulator genes has only minor effects on in vitro and in vivo growth of the bacteria. The mutant carrying a deletion in the ortholog of the Bacillus subtilis response regulator gene degU showed a clearly reduced virulence in mice, indicating that DegU is involved in the regulation of virulence-associated genes. 相似文献
33.
Zusammenfassung Bei 15 Patienten mit myotonischer Dystrophie (10 männliche und 5 weibliche) haben wir die 17-Ketosteroide im Urin untersucht. Sie lagen in der Regel im unteren Normbereich oder waren gering vermindert.Die Fraktionen der 17-Ketosteroide konnten wir bei 6 männlichen und 2 weiblichen Patienten aus dieser Untersuchungsreihe bestimmen. Dabei zeigte sich, daß zwar entsprechend der herabgesetzten Ausscheidung der 17-Ketosteroide anteilig auch die Fraktionen vermindert sind, von ihnen aber keine fehlt. Auch für eine erhebliche Verschiebung innerhalb der 17-Ketosteroide zugunsten oder zuungunsten einer Fraktion findet sich bei unseren 8 Patienten kein Anhalt. 相似文献
34.
Kennedy CM Coutsoudis A Kuhn L Pillay K Mburu A Stein Z Coovadia H 《Journal of acquired immune deficiency syndromes (1999)》2000,24(1):37-44
OBJECTIVE: To determine whether low-cost treatment of HIV using vitamin A would be beneficial, we examined the effect of vitamin A supplementation on morbidity of HIV-1 infected women. METHODS: We conducted a randomized, double blind placebo-controlled trial at King Edward VIII Hospital, in Durban, South Africa. In total, 312 HIV-seropositive pregnant women between 28 and 32 weeks' gestation were recruited into this trial. Patients were randomized to receive placebo or 5,000 IU retinyl palmitate and 30 mg beta-carotene daily. At delivery of their children, patients received placebo or 200,000 IU retinyl palmitate. The main outcome measures were pre- and postnatal report of HIV-related symptoms. RESULTS: Vitamin A did not confer any significant beneficial effect on the report of either HIV or pregnancy-related symptoms during the pre- or postnatal period. CONCLUSION: In this study of HIV-infected pregnant women, vitamin A supplementation given in doses designed to decrease mother-to-infant transmission did not result in significant beneficial effect on reported symptoms pre- or postnatally. Further investigation with larger number of participants, tailoring supplementation for specific clinical conditions, outside the context of pregnancy, is required to help clarify the possible clinical benefits of vitamin A. 相似文献
35.
36.
Cell-free virus in breast milk of HIV-1-seropositive women 总被引:4,自引:0,他引:4
37.
Effect of elevated environmental temperature on the antibody response of mice to Trypanosoma cruzi during the acute phase of infection. 下载免费PDF全文
When held at 36 degrees C, Trypanosoma cruzi-infected C3H mice survive an otherwise lethal infection with significantly decreased parasitemia levels and enhanced immune responsiveness. Treatment of T. cruzi-infected mice with the immunosuppressive agent cyclophosphamide indicated that the positive effects of increased environmental temperature were primarily due to enhancement of immunity. A parasite-specific, enzyme-linked immunosorbent assay and immunoblot analysis were used to examine the effect of elevated environmental temperature on the production of anti-T. cruzi antibodies. Both the reactivity and diversity of anti-T. cruzi antibodies were found to be lower in infected mice held at 36 degrees C than in infected mice held at room temperature. However, reactivity and diversity could be enhanced by vaccination with culture forms of the parasite. 相似文献
38.
Identification and characterization of fast-sedimenting SV40 nucleoprotein complexes. 总被引:19,自引:0,他引:19
Simian virus 40 (SV40) nucleoprotein complexes were extracted from nuclei of infected monkey cells and fractionated on neutral sucrose density gradients. Four forms of SV40 chromatin were distinguished by their labeling kinetics and apparent sedimentation coefficients: Replicating viral DNA in 95 S SV40 chromatin was converted to 75 S chromatin when viral DNA replication was completed. A portion of the 75 S chromatin was rapidly assembled into 200 S nucleoprotein complexes and subsequently into 240 S complexes. The 75 S and the fast-sedimenting complexes were further characterized and compared with mature SV40 virus by equilibrium density centrifugation, plaque assay, and electron microscopy. These experiments suggest that the fast-sedimenting forms may represent virion precursors or a subclass of salt-labile virions, but they contain little or no mature virus. 相似文献
39.
G. A. Franklin M. Turina J. F. Kuhn R. Turpen J. C. Peyton W. G. Cheadle 《Inflammation research》2006,55(4):136-143
Background Leukocyte apoptosis allows safe removal of potentially harmful cells and facilitates resolution of inflammation. We hypothesized
that the number of apoptotic cells changes in a disproportionate fashion in parenchymal organs in response to intra-abdominal
infection.
Materials and methods The percentage of apoptotic cells in the liver, spleen, lung, and peripheral blood was evaluated following cecal ligation
and puncture (CLP) in mice. Tissue myeloperoxidase (MPO) levels were measured as an index of neutrophil extravasation.
Results Liver & spleen MPO continually increased, while lung MPO remained low after CLP. In parallel to the increase in MPO, liver
& spleen apoptosis continually increased throughout the 9-day follow-up period, whereas lung apoptosis remained unchanged.
Conclusions The distribution of apoptotic cells during intraperitoneal infection occurs in an organ specific manner, with significant
increases in the spleen and liver. This distribution likely reflected the clearance of apoptotic cells as the inflammatory
focus became contained.
Supported by the American Association for the Surgery of Trauma, John H. Davis Research Scholarship, and by the Veterans Administration
Merit Review Project 0005.
Received 7 October 2005; returned for revision 22 November 2005; accepted by G. Wallace 23 December 2005 相似文献
40.
Werner Kuhn 《Journal of molecular medicine (Berlin, Germany)》1959,37(19):997-1003
Ohne ZusammenfassungVortrag anläßlich der Überreichung der Urkunde eines Dr. med. h. c. der medizinischen Fakultät der Universität Kiel, gehalten vor der Kieler Medizinischen Gesellschaft und dem Ortsverband Kiel der Gesellschaft Deutscher Chemiker am 5. Mai 1959.Aus dem Physikalisch-Chemischen Institut der Universität Basel, Direktor: Prof. Dr.W. Kuhn. 相似文献